JP7030577B2 - Ophthalmic equipment - Google Patents

Description

The present invention relates to an ophthalmic apparatus.

Ophthalmic devices that can perform multiple tests and measurements on the eye to be inspected are known. Examinations and measurements for the eye to be inspected include subjective examinations and objective measurements. The subjective test obtains the result based on the response from the subject. Objective measurement obtains information about the eye to be inspected mainly by using a physical method without referring to the response from the subject.

For example, Patent Document 1 discloses an ophthalmic apparatus capable of subjective examination, measurement of refractive power of an eye to be inspected, and imaging and measurement using optical coherence tomography. Such an ophthalmic apparatus is provided with, for example, an observation optical system for observing the anterior segment of the eye to be inspected and the fundus. By sharing the observation optical system with a plurality of optical systems, each of which corresponds to an examination type (measurement type), it is possible to reduce the size of the ophthalmic apparatus. The plurality of optical systems are wavelength-separated by, for example, a dichroic mirror.

It is known that the transmission characteristic (reflection characteristic) of a dichroic mirror that performs wavelength separation changes depending on the angle of incidence of light on the dichroic mirror. When the transmission characteristics of the dichroic mirror change, the accuracy of wavelength separation decreases. For example, Patent Document 2 is caused by the dependence of the incident angle of the measured light on the dichroic mirror by devising the optical arrangement of the optical scanner that scans the measured light for performing optical coherence stromography and the dichroic mirror. A method for reducing fluctuations in wavelength separation characteristics is disclosed.

Japanese Unexamined Patent Publication No. 2017-136215 Japanese Unexamined Patent Publication No. 2014-21155

In examinations and measurements using ophthalmic appliances, light in the wavelength range in the near infrared region is often used in order to reduce the burden on the subject. Therefore, for example, the wavelength range of light used in optical coherence tomography may be close to the wavelength range of light used in an observation system. In this case, it is difficult to separate the wavelength of light in the optimum wavelength range for each optical system by using an optical member such as a dichroic mirror by the conventional method.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a new technique for performing a plurality of measurements and inspections by performing wavelength separation.

A first aspect of the ophthalmologic apparatus according to some embodiments is an objective lens, an anterior segment observation system that detects a first return light of illumination light from the anterior segment of the subject eye via the objective lens. In an inspection optical system that projects light onto the eye to be inspected through the objective lens and detects a second return light from the eye to be inspected, and an optical path synthesis surface arranged at an angle with respect to the optical axis of the objective lens. The illumination light in a wavelength range including a light path synthesizing member that synthesizes the optical path of the inspection optical system and the optical path of the anterior segment observation system and a wavelength corresponding to the incident angle of the first return light with respect to the optical path synthesis surface. Includes an anterior segment illumination system that illuminates the anterior segment.

In the second aspect of the ophthalmic apparatus according to some embodiments, in the first aspect, the anterior ocular segment illumination system has the incident angle with respect to the reference transmission center wavelength based on the light transmission characteristics on the optical path synthesis surface. The anterior segment is illuminated with illumination light in a wavelength range including a peak wavelength corresponding to the transmission center wavelength whose wavelength is shifted by the corresponding shift.

In a third aspect of the ophthalmologic apparatus according to some embodiments, in the first or second aspect, the optical path composite surface has an incident end surface of light so as to compensate for the incident angle dependence of the second return light. The optical film is formed so that the film thickness changes according to the position of.

In the fourth aspect of the ophthalmologic apparatus according to some embodiments, in the first aspect, the optical path synthesis surface depends on the position of the incident end surface of the light so as to compensate for the incident angle dependence of the second return light. The optical film is formed so that the film thickness changes, and the anterior segment illumination system receives the first return light with respect to the optical path synthesis surface with respect to the reference transmission center wavelength based on the light transmission characteristics of the optical path synthesis surface. The first peak wavelength corresponding to the first transmission center wavelength whose wavelength is shifted by the shift corresponding to the upper end of the incident angle, and the shift portion corresponding to the lower end of the incident angle with respect to the optical path synthesis surface with respect to the reference transmission center wavelength. The anterior segment is illuminated with illumination light in a wavelength range including the second peak wavelength corresponding to the second transmission center wavelength whose wavelength is shifted.

In a fifth aspect of the ophthalmic apparatus according to some embodiments, in the fourth aspect, the inspection optical system divides the light from the light source into reference light and measurement light, and the eye to be inspected via the objective lens. Includes an interference optical system that projects the measurement light and detects the interference light between the return light of the measurement light from the eye to be inspected and the reference light.

In the sixth aspect of the ophthalmologic apparatus according to some embodiments, in the fifth aspect, the interference optical system divides the light from the wavelength sweep light source into reference light and measurement light, and the measurement light is applied to the eye to be inspected. Is projected, and the interference light between the return light of the measurement light from the subject eye and the reference light is detected.

In the seventh aspect of the ophthalmologic apparatus according to some embodiments, in any of the fourth to sixth aspects, the anterior segment illumination system irradiates illumination light in a wavelength range including the first peak wavelength. It includes a first illumination light source and a second illumination light source that irradiates illumination light in a wavelength range including the second peak wavelength.

According to the present invention, it is possible to provide a new technique for performing a plurality of measurements and inspections by performing wavelength separation.

It is a schematic diagram which shows the structural example of the optical system of the ophthalmic apparatus which concerns on embodiment. It is a schematic diagram which shows the structural example of the optical system of the ophthalmic apparatus which concerns on embodiment. It is a schematic diagram for demonstrating the incident angle dependence of the dichroic mirror which concerns on embodiment. It is a schematic diagram for demonstrating the optical system of the ophthalmologic apparatus which concerns on embodiment. It is a schematic diagram for demonstrating the optical system of the ophthalmic apparatus which concerns on embodiment. It is a schematic diagram for demonstrating the ophthalmic apparatus which concerns on embodiment. It is a schematic diagram for demonstrating the structure of the ophthalmic apparatus which concerns on embodiment. It is a schematic diagram for demonstrating the structure of the ophthalmic apparatus which concerns on embodiment. It is a schematic diagram for demonstrating the structure of the ophthalmic apparatus which concerns on embodiment. It is a schematic diagram which shows the structural example of the processing system of the ophthalmic apparatus which concerns on embodiment. It is a schematic diagram which shows the flow of the operation example of the ophthalmologic apparatus which concerns on embodiment.

An example of an embodiment of the ophthalmic apparatus according to the present invention will be described in detail with reference to the drawings. It should be noted that the description contents of the documents cited in this specification and arbitrary known techniques can be incorporated into the following embodiments.

The ophthalmic apparatus according to the embodiment can perform objective measurement while observing the eye to be inspected. Observation sites of the eye to be inspected include the anterior eye and the posterior eye. Objective measurement is a measurement method for acquiring information about an eye to be inspected mainly by using a physical method without referring to a response from the subject. Objective measurement includes measurement for acquiring the characteristics of the eye to be inspected and photographing for acquiring an image of the eye to be inspected. Objective measurement includes objective refraction measurement, corneal shape measurement, intraocular pressure measurement, fundus photography, optical interference measurement and the like.

The ophthalmologic apparatus according to some embodiments can perform a subjective test while observing the eye to be inspected. The subjective test is a measurement method for acquiring information by using the response from the subject. The subjective test includes a subjective refraction measurement such as a distance test, a near test, a contrast test, and a glare test, and a visual field test.

Hereinafter, the fundus conjugate position is a position optically coupled to the fundus of the eye to be inspected in a state where the alignment is completed, and means a position optically coupled to the fundus of the eye to be inspected or its vicinity thereof. Similarly, the pupil-coupled position is a position that is optically coupled to the pupil of the eye to be inspected in the state where the alignment is completed, and means a position that is optically coupled to or in the vicinity of the pupil of the eye to be inspected. ..

<Composition of optical system>
FIG. 1 shows a configuration example of an optical system of an ophthalmic apparatus according to an embodiment. The ophthalmic apparatus 1000 according to the embodiment includes an optical system for observing the eye E to be inspected, an optical system for inspecting the eye E to be inspected, and a dichroic mirror for wavelength-separating the optical paths of these optical systems. An anterior eye portion observation system 5 is provided as an optical system for observing the eye E to be inspected. An OCT optical system and a ref measurement optical system (refractive power measurement optical system) are provided as an optical system for inspecting the eye E to be inspected.

