JP2019130046A - Ophthalmologic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an improvement of a transillumination method for suitably grasping an opaque portion in an eye to be inspected. An embodiment is an ophthalmic apparatus for optically acquiring data of an eye to be inspected, and includes a projection system, an anterior ocular segment photographing system, and an image processing unit. The projection system projects illumination light for transillumination photography onto the fundus of the eye to be inspected. The anterior segment imaging system photographs the anterior segment of the eye to be inspected from which the illumination light is projected onto the fundus from two or more directions. The image processing unit analyzes two or more anterior eye image images corresponding to two or more directions acquired by the anterior eye photography system, and identifies an opaque region corresponding to the opacity inside the eye to be inspected. [Selection diagram] FIG. 3B

Description

  The present invention relates to an ophthalmic apparatus.

  In the field of ophthalmology, a device for obtaining an image of an eye to be examined (ophthalmologic photographing device) and a device for measuring characteristics of the eye to be examined (ophthalmic measuring device) are used for medical care.

  Examples of ophthalmic imaging devices include an optical coherence tomography (Optical Coherence Tomography, OCT) for obtaining data using an optical coherence tomography, a fundus camera for photographing the fundus, and a fundus image obtained by laser scanning using a confocal optical system. There is a scanning laser opthalmoscope (SLO).

  Examples of the ophthalmologic measurement apparatus include an eye refraction inspection apparatus (refractometer) that measures the refractive characteristics of the eye to be examined, a wave front analyzer that obtains aberration data of the eye to be examined using a Hartmann-Shack sensor, and the like.

  The ophthalmologic apparatus exemplified above projects light toward the fundus of the eye to be examined, and obtains data based on the return light. Therefore, for example, when an intermediate translucent body (a crystalline lens, a vitreous body, etc.) is turbid like a cataract eye, the projection light and the return light are affected by this, and photographing and measurement may not be performed appropriately.

  The transillumination method is known as a method for grasping the turbidity of the intermediate translucent material. The transillumination method is a method in which illumination light is projected onto the fundus and the pupil region illuminated from inside the eye to be examined is reflected. In the transillumination image obtained by this, the cloudy part is projected as a shadow. When an error occurs in imaging or measurement, the alignment, that is, the incident position of light with respect to the eye to be inspected is adjusted so as to avoid the turbid portion with reference to the illumination image.

  In general, in the transillumination method, it is desirable to ensure fundus reflection with a sufficient amount of light to obtain a high-quality transillumination image. On the other hand, considering the safety of the eye to be examined, the amount of light incident on the eye to be examined is limited. In order to satisfy both of these two conditions, it is required to ensure the brightness of fundus reflection by efficiently using the amount of illumination light.

  In order to satisfy this requirement, it is conceivable to make illumination light enter through the apex of the cornea. When this method is applied and the conventional transillumination method is performed, the corneal reflection image (bright spot) of the illumination light is mixed into the transillumination image, so check whether there is turbidity at the position of the corneal reflection image. The problem that cannot be done.

Japanese Patent No. 4469205 Japanese Patent No. 4733511 Japanese Patent No. 5500587 Japanese Patent No. 6143447

  An object of the present invention is to provide an improvement of the transillumination method for appropriately grasping the cloudy portion in the eye to be examined.

  A first aspect of an embodiment is an ophthalmologic apparatus for optically acquiring data of an eye to be examined, the projection system for projecting illumination light for transillumination photographing on the fundus of the eye to be examined, and the illumination An anterior segment imaging system that images the anterior segment of the subject's eye in which light is projected onto the fundus from two or more directions, and 2 corresponding to the two or more directions acquired by the anterior segment imaging system. And an image processing unit that analyzes the above anterior segment image and identifies a turbid region corresponding to the turbidity inside the eye to be examined.

  A second aspect of the embodiment is the ophthalmologic apparatus according to the first aspect, wherein the image processing unit analyzes the two or more anterior ocular segment images and removes a corneal reflection image caused by the illumination light. A composite image based on the two or more anterior segment images is formed.

  A third aspect of the embodiment is the ophthalmologic apparatus according to the second aspect, in which the image processing unit analyzes the two or more anterior eye images, and each of the two or more anterior eye images. An image that forms the composite image based on the reflected image removing unit that removes the corneal reflection image caused by the illumination light and the two or more anterior segment images from which the corneal reflection image has been removed by the reflected image removing unit. A synthesis unit.

  A fourth aspect of the embodiment is the ophthalmologic apparatus according to the third aspect, wherein the image processing unit forms a front image of the anterior eye part as the composite image.

  A fifth aspect of the embodiment is the ophthalmologic apparatus according to any one of the second to fourth aspects, wherein the data acquisition optical system for optically acquiring the data and the data acquisition optical system are moved. A drive control unit that controls the drive unit; and the image processing unit includes a first movement target determination unit that determines a movement target of the data acquisition optical system based on the composite image. The drive control unit controls the drive unit based on the movement target.

  A sixth aspect of the embodiment is the ophthalmologic apparatus according to any one of the second to fifth aspects, and further includes a display control unit that displays the composite image on a display unit.

  A seventh aspect of the embodiment is the ophthalmic apparatus according to any one of the second to fourth aspects, wherein the data acquisition optical system for optically acquiring the data and the data acquisition optical system are moved. A drive unit, a display control unit for displaying the composite image on a display unit, an operation unit for performing an alignment operation of the data acquisition optical system, and a drive for controlling the drive unit based on a signal from the operation unit And a control unit.

  An eighth aspect of the embodiment is the ophthalmologic apparatus according to the seventh aspect, wherein the image processing unit includes a first movement target determination unit that determines a movement target of the data acquisition optical system based on the composite image. And the display control unit causes the display means to display information for the alignment operation based on the movement target.

  A ninth aspect of the embodiment is the ophthalmic apparatus according to the first aspect, wherein the data acquisition optical system for optically acquiring the data, a drive unit that moves the data acquisition optical system, and the drive A drive control unit that controls the image processing unit, wherein the image processing unit analyzes the two or more anterior segment images corresponding to the two or more directions acquired by the anterior segment imaging system, and A position information acquisition unit that acquires position information of the optometry, wherein the drive control unit applies alignment control based on the position information to the drive unit, and after the alignment control, the projection system transmits the illumination light. Project onto the fundus.

  A tenth aspect of the embodiment is the ophthalmologic apparatus according to the first aspect, wherein the data acquisition optical system for optically acquiring the data, a drive unit that moves the data acquisition optical system, and the drive A drive control unit that controls the image processing unit, the image processing unit includes a second movement target determination unit that determines a movement target of the data acquisition optical system based on the turbidity region, and the drive control unit includes: The drive unit is controlled based on the movement target.

  An eleventh aspect of the embodiment is the ophthalmologic apparatus according to the first aspect, in which the image processing unit analyzes the two or more anterior eye images, and among the two or more anterior eye images. A cornea reflection image caused by the illumination light is removed from at least one anterior segment image.

  A twelfth aspect of the embodiment is the ophthalmic apparatus according to any one of the first to eleventh aspects, wherein the projection system projects light for acquiring the data onto the fundus as the illumination light.

  A thirteenth aspect of the embodiment is the ophthalmic apparatus according to the twelfth aspect, further including an optical scanner for acquiring the data by optical scanning, and the projection system is configured to transmit the data via the optical scanner. Illumination light is projected onto the fundus.

  A fourteenth aspect of the embodiment is the ophthalmologic apparatus according to the thirteenth aspect, in which the measurement light is projected onto the fundus via the optical scanner, and the return light of the measurement light is overlapped with the reference light to cause interference light. And an OCT unit that generates the data based on the detection result of the interference light, and the projection system projects the measurement light onto the fundus as the illumination light.

  A fifteenth aspect of the embodiment is the ophthalmic apparatus according to the thirteenth or fourteenth aspect, wherein the optical scanner changes the deflection direction of the illumination light with time.

  A sixteenth aspect of the embodiment is an ophthalmologic apparatus for optically acquiring data of an eye to be examined, the projection system for projecting illumination light for transillumination photographing on the fundus of the eye to be examined, and the illumination An anterior segment imaging system that images the anterior segment of the subject's eye in which light is projected onto the fundus from two or more directions, and 2 corresponding to the two or more directions acquired by the anterior segment imaging system. And an image processing unit that analyzes the above anterior segment image and forms a composite image based on the two or more anterior segment images from which the corneal reflection image caused by the illumination light has been removed.

  According to the present invention, it is possible to appropriately grasp the cloudy portion in the eye to be examined by improving the transillumination method.

