JP2020048911A - Ophthalmic imaging apparatus, control method thereof, program, and recording medium - Google Patents

Abstract

Kind Code: A1 To provide a technique capable of acquiring a high-quality image even when optical scanning is applied to a wide range of the posterior segment of the eye at high speed. According to one embodiment, an ophthalmologic imaging apparatus includes a data acquisition unit, a storage unit, an aberration correction unit, and a control unit. The data acquisition unit acquires data by scanning the posterior segment of the subject's eye with light. The storage unit pre-stores a map representing the distribution of the amount of aberration correction in a specific area that is at least part of the area scanned by the data acquisition unit. The aberration correction section corrects at least aberration caused by the subject's eye. The control unit controls the data acquisition unit for scanning the posterior segment region corresponding to the specific area of the map, and controls the aberration correction unit based on the map in a coordinated manner. [Selection drawing] Fig. 4

Description

  The present invention relates to an ophthalmologic photographing apparatus, a control method thereof, a program, and a recording medium.

  In ophthalmological practice, the importance of image diagnosis and image analysis is increasing. In particular, the application of optical coherence tomography (OCT) to ophthalmology has accelerated the trend. OCT enables three-dimensional imaging and three-dimensional structural analysis and functional analysis of an eye to be inspected, and is exerting its power, for example, for acquiring distributions of various measurement values.

  In recent years, the OCT scan range has been expanded, that is, the OCT has been widened. For example, in order to scan a wide range from the center to the periphery of the fundus, a device has been developed that enlarges the deflection angle of an optical scanner (such as a galvanometer mirror) and optimizes the structure, control, and imaging accordingly. (For example, see Patent Documents 1 and 2).

  When an OCT scan (generally a raster scan) is applied to a wide range of the fundus, image quality is deteriorated particularly at a position far away from the center of the fundus (referred to as a peripheral part) due to the aberration of the eyeball optical system. This is because the aberration of the eyeball is larger in the peripheral part than in the central part of the fundus (for example, see Non-Patent Document 1).

  Focus control may be performed to eliminate such image quality degradation. However, since the speed of the focus control is considerably lower than the speed of the OCT scan (for example, the repetition rate of the A-scan), it is realistic to perform the focus control while applying the raster scan at high speed over a wide range of the fundus. Absent.

  On the other hand, a scanning ophthalmic imaging apparatus (OCT, scanning laser ophthalmoscope (SLO)) having an aberration correction function is known. For example, the devices disclosed in Patent Literatures 3 and 4 are configured to scan the fundus while measuring the aberration of the eye to be examined.

  When such an apparatus performs wide-angle scan at high speed, the processing load may be extremely large because aberration measurement, aberration amount calculation, and aberration correction control are performed in parallel with scan control. In addition, there is a problem that hardware and software may be complicated and cost may be increased, and calculation and control may be complicated. Furthermore, it is hardly practical to perform the aberration measurement, the aberration amount calculation, and the aberration correction control at the same speed as the high-speed scan (and to perform them over a wide range of the posterior segment while synchronizing with each other). .

JP-A-2017-086311 JP 2017-047131 A JP 2011-104126 A JP 2015-221097 A

JAMES POLANS, 4 others, `` Wide-field optical model of the human eye with asymmetrically tilted and decentered lens that reproduces measured ocular aberrations '', Optica, February 2015, Vol.2, No.2, p.124-134

  An object of the present invention is to provide a technique capable of acquiring a high-quality image even when optical scanning is applied at high speed over a wide range of the posterior segment.

  An ophthalmologic imaging apparatus according to a first aspect of the exemplary embodiment includes a data collection unit that scans the posterior segment of the subject's eye with light to collect data, and at least a part of a scan area of the data collection unit. A storage unit that stores in advance a map representing a distribution of the amount of aberration correction in a specific area, an aberration correction unit that corrects at least aberration caused by the eye to be inspected, and scans a region of the posterior segment corresponding to the specific area And a control unit that cooperates with the control of the data collection unit and the control of the aberration correction unit based on the map.

  A second aspect of the exemplary embodiment is the ophthalmologic imaging apparatus of the first aspect, wherein the map stores aberration correction amounts corresponding to a plurality of positions in the specific area. Controlling the data collection unit for scanning one of the plurality of positions, and controlling the aberration correction based on the amount of aberration correction corresponding to the one position recorded in the map. The control of the section is executed in parallel.

  A third aspect of the exemplary embodiment is the ophthalmologic imaging apparatus of the first aspect, wherein the data collection unit includes an optical scanner that deflects light for scanning the posterior segment, and the map The aberration correction amount corresponding to each of the plurality of control information for the optical scanner is recorded, the control unit controls the optical scanner based on one of the plurality of control information control information And controlling the aberration corrector based on the aberration correction amount corresponding to the one control information recorded in the map in parallel.

  A fourth aspect of the exemplary embodiment is the ophthalmologic imaging apparatus according to any one of the first to third aspects, wherein the specific area includes at least a peripheral area of the scan area.

  A fifth aspect of the exemplary embodiment is the ophthalmologic imaging apparatus of the fourth aspect, wherein the control unit is configured to control the first partial pattern and a continuous first partial pattern for a central area of the scan area different from the peripheral area. The control of the data collection unit according to a scan pattern including a continuous second partial pattern with respect to a peripheral area is performed in cooperation with the control of the aberration correction unit based on the map.

  A sixth aspect of the exemplary embodiment is the ophthalmologic imaging apparatus of the fifth aspect, wherein the scan pattern includes a curved scan pattern defined by a polar coordinate system having an origin at the center of the scan area. .

  A seventh aspect of the exemplary embodiment is the ophthalmologic imaging apparatus of the sixth aspect, wherein the curved scan pattern is a spiral scan pattern from a center of the scan area to an outer edge, and the scan area Is a spiral scan pattern that goes from the outer edge to the center.

  An eighth aspect of the exemplary embodiment is the ophthalmologic imaging apparatus of the sixth or seventh aspect, further comprising an image construction unit configured to construct an image from the data collected by the data collection unit, The construction unit forms an image defined in the polar coordinate system from data collected by a scan applied to the posterior segment according to the curved scan pattern, and generates the image defined in the polar coordinate system. The image is converted into an image defined in a three-dimensional orthogonal coordinate system.

  A ninth aspect of the exemplary embodiment is the ophthalmologic imaging apparatus according to any one of the first to eighth aspects, wherein an imaging unit for repeatedly imaging the subject's eye, and a time series acquired by the imaging unit The data collection unit further includes a light scanner that deflects light for scanning the posterior segment, wherein the control unit includes: The optical scanner is controlled based on an output from the movement detection unit while controlling the data collection unit and the aberration correction unit in cooperation.

  A tenth aspect of the exemplary embodiment is the ophthalmologic imaging apparatus according to any one of the first to ninth aspects, wherein the storage unit stores two or more maps corresponding to two or more diopter values in advance. The control unit stores the map corresponding to the diopter value of the subject's eye from the two or more maps, and controls the aberration control unit based on the selected map.

  An eleventh aspect of the exemplary embodiment is the ophthalmologic imaging apparatus according to any one of the first to ninth aspects, wherein the data acquisition unit performs an optical coherence tomography (OCT) scan on the posterior segment. An OCT data collection unit for applying and collecting OCT data, an OCT image construction unit for constructing an OCT image from the OCT data collected by the OCT data collection unit, and the OCT constructed by the OCT image construction unit A map creation unit that creates a map stored in the storage unit based on the image.

  A twelfth aspect of the exemplary embodiment includes a data collection unit that scans the posterior segment of the subject's eye with light to collect data, and an aberration correction unit that corrects at least aberration caused by the subject's eye. A method for controlling an ophthalmic imaging apparatus, comprising: preparing a map representing a distribution of an amount of aberration correction in a specific area that is at least a part of a scan area by the data collection unit; A control step of cooperatively executing control of the data collection unit for scanning a region of the unit and control of the aberration correction unit based on the map.

  A thirteenth aspect of the exemplary embodiment is a program for causing a computer to execute the control method of the ophthalmologic imaging apparatus of the twelfth aspect.

  A fourteenth aspect of the exemplary embodiment is a non-transitory computer-readable recording medium recording the program of the thirteenth aspect.

  According to the exemplary embodiment, it is possible to acquire a high-quality image even when the optical scan is applied at a high speed over a wide range of the posterior segment.

1 is a schematic diagram illustrating an example of a configuration of an ophthalmologic imaging apparatus according to an exemplary embodiment. 1 is a schematic diagram illustrating an example of a configuration of an ophthalmologic imaging apparatus according to an exemplary embodiment. 1 is a schematic diagram illustrating an example of a configuration of an ophthalmologic imaging apparatus according to an exemplary embodiment. 1 is a schematic diagram illustrating an example of a configuration of an ophthalmologic imaging apparatus according to an exemplary embodiment. It is a schematic diagram for explaining an example of processing which an ophthalmologic imaging device concerning an exemplary embodiment performs. It is a schematic diagram for explaining an example of processing which an ophthalmologic imaging device concerning an exemplary embodiment performs. It is a schematic diagram for explaining an example of processing which an ophthalmologic imaging device concerning an exemplary embodiment performs. It is a schematic diagram for explaining an example of processing which an ophthalmologic imaging device concerning an exemplary embodiment performs. It is a schematic diagram for explaining an example of processing which an ophthalmologic imaging device concerning an exemplary embodiment performs. It is a schematic diagram for explaining an example of processing which an ophthalmologic imaging device concerning an exemplary embodiment performs. It is a schematic diagram for explaining an example of processing which an ophthalmologic imaging device concerning an exemplary embodiment performs. It is a schematic diagram for explaining an example of processing which an ophthalmologic imaging device concerning an exemplary embodiment performs. It is a schematic diagram for explaining an example of processing which an ophthalmologic imaging device concerning an exemplary embodiment performs. It is a schematic diagram for explaining an example of processing which an ophthalmologic imaging device concerning an exemplary embodiment performs. It is a schematic diagram for explaining an example of processing which an ophthalmologic imaging device concerning an exemplary embodiment performs. It is a schematic diagram for explaining an example of processing which an ophthalmologic imaging device concerning an exemplary embodiment performs. It is a schematic diagram for explaining an example of processing which an ophthalmologic imaging device concerning an exemplary embodiment performs. 9 is a flowchart illustrating an example of an operation of the ophthalmologic photographing apparatus according to the exemplary embodiment. It is a schematic diagram for explaining an example of operation of an ophthalmologic photographing device concerning an exemplary embodiment. It is a schematic diagram for explaining an example of operation of an ophthalmologic photographing device concerning an exemplary embodiment.

  An ophthalmologic imaging apparatus according to an exemplary embodiment, a control method thereof, a program, and a recording medium will be described in detail with reference to the drawings. The disclosure content of the documents cited in the present specification and any other known techniques can be incorporated into the embodiments. Further, unless otherwise specified, “image data” and “image” based on the image data are not distinguished. Similarly, unless otherwise specified, the “part” of the eye to be inspected is not distinguished from the “image” thereof.

  The ophthalmologic imaging apparatus according to the exemplary embodiment can measure the fundus of a living eye using Fourier domain OCT (for example, swept source OCT). The type of OCT applicable to the embodiment is not limited to the swept source OCT, and may be, for example, a spectral domain OCT or a time domain OCT. Further, the application target of the OCT is not limited to the fundus, and may be any part of the eye such as the anterior segment or the vitreous body.

  Exemplary embodiments may be capable of processing images acquired by modalities other than OCT. For example, exemplary embodiments may be capable of processing images acquired by any of a fundus camera, SLO, slit lamp microscope, and ophthalmic surgical microscope. An ophthalmologic imaging apparatus according to an exemplary embodiment may include any of a fundus camera, an SLO, a slit lamp microscope, and a microscope for ophthalmic surgery.

  The image of the subject's eye that can be processed according to the exemplary embodiment may include an image obtained by analyzing an image obtained by any modality. Examples of such analysis images are obtained by analyzing a pseudo-colored image (eg, a segmented pseudo-color image), an image consisting only of a part of the original image (eg, a segment image), and an OCT image. There are an image representing a tissue thickness distribution (layer thickness map, layer thickness graph, etc.), an image representing a tissue shape (curvature map, etc.), and an image representing a lesion distribution (lesion map, etc.).

<Constitution>
The ophthalmologic imaging apparatus 1 according to the exemplary embodiment illustrated in FIG. 1 includes a fundus camera unit 2, an OCT unit 100, and an arithmetic and control unit 200. The retinal camera unit 2 is provided with an optical system and a mechanism for acquiring a front image of the subject's eye. The OCT unit 100 is provided with a part of an optical system and a mechanism for performing the OCT. Another part of the optical system and the mechanism for performing the OCT is provided in the fundus camera unit 2. The arithmetic and control unit 200 includes one or more processors that execute various calculations and controls. In addition to these, arbitrary elements such as a member for supporting the face of the subject (chin rest, forehead support, etc.) and a lens unit for switching an OCT target site (for example, an anterior segment OCT attachment) And a unit may be provided in the ophthalmologic photographing apparatus 1.