The ophthalmic apparatus 1000 includes a Z alignment system 1, an XY alignment system 2, a kerato measurement system 3, a fixative projection system 4, an anterior ocular segment observation system 5, a reflex measurement projection system 6, a reflex measurement light receiving system 7, and an OCT optical system 8. including. In the following, for example, the anterior eye observation system uses light of 940 nm to 1000 nm, and the reflex measurement optical system (ref measurement projection system 6, reflex measurement light receiving system 7) uses light of 830 nm to 880 nm, and the fixation projection system 4 The case where the OCT optical system 8 uses the light of 1000 nm to 1100 nm and the light of 400 nm to 700 nm is used will be described.

(Anterior eye observation system 5)
The anterior eye portion observation system 5 captures a moving image of the anterior segment of the eye to be inspected E. In the optical system via the anterior eye portion observation system 5, the image pickup surface of the image pickup element 59 is arranged at the pupil conjugate position. The anterior eye portion illumination light source 50 irradiates the anterior segment of the eye E to be inspected with illumination light (for example, infrared light). The light reflected by the anterior segment of the eye E to be inspected passes through the objective lens 51, passes through the dichroic mirror 52, passes through the hole formed in the diaphragm (teressen diaphragm) 53, and passes through the half mirror 23. , Passes through the relay lenses 55 and 56, and passes through the dichroic mirror 76. The dichroic mirror 52 synthesizes (separates) the optical path of the reflex measurement optical system and the optical path of the anterior ocular segment observation system 5. In the dichroic mirror 52, the optical path synthesis surface that synthesizes these optical paths is arranged so as to be inclined with respect to the optical axis of the objective lens 51. The light transmitted through the dichroic mirror 76 is imaged on the image pickup surface of the image pickup element 59 (area sensor) by the image pickup lens 58. The image pickup device 59 performs image pickup and signal output at a predetermined rate. The output (video signal) of the image pickup device 59 is input to the processing unit 9 described later. The processing unit 9 displays the front eye portion image E'based on this video signal on the display screen 10a of the display unit 10 described later. The anterior eye portion image E'is, for example, an infrared moving image.

(Z alignment system 1)
The Z alignment system 1 projects light (infrared light) for alignment in the optical axis direction (front-back direction, Z direction) of the anterior eye portion observation system 5 onto the eye E to be inspected. The light output from the Z alignment light source 11 is projected onto the corneal Cr of the eye E to be inspected, reflected by the cornea Cr, and imaged on the sensor surface of the line sensor 13 by the imaging lens 12. When the position of the apex of the cornea changes in the optical axis direction of the anterior eye portion observation system 5, the projection position of light on the sensor surface of the line sensor 13 changes. The processing unit 9 obtains the position of the corneal apex of the eye E to be inspected based on the light projection position on the sensor surface of the line sensor 13, and controls the mechanism for moving the optical system based on this to execute Z alignment.

(XY alignment system 2)
The XY alignment system 2 emits light (infrared light) for alignment in a direction orthogonal to the optical axis of the anterior segment observation system 5 (horizontal direction (X direction), vertical direction (Y direction)). Irradiate to. The XY alignment system 2 includes an XY alignment light source 21 and a collimator lens 22 provided in an optical path branched from the optical path of the anterior eye observation system 5 by a half mirror 23. The light output from the XY alignment light source 21 passes through the collimator lens 22, is reflected by the half mirror 23, and is projected onto the eye E to be inspected through the anterior eye observation system 5. The reflected light from the corneal Cr of the eye E to be inspected is guided to the image pickup device 59 through the anterior ocular segment observation system 5.

The image (bright spot image) Br based on this reflected light is included in the anterior eye portion image E'. The processing unit 9 displays the front eye portion image E'including the bright spot image Br and the alignment mark AL on the display screen of the display unit. When manually performing XY alignment, the user operates the optical system so as to guide the bright spot image Br in the alignment mark AL. When the alignment is automatically performed, the processing unit 9 controls a mechanism for moving the optical system so that the displacement of the bright spot image Br with respect to the alignment mark AL is cancelled.

(Kerato measurement system 3)
The kerato measurement system 3 projects a ring-shaped luminous flux (infrared light) for measuring the shape of the corneal Cr of the eye E to be inspected onto the corneal Cr. The kerato plate 31 is arranged between the objective lens 51 and the eye E to be inspected. A keratling light source 32 is provided on the back surface side (objective lens 51 side) of the kerato plate 31. By illuminating the kerato plate 31 with the light from the kerat ring light source 32, a ring-shaped luminous flux is projected onto the corneal Cr of the eye E to be inspected. The reflected light (keratling image) from the corneal Cr of the eye E to be inspected is detected by the image pickup device 59 together with the anterior eye portion image E'. The processing unit 9 calculates a corneal shape parameter representing the shape of the corneal Cr by performing a known calculation based on this keratling image.

(Ref measurement projection system 6, reflex measurement light receiving system 7)
The reflex measurement optical system includes a reflex measurement projection system 6 and a reflex measurement light receiving system 7 used for refractive power measurement. The reflex measurement projection system 6 projects a luminous flux for measuring refractive power (for example, a ring-shaped luminous flux) (infrared light) onto the fundus Ef. The reflex measurement light receiving system 7 receives the return light of this luminous flux from the eye E to be inspected. The reflex measurement projection system 6 is provided in an optical path branched by a perforated prism 65 provided in the optical path of the reflex measurement light receiving system 7. The hole portion formed in the hole opening prism 65 is arranged at the pupil conjugate position. In the optical system via the reflex measurement light receiving system 7, the image pickup surface of the image pickup element 59 is arranged at the fundus conjugate position.

In some embodiments, the ref measurement light source 61 is an SLD (Superluminescent Diode) light source, which is a high-intensity light source. The reflex measurement light source 61 is movable in the optical axis direction. The reflex measurement light source 61 is arranged at the fundus conjugate position. The light output from the reflex measurement light source 61 passes through the relay lens 62 and is incident on the conical surface of the conical prism 63. The light incident on the conical surface is deflected and emitted from the bottom surface of the conical prism 63. The light emitted from the bottom surface of the conical prism 63 passes through the translucent portion formed in a ring shape on the ring diaphragm 64. The light (ring-shaped luminous flux) that has passed through the translucent portion of the ring diaphragm 64 is reflected by the reflecting surface formed around the hole portion of the perforated prism 65, passes through the rotary prism 66, and is reflected by the dichroic mirror 67. Ru. The light reflected by the dichroic mirror 67 is reflected by the dichroic mirror 52, passes through the objective lens 51, and is projected onto the eye E to be inspected. The rotary prism 66 is used for averaging the light amount distribution of the ring-shaped luminous flux with respect to the blood vessel or the diseased part of the fundus Ef and reducing the speckle noise caused by the light source.

The return light of the ring-shaped luminous flux projected on the fundus Ef passes through the objective lens 51 and is reflected by the dichroic mirror 52 and the dichroic mirror 67. The return light reflected by the dichroic mirror 67 passes through the rotary prism 66, passes through the hole portion of the perforated prism 65, passes through the relay lens 71, is reflected by the reflection mirror 72, and is reflected by the relay lens 73 and the focusing lens. Pass through 74. The focusing lens 74 can move along the optical axis of the reflex measurement light receiving system 7. The light that has passed through the focusing lens 74 is reflected by the reflection mirror 75, reflected by the dichroic mirror 76, and imaged on the image pickup surface of the image pickup element 59 by the image pickup lens 58. The processing unit 9 calculates the refractive power value of the eye E to be inspected by performing a known calculation based on the output from the image sensor 59. For example, the refractive power value includes spherical power, astigmatic power, and astigmatic axis angle.

(Fixation projection system 4)
The OCT optical system 8, which will be described later, is provided in an optical path whose wavelength is separated from the optical path of the reflex measurement optical system by the dichroic mirror 67. The fixative projection system 4 is provided in the optical path branched from the optical path of the OCT optical system 8 by the dichroic mirror 83.

The fixative projection system 4 presents the fixative to the eye E to be inspected. The liquid crystal panel 41, which is controlled by the processing unit 9, displays a pattern representing a fixative. By changing the display position of the pattern on the screen of the liquid crystal panel 41, the fixative position of the eye E to be inspected can be changed. The fixative position of the eye E to be inspected includes a position for acquiring an image centered on the macula of the fundus Ef, a position for acquiring an image centered on the optic disc, and a position between the macula and the optic disc. There is a position for acquiring an image centered on the center of the fundus between the two. It is possible to arbitrarily change the display position of the pattern representing the fixative.