It is a schematic diagram showing an example of composition of an ophthalmology device concerning an embodiment. It is a schematic diagram showing an example of composition of an ophthalmology device concerning an embodiment. It is a schematic diagram showing an example of composition of an ophthalmology device concerning an embodiment. It is a schematic diagram showing an example of composition of an ophthalmology device concerning an embodiment. It is a schematic diagram showing an example of composition of an ophthalmology device concerning an embodiment. It is a schematic diagram showing an example of composition of an ophthalmology device concerning an embodiment. It is a schematic diagram showing an example of composition of an ophthalmology device concerning an embodiment. It is a schematic diagram showing an example of composition of an ophthalmology device concerning an embodiment. It is a flowchart showing an example of the operation | movement which the ophthalmologic apparatus which concerns on embodiment can perform. It is a flowchart showing an example of the operation | movement which the ophthalmologic apparatus which concerns on embodiment can perform.

  Exemplary aspects of the ophthalmologic apparatus according to the embodiment will be described in detail with reference to the drawings. The ophthalmologic apparatus according to the embodiment is used to optically acquire data of an eye to be examined (that is, using light and using optical technology). In particular, the ophthalmologic apparatus according to the embodiment can acquire the data of the eye to be examined by making light enter the eye through the pupil of the eye to be examined.

  Such an ophthalmologic apparatus includes, for example, at least one of an imaging function and a measurement function. Examples of an ophthalmologic apparatus having an imaging function include an optical coherence tomometer, a fundus camera, and a scanning laser ophthalmoscope. Examples of an ophthalmologic apparatus having a measurement function include an eye refraction inspection apparatus, a wavefront analyzer, a microperimeter, and a perimeter.

  In the following illustration, an ophthalmologic photographing apparatus combining a swept source OCT and a fundus camera will be described, but the embodiment is not limited to this. The type of OCT is not limited to swept source OCT, and may be, for example, spectral domain OCT.

  The swept source OCT divides light from a wavelength tunable light source (wavelength swept light source) into measurement light and reference light, and superimposes return light of the measurement light from the test object on the reference light to generate interference light. In this technique, the interference light is detected by a balanced photodiode or the like, and an image is formed by applying Fourier transform or the like to detection data collected in response to wavelength sweeping and measurement light scanning.

  Spectral domain OCT splits light from a low-coherence light source into measurement light and reference light, and superimposes return light of the measurement light from the test object on the reference light to generate interference light. The spectrum of this interference light This is a technique in which a distribution is detected by a spectroscope and an image is formed by applying Fourier transform or the like to the detected spectral distribution.

  Thus, the swept source OCT is an OCT technique for acquiring a spectrum distribution by time division, and the spectral domain OCT is an OCT technique for acquiring a spectrum distribution by space division. Note that the OCT technique that can be used in the embodiment is not limited thereto, and an embodiment using any OCT technique (for example, time domain OCT) different from these may be employed.

  In the present specification, unless otherwise specified, “image data” and “image” based thereon are not distinguished. Further, unless otherwise specified, the region or tissue of the eye to be examined and the image representing it are not distinguished.

<Constitution>
The exemplary ophthalmologic apparatus 1 shown in FIG. 1 includes a fundus camera unit 2, an OCT unit 100, and an arithmetic control unit 200. The retinal camera unit 2 is provided with an optical system and mechanism for acquiring a front image of the eye E and an optical system and mechanism for performing OCT. The OCT unit 100 is provided with an optical system and a mechanism for performing OCT. The arithmetic control unit 200 includes one or more processors configured to execute various processes (calculation, control, etc.). Furthermore, the ophthalmologic apparatus 1 includes two anterior eye cameras 300 for photographing the anterior eye part from two directions.

  The retinal camera unit 2 is provided with a chin rest and a forehead support for supporting the subject's face. The chin rest and the forehead support correspond to the support portion 440 shown in FIGS. 4A and 4B. The base 410 stores a drive system such as the optical system drive unit 2A and an arithmetic control circuit. An optical system is stored in a housing 420 provided on the base 410. The objective lens 22 is housed in a lens housing portion 430 provided so as to protrude from the front surface of the housing 420.

  Furthermore, the ophthalmologic apparatus 1 may include an arbitrary element or an arbitrary unit such as a lens unit (for example, an anterior ocular segment OCT attachment) for switching a site to which OCT is applied.

  In this specification, the “processor” is, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), or a programmable logic device (eg, SPLD (Simple ProLigL). It means a circuit such as Programmable Logic Device (FPGA) or Field Programmable Gate Array (FPGA). For example, the processor implements the functions according to the embodiment by reading and executing a program stored in a storage circuit or a storage device.

<Fundus camera unit 2>
The fundus camera unit 2 is provided with an optical system for photographing the fundus oculi Ef of the eye E to be examined. The acquired digital image of the fundus oculi Ef (referred to as a fundus image, fundus photograph, etc.) is generally a front image such as an observation image or a captured image. The observation image is obtained by moving image shooting using near infrared light. The captured image is a still image using flash light in the visible region.

  The fundus 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 photographing optical system 30 detects the return light of the illumination light irradiated on the eye E. Measurement light from the OCT unit 100 is guided to the eye E through an optical path in the fundus camera unit 2. The return light of the measurement light projected on the eye E (for example, the fundus oculi Ef) is guided to the OCT unit 100 through the same optical path in the fundus camera unit 2.

  The 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 condensing lens 13, passes through the visible cut filter 14, and becomes near infrared light. Further, the observation illumination light is once converged in the vicinity of the photographing light source 15, reflected by the mirror 16, and passed through the relay lens system 17, the relay lens 18, the stop 19, and the relay lens system 20 to the aperture mirror 21. Led. The observation illumination light is reflected by the peripheral part of the perforated mirror 21 (region around the hole part), passes through the dichroic mirror 46, and is refracted by the objective lens 22 to illuminate the eye E (fundus Ef). To do. The return light of the observation illumination light from the 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 the mirror 32 via the photographing focusing lens 31. Further, the return light passes through the half mirror 33A, is reflected by the dichroic mirror 33, and forms an image 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. Note that the focus of the photographing optical system 30 is adjusted to match the fundus oculi Ef or the anterior eye segment.

  The light (imaging illumination light) output from the imaging 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 33 </ b> A, reflected by the mirror 32, passes through the hole of the perforated mirror 21 through the photographing focusing lens 31 and the dichroic mirror 55. The light beam that has passed through the aperture of the aperture mirror 21 passes through the dichroic mirror 46, is refracted by the objective lens 22, and is projected onto the fundus oculi Ef. The fixation target is typically used for guidance and fixation of the line of sight. The direction in which the line of sight of the eye E is guided (and fixed), that is, the direction in which fixation of the eye E is promoted is called a fixation position.

  The fixation position can be changed by changing the display position of the fixation target image on the screen of the LCD 39. Examples of fixation positions include a fixation position for acquiring an image centered on the macula, a fixation position for acquiring an image centered on the optic nerve head, and a position between the macula and the optic nerve head ( There are a fixation position for acquiring an image centered on the fundus center and a fixation position for acquiring an image of a part (a fundus peripheral portion) far away from the macula.

  A graphical user interface (GUI) or the like for designating at least one of such typical fixation positions can be provided. Further, a GUI or the like for manually moving the fixation position (display position of the fixation target) can be provided. It is also possible to apply a configuration in which the fixation position is automatically set.

  The configuration for presenting a 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 device (fixation matrix) in which a plurality of light emitting units (light emitting diodes or the like) are arranged in a matrix can be used instead of the display device. In this case, the fixation position of the eye E by the fixation target can be changed by selectively turning on the plurality of light emitting units. As another example, a fixation target capable of changing the fixation position can be generated by a device including one or more movable light emitting units.

  The alignment optical system 50 generates an alignment index used for alignment of the optical system with respect to the eye E. The alignment light output from the light emitting diode (LED) 51 passes through the diaphragm 52, the diaphragm 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 passes through and is projected onto the eye E through the objective lens 22. Return light (corneal reflection 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 auto-alignment can be executed based on the received light image (alignment index image).

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

  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 the intensity hyperopia. The diopter correction lens 71 is a minus lens (concave lens) for correcting intensity 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 photographing. In the measurement arm, a collimator lens unit 40, a retroreflector 41, a dispersion compensation member 42, an OCT focusing lens 43, an optical scanner 44, and a relay lens 45 are provided in this order from the OCT unit 100 side.

  The retro-reflector 41 is movable along the optical path of the measurement light LS incident thereon, thereby changing the length of the measurement arm. The change of the measurement arm length is used, for example, for optical path length correction according to the axial length, adjustment of the interference state, or the like.

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

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

  The optical scanner 44 is substantially disposed 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, for example, a galvano scanner capable of two-dimensional scanning. Typically, the optical scanner 44 includes a one-dimensional scanner (x-scanner) for deflecting measurement light in the ± x direction and a one-dimensional scanner (y-scanner) for deflecting measurement light in the ± y direction. Including. In this case, for example, either one of these one-dimensional scanners is arranged at a position optically conjugate with the pupil, or a position optically conjugate with the pupil is arranged between these one-dimensional scanners.