  In this specification, a “processor” is, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), a programmable logic device (for example, an SPLD (Simple Graphical Programmable Programmable Programmable Logic), or a programmable logic device (for example, an SPLD (Simple Programmable Programmable Programmable Logic Programmable Programmable Logic)). It means a circuit such as a programmable logic device (FPGA) or a field programmable gate array (FPGA). The processor realizes the functions according to the embodiment by, for example, reading and executing a program stored in a storage circuit or a storage device.

<Fundus camera unit 2>
The retinal camera unit 2 is provided with an optical system for photographing the fundus oculi Ef of the eye E. The acquired image of the fundus oculi Ef (referred to as a fundus image, a fundus photograph, or the like) is a front image such as an observation image or a photographed image. The observation image is obtained, for example, by moving image shooting using near-infrared light, and is used for alignment, focusing, tracking, and the like. The captured image is, for example, a still image using flash light in a visible region or an infrared region.

  The retinal camera unit 2 includes an illumination optical system 10 and a photographing optical system 30. The illumination optical system 10 irradiates the eye E with illumination light. The imaging optical system 30 detects the return light of the illumination light from the eye E to be inspected. The measurement light from the OCT unit 100 is guided to the eye E through an optical path in the fundus camera unit 2, and the return light is guided to the OCT unit 100 through the same optical path.

  Light (observation illumination light) output from the observation light source 11 of the illumination optical system 10 is reflected by the concave mirror 12, passes through the condenser lens 13, passes through the visible cut filter 14, and becomes near-infrared light. Further, the observation illumination light once converges near the imaging light source 15, is reflected by the mirror 16, and passes through the relay lens system 17, the relay lens 18, the diaphragm 19, and the relay lens system 20. Then, the observation illumination light is reflected at the periphery of the perforated mirror 21 (the area around the perforated portion), passes through the dichroic mirror 46, is refracted by the objective lens 22, and illuminates the eye E (fundus Ef). I do. The return light of the observation illumination light from the subject's eye E is refracted by the objective lens 22, passes through the dichroic mirror 46, passes through the hole formed in the central region of the perforated mirror 21, and passes through the dichroic mirror 55. The light is reflected by a mirror 32 via a focusing lens 31. Further, this return light passes through the half mirror 33A, is reflected by the dichroic mirror 33, and is imaged on the light receiving surface of the image sensor 35 by the imaging lens 34. The image sensor 35 detects return light at a predetermined frame rate. The focus (focal position) of the imaging optical system 30 is adjusted so as to match the fundus oculi Ef or the anterior segment.

  Light (photographing illumination light) output from the photographing light source 15 is applied to the fundus oculi Ef through the same path as the observation illumination light. The return light of the imaging illumination light from the eye E is guided to the dichroic mirror 33 through the same path as the return light of the observation illumination light, passes through the dichroic mirror 33, is reflected by the mirror 36, and is reflected by the imaging lens 37. An image is formed on the light receiving surface of the image sensor 38.

  A liquid crystal display (LCD) 39 displays a fixation target (fixation target image). A part of the light beam output from the LCD 39 is reflected by the half mirror 33A, reflected by the mirror 32, passes through the imaging focusing lens 31 and the dichroic mirror 55, and passes through the hole of the perforated mirror 21. The light beam that has passed through the hole of the perforated mirror 21 passes through the dichroic mirror 46, is refracted by the objective lens 22, and is projected on the fundus Ef.

  By changing the display position of the fixation target image on the screen of the LCD 39, the fixation position of the eye E to be inspected by the fixation target can be changed. As an example of a fixation position, a fixation position for acquiring an image centered on the macula, a fixation position for acquiring an image centered on the optic disc, and a position between the macula and the optic disc. There are a fixation position for acquiring an image at the center, and a fixation position for acquiring an image of a portion (periphery of the fundus) far away from the macula. A graphical user interface (GUI) for specifying at least one of such typical fixation positions can be provided. Further, a GUI or the like for manually moving the fixation position (the display position of the fixation target) can be provided.

  The configuration for presenting the fixation target capable of changing the fixation position to the eye E is not limited to a display device such as an LCD. For example, a fixation matrix in which a plurality of light emitting units (light emitting diodes or the like) are arranged in a matrix (array) can be employed instead of a display device. In this case, the fixation position of the eye E to be inspected by the fixation target can be changed by selectively lighting the plurality of light emitting units. As another example, one or more movable light emitting units can generate a fixation target whose fixation position can be changed.

  The alignment optical system 50 generates an alignment index used for alignment of the optical system with the eye E. The alignment light output from the light emitting diode (LED) 51 passes through the stop 52, the stop 53, and the relay lens 54, is reflected by the dichroic mirror 55, passes through the hole of the perforated mirror 21, and passes through the dichroic mirror 46. The light is transmitted and projected to the eye E through the objective lens 22. Return light (corneal reflected light or the like) of the alignment light from the eye E is guided to the image sensor 35 through the same path as the return light of the observation illumination light. Manual alignment or automatic alignment can be performed based on the received light image (alignment index image).

  As in the related art, the alignment index image of the present example includes two bright spot images whose positions change depending on the alignment state. When the relative position between the subject's eye E and the optical system changes in the xy directions, the two bright spot images are displaced integrally in the xy directions. When the relative position between the eye E and the optical system changes in the z direction, the relative position (distance) between the two bright spot images changes. When the distance between the subject's eye E and the optical system in the z-direction matches the predetermined working distance, the two bright spot images overlap. When the position of the eye E and the position of the optical system match in the xy directions, two bright spot images are presented in or near a predetermined alignment target. When the distance between the subject's eye E and the optical system in the z direction matches the working distance, and the position of the subject's eye E and the position of the optical system match in the xy directions, the two bright spot images overlap and are aligned. Presented in the target.

  In the automatic alignment, the data processing unit 230 detects the positions of the two bright spot images, and the main control unit 211 controls a moving mechanism 150 described below based on the positional relationship between the two bright spot images and the alignment target. . In the manual alignment, the main control unit 211 causes the display unit 241 to display two bright spot images together with the observation image of the eye E, and the user uses the operation unit 242 while referring to the two displayed bright spot images. To operate the moving mechanism 150.

  The focus optical system 60 generates a split index used for focus adjustment on the eye E. The focusing optical system 60 is moved along the optical path (illumination optical path) of the illumination optical system 10 in conjunction with the movement of the imaging focusing lens 31 along the optical path (illumination optical path) of the imaging optical system 30. The reflection bar 67 is inserted into and removed from the illumination optical path. When performing the focus adjustment, the reflection surface of the reflection bar 67 is arranged obliquely in the illumination optical path. Focus light output from the LED 61 passes through a relay lens 62, is split into two light beams by a split indicator plate 63, passes through a two-hole aperture 64, is reflected by a mirror 65, and is reflected by a condensing lens 66 on a reflecting rod 67. Is once imaged on the reflecting surface of and is reflected. Further, the focus light is reflected by the aperture mirror 21 via the relay lens 20, passes through the dichroic mirror 46, and is projected on the eye E through the objective lens 22. The return light of the focus light from the eye E to be inspected (the fundus reflection light or the like) is guided to the image sensor 35 through the same path as the return light of the alignment light. Manual focusing or auto-focusing can be performed based on the received light image (split index image).

  The diopter correction lenses 70 and 71 can be selectively inserted into the photographing optical path between the perforated mirror 21 and the dichroic mirror 55. The diopter correction lens 70 is a plus lens (convex lens) for correcting intensity hyperopia. The diopter correction lens 71 is a minus lens (concave lens) for correcting strong myopia.

  The dichroic mirror 46 combines the fundus imaging optical path and the OCT optical path (measurement arm). The dichroic mirror 46 reflects light in a wavelength band used for OCT and transmits light for fundus imaging. The measurement arm is provided with a collimator lens unit 40, a retroreflector 41, an aberration correction device 47, a dispersion compensation member 42, an OCT focusing lens 43, an optical scanner 44, and a relay lens 45 in this order from the OCT unit 100 side. .

  The retro-reflector 41 can be moved in the direction of the arrow shown in FIG. 1, thereby changing the length of the measuring arm. The change of the measurement arm length is used for, for example, optical path length correction according to the axial length of the eye, adjustment of the interference state, and the like.

  The dispersion compensating member 42 works together with the dispersion compensating member 113 (described later) disposed on the reference arm to match the dispersion characteristics of the measurement light LS and the reference light LR.

  The OCT focusing lens 43 is moved along the measurement arm to adjust the focus of the measurement arm. The movement of the photographing focusing lens 31, the movement of the focusing optical system 60, and the movement of the OCT focusing lens 43 can be controlled in a coordinated manner.

  The optical scanner 44 is disposed substantially at a position optically conjugate with the pupil of the eye E. The optical scanner 44 deflects the measurement light LS guided by the measurement arm. The optical scanner 44 is a galvano scanner capable of two-dimensional scanning including, for example, a galvanomirror for scanning in the x direction and a galvanomirror for scanning in the y direction.

  The aberration correction device 47 is a device for correcting aberration caused by various objects located on the path of the measurement light LS. This aberration includes not only the aberration caused by the eye E to be examined, but also the aberration (intrinsic aberration) caused by the elements constituting the measurement arm.

  In consideration of the fact that the intrinsic aberration is substantially constant, an aberration correction device for correcting this may be provided separately from the aberration correction device 47. Further, when an optical element (group) that can be arranged on the measurement arm and retracted therefrom is provided, as in the attachment for the anterior segment OCT described above, when the optical element (group) is used. The aberration correction device corresponding to the intrinsic aberration and the aberration correction device corresponding to the intrinsic aberration when not in use may be separately provided, or a single aberration that can switch the correction state between when in use and when not in use A correction device may be provided.

  Thus, the aberration correction device 47 is used to correct at least the aberration caused by the eye E. The aberration correction device 47 may be, for example, a deformable mirror (variable shape mirror) or a spatial phase modulator.

  As disclosed in Patent Literature 3, a deformable mirror includes a film-like mirror having a deformable reflecting surface and a plurality of actuators two-dimensionally arranged facing a surface on the back side of the reflecting surface. Including. By selectively driving these actuators, the shape of the reflection surface of the film mirror changes. The driving of each actuator is controlled by the main control unit 211.

  As also disclosed in Patent Document 3, the spatial phase modulator is typically a reflection type modulator using a liquid crystal element, and is selectively used for a plurality of electrodes arranged two-dimensionally. , The orientation of the liquid crystal molecules is locally changed. Thereby, the global refractive index distribution changes, and spatial phase modulation is enabled. The voltage control for each electrode is performed by the main control unit 211.

  The device that can be used as the aberration correction device 47 is not limited to a reflection-type wavefront correction device such as a deformable mirror or a reflection-type spatial phase modulator, but may be a refraction-type device.

  As an example of the refractive aberration correction device, there is a device disclosed in Japanese Laid-Open Patent Publication No. 2010/007665 (FIGS. 17 and 18). This aberration correction device has a transparent electrode divided into a plurality of regions in which a pattern symmetrical to a straight line in a tangential direction (or a radial direction) is formed, and is used to correct coma aberration symmetrical to the straight line. Can be

  In addition to these examples, any device such as a liquid lens (for example, a liquid lens disclosed in Japanese Patent Application Laid-Open No. 2009-037711), two relatively rotatable cylinder lenses, and a focus mechanism may be used to correct aberration. It can be applied as the device 47.

<OCT unit 100>
As illustrated in FIG. 2, the OCT unit 100 is provided with an optical system for applying the swept source OCT. This optical system includes an interference optical system. This interference optical system divides light from a wavelength-variable light source (wavelength-swept light source) into measurement light and reference light, and superimposes the return light of the measurement light from the eye E and the reference light via the reference optical path. Together, interference light is generated, and this interference light is detected. The detection result (detection signal) obtained by the interference optical system is a signal representing the spectrum of the interference light, and is sent to the arithmetic and control unit 200.

  The light source unit 101 includes, for example, a near-infrared tunable laser that changes the wavelength of emitted light at high speed. The light L0 output from the light source unit 101 is guided to a polarization controller 103 by an optical fiber 102, and its polarization state is adjusted. Further, the light L0 is guided to the fiber coupler 105 by the optical fiber 104 and split into the measurement light LS and the reference light LR. The optical path of the measurement light LS is called a measurement arm or the like, and the optical path of the reference light LR is called a reference arm or the like.

  The reference light LR is guided to a collimator 111 by an optical fiber 110, converted into a parallel light beam, and guided to a retroreflector 114 via an optical path length correction member 112 and a dispersion compensation member 113. The optical path length correction member 112 acts to match the optical path length of the reference light LR with the optical path length of the measurement light LS. The dispersion compensating member 113 works together with the dispersion compensating member 42 arranged on the measurement arm to match the dispersion characteristics between the reference light LR and the measurement light LS. The retro-reflector 114 is movable along the optical path of the reference light LR incident thereon, whereby the length of the reference arm is changed. The change of the reference arm length is used, for example, for correcting the optical path length according to the axial length of the eye and adjusting the interference state.

  The reference light LR that has passed through the retroreflector 114 passes through the dispersion compensating member 113 and the optical path length correcting member 112, is converted from a parallel light beam into a focused light beam by the collimator 116, and is incident on the optical fiber 117. The reference light LR that has entered the optical fiber 117 is guided to the polarization controller 118 to adjust its polarization state, is guided to the attenuator 120 through the optical fiber 119, adjusts its light amount, and is transmitted to the fiber coupler 122 through the optical fiber 121. Be guided.