The light from the liquid crystal panel 41 passes through the relay lens 42, passes through the dichroic mirror 83, passes through the relay lens 82, is reflected by the reflection mirror 81, is transmitted through the dichroic mirror 67, and is reflected by the dichroic mirror 52. .. The light reflected by the dichroic mirror 52 passes through the objective lens 51 and is projected onto the fundus Ef. The liquid crystal panel 41 (or the liquid crystal panel 41 and the relay lens 42) can move in the optical axis direction.

(OCT optical system 8)
The OCT optical system 8 is an optical system for performing OCT measurement. The position of the focusing lens 87 is adjusted so that the end face of the optical fiber f1 is conjugated to the fundus Ef and the optical system based on the result of the reflex measurement performed before the OCT measurement.

The OCT optical system 8 is provided in an optical path whose wavelength is separated from the optical path of the reflex measurement optical system by a dichroic mirror 67. The optical path of the fixative projection system 4 is coupled to the optical path of the OCT optical system 8 by the dichroic mirror 83. Thereby, the optical axes of the OCT optical system 8 and the fixative projection system 4 can be coaxially coupled.

The OCT optical system 8 includes an OCT unit 100. As shown in FIG. 2, in the OCT unit 100, the OCT light source 101 is a wavelength sweep type (wavelength scanning type) light source capable of sweeping (scanning) the wavelength of emitted light, similar to a general swept source type OCT device. Consists of including. The wavelength sweep type light source is configured to include a laser light source including a resonator. The OCT light source 101 changes the output wavelength with time in a near-infrared wavelength band that cannot be visually recognized by the human eye.

As illustrated in FIG. 2, the OCT unit 100 is provided with an optical system for performing a swept source OCT. This optical system includes an interference optical system. This interference optical system has a function of dividing the light from the wavelength variable light source (wavelength sweep type light source) into the measurement light and the reference light, and the return light of the measurement light from the eye E to be inspected and the reference light via the reference light path. It has a function of generating interference light by superimposing the light sources and a function of detecting the interference light. The detection result (detection signal) of the interference light obtained by the interference optical system is a signal showing the spectrum of the interference light and is sent to the processing unit 9.

The OCT light source 101 includes, for example, a near-infrared wavelength tunable laser that changes the wavelength of emitted light (wavelength range of 1000 nm to 1100 nm) at high speed. The light L0 output from the OCT light source 101 is guided to the polarization controller 103 by the optical fiber 102, and its polarization state is adjusted. The light L0 whose polarization state has been adjusted is guided by the optical fiber 104 to the fiber coupler 105 and divided into the measurement light LS and the reference light LR.

The reference light LR is guided to the collimator 111 by the optical fiber 110, converted into a parallel light flux, passes through the optical path length correction member 112 and the dispersion compensation member 113, and is guided to the corner cube 114. The optical path length correction member 112 acts to match the optical path length of the reference light LR with the optical path length of the measured light LS. The dispersion compensating member 113 acts to match the dispersion characteristics between the reference light LR and the measurement light LS. The corner cube 114 is movable in the incident direction of the reference light LR, thereby changing the optical path length of the reference light LR.

The reference light LR via the corner cube 114 is converted from a parallel luminous flux to a focused luminous flux by the collimator 116 via the dispersion compensating member 113 and the optical path length correction member 112, and is incident on the optical fiber 117. The reference light LR incident on the optical fiber 117 is guided by the polarization controller 118 to adjust its polarization state, is guided to the attenuator 120 by the optical fiber 119 to adjust the amount of light, and is guided to the fiber coupler 122 by the optical fiber 121.

On the other hand, the measurement light LS generated by the fiber coupler 105 is guided by the optical fiber f1 and converted into a parallel light beam by the collimator lens unit 89, and is converted into a parallel light beam by the optical scanner 88, the focusing lens 87, the relay lenses 86 and 85, and the reflection mirror 84. It is reflected by the dichroic mirror 83 via the above.

The optical scanner 88 deflects the measurement light LS one-dimensionally or two-dimensionally. The optical scanner 88 includes, for example, a first galvano mirror and a second galvano mirror. The first galvano mirror deflects the measurement light LS so as to scan the fundus Ef in the horizontal direction orthogonal to the optical axis of the OCT optical system 8. The second galvano mirror deflects the measurement light LS deflected by the first galvano mirror so as to scan the fundus Ef in the direction perpendicular to the optical axis of the OCT optical system 8. Examples of the scanning mode of the measured optical LS by the optical scanner 88 include horizontal scan, vertical scan, cross scan, radial scan, circular scan, concentric circular scan, and spiral scan.

The measurement light LS reflected by the dichroic mirror 83 passes through the relay lens 82, is reflected by the reflection mirror 81, is transmitted through the dichroic mirror 67, is reflected by the dichroic mirror 52, is reflected by the objective lens 51, and is reflected by the objective lens 51. Incident to. The measurement light LS is scattered and reflected at various depth positions of the eye E to be inspected. The return light of the measurement light LS from the eye E to be inspected travels in the same direction as the outward path in the opposite direction, is guided to the fiber coupler 105, and reaches the fiber coupler 122 via the optical fiber 128.

The fiber coupler 122 combines (interferes with) the measurement light LS incident via the optical fiber 128 and the reference light LR incident via the optical fiber 121 to generate interference light. The fiber coupler 122 generates a pair of interference light LCs by branching the interference light at a predetermined branching ratio (for example, 1: 1). The pair of interference light LCs are guided to the detector 125 through the optical fibers 123 and 124, respectively.

The detector 125 is, for example, a balanced photodiode. The balanced photodiode includes a pair of photodetectors that detect each pair of interference light LCs, and outputs the difference between the pair of detection results obtained by these photodetectors. The detector 125 sends this output (detection signal) to the DAT (Data Acquisition System) 130.

A clock KC is supplied to the DAQ 130 from the OCT light source 101. The clock KC is generated in the OCT light source 101 in synchronization with the output timing of each wavelength swept within a predetermined wavelength range by the tunable light source. The OCT light source 101 optically delays one of the two branched lights obtained by branching the light L0 of each output wavelength, and then sets the clock KC based on the result of detecting these combined lights. Generate. The DAQ 130 samples the detection signal input from the detector 125 based on the clock KC. The DAQ 130 sends the sampling result of the detection signal from the detector 125 to the arithmetic processing unit 220 of the processing unit 9. The arithmetic processing unit 220 forms a reflection intensity profile in each A line by, for example, performing a Fourier transform or the like on the spectral distribution based on the sampling data for each series of wavelength scans (for each A line). Further, the arithmetic processing unit 220 forms image data by imaging the reflection intensity profile of each A line.

In this example, the corner cube 114 for changing the length of the optical path (reference optical path, reference arm) of the reference optical path LR is provided, but the measured optical path length and the reference optical path length are provided by using an optical member other than these. It is also possible to change the difference with.

The processing unit 9 calculates a refractive power value from the measurement result obtained by using the reflex measurement optical system, and based on the calculated refractive power value, the fundus Ef, the reflex measurement light source 61, and the image pickup element 59 are coupled. The refraction measurement light source 61 and the focusing lens 74 are moved to the respective positions in the optical axis direction. In some embodiments, the processing unit 9 moves the liquid crystal panel 41 in the optical axis direction in conjunction with the movement of the reflex measurement light source 61 and the focusing lens 74. In some embodiments, the processing unit 9 moves the focusing lens 87 of the OCT optical system 8 in the optical axis direction in conjunction with the movement of the focusing lens 74.

As described above, the OCT optical system 8 is provided in the optical path whose wavelength is separated from the optical path of the reflex measurement optical system by the dichroic mirror 67. That is, the inspection optical system provided in the optical path wavelength-separated from the optical path of the reflex measurement optical system by the dichroic mirror 67 includes an interference optical system. The interference optical system divides the light in a predetermined wavelength range from the light source into the reference light and the measurement light, projects the measurement light onto the test eye, and interferes with the return light of the measurement light from the test eye and the reference light. Is detected.

For example, when the optical path of the OCT optical system 8 is separated from the optical path of the reflex measurement optical system using a perforated prism, the optical system is configured so that the measurement light is passed through the hole formed in the perforated prism. , It is necessary to consider the eclipse of the measurement light and its return light. On the other hand, by performing wavelength separation with the dichroic mirror 67, it is possible to increase the amount of light used in each optical system as compared with the case of using a perforated prism.