<OCT unit 100>
The exemplary OCT unit 100 shown in FIG. 2 is provided with an optical system for performing swept source OCT. This optical system includes an interference optical system. This interference optical system divides the light from the wavelength tunable light source into measurement light and reference light, and superimposes the return light of the measurement light projected on the eye E and the reference light passing through the reference light path to interfere light. And the interference light is detected. Data (detection signal) obtained by detecting the interference light is a signal representing the spectrum of the interference light and is sent to the arithmetic control unit 200.

  The light source unit 101 includes, for example, a near-infrared wavelength 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 the polarization controller 103 by the 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 is divided 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 generated by the fiber coupler 105 is guided to the collimator 111 by the optical fiber 110 and converted into a parallel light beam, and is guided to the retro-reflector 114 via the optical path length correction member 112 and the dispersion compensation member 113. The optical path length correction member 112 acts to match the optical path length of the reference light LR and the optical path length of the measurement light LS. The dispersion compensation member 113, together with the dispersion compensation member 42 disposed on the measurement arm, acts 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, thereby changing the length of the reference arm. The change of the reference arm length is used, for example, for optical path length correction corresponding to the axial length, adjustment of the interference state, or the like.

  The reference light LR that has passed through the retroreflector 114 passes through the dispersion compensation member 113 and the optical path length correction member 112, is converted from a parallel light beam to a focused light beam by the collimator 116, and enters the optical fiber 117. The reference light LR incident on the optical fiber 117 is guided to the polarization controller 118 and its polarization state is adjusted. The reference light LR is guided to the attenuator 120 through the optical fiber 119 and the amount of light is adjusted. Led.

  On the other hand, the measurement light LS generated by the fiber coupler 105 is guided to the collimator lens unit 40 through the optical fiber 127 and converted into a parallel light beam, and the retroreflector 41, the dispersion compensation member 42, the OCT focusing lens 43, and the optical scanner 44. , And through the relay lens 45, reflected by the dichroic mirror 46, refracted by the objective lens 22, and projected onto the eye E. 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 eye E travels in the reverse direction in the measurement arm, 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 incident through the optical fiber 128 and the reference light LR incident through the optical fiber 121. The fiber coupler 122 generates a pair of interference light LC by branching the generated interference light at a predetermined branching ratio (for example, 1: 1). The pair of interference lights LC are guided to the detector 125 through optical fibers 123 and 124, respectively.

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

  A clock KC is supplied from the light source unit 101 to the data collection system 130. The clock KC is generated in synchronization with the output timing of each wavelength that is swept within a predetermined wavelength range by the wavelength variable light source in the light source unit 101. For example, the light source unit 101 divides the light L0 of each output wavelength to generate two branched lights, optically delays one of the branched lights, synthesizes the branched lights, and combines the obtained synthesized lights. A clock KC is generated based on the detection signal. The data collection system 130 performs sampling of the detection signal (difference signal) input from the detector 125 based on the clock KC. The data collection system 130 sends the data obtained by 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 of these elements may be provided. In addition, elements for changing the difference (optical path length difference) between the measurement arm length and the reference arm length are not limited to these, and any element (such as an optical member or a mechanism) can be employed. .

<Calculation control unit 200>
The arithmetic control unit 200 controls each part of the ophthalmologic apparatus 1. The arithmetic control unit 200 executes various arithmetic processes. For example, the arithmetic control unit 200 performs signal processing such as Fourier transform on the spectrum distribution based on the sampling data group obtained by the data acquisition system 130 for each series of wavelength scans (for each A line), thereby performing each A A reflection intensity profile at the line is formed. Furthermore, the arithmetic control unit 200 forms image data by imaging the reflection intensity profile of each A line. The arithmetic processing for that is the same as the conventional swept source OCT.

  The arithmetic control unit 200 includes, for example, a processor, a RAM (Random Access Memory), a ROM (Read Only Memory), a hard disk drive, a communication interface, and the like. Various computer programs are stored in a storage device such as a hard disk drive. The arithmetic control unit 200 may include an operation device, an input device, a display device, and the like.

<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 such as a touch panel in which a display function and an operation function are integrated. 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 ophthalmologic photographing apparatus.

<Anterior Eye Camera 300>
The anterior segment camera 300 images the anterior segment of the eye E from two or more different directions. The anterior eye camera 300 includes an image sensor such as a CCD image sensor or a CMOS image sensor. In this embodiment, two anterior eye cameras 300 are provided on the surface of the fundus camera unit 2 on the subject side (see anterior eye cameras 300A and 300B shown in FIG. 4A). As shown in FIGS. 1 and 4A, the anterior eye cameras 300 </ b> A and 300 </ b> B are provided at positions deviating from the optical path passing through the objective lens 22. Hereinafter, one or both of the anterior eye cameras 300A and 300B may be denoted by reference numeral 300.

  In this embodiment, two anterior eye cameras 300A and 300B are provided, but typically, the number of anterior eye cameras may be an arbitrary number of two or more. In consideration of the arithmetic processing described later, a configuration that can shoot the anterior segment from two different directions is sufficient (but is not limited to this). One or more movable anterior segment cameras 300 may be provided.

  In this embodiment, the anterior segment camera 300 is provided separately from the illumination optical system 10 and the imaging optical system 30, but anterior segment imaging can be performed using at least the imaging optical system 30. That is, one of the two or more anterior segment cameras may include the photographing optical system 30. The anterior segment camera 300 according to this embodiment is only required to be able to photograph the anterior segment from two different (or more) directions.

  A configuration for illuminating the anterior segment may be provided. The anterior segment illumination means includes, for example, one or more light sources. Typically, at least one light source (eg, an infrared light source) can be provided in the vicinity of each of the two or more anterior segment cameras.

  Two or more anterior segment cameras can photograph the anterior segment substantially simultaneously from two or more different directions. “Substantially simultaneous” means that, in addition to the case where the photographing timings of two or more anterior eye cameras are simultaneous, for example, the case where there is a photographing timing deviation that can ignore the eye movement is allowed. Show. Thereby, an image when the eye E is in substantially the same position and orientation can be acquired by two or more anterior eye cameras.

  Shooting with two or more anterior segment cameras may be moving image shooting or still image shooting. In the case of moving image shooting, substantially simultaneous anterior ocular shooting as described above can be realized by controlling the shooting start timing to match or controlling the frame rate and shooting timing of each frame. . On the other hand, in the case of still image shooting, this can be realized by controlling to match the shooting timing.

<Control system>
An example of the configuration of the control system (processing system) of the ophthalmologic apparatus 1 is shown in FIGS. 3A and 3B. The control unit 210, the image forming unit 220, and the data processing unit 230 are provided in the arithmetic control unit 200, for example.

<Control unit 210>
The control unit 210 includes a processor and controls each unit of the ophthalmologic apparatus 1. The control unit 210 includes a main control unit 211 and a storage unit 212.

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

  The imaging focusing lens 31 arranged in the imaging optical path and the focus optical system 60 arranged in the illumination optical path are moved by an imaging focusing drive unit (not shown) under the control of the main control unit 211. The retro-reflector 41 provided in the measurement arm is moved by the retro-reflector (RR) drive unit 41A under the control of the main control unit 211. The OCT focusing lens 43 arranged on the measurement arm is moved by the OCT focusing driving unit 43A under the control of the main control unit 211. The optical scanner 44 provided in the measurement arm operates under the control of the main control unit 211. The retro-reflector 114 arranged on the reference arm is moved by the retro-reflector (RR) driving unit 114A under the control of the main control unit 211. Each of these drive units includes an actuator such as a pulse motor that operates under the control of the main control unit 211.

  For example, the moving mechanism 150 moves at least the fundus camera unit 2 in a three-dimensional manner. In a typical example, the moving mechanism 150 includes an x stage that can move in the ± x direction (left and right direction), an x moving mechanism that moves the x stage, and a y stage that can move in the ± y direction (up and down direction). , A y moving mechanism for moving the y stage, a z stage movable in the ± z direction (depth direction), and a z moving mechanism for moving 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. Examples of the data stored in the storage unit 212 include image data of an OCT image, image data of a fundus image, and eye information to be examined. The eye information includes subject information such as patient ID and name, left / right eye identification information, electronic medical record information, and the like.

  In the storage unit 212, aberration information (not shown) is stored in advance. In the aberration information, information on distortion aberration generated in the captured image due to the influence of the optical system mounted on each anterior segment camera 300 is recorded. Here, the optical system mounted on the anterior segment camera 300 includes an optical element that generates distortion, such as a lens. The aberration information can be said to be a parameter obtained by quantifying the distortion that these optical elements give to the photographed image.