  On the other hand, the measurement light LS generated by the fiber coupler 105 is guided by the optical fiber 127 and is converted into a parallel light flux by the collimator lens unit 40, and the retroreflector 41, the aberration correction device 47, the dispersion compensation member 42, the OCT focusing lens The light is reflected by the dichroic mirror 46 via the optical scanner 43 and the relay lens 45, refracted by the objective lens 22, and projected to the eye E to be examined. The measurement light LS is scattered and reflected at various depth positions of the eye E. The return light of the measurement light LS from the subject's eye E travels in the same path as the outward path in the opposite direction, is guided to the fiber coupler 105, and reaches the fiber coupler 122 via the optical fiber 128.

  The fiber coupler 122 generates interference light by superimposing the measurement light LS input via the optical fiber 128 and the reference light LR input via the optical fiber 121. The fiber coupler 122 generates a pair of interference lights LC by splitting the generated interference light at a predetermined split ratio (for example, 1: 1). The pair of interference lights LC is guided to the detector 125 through the optical fibers 123 and 124, respectively.

  The detector 125 includes, for example, a balanced photodiode. The balanced photodiode has a pair of photodetectors that respectively detect a pair of interference lights LC, and outputs a difference between a pair of detection results obtained by these. The detector 125 sends this output (detection signal) to a data acquisition system (DAQ) 130.

  The data collection system 130 is supplied with a clock KC from the light source unit 101. The clock KC is generated in the light source unit 101 in synchronization with the output timing of each wavelength swept within a predetermined wavelength range by the variable wavelength light source. The light source unit 101, for example, splits the light L0 of each output wavelength to generate two split lights, optically delays one of these split lights, synthesizes these split lights, and converts the obtained synthesized light. The clock KC is generated based on the detection result. The data collection system 130 performs sampling of the detection signal input from the detector 125 based on the clock KC. The data collection system 130 sends the result of this sampling to the arithmetic and control unit 200.

  In this example, both an element for changing the measurement arm length (for example, the retroreflector 41) and an element for changing the reference arm length (for example, the retroreflector 114 or the reference mirror) are provided. However, only one element may be provided. The element for changing the difference (optical path length difference) between the measurement arm length and the reference arm length is not limited to these, and may be any element (optical member, mechanism, etc.).

<Control and processing systems>
3 and 4 show configuration examples of a control system and a processing system of the ophthalmologic photographing apparatus 1. FIG. The control unit 210, the image construction unit 220, and the data processing unit 230 are provided in the arithmetic and control unit 200, for example. The ophthalmologic photographing apparatus 1 may include a communication device for performing data communication with an external device. The ophthalmologic photographing apparatus 1 may include a drive device (reader / writer) for performing a process of reading data from a recording medium and a process of writing data to a recording medium.

<Control unit 210>
The control unit 210 performs various controls. Control unit 210 includes a main control unit 211 and a storage unit 212. Further, as shown in FIG. 4, the control unit 210 of the present embodiment includes a scan control unit 213, a focus control unit 214, and an aberration correction control unit 215.

<Main control unit 211>
The main control unit 211 includes a processor and controls each element of the ophthalmologic imaging apparatus 1 (including the elements illustrated in FIGS. 1 to 4). The main control unit 211 is realized by cooperation between hardware including a processor and control software.

  The main control unit 211 can operate the scan control unit 213 and the focus control unit 214 in cooperation (synchronously). Thus, the OCT scan and the focus adjustment are performed cooperatively (synchronously).

  Under the control of the main control unit 211, the imaging and focusing drive unit 31A moves the imaging and focusing lens 31 arranged in the imaging optical path and the focusing optical system 60 arranged in the illumination optical path. The retro-reflector (RR) drive unit 41A moves the retro-reflector 41 provided on the measurement arm under the control of the main control unit 211. The OCT focusing drive unit 43A moves the OCT focusing lens 43 arranged on the measurement arm under the control of the main control unit 211 (focus control unit 214). The optical scanner 44 provided on the measurement arm operates under the control of the main control unit 211 (scan control unit 213). The aberration correction device 47 operates under the control of the main control unit 211 (the aberration correction control unit 215). The retro-reflector (RR) driving unit 114A moves the retro-reflector 114 disposed on the reference arm under the control of the main control unit 211. Each of the above-described driving units includes an actuator such as a pulse motor that operates under the control of the main control unit 211.

  The moving mechanism 150 moves at least the fundus camera unit 2 three-dimensionally, for example. In a typical example, the moving mechanism 150 includes an x stage movable in the ± x direction (lateral direction), an x moving mechanism that moves the x stage, and a y stage movable in the ± y direction (vertical direction). , A y stage that moves the y stage, a z stage that can move in the ± z direction (depth direction), and a z stage mechanism that moves the z stage. Each of these moving mechanisms includes an actuator such as a pulse motor that operates under the control of the main control unit 211.

<Storage unit 212>
The storage unit 212 stores various data. The data stored in the storage unit 212 includes an OCT image, a fundus image, eye information to be examined, control parameters, and the like.

  The subject eye information includes subject information such as a patient ID and a name, left eye / right eye identification information, electronic medical record information, and the like.

  The control parameters include, for example, parameters (scan control parameters) used for OCT scan control and parameters (focus control parameters) used for focus (focal position) control.

  The scan control parameter is a parameter indicating the content of control on the optical scanner 44. Examples of the scan control parameters include a parameter indicating a scan pattern, a parameter indicating a scan speed, and a parameter indicating a scan interval. The scan speed is defined as, for example, the repetition rate of A-scan. The scan interval is defined as, for example, an interval between adjacent A scans, that is, an arrangement interval of scan points. The scan pattern will be described later.

  The focus control parameter is a parameter indicating the content of control on the OCT focus driving unit 43A. Examples of the focus control parameters include a parameter indicating the focal position of the measurement arm, a parameter indicating the moving speed of the focal position, a parameter indicating the moving acceleration of the focal position, and the like. The parameter indicating the focal position is, for example, a parameter indicating the position of the OCT focusing lens 43. The parameter indicating the moving speed of the focal position is, for example, a parameter indicating the moving speed of the OCT focusing lens 43. The parameter indicating the moving acceleration of the focal position is, for example, a parameter indicating the moving acceleration of the OCT focusing lens 43. The moving speed may or may not be constant. The same applies to the movement acceleration.

<Aberration map 219>
The storage unit 212 stores the aberration map 219. The aberration map 219 is used by the aberration correction control unit 215 to control the aberration correction device 47. The aberration map 219 is acquired before the OCT scan with aberration correction is applied, and is stored in the storage unit 212.

  The aberration map 219 defines an aberration correction amount in at least a part of an application area (scan area) of the OCT scan. An area in which the aberration correction amount is defined may be referred to as a specific area. The specific area may be the entire scan area or only a part thereof.

  The scan area is an area set in advance, and has, for example, a predetermined shape and a predetermined size. The shape of the scan area is, for example, rectangular or circular, and is typically set according to the scan pattern. The rectangular scan area is adopted, for example, when a raster scan (three-dimensional scan) including a plurality of B scans arranged in parallel to each other is applied. The circular scan area is adopted, for example, when any of a spiral scan, a concentric scan, and a radial scan in which a plurality of B scans in different directions are arranged at equal angular intervals is applied.

  For example, a two-dimensional coordinate system (scan coordinate system) for expressing a scan position is defined in the scan area. The scan position can be said to be, for example, an A scan application target position or a measurement target LS projection target position. The scan coordinate system may be an xy coordinate system in the xyz coordinate system (three-dimensional coordinate system) shown in FIG. In addition, a two-dimensional coordinate system different from the xy coordinate system may be set as the scan coordinate system in consideration of the fact that the size of the scan area changes according to the eye axis length and diopter of the eye E. Hereinafter, it is assumed that magnification correction based on the axial length or the like is applied, and the scan coordinate system is an xy coordinate system.

  Assuming that the coordinates of a certain scan position are (x, y), the aberration correction amount W (x, y) is associated with this scan position. The aberration map 219 is a map in which the aberration correction amount W (x, y) is associated with each scan position (x, y) in the specific area. In other words, the aberration map 219 indicates the distribution of the amount of aberration correction in the specific area.

  In the above example, a two-dimensional coordinate system is used to define the scan position, but the definition of the scan position is not limited to this. For example, parameters relating to an optical scanner that deflects measurement light for an OCT scan can be used to define the scan position. In the present embodiment, a parameter indicating the direction of the deflection mirror (galvano mirror) included in the optical scanner 44 or a parameter included in a signal for controlling the optical scanner 44 can be used for defining the scan position. is there.

  In the present embodiment, the scan area may be the same as a wide-angle OCT scan application area described later. Considering that the influence of the aberration is large in the peripheral portion of the fundus, the aberration correction based on the aberration map 219 is more effective as the scan area becomes larger. That is, the aberration correction of the present embodiment is effective in a wide-angle OCT scan.

  The specific area is an area in which the amount of aberration correction is defined in the scan area, and corresponds to at least a part of the scan area.

  When the scan area includes at least a part of the wide-angle OCT scan applicable area, the specific area may include at least a part of the wide-angle OCT scan applicable area. Typically, the specific area includes at least a part of a peripheral area (described later) in the wide-angle OCT scan application area, and more typically includes the entire peripheral area. This is to correct a large aberration in the peripheral portion of the fundus.

  The aberration map 219 is created, for example, according to the aberration distribution in the living eye. The aberration map 219 may include an aberration correction amount distribution obtained from a standard eye aberration distribution. Alternatively, the aberration map 219 may include an aberration correction amount distribution obtained from an aberration distribution statistically obtained by measuring a large number of living eyes. The aberration correction amount at each scan position is, for example, an amount for reducing the aberration at the scan position, and typically is an amount for canceling the aberration at the scan position. Note that the ophthalmologic imaging apparatus 1 may be provided with a wavefront measurement function to create the aberration map before performing the OCT scan.

  Two or more aberration maps can be prepared and these can be selectively used. For example, two or more aberration maps according to the diopter are prepared, such as a myopic aberration map, a hyperopic aberration map, an intensity myopia aberration map, and an intensity hyperopic aberration map, and the diopter of the eye E is prepared. A corresponding aberration map can be selected.

<Scan control unit 213>
The scan control unit 213 controls the optical scanner 44 based on the scan control parameters. The scan control unit 213 may further execute control of the light source unit 101. Details of the processing executed by the scan control unit 213 will be described later. The scan control unit 213 is included in the main control unit 211. The scan control unit 213 is realized by cooperation between hardware including a processor and scan control software.

<Focus control unit 214>
The focus control unit 214 controls the OCT focus driving unit 43A based on the focus control parameters. Details of the processing executed by the focus control unit 214 will be described later. The focus control unit 214 is included in the main control unit 211. The focus control unit 214 is realized by cooperation between hardware including a processor and focus control software.

<Aberration correction control unit 215>
The aberration correction control unit 215 controls the aberration correction device 47 based on the aberration map 219.

  The main control unit 211 causes at least the aberration correction control unit 215 and the scan control unit 213 to cooperate. That is, the main control unit 211 controls the operation of the scan control unit 213 for applying the OCT scan to the scan area (for example, the wide-angle OCT scan application area) based on the scan control parameters, and controls the aberration correction device 47 based on the aberration map 219. The operation is linked with the operation of the aberration correction control unit 215 for performing the correction.

  Thereby, while applying the OCT scan to the region of the fundus oculi Ef corresponding to the specific area, it is possible to apply the aberration correction according to each scan position in the specific area. That is, it is possible to apply the A-scan while appropriately performing the aberration correction on each scan position in the specific area. For a partial area other than the specific area in the scan area, the OCT scan is applied without applying the aberration correction. That is, the A-scan is applied to each scan position outside the specific area without performing the aberration correction.

  The main control unit 211 may cause the aberration correction control unit 215, the scan control unit 213, and the focus control unit 214 to cooperate. That is, the main control unit 211 controls the operation of the scan control unit 213 for applying the OCT scan to the scan area (for example, the wide-angle OCT scan application area) based on the scan control parameters, and controls the aberration correction device 47 based on the aberration map 219. The operation of the aberration correction control unit 215 for performing the operation and the operation of the focus control unit 214 for controlling the OCT focus driving unit 43A based on the focus control parameters can be linked.

  Thereby, while applying the OCT scan to the area of the fundus oculi Ef corresponding to the specific area, it is possible to apply the aberration correction and the focus adjustment according to each scan position in the specific area. That is, it is possible to apply the A-scan while appropriately performing the aberration correction and the focus adjustment on each scan position in the specific area. For a partial area other than the specific area in the scan area, the OCT scan is applied without applying the aberration correction and the focus adjustment, or the focus adjustment and the OCT scan are applied without applying the aberration correction. That is, the A-scan is applied to each scan position outside the specific area without performing at least aberration correction.

  When two or more aberration maps are stored in the storage unit 212, the aberration correction control unit 215 determines, for example, the position of the imaging focusing lens 31 (or the OCT focusing lens 43) after alignment and focus adjustment, and diopter. The diopter of the eye E to be inspected is obtained based on whether or not the correction lenses 70 and 71 are used, and an aberration map corresponding to the diopter of the eye E can be selected from two or more aberration maps. Alternatively, the aberration correction control unit 215 acquires the diopter of the eye E from medical information (such as an electronic medical record) of the subject, and converts the aberration map corresponding to the diopter of the eye E into two or more aberration maps. You can choose from. The aberration correction control unit 215 controls the aberration correction device 47 based on an aberration map selected from two or more aberration maps.