By the way, the transmission characteristic (reflection characteristic) of the dichroic mirror 52 changes according to the angle of incidence of light on the optical path composite surface. For example, when the dichroic mirror 52 is composed of a dielectric multilayer film filter, the transmission characteristics change as described above.

FIG. 3 schematically shows changes in the transmission characteristics of the dichroic mirror 52. In FIG. 3, the vertical axis represents the transmittance and the horizontal axis represents the wavelength of the incident light.

As shown in FIG. 3, when the transmission characteristics of a plurality of lights having different incident angles with respect to the optical path composite surface change, the cut-on wavelength (cut-off wavelength) changes according to the incident angle.

When the anterior segment observation system 5 is a telecentric optical system and the light refracted by the objective lens 51 is incident on the optical path synthesis surface of the dichroic mirror 52, the light is incident within a predetermined range on the optical path synthesis surface. Therefore, it means that the incident angle of light changes within a predetermined range. For example, the incident angle of the light incident on the optical path synthesis surface near the optical axis of the objective lens 51 and the incident angle of the light incident on the position off the optical axis are different. That is, the transmission characteristics of the light incident on the position near the optical axis and the transmission characteristics of the light incident on the position off the optical axis are different.

4A and 4B schematically show the light incident on the optical path synthesis surface of the dichroic mirror 52. 4A and 4B show the incident angle with respect to the incident position on the dichroic mirror 52 by the OCT optical system 8 and the anterior eye observation system 5, respectively, and are an enlarged view of a part of the optical system of FIG. In FIGS. 4A and 4B, the same parts as those in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

For example, light incident from below the optical axis of the objective lens 51, such as the incident light IL1 in FIG. 4A and the incident light IL2 in FIG. 4B, has a large incident angle with respect to the normal of the optical path synthesis surface. In this case, the transmission center wavelength of the light shifts to the shorter wavelength side with respect to the transmission center wavelength (reference transmission center wavelength) in the optical axis.

For example, light incident from above the optical axis of the objective lens 51, such as the incident light IL11 in FIG. 4A and the incident light IL12 in FIG. 4B, has a smaller incident angle with respect to the normal of the optical path synthesis surface. In this case, the transmission center wavelength of the light shifts to the longer wavelength side with respect to the transmission center wavelength in the optical axis. As described above, the incident angles of the OCT optical system 8 and the anterior eye observation system 5 with respect to the incident position on the dichroic mirror 52 are different, and it is not possible to form an optical film that optimizes the transmittance for both optical systems. ..

As described above, the transmission characteristics (transmission center wavelength) differ depending on the incident position of light on the optical path synthesis surface of the dichroic mirror 52. The incident angle dependence of the transmission characteristic of the dichroic mirror 52 causes, for example, a decrease in the transmittance of the light returning to the anterior eye portion observation system 5 in a predetermined incident angle range.

FIG. 5 shows an explanatory diagram of the incident angle dependence of the return light to the anterior eye observation system 5. In FIG. 5, the vertical axis represents the transmittance and the horizontal axis represents the wavelength.

For example, when the anterior segment illumination light source 50 illuminates the anterior segment with illumination light ILZ having a single wavelength λ1, the transmission characteristic of the incident light IL1 on the lower side of the optical axis is relative to the optical path synthesis surface of the dichroic mirror 52. It becomes like T1 to T1'depending on the incident angle. Similarly, the transmission characteristic of the incident light IL11 on the upper side of the optical axis becomes T11 to T11'depending on the incident angle with respect to the optical path synthesis surface. The transmission characteristic T0'indicates the transmission characteristic of the incident light on the optical axis. That is, the wavelength distribution of the transmittance of the return light deviates from the wavelength distribution of the transmittance of the illumination light ILZ from the anterior segment illumination light source 50 according to the incident angle with respect to the optical path synthesis surface of the dichroic mirror 52. Therefore, the anterior-eye observation system 5 detects the light transmitted by the lower side and the upper side of the optical axis with different transmission characteristics with respect to the return light of the illumination light ILZ, and a part of the light is darkened. , The image quality of the acquired anterior eye image deteriorates.

The anterior segment illumination light source 50 according to some embodiments illuminates the anterior segment with illumination light in a wavelength range including a transmission center wavelength corresponding to the incident angle of the return light of the illumination light with respect to the optical path composite surface of the dichroic mirror 52. do. For example, the anterior segment illumination light source 50 has a transmission center whose wavelength is shifted by a shift corresponding to the incident angle with respect to the reference transmission center wavelength λ0 based on the light transmission characteristic of the reference incident angle on the optical path synthesis surface of the dichroic mirror 52. The anterior segment is illuminated with illumination light in the wavelength range including the peak wavelength corresponding to the wavelength λs. The reference incident angle is, for example, the incident angle of light incident on the position of the optical axis of the objective lens 51 on the optical path synthesis surface. In some embodiments, the peak wavelength is the same as the transmission center wavelength λs. In some embodiments, the peak wavelength is the peak wavelength of a light source that outputs light in a wavelength range including the transmission center wavelength λs among a plurality of light sources. As a result, by compensating for the amount of light transmitted by the lower side and the upper side of the optical axis of the objective lens 51 with different transmission characteristics, it is possible to obtain a uniformly bright front eye image. Become.

Further, the incident angle dependence of the dichroic mirror 52 also causes a decrease in the transmittance of light in a predetermined incident angle range for the return light to the reflex measurement optical system and the OCT optical system 8. As a result, the accuracy of measurement and OCT measurement is lowered. In this case, by changing the wavelength of the illumination light as described above and using the inclined film formed on the optical path synthesis surface of the dichroic mirror 52 in combination, the light having the optimum wavelength range for both optical systems is separated by wavelength. Will be possible.

The dichroic mirror 52 according to some embodiments is a gradient film filter. That is, on the dichroic mirror 52 according to some embodiments, an optical film is formed so that the film thickness changes according to the position of the incident end surface of light on the optical path synthesis surface. By forming the optical film so that the film thickness is inclined, it is possible to compensate for the dependence of the dichroic mirror 52 on the incident angle with respect to the optical path composite surface.

Since the incident angle of the return light of the measured light LS and the incident angle of the return light of the anterior segment observation system 5 on the optical path composite surface of the dichroic mirror 52 are different, the incident angle dependence of both return lights can be determined only by the gradient film filter. It cannot be compensated. For example, when an inclined film is formed on the optical path synthesis surface of the dichroic mirror 52 so as to compensate for the incident angle dependence of the return light of the measurement light LS of the OCT optical system 8, the front eye portion observation system 5 having a close wavelength range is formed. The transmittance of the return light is affected, and the transmittance of light in a predetermined incident angle range is reduced.

Therefore, in this embodiment, by forming an inclined film on the optical path synthesis surface of the dichroic mirror 52, the dependence of the incident angle on the return light of the measurement light LS of the OCT optical system 8 is compensated. Further, the anterior segment illumination light source 50 illuminates the anterior segment with illumination light in a wavelength range including the transmission center wavelength corresponding to the incident angle of the return light of the illumination light with respect to the optical path synthesis surface of the dichroic mirror 52. It compensates for the angle of incidence dependence on the return light to the ocular observation system 5.

FIG. 6 shows an explanatory diagram of the frontal eye illumination light source 50 according to the embodiment. FIG. 6 is an enlarged view of a part of the optical system of FIG. In FIG. 6, the same parts as those in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

When the return light to the anterior eye portion observation system 5 on the optical path composite surface of the dichroic mirror 52 is incident on a predetermined range, the incident angle of the return light on the optical path composite surface changes within a predetermined range. A predetermined range of the incident angle of the return light is specified by the upper end UP and the lower end LW.

It is assumed that the optical path synthesis surface of the dichroic mirror 52 is tilted at an angle D0 with respect to the optical axis of the objective lens 51. The range of the incident angle of the return light to the anterior eye observation system 5 on the optical path synthesis surface is represented by D0 ± d. The transmission center wavelength (first transmission center wavelength) at the upper end UP (angle D0 + d) is shifted by the shift corresponding to the upper end UP with respect to the reference transmission center wavelength λ0 based on the light transmission characteristics of the reference incident angle on the optical path synthesis surface. It is the wavelength that was set. Similarly, the transmission center wavelength (second transmission center wavelength) at the lower end LW (angle D0−d) corresponds to the lower end LW with respect to the reference transmission center wavelength λ0 based on the light transmission characteristics of the reference incident angle on the optical path synthesis surface. The wavelength is shifted by the amount of shift.