  An example of a method for generating aberration information will be described. Taking the instrumental difference (difference in distortion) of the anterior segment camera 300 into consideration, the following measurement is performed for each anterior segment camera 300. The operator prepares a predetermined reference point. The reference point is an imaging target used for detecting distortion. The operator performs multiple shootings while changing the relative position between the reference point and the anterior eye camera 300. Thereby, a plurality of captured images of the reference point captured from different directions are obtained. The operator generates aberration information of the anterior eye camera 300 by analyzing a plurality of acquired captured images with a computer. The computer that performs the analysis processing may be the data processing unit 230 or any other computer (such as an inspection computer or a maintenance computer before product shipment).

The analysis process for generating aberration information includes, for example, the following steps:
An extraction step of extracting an image region corresponding to the reference point from each captured image;
A distribution state calculation step of calculating a distribution state (coordinates) of an image area corresponding to a reference point in each captured image;
A distortion aberration calculating step of calculating a parameter representing distortion based on the obtained distribution state;
A correction coefficient calculation step of calculating a coefficient for correcting distortion based on the obtained parameter.

  Parameters relating to distortion aberration given to an image by the optical system include principal point distance, principal point position (vertical direction, horizontal direction), lens distortion (radiation direction, tangential direction), and the like. The aberration information is configured as information (for example, table information) in which the identification information of each anterior eye camera 300 is associated with the correction coefficient corresponding thereto. The aberration information generated in this way is stored in the storage unit 212 by the main control unit 211. Such generation of aberration information and aberration correction based on the aberration information are referred to as camera calibration.

<Image forming unit 220>
The image forming unit 220 forms OCT image data based on the data collected by the data collection system 130. The image forming unit 220 includes a processor. The image forming unit 220 is realized by cooperation of hardware including a circuit and image forming software.

  The image forming unit 220 forms cross-sectional image data based on the data collected by the data collection system 130. This processing includes signal processing such as noise removal (noise reduction), filter processing, and fast Fourier transform (FFT) as in the case of the conventional swept source OCT.

  The image data formed by the image forming unit 220 is a group of images formed by imaging reflection intensity profiles in a plurality of A lines (scan lines along the z direction) arranged in an area to which an OCT scan is applied. A data set including image data (a group of A-scan image data).

  The image data formed by the image forming unit 220 is, for example, one or more B-scan image data or stack data formed by embedding a plurality of B-scan image data in a single three-dimensional coordinate system. The image forming unit 220 can also construct volume data (voxel data) by performing voxelization processing on the stack data. Stack data and volume data are typical examples of 3D image data expressed by a 3D coordinate system.

  The image forming unit 220 can process the three-dimensional image data. For example, the image forming unit 220 can construct new image data by applying rendering to the three-dimensional image data. Rendering techniques include volume rendering, maximum value projection (MIP), minimum value projection (MinIP), surface rendering, multi-section reconstruction (MPR), and the like. Further, the image forming unit 220 can construct projection data by projecting three-dimensional image data in the z direction (A-line direction, depth direction). Further, the image forming unit 220 can construct a shadowgram by projecting a part of the three-dimensional image data in the z direction. Note that a part of the three-dimensional image data projected to construct a shadowgram is set using segmentation, for example.

<Data processing unit 230>
The data processing unit 230 executes various data processing. For example, the data processing unit 230 can apply image processing and analysis processing to OCT image data, and can apply image processing and analysis processing to observation image data or captured image data. The data processing unit 230 includes, for example, at least one of a processor and a dedicated circuit board.

  The data acquisition system 250 shown in FIG. 3B is configured to optically acquire data of the eye to be examined. The data acquisition system 250 of this example is configured to acquire image data by applying OCT to the eye E to be examined. The data acquisition system 250 of this example includes an element group constituting a measurement arm provided in the fundus camera unit 2, an element group provided in the OCT unit 100, and an image forming unit 220. In another example, the data acquisition system 250 may include a configuration for acquiring a fundus image (the illumination optical system 10, the imaging optical system 30, etc.).

  The projection system 260 shown in FIG. 3B is configured to project illumination light for transillumination shooting onto the fundus oculi Ef. The projection system 260 may be configured to project light for the data acquisition system 250 to acquire data onto the fundus oculi Ef as illumination light for transillumination photography.

  When the data acquisition system 250 includes an optical scanner 44 for acquiring data by optical scanning, the projection system 260 projects illumination light for transillumination onto the fundus oculi Ef via the optical scanner 44. May be configured. As modalities for performing such optical scanning, there are OCT and SLO.

  In this example, OCT is applied, and the projection system 260 is configured to project the measurement light LS onto the fundus oculi Ef as illumination light for transillumination photography. When the measurement light LS in the swept source OCT is used as illumination light for transillumination as in this example, it is not necessary to perform wavelength sweeping. For example, the center wavelength of the variable wavelength light source included in the light source unit 101 can be used as illumination light for transillumination photography. In addition, the measurement light LS including a wavelength band with high sensitivity of the anterior segment imaging system 270 (anterior segment camera 300) can be used as illumination light for transillumination imaging. On the other hand, when the spectral domain OCT is applied, the measurement light that is low coherence light (broadband light) can be used as illumination light for continuous illumination photography, or a predetermined wavelength included in this measurement light can be selected. It can be extracted by an element (for example, a band pass filter) and used as illumination light for transillumination photography. The OCT measurement light is advantageous for illumination for transillumination photography in that high intensity light can be projected.

  When the data acquisition system 250 is configured to acquire data by optical scanning, the optical scanner 44 can temporally change the deflection direction of illumination light for transillumination imaging. The control of the optical scanner 44 is executed by the control unit 210. As a result, like the invention disclosed in Patent Document 3, it is possible to suppress speckle noise generated in the transillumination image.

  The anterior ocular segment imaging system 270 shown in FIG. 3B captures the anterior segment of the eye E from two or more directions when the projection system 260 projects illumination light for transillumination onto the fundus oculi Ef. Configured as follows. The anterior segment imaging system 270 of this example includes anterior segment cameras 300A and 300B.

  The drive unit 280 illustrated in FIG. 3B is configured to move an optical system (data acquisition optical system) included in the data acquisition system 250. The data acquisition optical system of this example includes a group of elements constituting a measurement arm provided in the fundus camera unit 2. The drive unit 280 of this example includes a moving mechanism 150.

  The control unit 210 illustrated in FIG. 3B includes a drive control unit 2101 and a display control unit 2102. The drive control unit 2101 controls the drive unit 280. The display control unit 2102 controls the user interface 240 (display unit 241).

  The configuration of an exemplary data processing unit 230 is shown in FIG. 3B. The data processing unit 230 of this example includes a position information acquisition unit 231, a reflected image removal unit 232, an image synthesis unit 233, a turbid area specifying unit 234, and a movement target determination unit 235.

<Position information acquisition unit 231>
The position information acquisition unit 231 is configured to acquire position information of the eye E by analyzing two or more anterior segment images corresponding to two or more directions acquired by the anterior segment imaging system 270. . The position information acquisition unit 231 analyzes, for example, two anterior eye images acquired by the two anterior eye cameras 300 imaging the anterior eye part of the eye E substantially simultaneously, and thereby the eye E to be examined. Is obtained. An example of processing executed by the position information acquisition unit 231 will be described below.

  First, the position information acquisition unit 231 can correct the distortion of the captured image obtained by the anterior eye camera 300 based on the aberration information stored in the storage unit 212. This correction can be performed by, for example, a known image processing technique based on a correction coefficient for correcting distortion. In addition, when the distortion aberration given to the captured image by the optical system of the anterior segment camera 300 is sufficiently small, aberration information and correction using the aberration information may not be necessary.

  Next, the position information acquisition unit 231 can specify an image region (pupil region) corresponding to the pupil of the eye E based on the distribution of pixel values (for example, luminance values) of the captured image. In general, since the pupil is expressed with a lower luminance than other parts, it is possible to specify the pupil region by searching for a low luminance image region. At this time, the pupil region may be specified in consideration of the shape of the pupil. For example, the pupil region can be specified by searching for a substantially circular and low-luminance image region.

  Subsequently, the position information acquisition unit 231 can specify the center position of the specified pupil region. As described above, using the fact that the pupil is substantially circular, the position information acquisition unit 231 includes, for example, processing for specifying the contour of the pupil region, processing for obtaining an approximate ellipse (or approximate circle) of the contour, And processing for specifying the center position of the approximate ellipse (or approximate circle). The center position of the approximate ellipse (or approximate circle) specified in this way is used as the pupil center of the eye E. As another example of the processing for obtaining the pupil center, the position information acquisition unit 231 can obtain the center of gravity of the pupil region and set it to the pupil center.

  The position information acquisition unit 231 determines the center of the pupil of the eye E based on the position of the anterior segment camera 300 (and the imaging magnification) and the position of the center of the pupil in the two captured images specified in the previous process. A three-dimensional position can be obtained.

