ophthalmic devices

Abstract

To provide a novel technology that removes cornea reflected light with a simple configuration while reducing impact of a cornea shape of a subject eye.SOLUTION: An ophthalmologic apparatus includes a projection optical system, a light receiving optical system, and a deflection member. The projection optical system projects light to an ocular fundus of a subject eye. The light receiving optical system receives return light from a subject eye. The deflection member can be disposed in a position of substantially optically conjugating with an ocular fundus and leads the return light to the light receiving optical system while deflecting the return light.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an ophthalmic apparatus. [Background technology]

[0002] Ophthalmic devices used for screening eye diseases and other purposes are required to be able to easily observe and photograph the fundus of the subject's eye over a wide field of view. A scanning laser ophthalmoscope (SLO) is known as such an ophthalmic device. SLOs can form an image of the fundus by scanning the fundus with light and detecting the returned light with a light-receiving device.

[0003] It is known that in SLO, artifacts may appear in the generated fundus image due to noise light other than the light returned from the fundus, such as light reflected from the cornea and the objective lens surface.

[0004] Therefore, various methods have been proposed for removing noise light contained in the return light from the fundus.

[0005] For example, Patent Document 1 discloses a method for eliminating most of the corneal reflected light from the return light from the fundus by forming an image of the corneal reflected light on a hole formed in a perforated mirror.For example, Patent Document 2 discloses a method for providing a pinhole in a light receiving optical system at a position optically conjugate with the fundus, and preventing unnecessary reflected light from the lens surface of the objective lens from passing through the pinhole. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2019-072027 [Patent Document 2] Patent Publication No. 2021-153890 Summary of the Invention [Problem to be solved by the invention]

[0007] Light irradiated onto the fundus through the pupil of the subject's eye is scattered (including reflected) by the cornea. The shape of the cornea varies from eye to eye. This means that the state of light scattering at the cornea varies from eye to eye. The methods disclosed in Patent Documents 1 and 2 do not take into account differences in corneal shape, and therefore, depending on the eye being examined, it may not be possible to sufficiently remove corneal reflected light contained in the light returning from the fundus, or some of the light reflected from the fundus may be removed along with the corneal reflected light. As such, conventional methods have the problem of being affected by the shape of the cornea of ​​the subject's eye.

[0008] Therefore, there is a demand for a technology that can remove noise light (particularly corneal reflected light) with a simple configuration while reducing or eliminating the influence of the shape of the cornea of ​​the subject's eye.

[0009] The present invention has been made in consideration of the above circumstances, and its purpose is to provide a new technology for removing corneal reflected light with a simple configuration while reducing the influence of the shape of the cornea of ​​the test eye. [Means for solving the problem]