<Image construction unit 220>
The image construction unit 220 includes a processor, and forms OCT image data of the fundus oculi Ef based on a signal (sampling data) input from the data acquisition system 130. The OCT image data is, for example, B-scan image data (two-dimensional tomographic image data).

  The processing for forming OCT image data includes noise removal (noise reduction), filter processing, fast Fourier transform (FFT), and the like, similarly to the conventional Fourier domain OCT. In the case of another type of OCT apparatus, the image construction unit 220 executes a known process according to the type.

  The image construction unit 220 forms three-dimensional data of the fundus oculi Ef based on the signal input from the data collection system 130. The three-dimensional data is three-dimensional image data representing a three-dimensional area (volume) of the fundus oculi Ef. The three-dimensional image data means image data in which the positions of pixels are defined by a three-dimensional coordinate system. Examples of three-dimensional image data include stack data and volume data.

  The stack data is image data obtained by three-dimensionally arranging a plurality of tomographic images obtained along a plurality of scan lines based on a positional relationship between the scan lines. That is, the stack data is an image obtained by expressing a plurality of tomographic images originally defined by individual two-dimensional coordinate systems in one three-dimensional coordinate system (that is, embedding them in one three-dimensional space). Data. Alternatively, the stack data is obtained by three-dimensionally arranging a plurality of A-scan data obtained for each of a plurality of two-dimensionally arranged scan points (scan point arrays) based on the positional relationship between these scan points. Image data.

  Volume data is image data in which voxels arranged three-dimensionally are pixels, and is also called voxel data. The volume data is formed by applying interpolation processing, voxelization processing, or the like to stack data.

  The image construction unit 220 renders the three-dimensional image data to form a display image. Examples of applicable rendering methods include volume rendering, surface rendering, maximum intensity projection (MIP), minimum intensity projection (MinIP), and multi-section reconstruction (MPR).

  The image construction unit 220 can form an OCT front image (OCT en-face image) based on three-dimensional image data. For example, the image construction unit 220 can construct projection data by projecting the three-dimensional image data in the z direction (A line direction, depth direction). Further, the image construction unit 220 can construct a shadowgram by projecting a part of the three-dimensional image data in the z direction.

  Partial three-dimensional image data projected to construct a shadowgram is set using, for example, segmentation. The segmentation is a process for specifying a partial area in an image. Typically, the segmentation is used to specify an image region corresponding to a predetermined tissue of the fundus oculi Ef. The segmentation is performed by, for example, the image construction unit 220 or the data processing unit 230.

  The ophthalmologic imaging apparatus 1 may be capable of performing OCT-Angiography. OCT angiography is an imaging technique for constructing an image in which retinal blood vessels and choroidal blood vessels are emphasized (for example, see Japanese Patent Application Publication No. 2015-515894). Generally, the fundus tissue (structure) does not change with time, but the blood flow portion inside the blood vessel changes with time. In OCT angiography, an image is generated by emphasizing a portion (blood flow signal) where such a temporal change exists. Note that OCT angiography is also called OCT motion contrast imaging or the like. Images acquired by OCT angiography are called angiographic images, angiograms, motion contrast images, and the like.

  When OCT angiography is performed, the ophthalmologic imaging apparatus 1 repeatedly scans the same area of the fundus oculi Ef a predetermined number of times. For example, scanning can be repeatedly performed along a locus between two points on a predetermined scan pattern (for example, a spiral scan pattern). The image builder 220 can build a motion contrast image from the data set collected by the data collection system 130 in the repetitive scan. This motion contrast image is an angiographic image in which the temporal change of the interference signal caused by the blood flow in the fundus oculi Ef is emphasized and imaged. Typically, OCT angiography is applied to a three-dimensional region of the fundus oculi Ef, and an image representing a three-dimensional distribution of blood vessels of the fundus oculi Ef is obtained.

  When the OCT angiography is performed, the image constructing unit 220 can construct any two-dimensional angiographic image data and / or any pseudo three-dimensional angiographic image data from the three-dimensional angiographic image data. It is. For example, the image construction unit 220 can construct two-dimensional angiographic image data representing an arbitrary cross section of the fundus oculi Ef by applying multi-sectional reconstruction to the three-dimensional angiographic image data.

  The image construction unit 220 is realized by cooperation between hardware including a processor and image construction software.

<Data processing unit 230>
The data processing unit 230 includes a processor and applies various types of data processing to the image of the eye E. For example, the data processing unit 230 is realized by cooperation between hardware including a processor and data processing software.

  The data processing unit 230 can perform registration (registration) between two images acquired for the fundus oculi Ef. For example, the data processing unit 230 can perform registration between the three-dimensional image data acquired by OCT and the front image acquired by the fundus camera unit 2. Further, the data processing unit 230 can perform registration between two OCT images acquired by OCT. Further, the data processing unit 230 can perform registration between the two front images acquired by the fundus camera unit 2. In addition, registration can be applied to the analysis result of the OCT image or the analysis result of the front image. The registration can be performed by a known method, and includes, for example, feature point extraction and affine transformation.

  As illustrated in FIG. 4, the data processing unit 230 of the present embodiment includes a parameter setting unit 231, a movement detection unit 232, and an aberration map creation unit 233.

<Parameter setting unit 231>
The parameter setting unit 231 sets a focus control parameter based on the OCT image of the fundus oculi Ef acquired in advance. This OCT image (preliminary image) is used to detect a rough shape of an application area of the wide-angle OCT scan, and a focus control parameter is set based on the detected shape.

  The ophthalmologic photographing apparatus 1 can acquire an OCT image used for setting a focus control parameter. For example, the ophthalmologic imaging apparatus 1 can apply a preliminary OCT scan to the eye E before applying the wide-angle OCT scan to the eye E.

  The preliminary OCT scan is performed so as to pass through both the central region and the peripheral region of the wide-angle OCT scan application area. For example, in a preparatory OCT scan for a wide-angle OCT scan of the fundus oculi Ef, the macula area (and its surrounding area) is set as the central area of the fundus oculi Ef, and an area at least a predetermined distance from the macula is set as the peripheral area can do. In a preliminary OCT scan for a wide-angle OCT scan of the anterior segment, a vertex of the cornea and a region near the vertex are set as the central region of the anterior segment, and a region that is at least a predetermined distance from the vertex of the cornea is a peripheral region. Can be set to More generally, it is possible to set the eye axis of the eye E to be examined and a region in the vicinity thereof as a central region, and set a region apart from the eye axis by a predetermined distance or more as a peripheral region.

  The pattern of the preparatory OCT scan may be a scan pattern including a large number of scan points such as a three-dimensional scan (raster scan), but the purpose of the preparatory OCT scan is to define a rough shape of the wide-angle OCT scan application area. In consideration of grasping, a relatively simple scan pattern such as B scan (line scan), cross scan, and radial scan is sufficient.

  The image construction unit 220 constructs a preliminary image from data collected by the preliminary OCT scan. The preliminary images typically include one or more B-scan images representing one or more cross-sections of the central region and one or more cross-sections of the peripheral region of the wide-angle OCT scan application area.

  In the following example, the outer edge of the central region and the outer edge and the inner edge of the peripheral region are all circular, but the shape of the central region and the shape of the peripheral region are not limited thereto. For example, either the outer edge of the central area and the outer edge or the inner edge of the peripheral area may be rectangular, and may have any shape. Further, the outer edge shape and the inner edge shape of the peripheral edge region may be the same or may be different from each other.

  An example of the preliminary OCT scan shown in FIG. 5A is one B scan 330 that passes through a central region 310 including the macula Em of the fundus oculi Ef and a peripheral region 320 (region indicated by oblique lines) away from the macula Em. . Symbol Ed indicates the optic disc. In this example, one B-scan image representing the section to which the B-scan 330 has been applied is obtained. The B-scan image of the present example shows a relative relationship between the depth position (z position) of the central region 310 and the depth position of the peripheral region 320. In this example, a relative depth positional relationship between the center region 310 and the peripheral region 320 is obtained only in the direction in which the B scan 330 is applied.

  An example of the preparatory OCT scan shown in FIG. 5B is two B scans 341 and 342 each passing through a central region 310 and a peripheral region 320. The two B scans 341 and 342 are orthogonal to each other. That is, the preparatory OCT scan of this example is a cross scan. In this example, a B-scan image representing a section to which the B-scan 341 has been applied and a B-scan image representing a section to which the B-scan 342 has been applied are obtained. Each of the two B-scan images of the present example represents a relative relationship between the depth position (z position) of the central region 310 and the depth position of the peripheral region 320. In this example, the relative depth position relationship between the center region 310 and the peripheral region 320 in the direction in which the B-scan 341 is applied and the direction in which the B-scan 342 is applied, that is, in two directions orthogonal to each other. can get.

  Although illustration is omitted, when a radial scan (a plurality of B scans arranged at equal angular intervals) is applied as a preparatory OCT scan, the center region and the peripheral region are arranged in a plurality of directions arranged at equal angular intervals from each other. Is obtained. Also, although not shown, when a three-dimensional scan (for example, a raster scan) is applied as a preliminary OCT scan, the relative depth position between the center region and the peripheral region in any direction on the xy plane A relationship is obtained. Even when another scan pattern is applied, a relative depth position relationship between the center region and the peripheral region can be obtained in one or more directions according to the scan pattern.

  As described above, the pattern of the preparatory OCT scan determines the content (direction and the like) and the amount (angle interval and the like) of the information acquired as the relative depth position relationship. Conversely, the pattern of the preparatory OCT scan can be determined according to the content and amount of information desired to be acquired as the relative depth position relationship. The determination of the preliminary OCT scan pattern is performed, for example, in advance or for each inspection.

  The data collected by the preliminary OCT scan is sent to the image construction unit 220, and a preliminary image is constructed. The parameter setting unit 231 sets one or more focus control parameters based on the preliminary image. As described above, the focus control parameter is a parameter indicating the content of control for the OCT focus driving unit 43A, and examples thereof include a parameter indicating the focus position of the measurement arm, a parameter indicating the moving speed of the focus position, and a focus position. There is a parameter indicating the moving acceleration of.

  An example of a process executed by the parameter setting unit 231 will be described. An example of a preliminary image is shown in FIG. 6A. The preliminary image G is, for example, an image constructed from data collected by the B scan 330 illustrated in FIG. 5A (or the B scan 341 illustrated in FIG. 5B or a similar B scan). An area having a contour indicated by a dotted line denoted by reference numeral 310 corresponds to an intersection area (common area) between the central area 310 and the B-scan 330 shown in FIG. 5A. The region indicated by oblique lines with the reference numeral 320 corresponds to the intersection region (common region) between the peripheral region 320 and the B scan 330 shown in FIG. 5A. Note that the preparatory image G has two peripheral regions 320. The symbol Em is an image region of the macula, and the symbol Ed is an image region of the optic disc.

The parameter setting unit 231 analyzes the central region 310 of the preliminary image G, detects the macula region Em, and specifies its depth position (z coordinate). For this purpose, the parameter setting unit 231 performs, for example, segmentation for specifying the image region of the inner limiting membrane (ILM), shape analysis for detecting the macula region Em from the specified shape (dent) of the inner limiting membrane region, and detection. Calculating the z-coordinate of the pixel at the representative point of the obtained macular region Em. The representative point of the macula region Em may be, for example, the center of the macula (fovea, the deepest part of the dent). The z coordinate of the macula center obtained by this example and z ₁ (see FIG. 6B). Note that the part where the z coordinate is specified is not limited to the center of the macula, and may be any representative point in the central region 310.

Further, the parameter setting unit 231 analyzes the peripheral region 320 of the preliminary image G, detects an image region of a predetermined tissue (for example, an inner limiting membrane), and specifies a depth position (z coordinate) thereof. For that purpose, the parameter setting unit 231 includes, for example, a segmentation for specifying an image region of a predetermined tissue, and a process for obtaining az coordinate of a pixel at a representative point of the specified image region. The representative point of the image region of the predetermined tissue may be, for example, the center position of the peripheral region 320 in the B-scan direction or the end point of the peripheral region 320. The z-coordinate of the boundary layer among the respective center positions of the two peripheral regions 320 of the preparatory image G is obtained by the present example in the case of the representative point and z ₂₁ and z ₂₂ (see FIG. 6C).

Further, the parameter setting unit 231 sets a focus control parameter based on the z coordinate (z ₁ ) of the representative point of the central area 310 and the z coordinate (z ₂₁ , z ₂₂ ) of the representative point of the peripheral area 320. .

For example, the parameter setting unit 231 determines the position of the OCT focusing lens 43 corresponding to the z coordinate (z ₁ ) of the representative point of the central area 310 and the z coordinate (z ₂₁ and z ₂₂ of the representative point of the peripheral area 320, respectively). ), The position of the OCT focusing lens 43 can be obtained. The position of the OCT focusing lens 43 corresponds to the focal position of the measurement arm. This example can be said to be a process for obtaining the absolute position of the OCT focusing lens 43. The processing of this example includes, for example, a coherence gate position (arm length, position of the retroreflector 41, position of the retroreflector 114) when the preliminary image G is acquired, and a scale of the z axis (for example, per pixel). Distance).