The anterior segment illumination light source 50 has a first peak wavelength λp1 corresponding to the transmission center wavelength (first transmission center wavelength) at the upper end UP and a second peak corresponding to the transmission center wavelength (second transmission center wavelength) at the lower end LW. The anterior segment is illuminated with illumination light in a wavelength range including the wavelength λp2. In some embodiments, the first peak wavelength λp1 is the same wavelength as the first transmission center wavelength. In some embodiments, the first peak wavelength λp1 is the peak wavelength of a light source that outputs light in a wavelength range including the first transmission center wavelength among a plurality of light sources. In some embodiments, the second peak wavelength λp2 is the same wavelength as the second transmission center wavelength. In some embodiments, the second peak wavelength λp2 is the peak wavelength of the light source that outputs light in the wavelength range including the second transmission center wavelength among the plurality of light sources.

In some embodiments, the anterior eye illumination light source 50 includes a first illumination light source 50A and a second illumination light source 50B. The first illumination light source 50A irradiates the illumination light in the wavelength range including the first peak wavelength λp1. The second illumination light source 50B irradiates the illumination light in the wavelength range including the second peak wavelength λp2.

In some embodiments, the anterior eye illumination light source 50 is composed of a single light source that emits illumination light in a wavelength range including a first peak wavelength λp1 and a second peak wavelength λp2. In some embodiments, the anterior eye illumination light source 50 comprises three or more light sources that emit illumination light in a wavelength range including a first peak wavelength λp1 and a second peak wavelength λp2.

7A and 7B show explanatory views of the first illumination light source 50A and the second illumination light source 50B. FIG. 7A schematically shows the light source characteristics of the first illumination light source 50A. FIG. 7B schematically shows the light source characteristics of the second illumination light source 50B. In FIGS. 7A and 7B, the vertical axis represents the transmittance and the horizontal axis represents the wavelength.

As shown in FIG. 7A, the first illumination light source 50A emits illumination light IL20 in a wavelength range including the first peak wavelength λp1 shifted to the long wavelength side with respect to the reference transmission center wavelength λ0. As shown in FIG. 7B, the second illumination light source 50B emits illumination light IL21 in a wavelength range including the second peak wavelength λp2 shifted to the short wavelength side with respect to the reference transmission center wavelength λ0.

The first overlapping range between the light source characteristic of the illumination light IL20 in FIG. 7A and the light transmission characteristic T20 of the upper end UP of the range of the incident light on the optical path synthesis surface is with respect to the optical axis detected in the anterior segment observation system 5. Corresponds to the amount of return light above. Similarly, the second overlapping range between the light source characteristic of the illumination light IL21 in FIG. 7B and the light transmission characteristic T21 of the lower end LW of the range of the incident light on the optical path synthesis surface is the light detected by the anterior segment observation system 5. Corresponds to the amount of return light below the axis. By setting the first peak wavelength λp1 and the second peak wavelength λp2 so that the first overlapping range and the second overlapping range have the same area, it is possible to make the brightness of the acquired frontal eye image uniform. can.

<Processing system configuration>
The configuration of the processing system of the ophthalmic apparatus 1000 will be described. FIG. 8 shows an example of the functional configuration of the processing system of the ophthalmic apparatus 1000. FIG. 8 shows an example of a functional block diagram of the processing system of the ophthalmic apparatus 1000.

The processing unit 9 controls each unit of the ophthalmic apparatus 1000. Further, the processing unit 9 can execute various arithmetic processes. The processing unit 9 includes a processor. The functions of the processor are, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), a programmable logic device (for example, a SPLD (Simple Program)). , FPGA (Field Programmable Gate Array)) and the like. The processing unit 9 realizes the function according to the embodiment by reading and executing, for example, a program stored in a storage circuit or a storage device.

The processing unit 9 includes a control unit 210 and an arithmetic processing unit 220. Further, the ophthalmic apparatus 1000 includes a moving mechanism 200, a display unit 270, an operation unit 280, and a communication unit 290.

The moving mechanism 200 includes a Z alignment system 1, an XY alignment system 2, a kerato measurement system 3, a fixative projection system 4, an anterior eye observation system 5, a reflex measurement projection system 6, a reflex measurement light receiving system 7, an OCT optical system 8, and the like. It is a mechanism for moving the head portion in which the optical system of the above is housed in the front-back and left-right directions. For example, the moving mechanism 200 is provided with an actuator that generates a driving force for moving the head portion and a transmission mechanism that transmits the driving force. The actuator is composed of, for example, a pulse motor. The transmission mechanism is composed of, for example, a combination of gears or a rack and pinion. The control unit 210 (main control unit 211) controls the moving mechanism 200 by sending a control signal to the actuator.

(Control unit 210)
The control unit 210 includes a processor and controls each unit of the ophthalmologic device. The control unit 210 includes a main control unit 211 and a storage unit 212. A computer program for controlling the ophthalmologic device is stored in the storage unit 212 in advance. The computer program includes a light source control program, a detector control program, an optical scanner control program, an optical system control program, an arithmetic processing program, a user interface program, and the like. When the main control unit 211 operates according to such a computer program, the control unit 210 executes the control process.

The main control unit 211 performs various controls of the ophthalmic apparatus as a measurement control unit. The control for the Z alignment system 1 includes the control of the Z alignment light source 11 and the control of the line sensor 13. The control of the Z alignment light source 11 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. The control of the line sensor 13 includes exposure adjustment, gain adjustment, detection rate adjustment, and the like of the detection element. As a result, the Z alignment light source 11 is switched between lighting and non-lighting, and the amount of light is changed. The main control unit 211 captures the signal detected by the line sensor 13, and determines the projection position of the light with respect to the line sensor 13 based on the captured signal. The main control unit 211 obtains the position of the corneal apex of the eye E to be inspected based on the specified projection position, and controls the movement mechanism 200 based on this to move the head unit in the front-rear direction (Z alignment).

The control for the XY alignment system 2 includes the control of the XY alignment light source 21 and the like. The control of the XY alignment light source 21 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. As a result, the XY alignment light source 21 is switched between lighting and non-lighting, and the amount of light is changed. The main control unit 211 captures the signal detected by the image pickup device 59, and determines the position of the bright spot image based on the return light of the light from the XY alignment light source 21 based on the captured signal. The main control unit 211 controls the movement mechanism 200 so that the displacement from the position of the bright spot image Br with respect to a predetermined target position (for example, the center position of the alignment mark AL) is canceled, and moves the head unit in the left-right / up-down direction. Move (XY alignment).

The control for the kerato measurement system 3 includes the control of the keratling light source 32 and the like. The control of the keratling light source 32 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. As a result, the lighting and non-lighting of the keratling light source 32 are switched, and the amount of light is changed. The main control unit 211 causes the arithmetic processing unit 220 to perform a known calculation on the keratling image detected by the image sensor 59. As a result, the corneal shape parameter of the eye E to be inspected is obtained.

The control for the fixative projection system 4 includes the control of the liquid crystal panel 41 and the like. The control of the liquid crystal panel 41 includes turning on / off the display of the fixative and switching the display position of the fixative. As a result, the fixative is projected onto the fundus Ef of the eye E to be inspected. For example, the fixative projection system 4 includes a moving mechanism that moves the liquid crystal panel 41 (or the liquid crystal panel 41 and the relay lens 42) in the optical axis direction. Similar to the moving mechanism 200, the moving mechanism is provided with an actuator that generates a driving force for moving the moving mechanism and a transmission mechanism that transmits the driving force. The main control unit 211 controls the moving mechanism by sending a control signal to the actuator, and at least moves the liquid crystal panel 41 in the optical axis direction. As a result, the position of the liquid crystal panel 41 is adjusted so that the liquid crystal panel 41 and the fundus Ef are optically conjugated.

The control for the anterior eye portion observation system 5 includes the control of the anterior eye portion illumination light source 50, the control of the image pickup element 59, and the like. The control of the anterior eye illumination light source 50 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. As a result, the lighting and non-lighting of the frontal eye illumination light source 50 (first illumination light source 50A, second illumination light source 50B) is switched, and the amount of light is changed. The main control unit 211A can control lighting, extinguishing, light amount adjustment, aperture adjustment, and the like with respect to only one of the first illumination light source 50A and the second illumination light source 50B. The control of the image pickup element 59 includes exposure adjustment, gain adjustment, detection rate adjustment, and the like of the image pickup element 59. The main control unit 211 captures the signal detected by the image pickup device 59, and causes the arithmetic processing unit 220 to perform processing such as forming an image based on the captured signal.