[0010] A first aspect of the embodiment is an ophthalmic device including a projection optical system that projects light onto the fundus of the test eye, a light-receiving optical system that receives returning light from the test eye, and a deflection member that can be positioned at a position that is approximately optically conjugate with the fundus and deflects the returning light and guides it to the light-receiving optical system. A second aspect of the embodiment is the first aspect, which includes an optical scanner that can be positioned at a position that is approximately optically conjugate with the iris of the test eye, wherein the projection optical system projects light onto the fundus via the optical scanner, the light receiving optical system receives the returning light via the optical scanner, and the deflection member can be positioned at a position that is approximately optically conjugate with the fundus between the optical scanner and the light receiving optical system. A third aspect of the embodiment is the second aspect, which includes a first light focusing member arranged between the optical scanner and the deflection member, and the deflection member is arranged at or near the rear focal position of the first light focusing member. A fourth aspect of the embodiment is the second or third aspect, and includes a concave mirror having a concave reflective surface and positioned between the optical scanner and the subject's eye, wherein the concave mirror guides light deflected by the optical scanner to the fundus and also guides the return light from the subject's eye to the optical scanner. A fifth aspect of the embodiment is the fourth aspect, which includes a reflective member arranged between the optical scanner and the concave mirror and having a reflective surface arranged opposite the reflective surface of the concave mirror, wherein the reflective member guides the light deflected by the optical scanner to the reflective surface of the concave mirror and also guides the returning light from the reflective surface of the concave mirror to the optical scanner. In a sixth aspect of the embodiment, in the fourth or fifth aspect, the concave mirror is an ellipsoidal mirror having an ellipsoidal reflective surface, the optical scanner is positioned at or near a first focal position of the reflective surface of the ellipsoidal mirror, and the iris of the subject's eye can be positioned at or near a second focal position of the reflective surface of the ellipsoidal mirror. A seventh aspect of the embodiment is any one of the first to sixth aspects, further comprising a black dot plate disposed between the deflector and the light receiving optical system. An eighth aspect of the embodiment is the seventh aspect, which includes a second light focusing member arranged between the deflection member and the black spot plate, and the deflection member is arranged at or near the front focal position of the second light focusing member. In a ninth aspect of the embodiment, in the seventh or eighth aspect, the size of the black dot plate for removing corneal reflected light is larger than the size of the deflection surface of the deflection member. In a tenth aspect of the embodiment, in the ninth aspect, the size of the deflection surface is configured to be changeable. In an eleventh aspect of the embodiment, in the ninth or tenth aspect, the corneal reflection removal size is configured to be changeable. In a twelfth aspect of the embodiment, in any one of the ninth to eleventh aspects, the corneal reflection removal size is changed in accordance with the size of the deflection surface. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a new technique for removing corneal reflected light with a simple configuration while reducing the influence of the shape of the cornea of ​​the subject's eye. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a schematic diagram illustrating an example of the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 2] FIG. 2 is a schematic diagram illustrating an example of a specific configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 3] 1 is an explanatory diagram illustrating a configuration of an optical system of an ophthalmic apparatus according to an embodiment. [Figure 4] 1 is an explanatory diagram illustrating a configuration of an optical system of an ophthalmic apparatus according to an embodiment. [Figure 5] 1 is an explanatory diagram illustrating a configuration of an optical system of an ophthalmic apparatus according to an embodiment. [Figure 6] 1 is an explanatory diagram illustrating a configuration of an optical system of an ophthalmic apparatus according to an embodiment. [Figure 7] FIG. 2 is a functional block diagram illustrating an example of the configuration of a control system of the ophthalmologic apparatus according to the embodiment. [Figure 8] FIG. 10 is a schematic diagram illustrating an example of the configuration of an optical system of an ophthalmologic apparatus according to a modified example of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] An example of an embodiment of an ophthalmic device according to the present invention will be described in detail with reference to the drawings. Note that the contents of documents cited in this specification and any publicly known techniques can be incorporated into the following embodiments.

[0014] An ophthalmic apparatus according to some embodiments is configured to project light onto an eye to be examined and receive light returning from the eye to be examined while reducing or eliminating noise light. At this time, noise light (particularly corneal reflected light) is removed from the light returning from the eye to be examined, and the apparatus is configured to receive light returning with an improved signal-to-noise ratio (S / N ratio) using fundus reflected light as signal light. The ophthalmic apparatus is capable of forming an image of the eye to be examined using the result of receiving the light returning with an improved S / N ratio. The ophthalmic apparatus according to some embodiments further includes an optical scanner, and is a scanning laser ophthalmoscope (SLO) that deflects light using the optical scanner, projects the light onto the eye to be examined, and receives the light returning as described above.

[0015] In this specification, images acquired by SLO may be collectively referred to as SLO images, and the measurement operation for forming an SLO image may be referred to as SLO measurement.

[0016] An ophthalmic device according to some embodiments further includes one or more of an ophthalmic imaging device, an ophthalmic measurement device, and an ophthalmic treatment device. Examples of the ophthalmic imaging device included in the ophthalmic device include one or more of a fundus camera, a slit lamp ophthalmoscope, and a surgical microscope. Examples of the ophthalmic measurement device included in the ophthalmic device include one or more of an eye refraction examination device, a tonometer, a specular microscope, a wavefront analyzer, a perimeter, and a microperimeter. Examples of the ophthalmic treatment device included in the ophthalmic device include one or more of a laser treatment device, a surgical device, and a surgical microscope.

[0017] In the following embodiments, a position that is approximately optically conjugate with the fundus of the subject's eye may be referred to as a "fundus conjugate position." In this case, the "fundus conjugate position" refers to a position that is optically conjugate with the fundus or its vicinity. Similarly, a position that is approximately optically conjugate with the iris (pupil) of the subject's eye may be referred to as an "iris conjugate position" (pupil conjugate position). In this case, the "iris conjugate position" refers to a position that is optically conjugate with the iris or its vicinity.

[0018] FIG. 1 shows an example of the configuration of an optical system of an ophthalmic apparatus according to an embodiment.

[0019] The ophthalmologic apparatus 1 according to the embodiment includes a projection optical system 10, a light receiving optical system 20, and a deflection member 50.