The parameter setting unit 231 determines the position (focal position) of the OCT focusing lens 43 corresponding to the z coordinate (z ₁ ) of the representative point of the central area 310 and the z coordinate (z ₂₁ and z ₂₂ ) of the representative point of the peripheral area 320. Of the OCT focusing lens 43 (focal position) corresponding to (i. In other words, this example can be said to be a process for obtaining the relative position of the OCT focusing lens 43. The processing of this example is executed based on, for example, the scale of the z-axis.

The parameter setting unit 231 determines the position (focal position) of the OCT focusing lens 43 corresponding to the z coordinate (z ₁ ) of the representative point of the central area 310 and the z coordinate (z ₂₁ and z ₂₂ ) of the representative point of the peripheral area 320. ), The focus position change range including the position (focus position) of the OCT focusing lens 43 corresponding to (i). The focus position change range is a range of the focus position changed by the focus control, and is defined as a moving range of the OCT focusing lens 43, for example. The processing of this example is executed based on, for example, the coherence gate position when the preliminary image G is acquired and the scale of the z-axis.

  The parameter setting unit 231 can set the speed at which the focus position of the measurement arm moves. The processing of this example is executed based on, for example, the absolute position or relative position of the OCT focusing lens 43 described above, or based on the moving range of the OCT focusing lens 43.

  The parameter setting unit 231 can set the acceleration for moving the focal position of the measurement arm. The processing of this example is based on, for example, the absolute position or relative position of the OCT focusing lens 43, based on the moving range of the OCT focusing lens 43, or based on the moving speed of the OCT focusing lens 43. Will be executed.

  When the preparatory image G is obtained, for example, as shown in FIG. 7, the focal position moves in the + z direction from the left peripheral region 320 side toward the central region 310 side, and the focal position moves rightward from the central region 310 side. The parameter setting unit 231 sets the focus control parameter so that the focal position moves in the −z direction as going toward the peripheral region 320 side of.

  The parameter setting unit 231 can set information indicating the relationship between the scan control parameter and the focus control parameter based on, for example, any of the above-described examples of the focus control parameter.

  As a premise, a scan pattern for a wide-angle OCT scan is set. The wide-angle OCT scan pattern is set, for example, in advance or for each inspection.

  In the present embodiment, the wide-angle OCT scan pattern includes a scan pattern including a continuous first partial pattern for the central region of the wide-angle OCT scan application area and a continuous second partial pattern for the peripheral region. The first partial pattern is a pattern for continuously scanning at least a part of the central area, and the second partial pattern is a pattern for continuously scanning at least a part of the peripheral area. Here, “continuously scan” means, for example, sequentially scanning a plurality of scan points arranged in a predetermined pattern in accordance with the arrangement order.

  The wide-angle OCT scan pattern may include a curved scan pattern defined by a polar coordinate system having the origin at the center of the wide-angle OCT scan application area. The center of the wide-angle OCT scan application area may be, for example, the center of the macula or another part of the fundus. As described above, the center of the wide-angle OCT scan application area may be defined based on the site or tissue of the eye to be inspected, but may be defined based on the ophthalmologic imaging apparatus 1. For example, the center of the wide-angle OCT scan application area may be defined as a neutral position (neutral direction) of a variable direction mirror (such as a galvanometer mirror) of the optical scanner 44, or may be defined as an optical axis of the measurement arm (optical axis of the objective lens 22). ) May be defined. Examples of curved wide-angle OCT scan patterns defined in a polar coordinate system having the origin at the center of the wide-angle OCT scan application area include a spiral pattern and a concentric pattern.

  When the wide-angle OCT scan pattern is the above-described curved scan pattern, the wide-angle OCT scan pattern is a spiral scan pattern from the center of the wide-angle OCT scan application area to the outer edge (see the spiral scan pattern 510 shown in FIG. 8A). Alternatively, a spiral scan pattern (see spiral scan pattern 520 shown in FIG. 8B) from the outer edge of the wide-angle OCT scan application area toward the center may be used.

  The spiral scan pattern 510 shown in FIG. 8A has the center of the macula in the central region (not shown) as the scan start point, and passes through the peripheral region (not shown) while increasing the radial radius as the declination changes. The scan ends at the outer edge (near).

  The spiral scan pattern 520 shown in FIG. 8B has an outer edge (near) as a scan start point, passes through a peripheral area (not shown) while decreasing a radial radius with a change in declination, and a central area (not shown). To the scan end point set at the center of the macula.

  In each of the spiral scan patterns 510 and 520, the spiral interval is drawn coarser than the actual one for the purpose of illustration. In practice, for example, the intervals between the spirals may be so close that three-dimensional image data can be constructed.

  Some examples of focus control parameters that can be set by the parameter setting unit 231 when the wide-angle OCT scan pattern is the above-described curved scan pattern (for example, a spiral scan pattern) will be described with reference to FIGS. 9A to 9D. .

  Note that the focus control parameters that can be set by the parameter setting unit 231 are not limited to these examples, and may be any focus control parameters that satisfy the conditions required in the present embodiment.

  In the example shown in FIG. 9A, the horizontal axis of the coordinate system indicates the scan position, and the vertical axis indicates the focus position. The scan position on the horizontal axis is defined as N scan point numbers n (n = 0, 1, 2,..., N−1) ordered according to the applied scan pattern. The focal position on the vertical axis is defined as az coordinate. The focus control parameter of FIG. 9A is applicable when a spiral scan pattern from the center of the wide-angle OCT scan application area to the outer edge is employed, for example, like a spiral scan pattern 510 shown in FIG. 8A. Hereinafter, as an example, a description will be given together with the spiral scan pattern 510.

  The first scan position n = 0 in FIG. 9A corresponds to the scan start point (center of the macula) in the spiral scan pattern 510, and the last scan position n = N−1 corresponds to the scan end point (in the spiral scan pattern 510). (A position on the outer edge or a position near the outer edge).

Scan start position n = 0 to the allocation focal position zeta ₁₁ is is set based on the z-coordinate z _1, for example the central region 310 shown in FIG. 6B (e.g. macular center). For example, zeta ₁₁ is either set equal to _{z 1,} or zeta ₁₁ is set substantially equal to _{z 1.}

Focus position zeta ₁₂ assigned to the scanning end position n = N-1 is, for example, at least one of the basis set of z-coordinate _{z 21} and _{z 22} in the peripheral region 320 shown in FIG. 6C. For example, zeta ₁₂ is set equal to _{z 21,} zeta ₁₂ is either set to a value approximately equal to _{z 21,} or zeta ₁₂ is set equal to _{z 22,} zeta ₁₂ is approximately equal to _{z 22} either set to, or, zeta ₁₂ is set to a value obtained from both _{z 21} and _{z 22.} Examples of the case of obtaining both the zeta ₁₂ of z ₂₁ and _{z 22,} calculating the average of _{z 21} and _{z 22 and,} and calculating the weighted average of the _{z 21} and _{z 22, z 21} and z Arbitrary statistical processing can be used, such as selecting the larger value or the smaller value out of ₂₂ .

The focus control parameters shown in FIG. 9A include the coordinates (0, _{１１ 11} ) corresponding to the scan start point and the coordinates (N−1, ζ ₁₂ ) corresponding to the scan end point in the two-dimensional coordinate system (n, z). It can be set as a connected smooth curve (for example, spline curve, Bezier curve).

  The two-dimensional coordinate system (n, z) in the example shown in FIG. 9B is the same as that in the example shown in FIG. 9A. The focus control parameter of FIG. 9B can be applied when a spiral scan pattern from the outer edge to the center of the wide-angle OCT scan application area is adopted, for example, like a spiral scan pattern 520 shown in FIG. 8B. Hereinafter, the example will be described together with the spiral scan pattern 520.

  The first scan position n = 0 in FIG. 9B corresponds to a scan start point (a position on the outer edge or a position near the outer edge) in the spiral scan pattern 520, and the last scan position n = N-1 is a spiral scan pattern. This corresponds to the scan end point (macular center) in the pattern 520.

The focal position _{２１ 21} assigned to the scan start position n = 0 can be set, for example, in the same manner as the focal position _{１２ 12 of} FIG. 9A. The scan end position n = N-1 the focal position zeta ₂₂ assigned to, for example, can be set in the same way as the focal position zeta ₁₁ in Figure 9A.

The focus control parameters shown in FIG. 9B include coordinates (0, _{２１ 21} ) corresponding to the scan start point and coordinates (N−1, _{２２ 22} ) corresponding to the scan end point in the two-dimensional coordinate system (n, z). It can be set as a connected smooth curve (for example, spline curve, Bezier curve).

  The two-dimensional coordinate system (n, z) in the example shown in FIG. 9C is the same as that in the example shown in FIG. 9A. The focus control parameter of FIG. 9C is applicable when a spiral scan pattern from the center of the wide-angle OCT scan application area to the outer edge is employed, for example, like a spiral scan pattern 510 shown in FIG. 8A. Hereinafter, as an example, a description will be given together with the spiral scan pattern 510.

  The first scan position n = 0 in FIG. 9C corresponds to the scan start point (center of the macula) in the spiral scan pattern 510, and the last scan position n = N−1 is the scan end point (the scan end point in the spiral scan pattern 510). (A position on the outer edge or a position near the outer edge).

The focal position _{３１ 31} assigned to the scan position section n = [0, n ₃₁ ] can be set, for example, in the same manner as the focal position _{１１ 11 in} FIG. 9A. The focal position ζ ₃₃ assigned to the scan position section n = [n ₃₂ , N−1] can be set, for example, in the same manner as the focal position ζ _{12 of} FIG. 9A. Further, the focus position _{３２ 32} assigned to the scan position section n = (n ₃₁ , n ₃₂ ) = [n ₃₁ +1, n ₃₂ −1] can be set based on the focus positions _{３１ 31} and _{３３ 33} , for example. is there. Typically, the focal position ζ ₃₂ is obtained by, for example, any statistical processing. Examples of statistics obtained, the average of the zeta ₃₁ and zeta _33, weighted average, larger value of the zeta ₃₁ and zeta ₃₃ between zeta ₃₁ and zeta _33, of the zeta ₃₁ and zeta ₃₃ There is a smaller value.

  Similar to the relationship between the focus control parameter shown in FIG. 9A and the focus control parameter shown in FIG. 9B, the stepwise focus control parameter shown in FIG. 9C can be inverted. The focus control parameter obtained by the inversion can be applied when a spiral scan pattern from the outer edge to the center of the wide-angle OCT scan application area is adopted, for example, like a spiral scan pattern 520 shown in FIG. 8B.

Further, it is possible to modify the focus control parameters shown in FIG. 9C. For example, a smooth curve (for example, a spline curve or a Bezier curve) connecting the coordinates (0, _{３１ 31} ) and the coordinates (n ₃₁ , ζ ₃₂ ) is assigned to the section n = [0, n ₃₁ ] of the scan position. be able to. Further, a smooth curve (for example, a spline curve, a Bezier) connecting the coordinates (n ₃₂ , _{３２ 32} ) and the coordinates (N ζ, _{３３ 33} ) to the section n = [n ₃₂ , N−1] of the scan position. Curve). For example, when a spiral scan pattern from the outer edge to the center of the wide-angle OCT scan application area is adopted as in a spiral scan pattern 520 shown in FIG. 8B, the focus control parameter partially replaced with a curve is used as the focus control parameter. It is possible to invert.

Alternatively, a straight line (oblique line) connecting the coordinates (0, _{３１ 31} ) and the coordinates (n ₃₁ , _{３２ 32} ) can be assigned to the section n = [0, n ₃₁ ] of the scan position. Further, a straight line (oblique line) connecting the coordinates (n ₃₂ , _{３２ 32} ) and the coordinates (N-1, _{３３ 33} ) can be assigned to the section n = [n ₃₂ , N−1] of the scan position. For example, when a spiral scan pattern from the outer edge of the wide-angle OCT scan application area to the center is employed as in a spiral scan pattern 520 shown in FIG. 8B, the focus control parameter partially replaced with oblique lines is used. It is possible to invert.

  The two-dimensional coordinate system (n, z) in the example shown in FIG. 9D is the same as that in the example shown in FIG. 9A. The focus control parameter of FIG. 9D is applicable when a spiral scan pattern from the center of the wide-angle OCT scan application area to the outer edge is employed, for example, like a spiral scan pattern 510 shown in FIG. 8A. Hereinafter, as an example, a description will be given together with the spiral scan pattern 510.

  The first scan position n = 0 in FIG. 9D corresponds to the scan start point (center of the macula) in the spiral scan pattern 510, and the last scan position n = N−1 corresponds to the scan end point (the scan end point in the spiral scan pattern 510). (A position on the outer edge or a position near the outer edge).

The focal position _{４１ 41} assigned to the scan position section n = [0, n ₄₁ ] can be set, for example, in the same manner as the focal position ζ _{11 in} FIG. 9A. The focal position ζ ₄₂ assigned to the scan position section n = [n ₄₂ , N−1] can be set, for example, in the same manner as the focal position _{１２ 12 of} FIG. 9A. Further, the coordinates (n ₄₁ , ζ ₄₁ ) and the coordinates (n ₄₂ , ζ ₄₂ ) are connected to the scan position section n = (n ₄₁ , n ₄₂ ) = [n ₄₁ +1, n ₄₂ -1]. A straight line has been assigned.