  FIG. 5A is a top view showing a positional relationship among the eye E, the anterior eye camera 300A, and the anterior eye camera 300B. FIG. 5B is a side view showing the positional relationship among the eye E, the anterior eye camera 300A, and the anterior eye camera 300B. The distance (baseline length) between the anterior eye camera 300A and the anterior eye camera 300B is represented by “B”. A distance (imaging distance) between the baselines of the anterior eye cameras 300A and 300B and the pupil center P of the eye E is represented by “H”. The distance (screen distance) between the anterior eye camera 300A and its screen plane is represented by “f”.

  In such an arrangement state, the resolution of the image captured by the anterior eye cameras 300A and 300B is expressed by the following equation. Here, Δp represents pixel resolution.

Resolution in xy direction (planar resolution): Δxy = H × Δp / f
Resolution in the z direction (depth resolution): Δz = H × H × Δp / (B × f)

  The positional information acquisition unit 231 has, for example, the positional relationship shown in FIGS. 5A and 5B with respect to the positions (known) of the anterior eye cameras 300A and 300B and the position corresponding to the pupil center P in the two captured images. By applying a well-known trigonometric method considering the above, the three-dimensional position of the pupil center P can be calculated.

  Even when feature points other than the center of the pupil are applied, the position information acquisition unit 231 applies the same processing as described above, so that the three-dimensional feature points are obtained based on the distribution of pixel values of the captured image. It is possible to determine the position.

  The position information acquired by the position information acquisition unit 231 (for example, information indicating the three-dimensional position of the pupil center) is sent to the control unit 210. The drive control unit 2101 applies alignment control based on this position information to the drive unit 280. This alignment control is an example of the above-described auto alignment. After the automatic alignment, the control unit 210 controls the projection system 260 to project illumination light for transillumination onto the eye E (fundus Ef).

<Reflected image removing unit 232>
As described above, in the conventional technique, when illumination light for transillumination is incident through the corneal apex of the eye E, the presence or absence of turbidity is confirmed by the corneal reflection image (bright spot) mixed in the transillumination image. It becomes difficult. Therefore, although the amount of illumination light can be used efficiently, illumination through the corneal apex cannot be applied in transillumination photography.

  On the other hand, according to the ophthalmologic apparatus 1, it is possible to confirm the presence or absence of turbidity by removing the corneal reflection image from the transillumination image even if the illumination light is projected through the apex of the cornea and the transillumination is performed. . The reflected image removing unit 232 executes processing for removing a corneal reflection image of illumination light for transillumination shooting from the anterior ocular segment image.

  The incident position of illumination light for transillumination photography is not limited to the path through the corneal apex, and may be an arbitrary position. For example, when there is an abnormality (for example, turbidity or pigmentation) on the path through the corneal apex, such as when the eye E has a nuclear cataract, it is possible to apply a path that deviates from the corneal apex. is there.

  The reflected image removing unit 232 analyzes two or more anterior segment images acquired by the anterior segment imaging system 270, and cornea caused by illumination light for transillumination imaging from each of these anterior segment images. Remove the reflected image. For example, the reflected image removing unit 232 compares the first anterior ocular segment image and the second anterior ocular segment image among the two or more anterior ocular segment images acquired by the anterior ocular segment imaging system 270, The cornea reflection image mixed in the first anterior segment image can be removed.

In this example, the reflected image removing unit 232 analyzes the first anterior segment image acquired by the anterior segment camera 300A and the second anterior segment image acquired by the anterior segment camera 300B. First, the reflected image removing unit 232 specifies a position (pixel) in the second anterior segment image corresponding to the position (pixel) of the corneal reflection image in the first anterior segment image. Further, the reflected image removing unit 232 identifies a position (pixel) in the first anterior segment image corresponding to the position (pixel) of the corneal reflection image in the second anterior segment image.
Such identification of the corresponding pixels can be performed by applying a known trigonometry method considering the arrangement state shown in FIGS. 5A and 5B, for example.

  Since the anterior segment cameras 300A and 300B are arranged so as to photograph the anterior segment from different directions, in the second anterior segment image corresponding to the corneal reflection image in the first anterior segment image. There is no corneal reflection image at the position, and there is no corneal reflection image at the position in the first anterior segment image corresponding to the corneal reflection image in the second anterior segment image. In this example, the corneal reflection image exists at a position different from the position in the second anterior eye image corresponding to the corneal reflection image in the first anterior eye image, and the second anterior eye image. The arrangement of the anterior segment cameras 300A and 300B can be designed in advance so that the corneal reflection image exists at a position different from the position in the first anterior segment image corresponding to the corneal reflection image.

  Next, the reflected image removing unit 232 replaces the pixel of the corneal reflection image in the first anterior segment image with the corresponding pixel in the second anterior segment image. Further, the reflected image removing unit 232 replaces the pixel of the corneal reflection image in the second anterior ocular segment image with the corresponding pixel in the first anterior ocular segment image. By such processing, the corneal reflection image is removed from the first anterior segment image, and the removed image area is the image region (not the corneal reflection image) in the corresponding second anterior segment image. ). Similarly, the corneal reflection image is removed from the second anterior ocular segment image, and the removed image area is replaced with the corresponding image area (not the corneal reflection image) in the first anterior ocular segment image. can do. Thereby, two anterior ocular segment images not including a cornea reflection image are obtained.

<Image composition unit 233>
The image composition unit 233 forms a composite image based on two or more anterior segment images from which the cornea reflection image has been removed by the reflection image removal unit 232. The composite image may be an image in any form that can be constructed based on two or more anterior segment images.

  The composite image may be a front image, for example. The front image is, for example, a two-dimensional image defined in a coordinate system orthogonal to the optical axis of the optical system (data acquisition optical system) included in the data acquisition system 250. In this example, the front image is, for example, a two-dimensional image defined in an xy coordinate system orthogonal to the optical axis (objective optical axis) of the objective lens 22.

  The image synthesizing unit 233 can execute known image processing for synthesizing two or more images. This image processing (image synthesis) includes, for example, known viewpoint conversion in consideration of the arrangement state shown in FIGS. 5A and 5B. Alternatively, the image composition may include a known three-dimensional image construction considering the arrangement state shown in FIGS. 5A and 5B and a rendering for constructing a two-dimensional image from the three-dimensional image data constructed thereby. . This rendering may include, for example, a projection based on 3D image data defined in the xyz coordinate system.

  The image combining unit 233 can also combine two or more anterior segment images acquired by the anterior segment imaging system 270. Further, after removing the corneal reflection image from a part of the two or more anterior segment images, one or more anterior segment images from which the corneal reflection image has been removed and one or more anterior eyes from which the corneal reflection image has not been removed. It is also possible to synthesize a partial image. Such a composite image includes, for example, a corneal reflection image resulting from each anterior segment image subjected to the synthesis process.

  The reflected image removal unit 232 can remove the corneal reflection image from the composite image. The removal of the corneal reflection image from the composite image can be executed, for example, in the same manner as the above-described removal from the anterior segment image.

  As described above, the data processing unit 230 including the reflected image removing unit 232 and the image combining unit 233 analyzes two or more anterior segment images acquired by the anterior segment imaging system 270 to perform transillumination imaging. A composite image is formed by removing a cornea reflection image caused by illumination light. Note that the process for forming the composite image from which the cornea reflection image is removed is not limited to the example described here, and may include any image processing technique.

  The display control unit 2102 can cause the display unit 241 to display the composite image formed by the data processing unit 230. Further, the display control unit 2102 displays the anterior ocular segment image acquired by the anterior ocular segment imaging system 270 on the display unit 241, and the anterior ocular segment image from which the corneal reflection image is removed by the reflected image removing unit 232. Can be displayed on the display unit 241.

<Muddy area specifying unit 234>
The turbid region specifying unit 234 specifies the turbid region in the anterior segment image of the eye E to be examined. The turbid area is an image area corresponding to the turbidity inside the eye E. The turbid area corresponds to the turbidity of the intermediate translucent body as seen in cataract eyes.

  For example, the turbid area specifying unit 234 can specify the turbid area based on the distribution of pixel values (for example, luminance values) of the anterior segment image. A turbid spot is projected as a shadow in a transillumination image such as an anterior segment image. The turbid area specifying unit 234 specifies a pixel having a luminance value equal to or less than a predetermined threshold value by applying a threshold process related to the luminance to the anterior ocular segment image. Thus, the specified pixel group is set as a turbid area. In this threshold processing, for example, a default threshold or a threshold set according to the anterior segment image or the like is used.

  The turbid area specifying unit 234 can specify the turbid area in the anterior segment image after the corneal reflection image is removed by the reflected image removing unit 232. Thereby, the turbid region in the anterior ocular segment image can be identified without being affected by the cornea reflection image.