The control for the reflex measurement projection system 6 includes the control of the reflex measurement light source 61, the control of the rotary prism 66, and the like. The control of the reflex measurement light source 61 includes turning on / off the light source, adjusting the amount of light, adjusting the aperture, and the like. As a result, the lighting of the reflex measurement light source 61 can be switched between lighting and non-lighting, and the amount of light can be changed. For example, the reflex measurement projection system 6 includes a moving mechanism that moves the reflex measurement light source 61 in the optical axis direction. Similar to the moving mechanism 200, the moving mechanism is provided with an actuator that generates a driving force for moving the moving mechanism and a transmission mechanism that transmits the driving force. The main control unit 211 controls the movement mechanism by sending a control signal to the actuator, and moves the reflex measurement light source 61 in the optical axis direction. Control of the rotary prism 66 includes rotation control of the rotary prism 66 and the like. For example, a rotation mechanism for rotating the rotary prism 66 is provided, and the main control unit 211 rotates the rotary prism 66 by controlling this rotation mechanism.

The control for the reflex measurement light receiving system 7 includes the control of the focusing lens 74 and the like. Control of the focusing lens 74 includes control of movement of the focusing lens 74 in the optical axis direction. For example, the reflex measurement light receiving system 7 includes a moving mechanism that moves the focusing lens 74 in the optical axis direction. Similar to the moving mechanism 200, the moving mechanism is provided with an actuator that generates a driving force for moving the moving mechanism and a transmission mechanism that transmits the driving force. The main control unit 211 controls the moving mechanism by sending a control signal to the actuator, and moves the focusing lens 74 in the optical axis direction. The main control unit 211 illuminates the reflex measurement light source 61 and the focusing lens 74, for example, according to the refractive power of the eye E to be inspected so that the reflex measurement light source 61, the fundus Ef, and the image pickup element 59 are optically coupled. It can be moved in the axial direction.

The control for the OCT optical system 8 includes the control of the OCT light source 101, the control of the optical scanner 88, the control of the focusing lens 87, the control of the corner cube 114, the control of the detector 125, the control of the DAQ 130, and the like. The control of the OCT light source 101 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. The control of the optical scanner 88 includes control of the scanning position, scanning range and scanning speed by the first galvano mirror, control of the scanning position, scanning range and scanning speed by the second galvano mirror and the like. Control of the focusing lens 87 includes control of movement of the focusing lens 87 in the optical axis direction. For example, the OCT optical system 8 includes a moving mechanism that moves the focusing lens 87 in the optical axis direction. Similar to the moving mechanism 200, the moving mechanism is provided with an actuator that generates a driving force for moving the moving mechanism and a transmission mechanism that transmits the driving force. The main control unit 211 controls the moving mechanism by sending a control signal to the actuator, and moves the focusing lens 87 in the optical axis direction. For example, the main control unit 211 may move the focusing lens 87 in conjunction with the movement of the focusing lens 74, and then move only the focusing lens 87 based on the intensity of the interference signal. The control of the corner cube 114 includes movement control along the optical path of the corner cube 114. For example, the OCT optical system 8 includes a moving mechanism that moves the corner cube 114 in a direction along an optical path. Similar to the moving mechanism 200, the moving mechanism is provided with an actuator that generates a driving force for moving the moving mechanism and a transmission mechanism that transmits the driving force. The main control unit 211 controls the moving mechanism by sending a control signal to the actuator, and moves the corner cube 114 in the direction along the optical path. The control of the detector 125 includes exposure adjustment, gain adjustment, detection rate adjustment, and the like of the detection element. The main control unit 211 samples the signal detected by the detector 125 by the DAQ 130, and causes the arithmetic processing unit 220 (image forming unit 222) to perform processing such as image formation based on the sampled signal.

Further, the main control unit 211 performs a process of writing data to the storage unit 212 and a process of reading data from the storage unit 212.

(Memory unit 212)
The storage unit 212 stores various data. The data stored in the storage unit 212 includes, for example, measurement results of objective measurement, image data of tomographic images, image data of fundus images, eye information to be inspected, and the like. The eye test information includes information about the subject such as the patient ID and name, and information about the test eye such as left eye / right eye identification information. Further, various programs and data for operating the ophthalmic apparatus are stored in the storage unit 212.

(Arithmetic processing unit 220)
The arithmetic processing unit 220 includes an eye refractive power calculation unit 221, an image forming unit 222, and a data processing unit 223.

The eye refractive power calculation unit 221 receives a ring image (pattern image) obtained by receiving the return light of the ring-shaped luminous flux (ring-shaped measurement pattern) projected on the fundus Ef by the reflex measurement projection system 6 by the image pickup element 59. ) Is analyzed. For example, the optical power calculation unit 221 obtains the position of the center of gravity of the ring image from the brightness distribution in the image in which the obtained ring image is drawn, and obtains the brightness distribution along a plurality of scanning directions radially extending from the position of the center of gravity. , The ring image is specified from this brightness distribution. Subsequently, the optical power calculation unit 221 obtains an approximate ellipse of the specified ring image, and substitutes the major axis and the minor axis of the approximate ellipse into a known equation to obtain the spherical power, the astigmatic power, and the astigmatic axis angle. .. Alternatively, the eye refractive power calculation unit 221 can obtain the parameter of the eye refractive power based on the deformation and displacement of the ring image with respect to the reference pattern.

Further, the eye refractive power calculation unit 221 calculates the corneal refractive power, the corneal astigmatism degree, and the corneal astigmatism axis angle based on the keratling image acquired by the anterior eye portion observation system 5. For example, the optical power calculation unit 221 calculates the radius of curvature of the cornea of the strong main meridian and the weak main meridian on the anterior surface of the cornea by analyzing the keratling image, and calculates the above parameter based on the radius of curvature of the cornea.

The image forming unit 222 forms the image data of the tomographic image of the fundus Ef based on the signal detected by the detector 115. That is, the image forming unit 222 forms the image data of the eye E to be inspected based on the detection result of the interference light LC by the interference optical system. This process includes processing such as filtering and FFT (Fast Fourier Transform), as in the case of the conventional spectral domain type OCT. The image data acquired in this way is a data set containing a group of image data formed by imaging a reflection intensity profile in a plurality of A lines (paths of each measured light LS in the eye E to be inspected). be.

In order to improve the image quality, it is possible to superimpose (add and average) a plurality of data sets collected by repeating scanning with the same pattern multiple times.

The data processing unit 223 performs various data processing (image processing) and analysis processing on the tomographic image formed by the image forming unit 222. For example, the data processing unit 223 executes correction processing such as image brightness correction and dispersion correction. Further, the data processing unit 223 performs various image processing and analysis processing on the image (anterior eye portion image and the like) obtained by using the anterior eye portion observation system 5.

The data processing unit 223 can form volume data (voxel data) of the eye E to be inspected by executing known image processing such as interpolation processing for interpolating pixels between tomographic images. When displaying an image based on volume data, the data processing unit 223 performs rendering processing on the volume data to form a pseudo three-dimensional image when viewed from a specific line-of-sight direction.

(Display unit 270, operation unit 280)
The display unit 270, as a user interface unit, displays information under the control of the control unit 210. The display unit 270 includes the display unit 10 shown in FIG. 1 and the like.

The operation unit 280 is used as a user interface unit to operate the ophthalmologic device. The operation unit 280 includes various hardware keys (joysticks, buttons, switches, etc.) provided in the ophthalmic apparatus. Further, the operation unit 280 may include various software keys (buttons, icons, menus, etc.) displayed on the touch panel type display screen 10a.

At least a part of the display unit 270 and the operation unit 280 may be integrally configured. As a typical example thereof, there is a touch panel type display screen 10a.

(Communication unit 290)
The communication unit 290 has a function for communicating with an external device (not shown). The communication unit 290 includes a communication interface according to the connection form with the external device. An example of an external device is a spectacle lens measuring device for measuring the optical characteristics of a lens. The spectacle lens measuring device measures the power of the spectacle lens worn by the subject, and inputs this measurement data to the ophthalmologic device 1000. Further, the external device may be an arbitrary ophthalmic device, a device (reader) for reading information from a recording medium, a device (writer) for writing information on a recording medium, or the like. Further, the external device may be a hospital information system (HIS) server, a DICOM (Digital Imaging and Communication in Medicine) server, a doctor terminal, a mobile terminal, a personal terminal, a cloud server, or the like. The communication unit 290 may be provided in, for example, the processing unit 9.