  Similar to the relationship between the focus control parameter shown in FIG. 9A and the focus control parameter shown in FIG. 9B, the focus control parameter shown in FIG. 9D can be inverted. The focus control parameter obtained by the inversion can be applied when a spiral scan pattern from the outer edge to the center of the wide-angle OCT scan application area is adopted, for example, like a spiral scan pattern 520 shown in FIG. 8B.

Further, it is possible to modify the focus control parameters shown in FIG. 9D. For example, the scan position section n = (n ₄₁ , n ₄₂ ) = [n ₄₁ +1, n ₄₂ −1] connects the coordinates (n ₄₁ , _{４１ 41} ) and the coordinates (n ₄₂ , _{４２ 42} ) smoothly. Curve (for example, spline curve, Bezier curve) can be assigned. For example, when a spiral scan pattern from the outer edge to the center of the wide-angle OCT scan application area is adopted as in a spiral scan pattern 520 shown in FIG. 8B, the focus control parameter partially replaced with a curve is used as the focus control parameter. It is possible to invert.

  Although the example of the process executed by the parameter setting unit 231 and the example of the focus control parameter created thereby have been described above, these are not intended to be limited, and various modifications are allowed.

  For example, in the example shown in FIG. 6B, the depth position (z coordinate) of one representative point (macular center) in the central region 310 is obtained, and this is used as the depth position of the central region 310. On the other hand, it is possible to determine the depth position of each of two or more points in the central region and determine the depth position of the central region from the determined two or more depth positions. For example, statistical processing can be applied to two or more depth positions to determine the depth position of the central region. The statistical value obtained from two or more depth positions may be, for example, any one of an average value, a weighted average value, an intermediate value, a mode value, a maximum value, and a minimum value. Similar processing can be applied to the case where the depth position of the peripheral area is obtained.

When obtaining two or more depth positions in the central region, instead of calculating a single statistical value from these depth positions and using this as the depth position of the central region as described above, these depth positions are used. , Information representing a change in the depth position in the central region can be obtained. For example, based on these depth positions, a graph (focus control parameter) representing a curved, linear, or stepwise change in the depth position in the central region can be obtained. 9A and 9B are examples of a curve-like change. Although illustration is omitted, as an example of a linear change in the depth position in the central region, the coordinates (0, _{３１ 31} ) and the coordinates (n ₃₁ , _{３２ 32} ) are connected in the two-dimensional coordinate system shown in FIG. 9C. It is possible to find a straight line. Although illustration is omitted, as an example of the stepwise change of the depth position in the central region, in the two-dimensional coordinate system shown in FIG. 9C, the focal position of the focus position is set to n = [0, n ₃₁ ] of the scan position. it is possible to set the focus control parameter whose value varies stepwise from zeta ₃₁ to zeta _32. Similar processing can be applied to the case where the focus control parameter of the peripheral area is obtained.

  As described above, the process of setting the focus control parameter by obtaining two or more depth positions in the center region is performed, for example, when the width of the center region (the length in the direction orthogonal to the z direction) is relatively large. It is considered effective when the change in the depth position in the central region is large (for example, when the difference between the maximum depth position and the minimum depth position in the central region is large). The parameter setting unit 231 may determine the number of points in the central region for which the depth region is determined according to the width of the central region and / or the magnitude of the change in the depth position in the central region. (And position). Similar processing can be applied to the case where the focus control parameter of the peripheral area is obtained.

  In the example described above, the central region (310) and the peripheral region (320) are separated from each other. In other words, in the example described above, an annular (annulus) -shaped intermediate region exists between the outer edge of the central region and the inner edge of the peripheral region. In another example, the outer edge of the central area may coincide with the inner edge of the peripheral area.

  More generally, in the present embodiment, the central region and the peripheral region can be arbitrarily defined. For example, the central region and the peripheral region may be defined according to the site of the fundus. As a specific example, an area centered on a predetermined part of the fundus (for example, the center of the macula) and within a predetermined first distance from the center can be set as the central area. Further, an area that is equal to or longer than a predetermined second distance (which is equal to or longer than the first distance) from the center can be set as the peripheral area. Here, the third distance representing the outer edge of the peripheral area may be further set, or the outer edge of the wide-angle OCT scan application area may be set as the outer edge of the peripheral area. The distance in this example may be a distance at the fundus, a distance calculated optically, or a standard distance obtained from a model eye or clinical data.

  As another definition of the center region and the peripheral region, there is a definition corresponding to the OCT scan. For example, it is possible to set a predetermined first area in the wide-angle OCT scan application area as a center area and set a predetermined second area different from the second area as a peripheral area. Typically, a first area including the center of the wide-angle OCT scan application area is set as a central area, and a second area located outside the first area is set as a peripheral area.

  In the example described above, a scan pattern composed of a curve, such as a spiral scan pattern, is particularly described. However, a scan pattern composed of at least a part of a straight line may be employed. For example, by alternately combining the line scan in the x direction and the line scan in the y direction, a spiral scan pattern composed of a plurality of straight lines can be applied.

  The setting of the wide-angle OCT scan pattern and the focus control parameter (and the scan speed) exemplified above includes the setting of the moving speed and / or the moving acceleration of the focal position. For example, in the focus control parameters exemplified in FIGS. 9A to 9D, the slope of the graph indicating the focus control parameter corresponds to the moving speed, and the rate of change of the slope of the graph corresponds to the moving acceleration. Conversely, it is possible to set the focus control parameter through the setting of the moving speed and / or the moving acceleration of the focal position.

  9A to 9D, the focus position (first focus position) applied to the central region is + z side of the focus position (second focus position) applied to the peripheral region. Located in. That is, the focal length (first focal length) corresponding to the first focal position is set longer than the focal length (second focal length) corresponding to the second focal position. This depends on the shape of the eye to be examined (fundus). However, the first focal length need not be longer than the second focal length.

  The parameter setting unit 231 capable of executing the above processing is realized by cooperation between hardware including a processor and parameter setting software.

<Motion detector 232>
The ophthalmologic photographing apparatus 1 includes a fundus camera unit 2 that repeatedly photographs the eye E and acquires a time-series image. The time-series image acquired by the fundus camera unit 2 is, for example, the above-described observation image.

  The movement detection unit 232 detects the movement of the eye E by analyzing the observation image acquired by the fundus camera unit 2. For example, the movement detection unit 232 analyzes each image included in the observation image, detects a feature point, and obtains a time-series change in the position of the feature point. The feature points may be, for example, the center, center of gravity, and contour of the pupil, and the center, center of gravity, and contour of the iris.

  At least in parallel with the operation of the aberration correction control unit 215, the scan control unit 213 controls the optical scanner 44 and the OCT unit 100 according to the wide-angle OCT scan pattern, and controls the optical scanner 44 based on the output from the movement detection unit 213. Can be controlled. The control of the optical scanner 44 based on the output from the movement detection unit 213 is so-called tracking control.

  The tracking is executed, for example, by the following series of processes disclosed in JP-A-2017-153543. First, the movement detection unit 232 registers any frame (front image) of the observation image acquired by the fundus camera unit 2 as a reference image.

  Further, the movement detection unit 232 obtains a change in the position of the feature point in another frame with respect to the position of the feature point in the reference image. This corresponds to obtaining a time-series change in the position of the feature point, that is, obtaining a displacement between the reference image and another frame. Note that, when the displacement exceeds a threshold value due to blinking or fixation deviation or when the displacement cannot be detected, the movement detection unit 232 can register a frame acquired thereafter as a new reference image. . Further, the method for obtaining the time-series change of the position of the feature point is not limited to this. For example, the displacement of the feature point between two consecutive frames may be sequentially obtained.

  The movement detection unit 232 sends control information for canceling the time-series change to the scan control unit 213 every time a time-series change in the position of the feature point is obtained. At least in parallel with the operation of the aberration correction control unit 215, the scan control unit 213 corrects the direction of the optical scanner 44 based on the sequentially input control information.

  The movement detection unit 232 is realized by cooperation between hardware including a processor and movement detection software.

<Aberration map creation unit 233>
The aberration map creation unit 233 creates an aberration map. The created aberration map (219) is stored in the storage unit 212.

  For example, the aberration map creation unit 233 can create an aberration map based on the OCT image of the fundus oculi Ef. An example of a process of creating an aberration map from an OCT image will be described below with reference to FIG.

  In this example, a wide-angle OCT scan is applied to the fundus oculi Ef by the ophthalmologic photographing apparatus 1 (or another ophthalmologic photographing apparatus) to acquire a wide-angle OCT image, and the shape of the fundus oculi Ef is grasped from the wide-angle OCT image and grasped. An aberration map is created based on the fundus shape and a predetermined fundus shape-aberration database.

  The fundus shape-aberration database is a database representing the relationship between the fundus shape and aberration, and is created by actually performing aberration measurement on eyes having various fundus shapes. The fundus shape-aberration database is stored in the ophthalmologic photographing apparatus 1 or another apparatus, and can be referred to by the aberration map creation unit 233.

  A plurality of B-scan images 600u (u = 1, 2,..., U: U is an integer of 2 or more) shown in FIG. 10 are examples of OCT images obtained by wide-angle OCT scan of the fundus oculi Ef.

  The aberration map creation unit 233 analyzes each B-scan image 600u to determine the shape of the fundus oculi Ef. For this purpose, the aberration map creation unit 233 specifies, for example, a pixel having the maximum luminance from each A-scan image constituting the B-scan image 600u, and thereby determines the position of the fundus oculi Ef at each A-scan position (x, y) (z Position). For example, as shown in FIG. 10, a pixel 610uv having the maximum luminance at each A-scan position is specified (v = 1, 2,..., Vu: Vu: two or more pixels set for each B-scan image 600u). integer). Thereby, the shape (x, y, z) of the fundus oculi Ef depicted in each B-scan image 600u is obtained.

  Instead of specifying the pixel having the maximum luminance, for example, an image of a predetermined fundus tissue may be specified by segmentation. The fundus tissue specified includes the inner limiting membrane, nerve fiber layer, ganglion cell layer, retinal pigment epithelium layer and the like. The method of detecting the position (shape) of the fundus is not limited to these, and any method can be adopted.

  Next, the aberration map creation unit 233 obtains, for example, an aberration (aberration correction amount) corresponding to the z position of the fundus oculi Ef at each A-scan position (x, y) by referring to the fundus shape-aberration database. By performing this processing for a plurality of A-scan positions (x, y), a distribution of aberration correction amounts in an area to which the wide-angle OCT scan is applied can be obtained. This aberration correction amount distribution is used as an aberration map.

  It is not necessary to create an aberration map for the entire area to which the wide-angle OCT scan has been applied. That is, the aberration map may be created only for a part of the area to which the wide-angle OCT scan is applied. For example, it is possible to create an aberration map in which the aberration correction amount is recorded only for a portion where the aberration correction amount is equal to or more than a predetermined threshold. Further, it is possible to create an aberration map in which the aberration correction amount is recorded only for a predetermined region (for example, a peripheral region or a region including a part thereof).

  The created aberration map is stored in the storage unit 212. Here, any of the identification information of the subject and the identification information of the eye E can be associated with the created aberration map. Further, creation date information and the like can be associated with the created aberration map. This makes it possible to use an aberration map for each subject and an aberration map for each eye. The aberration correction control unit 215 reads out the aberration map associated with the input identification information (the subject identification information and the eye identification information) from the storage unit 212 and uses the aberration map.

  The aberration map created by the aberration map creation unit 233 in this manner is not a standard and statistical aberration map, but an individual aberration map created by actually measuring the eye E to be inspected. When both the individual aberration map and the standard aberration map are stored in the storage unit 212, either one may be used in the aberration correction control, but typically, the individual aberration map corresponding to the eye E is An aberration map is selected.

<User interface 240>
The user interface 240 includes a display unit 241 and an operation unit 242. The display unit 241 includes the display device 3. The operation unit 242 includes various operation devices and input devices. The user interface 240 may include a device in which a display function and an operation function are integrated, such as a touch panel, for example. Embodiments that do not include at least a portion of the user interface 240 can also be constructed. For example, the display device may be an external device connected to the ophthalmic imaging apparatus.

<motion>
The operation of the ophthalmologic photographing apparatus 1 will be described. It should be noted that preparatory processes similar to those in the related art, such as input of a patient ID, presentation of a fixation target, adjustment of a fixation position, alignment, focus adjustment, and OCT optical path length adjustment, have already been performed.

  An example of the operation of the ophthalmologic photographing apparatus 1 will be described with reference to FIG.

(S1: Apply a preparatory OCT scan to the fundus to obtain a preparatory image)
First, the ophthalmologic imaging apparatus 1 applies a preliminary OCT scan to the fundus oculi Ef using the optical scanner 44 and the OCT unit 100. The preliminary OCT scan is, for example, a wide-angle OCT scan. The image construction unit 220 constructs a preliminary image from data collected by the preliminary OCT scan. The preparatory image is sent to the parameter setting unit 231.