  The turbid region specifying unit 234 may include a composite image that does not include a cornea reflection image (for example, a composite image based on two or more anterior segment images from which the cornea reflection image has been removed, or a composite image after the cornea reflection image has been removed). It is possible to specify a turbid area in (image). Thereby, it is possible to specify the turbid region in the composite image without being affected by the cornea reflection image.

  In this way, by combining the removal of the corneal reflection image and the specification of the turbid area, the adverse effect of the corneal reflection image on the specification of the turbid area distribution can be eliminated. More specifically, in the prior art, it could not be confirmed whether or not there is turbidity at the position of the corneal reflection image. However, according to the ophthalmologic apparatus 1 according to this embodiment, the corneal reflection image is removed. Thus, since the entire pupil region can be depicted, the problems associated with the prior art do not occur.

<Moving target determination unit 235>
The movement target determination unit 235 determines a movement target of the optical system (data acquisition optical system) included in the data acquisition system 250 based on the composite image formed by the image composition unit 233. The determined movement target is used for alignment of the data acquisition optical system.

  It is assumed that the composite image input to the movement target determination unit 235 does not include a cornea reflection image, and the turbid region in the composite image has already been specified. The movement target determination unit 235 can determine the movement target of the data acquisition optical system so as to pass through a position different from the turbid area in such a composite image. That is, the movement target determination unit 235 can determine the movement target of the data acquisition optical system so that the measurement light LS projected by the data acquisition system 250 is guided while avoiding turbidity in the eye E.

  The movement target determination unit 235 can determine the movement target of the data acquisition optical system in consideration of the beam diameter of the measurement light LS. For example, the movement target determination unit 235 can determine the movement target of the data acquisition optical system so that the entire beam cross section of the measurement light LS passes through the unturbid portion.

  As described above, in order to reduce speckle noise mixed in the anterior segment image acquired by the anterior segment imaging system 270, the control unit 210 changes the deflection direction of the measurement light LS with time. The optical scanner 44 can be controlled. In this case, the movement target determination unit 235 can determine the movement target of the data acquisition optical system in consideration of the change in the passing position of the measurement light LS. For example, the movement target determination unit 235 may determine the movement target of the data acquisition optical system so that the change range of the passing position of the measurement light LS at a predetermined depth position in the eye E does not overlap with the turbid area. it can. Typically, since the optical scanner 44 is disposed at a position optically conjugate with the pupil of the eye E, the measurement light LS passes at a location relatively far from the pupil (for example, the rear surface of the crystalline lens). The moving target of the data acquisition optical system can be determined so that the position change range does not overlap with the turbid area. The distance between the pupil and the predetermined location may be, for example, a value obtained by measuring the eye E or a value obtained from model eye data.

  The movement target determined by the movement target determination unit 235 is information including at least an x coordinate and ay coordinate, for example. The determined movement target is sent to the control unit 210.

  When the alignment is automatically corrected, the drive control unit 2101 can control the drive unit 280 based on the movement target. For example, the drive control unit 2101 can control the drive unit 280 so that the data acquisition optical system is moved to a position corresponding to the x coordinate and the y coordinate included in the movement target.

  When manually correcting the alignment, the display control unit 2102 can cause the display unit 241 to display the composite image formed by the image composition unit 233, for example. Further, the display control unit 2102 can display the alignment index image together with the composite image. The operation unit 242 is used for a user to perform an alignment operation of the data acquisition optical system. The drive control unit 2101 can control the drive unit 280 based on a signal input from the operation unit 242. Thereby, the user can move the data acquisition optical system to a desired position.

  When the alignment is manually corrected, the display control unit 2102 can display information for alignment operation (alignment support information) on the display unit 241 based on the movement target determined by the movement target determination unit 235. it can. The alignment support information may include, for example, information indicating a position corresponding to the movement target displayed together with a front image (for example, a composite image) of the anterior segment. Alternatively, the alignment support information is information indicating an operation direction (movement direction) and / or an operation amount (movement amount), such as an arrow image from the current position of the data acquisition optical system to a position corresponding to the movement target. May contain. Such alignment support information is generated based on, for example, the x coordinate and the y coordinate included in the movement target.

<Operation>
An example of the operation of the ophthalmologic apparatus 1 according to this embodiment will be described. Hereinafter, an alignment correction operation that can be performed by the ophthalmologic apparatus 1 will be described.

<Automatic alignment correction>
An example of the operation for automatically correcting the alignment is shown in FIG.

(S1: Start alignment)
First, alignment of the data acquisition optical system is started. This alignment may be automatic alignment or manual alignment.

  Auto-alignment can be performed using, for example, the anterior segment imaging system 270 (anterior segment camera 300), the position information acquisition unit 231 and the drive control unit 2101 (stereo camera system). Alternatively, the auto alignment can be executed using an alignment index, for example. Note that the method of auto alignment is not limited to these, and may be any method such as a method using an optical lever or a method using a Purkinje image. Any known technique can be applied to the manual alignment.

(S2: Alignment complete)
The alignment in step S1 is completed when the alignment of the data acquisition optical system with respect to the eye E falls within a predetermined allowable range.

  For example, according to the stereo camera type auto-alignment in this embodiment, the optical axis of the data acquisition optical system substantially coincides with the center of the pupil of the eye E to be examined (alignment in the xy direction), and the eye E and the data to be examined The distance to the acquisition optical system (for example, the objective lens 22) is substantially matched to a predetermined working distance (z-direction alignment).

  In the case of manual alignment, for example, the user inputs an alignment completion instruction using the operation unit 242. Alternatively, the ophthalmologic apparatus 1 detects that the alignment of the data acquisition optical system with respect to the eye E has been guided within a predetermined allowable range by manual alignment.

  Upon completion of the alignment, known tracking for moving the data acquisition optical system in accordance with the movement of the eye E may be started.

(S3: An anterior segment image group is obtained by performing transillumination imaging with the anterior segment imaging system)
Upon completion of the alignment, the control unit 210 performs control for transillumination imaging of the eye E.

  For example, the control unit 210 controls the projection system 260 to project illumination light for transillumination shooting onto the eye E. In this example, measurement light LS for OCT is used as illumination light for transillumination photography. Since the alignment is completed in step S2, the measurement light LS is projected on the center of the pupil of the eye E or in the vicinity thereof. That is, the measurement light LS is projected to the corneal apex or its vicinity. Thereby, a bright fundus reflection is obtained.

  The transillumination using the fundus reflection by the measurement light LS is performed using the anterior segment imaging system 270 (fundus cameras 300A and 300B). According to this transillumination, two or more anterior segment images (anterior segment image group) are obtained as a transillumination image.

(S4: Remove cornea reflection image from each anterior segment image)
The reflected image removing unit 232 analyzes the anterior segment image group acquired in step S3 and removes the corneal reflected image caused by illumination light (measurement light LS) for transillumination from each anterior segment image. To do.

(S5: A front image is formed by synthesizing an anterior segment image group)
The image combining unit 233 combines the anterior ocular segment images from which the cornea reflection images have been removed in step S4 to form a front image of the anterior segment of the eye E to be examined.

  The display control unit 2102 can display the front image on the display unit 241.

(S6: Specify the turbid area in the front image)
The turbid area specifying unit 234 analyzes the front image formed in step S5 and specifies the turbid area.

  The display control unit 2102 can cause the display unit 241 to display information indicating the turbid area together with the front image.

(S7: Determine the movement target of the data acquisition optical system)
The movement target determination unit 235 determines a movement target of the data acquisition optical system based on the turbid area specified in step S6.

  The movement target determination unit 235 determines the movement target so that the optical axis (measurement light LS) of the data acquisition optical system passes through a position different from the turbid area. As described above, in determining the movement target, the beam diameter of the measurement light LS and / or the deflection range of the measurement light LS for speckle noise reduction may be considered.

  The display control unit 2102 can display information indicating the movement target on the display unit 241 together with information indicating the front image and / or the turbid area.

(S8: Move the data acquisition optical system)
The drive control unit 2101 controls the drive unit 280 to move the optical axis of the data acquisition optical system to the position (x coordinate, y coordinate) indicated by the movement target determined in step S7.

(S9: Execute OCT)
When the movement of the data acquisition optical system in step S8 is completed, the control unit 210 controls the data acquisition system 250 to perform OCT for the eye E. Thus, the operation illustrated in FIG. 6 is completed.

<Manual alignment correction>
An example of an operation for automatically correcting the alignment is shown in FIG.

(S11-S17)
Steps S11 to S17 are executed in the same manner as steps S1 to S7 in FIG. 6 (automatic correction), respectively.

(S18: Display front image)
The display control unit 2102 causes the display unit 241 to display the front image formed in step S15. In addition, the display control unit 2102 can cause the display unit 241 to display information indicating the turbid area specified in step S16 together with the front image.