The reflex measurement optical system or the OCT optical system 8 is an example of the “inspection optical system” according to the embodiment. The dichroic mirror 52 is an example of the "optical path synthesis member" according to the embodiment. The anterior eye illumination light source 50 is an example of the “anterior eye illumination system” according to the embodiment. The optical system included in the OCT unit 100 is an example of the “interference optical system” according to the embodiment.

<Operation example>
The operation of the ophthalmic apparatus 1000 according to the embodiment will be described.

FIG. 9 shows an example of the operation of the ophthalmic apparatus 1000. FIG. 9 shows a flow chart of an operation example of the ophthalmic apparatus 1000.

(S1: Alignment)
The ophthalmic apparatus 1000 performs alignment when the examiner performs a predetermined operation on the operation unit 280 with the subject's face fixed to the face receiving portion (not shown).

Specifically, the main control unit 211 turns on the Z alignment light source 11 and the XY alignment light source 21. Further, the main control unit 211 turns on the front eye portion illumination light source 50. As a result, the anterior segment of the eye E to be inspected is illuminated by the first illumination light source 50A and the second illumination light source 50B. The processing unit 9 acquires an image pickup signal of the front eye portion image on the image pickup surface of the image pickup element 59, and causes the display unit 270 to display the front eye portion image. After that, the optical system shown in FIG. 1 is moved to the inspection position of the eye E to be inspected. The examination position is a position where the examination of the eye E to be inspected can be performed within sufficient accuracy. The eye E to be inspected is placed at the examination position via the above-mentioned alignment (alignment by the Z alignment system 1 and the XY alignment system 2 and the anterior eye observation system 5). The movement of the optical system is executed by the control unit 210 according to an operation or instruction by the user or an instruction by the control unit 210. That is, the movement of the optical system to the examination position of the eye E to be inspected and the preparation for performing the objective measurement are performed.

Further, the main control unit 211 moves the reflex measurement light source 61, the focusing lens 74, and the liquid crystal panel 41 to the position of the origin (for example, the position corresponding to 0D) along the respective optical axes.

(S2: Fixation control)
In step S2, the main control unit 211 causes the liquid crystal panel 41 to display a pattern indicating the fixative at a display position corresponding to a desired fixative position. As a result, the eye E to be inspected is gazed at a desired fixative position.

Following the fixative control in step S2, the ophthalmologic apparatus 1000 may perform kerato measurement. In this case, the main control unit 211 turns on the keratling light source 32. When light is output from the keratling light source 32, a ring-shaped light flux for measuring the shape of the cornea is projected onto the cornea Cr of the eye E to be inspected. The ocular refractive power calculation unit 221 calculates the corneal radius of curvature by performing arithmetic processing on the image acquired by the image pickup element 59, and the corneal refractive power, corneal astigmatism, and corneal astigmatism are calculated from the calculated corneal radius of curvature. Calculate the axis angle. In the control unit 210, the calculated corneal refractive power and the like are stored in the storage unit 212. The operation of the ophthalmic apparatus 1000 shifts to step S3 by the instruction from the main control unit 211 or the user's operation or instruction to the operation unit 280.

(S3: Objective measurement)
Next, the main control unit 211 projects the fixative on the eye E to be inspected by controlling the liquid crystal panel 41, and causes the reflex measurement to be executed.

In the reflex measurement, the main control unit 211 projects a ring-shaped measurement pattern luminous flux for the reflex measurement onto the eye E to be inspected as described above. A ring image based on the return light of the measurement pattern luminous flux from the eye E to be inspected is formed on the image pickup surface of the image pickup element 59. The main control unit 211 determines whether or not a ring image based on the return light from the fundus Ef detected by the image sensor 59 could be acquired. For example, the main control unit 211 detects the position (pixel) of the edge of the image based on the return light detected by the image sensor 59, and whether the width of the image (difference between the outer diameter and the inner diameter) is equal to or more than a predetermined value. Judge whether or not. Alternatively, the main control unit 211 determines whether or not a ring image can be acquired by determining whether or not a ring can be formed based on a point (image) having a predetermined height (ring diameter) or more. May be good.

When it is determined that the ring image can be obtained, the optical power calculation unit 221 analyzes the ring image based on the return light of the measurement pattern luminous flux projected on the eye E to be inspected by a known method, and analyzes the provisional spherical power S and the tentative spherical power S. A tentative astigmatic power C is obtained. Based on the obtained temporary spherical power S and astigmatic power C, the main control unit 211 positions the reflex measurement light source 61, the focusing lens 74, and the liquid crystal panel 41 at the equivalent spherical power (S + C / 2) position (temporary distance). Move to the position corresponding to the point). The main control unit 211 further moves the liquid crystal panel 41 from that position to the cloud fog position, and then controls the reflex measurement projection system 6 and the reflex measurement light receiving system 7 as the main measurement to acquire the ring image again. The main control unit 211 causes the eye refractive power calculation unit 221 to calculate the spherical power, the astigmatic power, and the astigmatic axis angle from the analysis result of the ring image obtained in the same manner as described above and the movement amount of the focusing lens 74.

Further, the eye refractive power calculation unit 221 obtains a position corresponding to the far point of the eye E to be inspected (a position corresponding to the far point obtained by this measurement) from the obtained spherical power and astigmatic power. The main control unit 211 moves the liquid crystal panel 41 to a position corresponding to the obtained far point. In the control unit 210, the position of the focusing lens 74, the calculated spherical power, and the like are stored in the storage unit 212. The operation of the ophthalmic apparatus 1000 shifts to step S4 by the instruction from the main control unit 211 or the user's operation or instruction to the operation unit 280.

When it is determined that the ring image cannot be acquired, the main control unit 211 considers the possibility of an intensified refractive error eye and sets the reflex measurement light source 61 and the focusing lens 74 on the minus power side (for example, in a preset step). -10D), move to the plus frequency side (for example, + 10D). The main control unit 211 detects the ring image at each position by controlling the reflex measurement light receiving system 7. When it is determined that the ring image cannot be acquired even after that, the main control unit 211 executes a predetermined measurement error process. At this time, the operation of the ophthalmic apparatus 1000 may shift to step S4. In the control unit 210, information indicating that the reflex measurement result was not obtained is stored in the storage unit 212.

As described above, the focusing lens 87 of the OCT optical system 8 is moved in the optical axis direction in conjunction with the movement of the reflex measuring light source 61 and the focusing lens 74.

(S4: tomographic image photography)
In step S4, the main control unit 211 projects the fixative on the eye E to be inspected by controlling the liquid crystal panel 41, and causes the OCT measurement to be executed.

The main control unit 211 turns on the OCT light source 101 and controls the optical scanner 88 to scan a predetermined portion of the fundus Ef with the measurement light LS. The detection signal obtained by scanning the measurement light LS is sent to the image forming unit 222. The image forming unit 222 forms a tomographic image of the fundus Ef from the obtained detection signal. This completes the operation of the ophthalmic apparatus 1000 (end).

[Action / Effect]
The operation and effect of the ophthalmic appliance according to the embodiment will be described.

The ophthalmic apparatus (1000) according to some embodiments includes an objective lens (51), an anterior ocular segment observation system (5), an inspection optical system (OCT optical system 8 or a ref measurement optical system), and an optical path synthesis member. (Dycroic mirror 52) and an anterior segment illumination system (anterior segment illumination light source 50). The anterior eye portion observation system detects the first return light of the illumination light from the anterior segment of the eye to be inspected (E) via the objective lens. The inspection optical system projects light onto the eye to be inspected through the objective lens and detects the second return light from the eye to be inspected. The optical path synthesis member synthesizes the optical path of the inspection optical system and the optical path of the anterior segment observation system on the optical path synthesis surface arranged at an angle with respect to the optical axis of the objective lens. The anterior segment illumination system illuminates the anterior segment with illumination light in a wavelength range including a wavelength corresponding to the incident angle of the first return light with respect to the optical path composite surface.