(S2: Set control parameters and create aberration map)
The parameter setting unit 231 sets a focus control parameter based on the preliminary image obtained in step S1. The set control parameters are stored in the storage unit 212, for example.

  In step S2 or a stage before that, the ophthalmologic imaging apparatus 1 may perform setting of a wide-angle OCT scan application area, setting of a center area, setting of a peripheral area, setting of scan control parameters, and the like. Any one of these conditions may be a fixed condition, a condition selected from a plurality of options, or a condition manually set by a user. The parameter setting unit 231 may set the focus control parameters based on the result of these settings and the preliminary image.

  In this example, it is assumed that the central area 310 and the peripheral area 320 shown in FIG. 5A, the spiral scan pattern 510 shown in FIG. 8A, and the focus control parameters shown in FIG. 9A are applied. It is also assumed that the outer edge of the peripheral area 320 defines the outer edge of the wide-angle OCT scan application area.

  Further, the aberration map creation unit 233 creates an aberration map of the eye E based on the preliminary image acquired in step S1. The created aberration map is stored in the storage unit 212.

(S3: Control the optical scanner based on the scan start position)
The scan control unit 213 specifies a scan start position based on the scan control parameters set in step S2 or earlier, and controls the optical scanner 44 based on the scan start position. Thereby, each galvanomirror included in the optical scanner 44 is arranged in a direction corresponding to the scan start position.

  In this example, typically, a fixation target corresponding to a fixation position for acquiring an image centered on the macula is displayed on the LCD 39, and the center of the wide-angle OCT scan application area is set to the center of the macula. You. Assuming that the alignment state and the fixation state of the eye E are favorable, the macula center is arranged on the optical axis of the measurement arm. Therefore, in this example, each galvanomirror of the optical scanner 44 is arranged at the neutral position.

(S4: Move OCT focusing lens based on initial focus position)
The focus control unit 214 specifies an initial focus position in the focus control based on the focus control parameters set in step S2, controls the OCT focus driving unit 43A based on the initial focus position, and controls the OCT focus lens 43. Move.

In the present example, it is identified as a focus position zeta ₁₁ an initial focus position corresponding to the scan start position n = 0 shown in Figure 9A, so as to place the OCT focusing lens 43 at a position corresponding to the initial focal position zeta ₁₁ The control of the OCT focus driving unit 43A is executed.

  Note that the control according to step S4 may be performed before the control according to step S3. Further, the control according to step S3 and the control according to step S4 may be performed in parallel.

(S5: Control the aberration correction device based on the initial aberration correction amount)
The aberration correction control unit 215 specifies an initial aberration correction amount in the aberration correction control based on the aberration map created in step S2. For example, the aberration correction control unit 215 can obtain an aberration correction amount corresponding to the scan start position (x, y) specified in step S3 from the aberration map.

  At this time, when any one of the plurality of scan positions defined in the aberration map matches the scan start position specified in step S3, the aberration correction control unit 215 determines, for example, the scan position corresponding to the scan start position. The aberration correction amount is set to the initial aberration correction amount.

  When none of the plurality of scan positions defined in the aberration map coincides with the scan start position specified in step S3, the aberration correction control unit 215 determines, for example, the plurality of scan positions defined in the aberration map. The scan position closest to the scan start position is specified, and the aberration correction amount at the specified scan position is set as the initial aberration correction amount.

  The aberration correction control unit 215 controls the aberration correction device 47 so that the specified initial aberration correction amount is applied.

(S6: instruction to start wide-angle OCT scan)
After the control in step S3, the control in step S4, and the control in step S5 are completed, an instruction to start a wide-angle OCT scan is input to the scan control unit 213, the focus control unit 214, and the aberration correction control unit 215. This instruction may be given manually by the user, or when a predetermined condition is satisfied (for example, the completion of the control of step S3, the control of step S4, and the control of step S5). The main control unit 211 may perform the processing automatically.

(S7: Cooperative execution of scan control, focus control, and aberration correction control is started)
Upon receiving the start instruction in step S6, the scan control unit 213, the focus control unit 214, and the aberration correction control unit 215 start control in cooperation with each other, so that the wide-angle OCT scan is started.

  In this example, the scan control by the scan control unit 213 and the focus control by the focus control unit 214 are executed based on the focus control parameters (the graph indicating the relationship between the scan position n and the focus position z) shown in FIG. 9A. . Further, in parallel with these controls, aberration correction control by the aberration correction control unit 215 is executed.

  Describing in more detail, the scan control unit 213 sequentially operates a plurality of scan points (scan positions n = 0 to N-1 shown in FIG. 9A) arranged along the spiral scan pattern 510 shown in FIG. 8A. The optical scanner 44 and the OCT unit 100 are controlled so that the A-scan is applied to.

  In parallel with this, when the A-scan is applied to each scan position n shown in FIG. 9A, the focus control unit 214 moves the focus position to a position corresponding to the focus position z = ζ (n) corresponding to this scan position n. The OCT focusing drive unit 43A is controlled so that the OCT focusing lens 43 is disposed.

  Further, in parallel with these, when the A-scan is applied to each scan position n shown in FIG. 9A, the aberration correction control unit 215 specifies a scan position in the aberration map corresponding to the scan position n, The aberration correction device 47 is controlled so that the aberration correction amount associated with the specified scan position is applied. Note that the aberration correction amount corresponding to each scan position n shown in FIG. 9A can be obtained before the start of the wide-angle OCT scan.

  By such parallel control, the fundus is moved according to the focus control parameters shown in FIG. 9A, and the amount of aberration correction is changed according to the aberration map, while the fundus is scanned according to the spiral scan pattern 510 shown in FIG. 8A. It is possible to scan Ef.

(S8: Start tracking)
In response to the start of the cooperative control in step S7, or at an arbitrary timing before the start of the cooperative control, the projection position of the measurement light LS (the application position of the A-scan) in accordance with the movement of the eye E to be inspected. The tracking for correcting () is started. The tracking is executed by the fundus camera unit 2, the movement detection unit 232, the scan control unit 213, and the like in the manner described above. Accordingly, even when the eye E moves during execution of the wide-angle OCT scan, the spiral scan pattern 510 illustrated in FIG. 8A can be applied.

(S9: Wide-angle OCT scan completed)
The wide-angle OCT scan started in step S7 ends when, for example, the OCT scan along the spiral scan pattern 510 shown in FIG. 8A is performed.

  Note that the OCT scan along the wide-angle OCT scan pattern is performed one or more predetermined times. For example, the OCT scan along the spiral scan pattern 510 can be performed two or more times. In this case, in the next step S9, two or more OCT images are constructed from two or more data sets collected by these two or more OCT scans, and the two or more OCT images are combined (averaged). be able to.

(S10: Construct OCT image according to wide-angle OCT scan pattern)
The image construction unit 220 constructs an OCT image from data collected by the wide-angle OCT scan performed in steps S7 to S9.

  The spiral scan pattern 510 shown in FIG. 8A is typically defined using a two-dimensional polar coordinate system (r, θ). Using a two-dimensional polar coordinate system (r, θ), the spiral scan pattern 510 is defined, for example, by the following equation: x = cos θ−θ × sin θ, y = sin θ + θ × cos θ.

  In this case, the OCT image constructed in step S10 is also defined using the two-dimensional polar coordinate system (r, θ). That is, the positions of the plurality of A-scan images constituting the OCT image constructed in step S10 are defined using the two-dimensional polar coordinate system (r, θ).

In this example, since the positions of the plurality of A-scans forming the spiral scan pattern 510 shown in FIG. 8A correspond to the plurality of scan positions n = 0 to N-1 shown in FIG. 9A, respectively, it is constructed in step S10. The positions of the plurality of A-scan images correspond to the plurality of scan positions n = 0 to N−1, respectively. For example, the step S10, OCT images _{H 1} shown in FIG. 12 is constructed. OCT images _{H 1} is composed of the scanning position n = _{n p} assigned A scanned image A _{(n p).} Note that each scan position n = _np is defined using a two-dimensional polar coordinate system (r, θ).

  The definition formula of the spiral scan pattern is not limited to this example, and the coordinate system defining the wide-angle OCT scan pattern and the OCT image is not limited to the two-dimensional polar coordinate system.

(S11: Coordinate transformation is applied to the OCT image)
The image construction unit 220 applies coordinate transformation to the OCT image constructed in step S10.

  For example, when a wide-angle OCT scan pattern including a curved scan pattern defined in a polar coordinate system having the origin at the center of the OCT scan application area is applied, the image constructing unit 220 determines the eye E to be inspected according to the curved scan pattern. An OCT image defined in a polar coordinate system is formed from the data collected by the OCT scan applied to (S10), and this OCT image is converted into an image defined in a three-dimensional orthogonal coordinate system (S11).

If in step S10 the OCT image _{H 1} shown in FIG. 12 is constructed, the image construction unit 220, a two-dimensional polar coordinate system (r, theta) and two-dimensional orthogonal coordinate system (x, y) coordinate conversion formula between the , The coordinates of each scan position n = _np defined in the two-dimensional polar coordinate system (r, θ) are converted into the coordinates defined in the two-dimensional orthogonal coordinate system (x, y). This coordinate conversion formula is, for example, the aforementioned (x = cos θ−θ × sin θ, y = sin θ + θ × cos θ).

By such coordinate conversion, for example, a group of OCT images H ₂ (m) (m = 1, 2,..., M) shown in FIG. 13 is obtained. Each OCT image H ₂ (m) is a B-scan image along the x direction, and is defined using a two-dimensional orthogonal coordinate system (x, z). Moreover, M pieces of OCT images _{H 2 (1) ~H 2 (} M) are arranged along the y-direction. Thus, M pieces of OCT images _{H 2 (1) ~H 2 (} M) is defined using three-dimensional orthogonal coordinate system (x, y, z).

(S12: construct a three-dimensional image from the coordinate-transformed OCT image)
The image construction unit 220 can construct a three-dimensional image from the OCT image after the coordinate transformation obtained in step S11.

In this example, in step S11, for example, M pieces of OCT images _H 2 is a stack data ₍₁₎ ~H 2 (M) is obtained. Image construction unit 220 is able to build a volume data voxel the M pieces of OCT images _{H 2 (1) ~H 2 (} M).

(S13: A rendered image of a three-dimensional image is displayed)
The image construction unit 220 can render the three-dimensional image constructed in step S12. The main control unit 211 can cause the display unit 241 to display the obtained rendering image.

<Action / Effect>
The operation and effect of the exemplary embodiment will be described.

  An ophthalmologic imaging apparatus (1) according to an exemplary embodiment includes a data collection unit, a storage unit, an aberration correction unit, and a control unit.

  The data collection unit scans the posterior segment of the subject's eye (E) with light to collect data. In the above example, the data collection unit includes the OCT unit 100 and elements (such as the retroreflector 41, the OCT focusing lens 43, the optical scanner 44, and the objective lens 22) in the fundus camera unit 2 that constitute a measurement arm. .

  Although the data collection unit in the above example has the OCT function, the data collection unit is not limited to this, and it is only necessary to be able to collect data of the posterior segment by optical scanning. For example, the data collection unit may have an SLO function.

  The storage unit stores in advance a map (aberration map) representing a distribution of the amount of aberration correction in a specific area that is at least a part of the scan area by the data collection unit. In the above example, the storage unit includes the storage unit 212.

  The aberration corrector corrects at least the aberration caused by the subject's eye (E). In the above example, the aberration correction unit includes the aberration correction device 47.

  The control unit cooperatively executes control of the data collection unit for scanning the region of the posterior segment corresponding to the specific area of the aberration map and control of the aberration correction unit based on the aberration map. In the above example, the control unit includes the main control unit 211, the scan control unit 213 controls the data collection unit, and the aberration correction control unit 215 controls the aberration correction unit.

  According to the present embodiment, since the scan is performed while performing the aberration correction according to the fundus shape using the aberration map obtained in advance, the aberration measurement is performed while performing the scan, and the aberration correction amount is also used. There is no need to perform calculations. On the other hand, in the related art, since aberration correction is performed by adaptive optics using active optics, it is necessary to perform aberration measurement and aberration correction amount calculation while scanning.

  It is considered that the shape of the fundus of the eye to be examined does not significantly change except in cases such as before and after the operation and long-term observation of the disease. Therefore, the aberration correction can be performed with sufficient accuracy and sufficient accuracy even by referring to the aberration map without performing the aberration measurement and the aberration correction amount calculation in parallel with the scanning as in the related art.

  Therefore, according to the present embodiment, high-speed processing can be performed over a wide range of the posterior segment without causing problems such as an increase in processing load, an increase in hardware and software complexity and cost, and a complicated operation and control. It is possible to obtain a high quality image by applying an optical scan.

  In the present embodiment, the aberration map may record an aberration correction amount corresponding to each of a plurality of positions in the specific area. In the above example, the aberration map 219 that defines the scan position in the two-dimensional coordinate system (scan coordinate system) corresponds to “plurality of positions” in this example.

  Further, the control unit controls the data collection unit to scan one of a plurality of positions in the specific area, and controls the aberration based on the aberration correction amount corresponding to the one position recorded in the aberration map. The control of the correction unit may be executed in parallel.

  In the present embodiment, the data collection unit may include an optical scanner that deflects light for scanning the posterior segment. In the above example, the optical scanner includes the optical scanner 44.