(S19: Display alignment support information)
The display control unit 2102 causes the display unit 241 to display alignment support information based on the movement target determined in step S17 together with the front image (and information indicating the turbid area).

(S20: User performs alignment operation)
The user performs an operation of correcting the alignment of the data acquisition optical system using the operation unit 242 while referring to the front image displayed on the display unit 241 and the alignment support information (and information indicating the turbid area). .

(S21: Perform OCT)
For example, when the user inputs an alignment correction completion instruction or an OCT start instruction using the operation unit 242, the control unit 210 controls the data acquisition system 250 to execute OCT for the eye E. Alternatively, when the ophthalmologic apparatus 1 detects the completion of alignment correction, the control unit 210 controls the data acquisition system 250 to execute OCT for the eye E. This completes the operation illustrated in FIG.

<Modification>
A modification of the above embodiment will be described.

  In the above embodiment, automatic alignment correction is performed using a composite image based on two or more anterior segment images. However, the embodiment is configured to automatically correct alignment without forming a composite image. It is also possible to apply a form.

  For example, the opacity region specifying unit 234 analyzes each anterior segment image acquired by the anterior segment imaging system 270 (anterior segment camera 300) and identifies the turbid region in each anterior segment image. The movement target determination unit 235 moves the data acquisition optical system based on the turbidity region specified for each anterior segment image by applying, for example, a well-known trigonometric method considering the arrangement state shown in FIGS. 5A and 5B. A goal can be determined. Here, the corneal reflection image in each anterior ocular segment image is removed by the same processing as the reflected image removing unit 232, and the moving target is determined based on the turbid region in the anterior ocular segment image group from which each corneal reflection image has been removed. You may make it do. The drive control unit 2101 controls the drive unit 280 based on the movement target determined as described above, whereby automatic alignment correction according to this modification can be realized.

<effect>
The effect which this embodiment has is explained.

  An ophthalmologic apparatus (1) according to this embodiment is an apparatus for optically acquiring data of an eye to be examined (E), and includes a projection system (260), an anterior ocular imaging system (270), and image processing. (Data processing unit 230). The data of the eye to be examined optically acquired by the ophthalmologic apparatus (1) may be, for example, image data or characteristic measurement data.

  The projection system (260) projects illumination light for transillumination photographing on the fundus (Ef) of the eye to be examined (E). In the above exemplary embodiment, the illumination light for transillumination may be the measurement light LS for OCT.

  The anterior segment imaging system (270) images the anterior segment of the eye to be examined (E) in which illumination light for transillumination imaging is projected onto the fundus (Ef) from two or more directions. In the exemplary embodiment described above, the anterior segment imaging system (270) includes two anterior segment cameras 300A and 300B disposed at different positions, and images the anterior segment at substantially the same time to capture the two anterior segments. An eye image can be acquired.

  The image processing unit (the data processing unit 230, the turbid region specifying unit 234) analyzes two or more anterior segment images corresponding to two or more directions acquired by the anterior segment imaging system (270), and detects the eye to be examined. A turbid area corresponding to the turbidity inside (E) is specified. In the exemplary embodiment, the turbid area can be specified by the turbid area specifying unit 234.

  In the ophthalmologic apparatus (1) according to this embodiment, the image processing unit (data processing unit 230) displays two or more anterior segment images corresponding to two or more directions acquired by the anterior segment imaging system (270). It may be configured to form a composite image based on two or more anterior segment images from which the corneal reflection image caused by illumination light for transillumination photography is removed by analysis.

  In the ophthalmologic apparatus (1) according to this embodiment, the image processing unit (data processing unit 230) may include a reflected image removing unit (232) and an image composition unit (233). The reflected image removing unit (232) analyzes two or more anterior eye images corresponding to two or more directions acquired by the anterior eye imaging system (270), and illuminates each of these anterior eye images. A cornea reflection image caused by illumination light for photographing is removed. The image composition unit (233) forms a composite image based on the two or more anterior segment images from which the corneal reflection image has been removed by the reflection image removal unit (232).

  Conversely, in the ophthalmologic apparatus (1) according to this embodiment, a composite image is formed based on two or more anterior segment images from which the cornea reflection image has not been removed, and the cornea reflection image is removed from this composite image. May be.

  In the ophthalmologic apparatus (1) according to this embodiment, the image processing unit (data processing unit 230) generates two or more anterior segment images corresponding to two or more directions acquired by the anterior segment imaging system (270). A front image of the anterior ocular segment may be formed as a composite image based on it.

  According to such an ophthalmologic apparatus (1), it is configured to identify a turbid region based on two or more anterior segment images in transillumination, so even if illumination light is incident through the apex of the cornea, It is possible to remove the cornea reflection image caused by the illumination light. As a result, bright fundus reflection can be ensured by efficiently using the amount of illumination light, and a high-quality transillumination image can be obtained while ensuring the safety of the eye to be examined. Therefore, the ophthalmologic apparatus (1) provides an improvement in the transillumination method for appropriately grasping the turbid spot in the eye to be examined.

  The ophthalmologic apparatus (1) according to this embodiment includes a data acquisition optical system (data acquisition system 250), a drive unit (280), and a drive control unit (2101). The data acquisition optical system (data acquisition system 250) is an optical system for optically acquiring data of the eye to be examined (E). The drive unit (280) moves the data acquisition optical system (data acquisition system 250). The drive control unit (2101) controls the drive unit (280). The image processing unit (data processing unit 230) includes a first movement target determination unit (movement target determination unit 235). The first movement target determination unit (movement target determination unit 235) is configured to generate a data acquisition optical system (data acquisition system) based on a composite image based on two or more anterior segment images acquired by the anterior segment imaging system (270). 250) is determined. The drive control unit (2101) controls the drive unit (280) based on the determined movement target.

  According to such a configuration, it is possible to automatically perform alignment correction using a composite image based on two or more anterior segment images. That is, it is possible to automatically correct the alignment of the data acquisition optical system so as to acquire the data of the eye to be examined while avoiding the cloudy portion in the eye to be examined.

  The ophthalmologic apparatus (1) according to this embodiment may include a display control unit (2102). The display control unit (2102) causes the display means (display unit 241) to display a composite image based on two or more anterior segment image acquired by the anterior segment imaging system (270).

  According to such a configuration, the user can observe the composite image as a transillumination image, and can grasp the cloudy portion of the eye to be examined.

  The ophthalmologic apparatus (1) according to this embodiment includes a data acquisition optical system (data acquisition system 250), a drive unit (280), a display control unit (2102), an operation unit (242), and a drive control unit ( 2101). The data acquisition optical system (data acquisition system 250) is an optical system for optically acquiring data of the eye to be examined (E). The drive unit (280) moves the data acquisition optical system (data acquisition system 250). The display control unit (2102) causes the display means (display unit 241) to display a composite image based on two or more anterior segment image acquired by the anterior segment imaging system (270). The operation unit (242) is used to perform an alignment operation of the data acquisition optical system (data acquisition system 250). The drive control unit (2101) controls the drive unit (280) based on a signal from the operation unit (242).

  According to such a configuration, it is possible to manually perform alignment correction using a composite image based on two or more anterior segment images. That is, it is possible to manually correct the alignment of the data acquisition optical system so as to acquire the data of the eye to be examined while avoiding the cloudy portion in the eye to be examined.

  In the ophthalmologic apparatus (1) according to this embodiment, the image processing unit (data processing unit 230) includes a first movement target determination unit (movement target determination unit 235). The first movement target determination unit (movement target determination unit 235) is configured to generate a data acquisition optical system (data acquisition system) based on a composite image based on two or more anterior segment images acquired by the anterior segment imaging system (270). 250) is determined. The display control unit (2102) causes the display means (display unit 241) to display information for alignment operation (alignment support information) based on the determined movement target.

  According to such a configuration, it is possible to facilitate manual correction of the alignment of the data acquisition optical system.

  The ophthalmologic apparatus (1) according to this embodiment includes a data acquisition optical system (data acquisition system 250), a drive unit (280), and a drive control unit (2101). The data acquisition optical system (data acquisition system 250) is an optical system for optically acquiring data of the eye to be examined (E). The drive unit (280) moves the data acquisition optical system (data acquisition system 250). The drive control unit (2101) controls the drive unit (280). The image processing unit (data processing unit 230) includes a position information acquisition unit (231). The position information acquisition unit (231) analyzes the two or more anterior segment images corresponding to the two or more directions acquired by the anterior segment imaging system (270) and acquires the position information of the eye to be examined (E). . The drive control unit (2101) applies alignment control based on the acquired position information to the drive unit (280). After this alignment control, the projection system (260) projects illumination light for transillumination onto the fundus (Ef).