According to such a configuration, illumination in a wavelength range including a wavelength corresponding to the incident angle of the first return light to the optical path synthesis surface of the optical path synthesis member that synthesizes the optical path of the inspection optical system and the optical path of the front eye observation system. Since the anterior segment is illuminated with light, the decrease in the amount of light to the anterior segment observation system due to the wavelength shift due to the dependence of the incident angle on the optical path synthesis surface is compensated, and the image quality of the anterior segment observation image is improved. Will be possible.

In the ophthalmic apparatus according to some embodiments, in the anterior ocular segment illumination system, the wavelength is shifted by the shift corresponding to the incident angle with respect to the reference transmission center wavelength (λ0) based on the light transmission characteristics on the optical path synthesis surface. The anterior segment of the eye is illuminated with illumination light in a wavelength range including peak wavelengths (λp1, λp2) corresponding to the transmission center wavelength (first transmission center wavelength, second transmission center wavelength).

According to such a configuration, it corresponds to the transmission center wavelength whose wavelength is shifted by the shift corresponding to the incident angle of the first return light with respect to the reference transmission center wavelength specified from the transmission characteristics with respect to the incident angle on the optical path synthesis surface. Since the anterior segment is illuminated with illumination light in the wavelength range including the peak wavelength, the decrease in the amount of light to the anterior segment observation system due to the wavelength shift due to the incident angle dependence on the optical path synthesis surface is compensated with high accuracy. can do.

In the ophthalmic apparatus according to some embodiments, the optical path composite surface has an optical film such that the film thickness changes according to the position of the incident end surface of the light so as to compensate for the incident angle dependence of the second return light. It is formed.

According to such a configuration, even when an inclined film is formed on the optical path composite surface, the illumination light in the wavelength range including the peak wavelength corresponding to the incident angle of the first return light on the optical path composite surface is used. Since the eye area is illuminated, the decrease in the amount of light to the anterior segment observation system due to the wavelength shift due to the dependence of the incident angle on the optical path synthesis surface is compensated for while compensating for the decrease in the amount of light to the inspection optical system. It is possible to improve the image quality of the part observation image.

In the ophthalmic apparatus according to some embodiments, the optical path composite surface has an optical film such that the film thickness changes according to the position of the incident end surface of the light so as to compensate for the incident angle dependence of the second return light. It is formed. In the anterior segment illumination system, the wavelength is increased by the shift corresponding to the upper end (UP) of the incident angle of the first return light with respect to the optical path composite surface with respect to the reference transmission center wavelength (λ0) based on the light transmission characteristics on the optical path composite surface. The first peak wavelength (λp1) corresponding to the shifted first transmission center wavelength and the second transmission center whose wavelength is shifted by the shift corresponding to the lower end (LW) of the incident angle with respect to the optical path synthesis surface with respect to the reference transmission center wavelength. The anterior segment of the eye is illuminated with illumination light in a wavelength range including the second peak wavelength (λp2) corresponding to the wavelength.

According to such a configuration, even when an inclined film is formed on the optical path composite surface to compensate for the incident angle dependence of the second return light, the incident angle of the first return light on the optical path composite surface is formed. Since the anterior segment of the eye is illuminated with the illumination light in the wavelength range including the peak wavelength corresponding to the upper end and the lower end of the range, the incident angle dependence on the optical path synthesis surface is made while compensating for the decrease in the amount of light to the inspection optical system. It is possible to compensate for the decrease in the amount of light to the anterior segment observation system due to the resulting wavelength shift.

In the ophthalmic apparatus according to some embodiments, the inspection optical system divides the light from the light source (OCT light source 101) into the reference light (LR) and the measurement light (LS), and passes the light to the subject through the objective lens. It includes an interference optical system that projects measurement light and detects interference light (LC) between the return light of the measurement light from the subject and the reference light.

According to such a configuration, it is possible to compensate for the decrease in the amount of light to the frontal eye observation system due to the wavelength shift due to the dependence of the incident angle on the optical path synthesis surface while compensating for the decrease in the amount of light to the interference optical system.

In the ophthalmic apparatus according to some embodiments, the interfering optical system divides the light from the wavelength sweep light source into a reference light and a measurement light, projects the measurement light onto the eye to be inspected, and returns the measurement light from the eye to be inspected. Detects interference light between light and reference light.

According to such a configuration, the front eye observation system due to the wavelength shift due to the incident angle dependence on the optical path synthesis surface while compensating for the decrease in the amount of light to the interfering optical system capable of swept source type optical coherence stromography. It is possible to compensate for the decrease in the amount of light.

In the ophthalmic apparatus according to some embodiments, the anterior segment illumination system has a first illumination light source (50A) that irradiates illumination light in a wavelength range including the first peak wavelength and a wavelength range including the second peak wavelength. A second illumination light source (50B) for irradiating illumination light is included.

According to such a configuration, the first illumination light source and the second illumination light source compensate for the decrease in the amount of light to the anterior ocular segment observation system due to the wavelength shift corresponding to the upper end and the lower end of the incident angle range with a simple configuration. be able to.

According to such a configuration, it is possible to reliably compensate for the decrease in the amount of light to the anterior ocular segment observation system due to the wavelength shift corresponding to the upper end and the lower end of the incident angle range.

<Others>
The embodiments shown above are merely examples for carrying out the present invention. A person who intends to carry out the present invention can make arbitrary modifications, omissions, additions, etc. within the scope of the gist of the present invention.

1 Z alignment system 2 XY alignment system 3 kerato measurement system 4 fixation projection system 5 anterior eye observation system 6 reflex measurement projection system 7 reflex measurement light receiving system 8 OCT optical system 9 processing unit 51 objective lens 52 dichroic mirror 210 control unit 211 Main control unit 1000 Ophthalmic device

Claims (6)

With the objective lens
An anterior ocular segment observation system that detects the first return light of the illumination light from the anterior segment of the eye to be inspected through the objective lens.
An inspection optical system that projects light onto the optometry through the objective lens and detects the second return light from the optometry.
An optical path synthesis member that synthesizes the optical path of the inspection optical system and the optical path of the anterior segment observation system on an optical path synthesis surface arranged at an angle with respect to the optical axis of the objective lens.
An anterior segment illumination system that illuminates the anterior segment with illumination light in a wavelength range including a transmission center wavelength corresponding to the incident angle of the first return light to the optical path composite surface.
Including
An optical film is formed on the optical path composite surface so that the film thickness changes according to the position of the incident end surface of the light so as to compensate for the incident angle dependence of the second return light.
In the anterior segment illumination system, the wavelength is shifted by the shift corresponding to the upper end of the incident angle of the first return light with respect to the optical path composite surface with respect to the reference transmission center wavelength based on the light transmission characteristics on the optical path composite surface. The first peak wavelength corresponding to the first transmission center wavelength and the second transmission center wavelength corresponding to the second transmission center wavelength whose wavelength is shifted by the shift corresponding to the lower end of the incident angle with respect to the optical path synthesis surface with respect to the reference transmission center wavelength. An ophthalmic apparatus that illuminates the anterior segment of the eye with illumination light in a wavelength range including two peak wavelengths . The anterior segment illumination system has a wavelength including a peak wavelength corresponding to a transmission center wavelength in which the wavelength is shifted by a shift corresponding to the incident angle with respect to a reference transmission center wavelength based on the light transmission characteristics on the optical path synthesis surface. The ophthalmic apparatus according to claim 1, wherein the anterior segment of the eye is illuminated with illumination light in a range. The optical path composite surface is characterized in that an optical film is formed so that the film thickness changes according to the position of the incident end surface of the light so as to compensate for the incident angle dependence of the second return light. The ophthalmic apparatus according to claim 1 or 2. The inspection optical system divides the light from the light source into reference light and measurement light, projects the measurement light onto the eye to be inspected through the objective lens, and returns light of the measurement light from the eye to be inspected and the measurement light. The ophthalmic apparatus according to any one of claims 1 to 3, further comprising an interference optical system for detecting interference light with reference light. The interference optical system divides the light from the wavelength sweep light source into a reference light and a measurement light, projects the measurement light onto the eye to be inspected, and combines the return light of the measurement light from the eye to be inspected and the reference light. The ophthalmic apparatus according to claim 4, wherein the ophthalmic apparatus is characterized by detecting interfering light. The anterior eye illumination system is
The first illumination light source that irradiates the illumination light in the wavelength range including the first peak wavelength,
The second illumination light source that irradiates the illumination light in the wavelength range including the second peak wavelength, and the second illumination light source.
The ophthalmic apparatus according to any one of claims 1 to 5, wherein the ophthalmic apparatus comprises.

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