  Further, the aberration map may record an aberration correction amount corresponding to each of a plurality of pieces of control information for the optical scanner. In the above example, the parameter indicating the direction of the deflection mirror (galvano mirror) included in the optical scanner 44 is used for defining the scan position, or the parameter included in the signal for controlling the optical scanner 44 is defined as the scan position. Is equivalent to the “plurality of control information” in this example.

  Further, the control unit controls the optical scanner based on one of the plurality of pieces of control information and the aberration correction unit based on the aberration correction amount corresponding to the one control information recorded in the aberration map. It may be configured to execute in parallel.

  In the present embodiment, the specific area of the aberration map may include at least a peripheral area of the scan area.

  Generally, the peripheral area of the scan area corresponds to a position distant from the center of the fundus, and the peripheral area of the wide-angle scan area corresponds to the peripheral part of the fundus. Therefore, scanning of the peripheral area is relatively greatly affected by aberration. By setting the specific area of the aberration map so as to include the peripheral area of the scan area, it becomes possible to effectively correct aberrations that occur in scanning of the periphery of the fundus or the like where it is highly necessary to correct aberrations.

  In the present embodiment, the control unit controls the data collection unit according to a scan pattern including a continuous first partial pattern for the central region of the scan area different from the peripheral region and a continuous second partial pattern for the peripheral region. , May be configured to execute in cooperation with the control of the aberration correction unit based on the aberration map.

  According to this example, it is possible to apply a scan pattern including a continuous first partial pattern for the central region and a continuous second partial pattern for the peripheral region. As described above, the influence of the aberration is relatively small in the central portion of the fundus, and the effect is relatively large in the peripheral portion of the fundus. Therefore, by applying the scan pattern of the present example, control of the aberration correction unit becomes easy. More specifically, it is not necessary to change the aberration correction amount (largely) while the central region is continuously scanned, and the aberration correction amount is not changed while the peripheral region is continuously scanned. It is not necessary to change the aberration correction amount (significantly), and it is sufficient to change the aberration correction amount (significantly) only from the end of the scan of the central region to the start of the peripheral region. On the other hand, when the raster scan is applied as in the related art, since the aberration correction amount needs to be greatly changed between each B scan, the control of the aberration correction unit must be performed at an extremely high speed.

  In the present embodiment, the scan pattern may include a curved scan pattern defined in a polar coordinate system with the origin at the center of the scan area.

  In setting the curved scan pattern, for example, the structural characteristics and control characteristics of the optical scanner (44), a required scanning speed, a required scanning density, and the like can be considered.

  In the present embodiment, the curved scan pattern may be a spiral scan pattern (510) from the center of the scan area to the outer edge. Alternatively, the curved scan pattern may be a spiral scan pattern from the outer edge of the scan area to the center (520).

  Another example of a curved scan pattern is a concentric scan pattern.

  The ophthalmologic imaging apparatus (1) according to the present embodiment may include an image construction unit that constructs an image from data collected by the data collection unit. In the above example, the image construction unit includes the image construction unit 220.

The image builder can form an image (eg, an OCT image H ₁ ) defined in a polar coordinate system from data collected by a scan applied to the posterior segment according to a curved scan pattern. Further, the image construction unit can convert the image defined by the polar coordinate system (for example, the OCT image H ₁ ) into an image defined by the three-dimensional orthogonal coordinate system (for example, the OCT image H ₂ (m)). .

  According to such a configuration, it is possible to construct an image defined in a three-dimensional orthogonal coordinate system that can easily perform image processing and analysis from an image obtained using the curved scan pattern.

  The ophthalmologic photographing apparatus (1) according to the present embodiment includes a photographing unit that repeatedly photographs the eye to be examined (E), a movement detecting unit that analyzes a time-series image acquired by the photographing unit, and detects movement of the eye to be examined. May be further included. In this example, the imaging unit includes the fundus camera unit 2 and the movement detection unit includes the movement detection unit 232.

  In addition, the data collection unit may include an optical scanner that deflects light for scanning the posterior segment. In this example, the optical scanner includes an optical scanner 44.

  Further, the control unit may be configured to control the optical scanner based on an output from the movement detection unit while controlling the data collection unit and the aberration correction unit in cooperation. Here, the scan control unit 213 controls the data collection unit and the optical scanner, and the aberration correction control unit 215 controls the aberration correction unit.

  According to such a configuration, it is possible to perform a wide-angle scan while performing tracking for correcting the projection position of the scan light in accordance with the movement of the eye to be inspected. Thus, even if the subject's eye moves during the wide-angle scan, a scan corresponding to the wide-angle scan pattern can be suitably performed. In addition, it is possible to avoid the interruption and the redo of the scan.

  In the present embodiment, the storage unit may store in advance two or more maps corresponding to two or more diopter values. In this case, the control unit can select a map corresponding to the diopter value of the eye to be inspected from two or more maps, and execute control of the aberration control unit based on the selected map.

  According to such a configuration, it is possible to perform aberration correction at the time of scanning using an aberration map according to the diopter of the eye to be inspected, so that it is possible to further improve image quality.

  In the present embodiment, the data collection unit may include an OCT data collection unit that collects OCT data by applying the OCT scan to the posterior segment. In the above example, the OCT data collecting unit includes the OCT unit 100 and the elements (the retroreflector 41, the OCT focusing lens 43, the optical scanner 44, the objective lens 22, etc.) in the fundus camera unit 2 that constitute the measurement arm. Including.

  Further, the ophthalmologic imaging apparatus (1) according to the present embodiment may include an OCT image construction unit that constructs an OCT image from the OCT data collected by the OCT data collection unit. In the above example, the OCT image construction unit includes the image construction unit 220.

  Furthermore, the ophthalmologic imaging apparatus (1) according to the present embodiment may include a map creating unit that creates an aberration map stored in the storage unit based on the OCT image constructed by the OCT image constructing unit. In the above example, the map creator includes the aberration map creator 233.

  According to such a configuration, it is possible to perform aberration correction at the time of scanning (optical scanning such as OCT scanning and SLO scanning) using an individual aberration map corresponding to the eye to be inspected. It becomes possible to plan.

  An exemplary embodiment provides a method for controlling an ophthalmic imaging device. An ophthalmologic photographing apparatus to which this control method is applied includes a data collection unit that scans the posterior segment of the subject's eye with light to collect data, and an aberration correction unit that corrects at least aberration caused by the subject's eye.

  This control method includes a map preparation step and a control step. The map preparation step prepares a map representing the distribution of the amount of aberration correction in a specific area that is at least a part of the scan area by the data collection unit. In the control step, control of the data collection unit for scanning the region of the posterior segment corresponding to the specific area and control of the aberration correction unit based on the map are cooperatively executed.

  Any of the items described in the exemplary embodiments can be combined with such a method for controlling an ophthalmologic imaging apparatus.

  The exemplary embodiment provides a program that causes a computer to execute such a control method. This program can be combined with any of the items described in the exemplary embodiments.

  It is also possible to create a computer-readable non-transitory recording medium on which such a program is recorded. This recording medium can be combined with any of the items described in the exemplary embodiments. The non-transitory recording medium may be in any form, such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory.

  According to the method, the program, or the recording medium according to the exemplary embodiment, it is possible to increase the processing load, increase the complexity and cost of hardware and software, and increase the complexity of computation and control, thereby avoiding problems in the rear view. It is possible to apply a high-speed optical scan to a wide area of a part and obtain a high-quality image. In addition, an operation and an effect according to a matter combined with the method, the program, or the recording medium according to the exemplary embodiment are exerted.

  The configuration described above is only an example of the embodiment of the present invention. Therefore, arbitrary modifications (omission, substitution, addition, etc.) can be made within the scope of the present invention.

  For example, the aberration correction unit is not limited to an aberration correction device as an optical element, but may be a processor and a program that can correct aberration by calculation, for example. Compensated aberration correction is described, for example, in the following document: SA Hojjatoleslami, MRN Avanaki, and A. Gh. Podoleanu “Image quality improvement in optical coherence tomography using Lucy-Richardson deconvolution algorithm”, Applied Optics, Vol. 52 , Issue 23, pp.5663-5670 (2013).

  In this case, the following modified examples can be configured. That is, the ophthalmologic imaging apparatus according to the modification includes the data collection unit and the aberration correction unit. The data collection unit collects data by scanning the posterior segment of the subject's eye with light. The aberration correction unit includes a processor that operates according to a program, and corrects an image aberration based on data collected by the data collection unit. The image area to which the aberration corrector applies the aberration correction may be, for example, the same as a specific area in the aberration map.

  Also in this modification, a control method, a program, and a recording medium similar to those of the above-described exemplary embodiment can be configured. In addition, any of the items described in the exemplary embodiments can be combined with this modification.

1 Ophthalmic imaging apparatus 100 OCT unit 210 Control unit 211 Main control unit 212 Storage unit 213 Scan control unit 214 Focus control unit 215 Aberration correction control unit 219 Aberration map 220 Image construction unit 230 Data processing unit 231 Parameter setting unit 232 Movement detection unit 233 Aberration map creation unit 240 User interface 241 Display unit 242 Operation unit

Claims (14)

A data collection unit that scans the back eye of the subject's eye with light to collect data;
A storage unit that stores in advance a map representing a distribution of the amount of aberration correction in a specific area that is at least a part of a scan area by the data collection unit;
An aberration correction unit that corrects at least aberration caused by the subject's eye,
An ophthalmologic imaging apparatus, comprising: a control unit configured to control the data collection unit to scan a region of the posterior segment corresponding to the specific area, and to control the aberration correction unit based on the map. . In the map, an aberration correction amount corresponding to each of a plurality of positions in the specific area is recorded,
The control unit controls the data collection unit to scan one of the plurality of positions, and the aberration correction unit based on an aberration correction amount corresponding to the one position recorded in the map. The ophthalmologic imaging apparatus according to claim 1, wherein the control is performed in parallel. The data collection unit includes an optical scanner that deflects light for scanning the posterior segment,
In the map, an aberration correction amount corresponding to each of a plurality of pieces of control information for the optical scanner is recorded,
The control unit controls the optical scanner based on one control information of the plurality of control information, and controls the aberration correction unit based on an aberration correction amount corresponding to the one control information recorded on the map. The ophthalmologic imaging apparatus according to claim 1, wherein the control and the control are performed in parallel. The ophthalmologic imaging apparatus according to claim 1, wherein the specific area includes at least a peripheral area of the scan area. The control unit controls the data collection unit according to a scan pattern including a continuous first partial pattern for a central region of the scan area different from the peripheral region and a continuous second partial pattern for the peripheral region. 5. The ophthalmologic photographing apparatus according to claim 4, wherein the control is performed in cooperation with control of the aberration correction unit based on the map. The ophthalmologic photographing apparatus according to claim 5, wherein the scan pattern includes a curved scan pattern defined in a polar coordinate system having a center of the scan area as an origin. The curvilinear scan pattern is one of a spiral scan pattern from the center of the scan area to the outer edge and a spiral scan pattern from the outer edge of the scan area to the center. The ophthalmologic imaging apparatus according to the above. An image construction unit that constructs an image from data collected by the data collection unit,
The image constructing unit forms an image defined in the polar coordinate system from data collected by a scan applied to the posterior segment according to the curved scan pattern, and the image defined in the polar coordinate system. The ophthalmologic imaging apparatus according to claim 6, wherein the image is converted into an image defined by a three-dimensional orthogonal coordinate system. A photographing unit for repeatedly photographing the subject's eye,
Further comprising a movement detection unit that analyzes the time-series image acquired by the imaging unit and detects the movement of the subject's eye,
The data collection unit includes an optical scanner that deflects light for scanning the posterior segment,
The said control part controls the said optical scanner based on the output from the said movement detection part, controlling the said data collection part and the said aberration correction part cooperatively. The any one of Claims 1-8 characterized by the above-mentioned. An ophthalmologic photographing apparatus according to any of the claims. The storage unit stores in advance two or more maps corresponding to two or more diopter values,
The control unit selects a map corresponding to the diopter value of the subject's eye from the two or more maps, and executes control of the aberration control unit based on the selected map. Item 10. The ophthalmologic imaging apparatus according to any one of Items 1 to 9. The data collection unit includes an OCT data collection unit that collects OCT data by applying an optical coherence tomography (OCT) scan to the posterior segment.
An OCT image construction unit configured to construct an OCT image from the OCT data collected by the OCT data collection unit;
10. A map creating unit that creates a map stored in the storage unit based on the OCT image constructed by the OCT image constructing unit. The method according to claim 1, further comprising: Ophthalmic photography equipment. A method for controlling an ophthalmologic imaging apparatus including a data collection unit that scans the rear eye of the subject's eye with light to collect data and an aberration correction unit that corrects at least aberration caused by the subject's eye,
Preparing a map representing a distribution of aberration correction amounts in a specific area that is at least a part of the scan area by the data collection unit,
A control step of coordinating control of the data collection unit for scanning an area of the posterior segment corresponding to the specific area, and control of the aberration correction unit based on the map. How to control the device.   A program for causing a computer to execute the method for controlling an ophthalmologic imaging apparatus according to claim 12. A non-transitory computer-readable recording medium on which the program according to claim 13 is recorded.

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