  According to such a configuration, it is possible to correct the alignment using illumination light for transillumination after aligning the data acquisition optical system by stereo camera auto-alignment.

  The ophthalmologic apparatus (1) according to this embodiment includes a data acquisition optical system (data acquisition system 250), a drive unit (280), and a drive control unit (2101). The data acquisition optical system (data acquisition system 250) is an optical system for optically acquiring data of the eye to be examined (E). The drive unit (280) moves the data acquisition optical system (data acquisition system 250). The drive control unit (2101) controls the drive unit (280). The image processing unit (data processing unit 230) includes a second movement target determination unit (movement target determination unit 235). The second movement target determination unit (movement target determination unit 235) is based on the turbid region specified by the image processing unit (data processing unit 230, turbid region specifying unit 234) of the data acquisition optical system (data acquisition system 250). Determine the movement target. The drive control unit (2101) controls the drive unit (280) based on the determined movement target.

  According to such a configuration, it is possible to automatically perform alignment correction without forming a composite image. That is, it is possible to automatically correct the alignment of the data acquisition optical system so as to acquire the data of the eye to be examined while avoiding the cloudy portion in the eye to be examined.

  In the ophthalmologic apparatus (1) according to this embodiment, the image processing unit (data processing unit 230) analyzes two or more anterior segment images acquired by the anterior segment imaging system (270), and these anterior segment A cornea reflection image caused by illumination light for transillumination photographing may be removed from at least one anterior segment image of the partial images.

  According to such a configuration, when illumination light for transillumination is incident through the apex of the cornea, an anterior ocular segment image (transillumination image) from which the cornea reflection image resulting from the illumination light has been removed is obtained. It is possible to obtain.

  In the ophthalmologic apparatus (1) according to this embodiment, the projection system (260) projects light for acquiring data of the eye to be examined (E) onto the fundus (Ef) as illumination light for transillumination photography. Also good.

  The ophthalmologic apparatus (1) according to this embodiment may include an optical scanner (44) for acquiring data of the eye to be examined (E) by optical scanning. Further, the projection system (260) may project illumination light for transillumination photography onto the fundus (Ef) via the optical scanner (44).

  The ophthalmologic apparatus (1) according to this embodiment may include an OCT unit (data acquisition system 250). The OCT unit projects measurement light (LS) onto the fundus (Ef) via the optical scanner (44), and superimposes return light of the measurement light (LS) on the reference light (LR) to generate interference light (LC). Generate data based on the detection result of the interference light (LC). The projection system (260) projects measurement light (LS) onto the fundus (Ef) as illumination light for transillumination photography.

  In the ophthalmologic apparatus (1) according to this embodiment, the optical scanner (44) can reduce speckle noise by temporally changing the deflection direction of illumination light for transillumination. is there.

  Another aspect of this embodiment is an ophthalmologic apparatus (1) for optically acquiring data of an eye to be examined (E), which includes a projection system (260), an anterior ocular segment imaging system (270), And an image processing unit (data processing unit 230). The projection system (260) projects illumination light for transillumination photographing on the fundus (Ef) of the eye to be examined (E). The anterior ocular segment imaging system (270) captures an anterior segment of the subject's eye in which illumination light for transillumination is projected on the fundus (Ef) from two or more directions. The image processing unit (data processing unit 230) analyzes two or more anterior segment images corresponding to two or more directions acquired by the anterior segment imaging system (270), and illuminates light for transillumination imaging. A composite image based on two or more anterior segment images from which the corneal reflection image resulting from the above has been removed is formed.

  According to such an ophthalmologic apparatus (1), it is possible to obtain a composite image from which a cornea reflection image is removed even when illumination light is incident through the apex of the cornea in transillumination. Thereby, the improvement of the transillumination method for grasping | ascertaining the turbid location in a to-be-examined eye suitably is provided.

  The aspect described above is merely an example of the implementation of the present invention. A person who intends to implement the present invention can make arbitrary modifications (omission, replacement, addition, etc.) within the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Ophthalmology apparatus 210 Control part 2101 Drive control part 2102 Display control part 230 Data processing part 231 Position information acquisition part 232 Reflection image removal part 233 Image composition part 234 Cloudy area specification part 235 Movement target determination part 240 User interface 250 Data acquisition system 260 Projection system 270 Anterior segment imaging system 280 Drive unit E Eye Ef Fundus

Claims (16)

An ophthalmologic apparatus for optically acquiring data of an eye to be examined,
A projection system that projects illumination light for transillumination onto the fundus of the eye to be examined;
An anterior ocular segment imaging system for imaging the anterior ocular segment of the eye under examination in which the illumination light is projected onto the fundus;
An image processing unit that analyzes two or more anterior segment images corresponding to the two or more directions acquired by the anterior segment imaging system and identifies a turbid region corresponding to turbidity inside the eye to be examined;
Ophthalmic device. The image processing unit analyzes the two or more anterior segment images and forms a composite image based on the two or more anterior segment images from which a corneal reflection image caused by the illumination light is removed;
The ophthalmic apparatus according to claim 1. The image processing unit
A reflected image removing unit that analyzes the two or more anterior segment images and removes a corneal reflection image caused by the illumination light from each of the two or more anterior segment images;
An image composition unit that forms the composite image based on the two or more anterior segment images from which the cornea reflection image has been removed by the reflection image removal unit;
including,
The ophthalmic apparatus according to claim 2. The image processing unit forms a front image of the anterior segment as the composite image;
The ophthalmologic apparatus according to claim 3. A data acquisition optical system for optically acquiring the data;
A drive unit for moving the data acquisition optical system;
A drive control unit for controlling the drive unit;
Further including
The image processing unit includes a first movement target determination unit that determines a movement target of the data acquisition optical system based on the composite image,
The drive control unit controls the drive unit based on the movement target;
The ophthalmologic apparatus according to any one of claims 2 to 4, wherein A display control unit for displaying the composite image on a display unit;
The ophthalmologic apparatus according to any one of claims 2 to 5, wherein A data acquisition optical system for optically acquiring the data;
A drive unit for moving the data acquisition optical system;
A display control unit for displaying the composite image on a display unit;
An operation unit for performing an alignment operation of the data acquisition optical system;
A drive control unit for controlling the drive unit based on a signal from the operation unit;
Further including
The ophthalmologic apparatus according to any one of claims 2 to 4, wherein The image processing unit includes a first movement target determination unit that determines a movement target of the data acquisition optical system based on the composite image,
The display control unit causes the display unit to display information for the alignment operation based on the movement target.
The ophthalmic apparatus according to claim 7. A data acquisition optical system for optically acquiring the data;
A drive unit for moving the data acquisition optical system;
A drive control unit for controlling the drive unit;
Further including
The image processing unit includes a position information acquisition unit that analyzes two or more anterior segment images corresponding to the two or more directions acquired by the anterior segment imaging system and acquires positional information of the eye to be examined. ,
The drive control unit applies alignment control based on the position information to the drive unit,
After the alignment control, the projection system projects the illumination light onto the fundus.
The ophthalmic apparatus according to claim 1. A data acquisition optical system for optically acquiring the data;
A drive unit for moving the data acquisition optical system;
A drive control unit for controlling the drive unit;
The image processing unit includes a second movement target determination unit that determines a movement target of the data acquisition optical system based on the turbid area,
The drive control unit controls the drive unit based on the movement target;
The ophthalmic apparatus according to claim 1. The image processing unit analyzes the two or more anterior segment images and removes a corneal reflection image caused by the illumination light from at least one anterior segment image of the two or more anterior segment images. ,
The ophthalmic apparatus according to claim 1. The projection system projects light for acquiring the data onto the fundus as the illumination light.
The ophthalmologic apparatus according to any one of claims 1 to 11. An optical scanner for acquiring the data by optical scanning;
The projection system projects the illumination light onto the fundus via the optical scanner.
The ophthalmic apparatus according to claim 12. An OCT unit that projects measurement light onto the fundus through the optical scanner, generates interference light by superimposing return light of the measurement light on reference light, and generates the data based on the detection result of the interference light Further including
The projection system projects the measurement light onto the fundus as the illumination light.
The ophthalmic apparatus according to claim 13. The optical scanner temporally changes the deflection direction of the illumination light;
The ophthalmologic apparatus according to claim 13 or 14, characterized in that An ophthalmologic apparatus for optically acquiring data of an eye to be examined,
A projection system that projects illumination light for transillumination onto the fundus of the eye to be examined;
An anterior ocular segment imaging system for imaging the anterior ocular segment of the eye under examination in which the illumination light is projected onto the fundus;
The two or more anterior eyes obtained by analyzing the two or more anterior eye images corresponding to the two or more directions acquired by the anterior eye imaging system and removing a corneal reflection image caused by the illumination light An image processing unit for forming a composite image based on the partial image;
Ophthalmic device.

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