[0020] The projection optical system 10 projects light onto the fundus Ef through the pupil of the subject's eye E. The projection optical system 10 includes a light source and a projection lens, and is capable of projecting light having a predetermined wavelength range or light having any one of two or more wavelength ranges with different central wavelengths onto the subject's eye E. In some embodiments, the projection optical system 10 projects synthesized light obtained by combining light having two or more wavelength ranges onto the subject's eye E. In some embodiments, the projection optical system 10 sequentially selects any one of two or more wavelength ranges and sequentially projects light having the selected wavelength range onto the subject's eye E.

[0021] The light receiving optical system 20 receives return light from the fundus oculi Ef. The light receiving optical system 20 includes an imaging lens and a light receiving element, and is capable of receiving return light having a wavelength range corresponding to the wavelength range of the light projected by the projection optical system 10. In some embodiments, the light receiving optical system 20 includes two or more light receiving elements having different wavelength ranges with light receiving sensitivity effective for detecting light, and each light receiving element is configured to receive return light separated by wavelength for each wavelength range. In some embodiments, the light receiving optical system 20 is configured to sequentially or simultaneously receive return light having two or more wavelength ranges with a single light receiving element.

[0022] The deflection member 50 deflects the returning light from the fundus Ef and guides it to the light receiving optical system 20. The deflection member 50 can be placed at a position P (fundus conjugate position) that is approximately optically conjugate with the fundus Ef on the optical path of the returning light from the fundus Ef. An example of the deflection member 50 is a reflecting mirror (plane mirror).

[0023] The deflecting member 50 can deflect the optical axis of the optical path of the return light from the subject's eye E in any direction. This improves the degree of freedom in arranging the subsequent optical system, and enables the optical system configuration of the ophthalmic apparatus 1 to be made compact.

[0024] Furthermore, the deflection member 50 can remove noise light other than the light reflected from the fundus Ef (fundus reflected light) from the returned light from the subject's eye E, while guiding all of the reflected light from the fundus Ef to the light-receiving optical system 20. This makes it possible to guide the returned light with an improved S / N ratio of the fundus reflected light to the light-receiving optical system 20 while reducing the influence of the shape of the cornea of ​​the subject's eye E.

[0025] Furthermore, the size of the deflection surface of the deflection member 50 for the returning light can be adjusted to the spot size of the fundus reflected light, thereby making it possible to reduce the size of the deflection surface. For example, the deflection member 50 may be a small-diameter round mirror with a small diameter of the deflection surface.

[0026] In this embodiment, the ophthalmic apparatus 1 includes an optical path combining member 30 that optically combines the optical path of the projection optical system 10 with the optical path of the light receiving optical system 20. In some embodiments, the optical path combining member 30 coaxially combines the projection optical system 10 with the light receiving optical system 20 so that their optical axes are substantially aligned. Examples of the optical path combining member 30 include a beam splitter and a quick return mirror. Examples of the beam splitter include a half mirror, a dichroic mirror, and a polarizing beam splitter (PBS).

[0027] In some embodiments, the ophthalmic apparatus 1 further includes a black dot plate 60 disposed between the deflecting member 50 and the light-receiving optical system 20. The black dot plate 60 is configured to block light passing through a predetermined area including a position corresponding to the optical axis of the optical path of light deflected by the deflecting member 50 toward the light-receiving optical system 20, or to reflect light passing through the predetermined area in a direction different from the optical axis. This allows the black dot plate 60 to remove corneal reflected light deflected by the deflecting member 50 (corneal reflected light not removed by the deflecting member 50) from the returning light from the subject's eye E.

[0028] In the ophthalmologic apparatus 1 having the above-described configuration, light from the projection optical system 10 is reflected by the optical path connecting member 30 toward the subject's eye E and projected onto the fundus Ef through the pupil. Return light from the subject's eye E, including reflected light from the fundus Ef (fundus reflected light) and noise light such as corneal reflected light, passes through the optical path connecting member 30 and is deflected by the deflecting member 50. At this time, all of the fundus reflected light among the return light from the subject's eye E is deflected toward the light-receiving optical system 20, and a portion of the corneal reflected light (a portion of the noise light) is removed from the return light from the subject's eye E guided to the light-receiving optical system 20. The return light deflected by the deflecting member 50 is guided to the light-receiving optical system 20 via the black dot plate 60. At this time, the corneal reflected light deflected by the deflecting member 50 (corneal reflected light not removed by the deflecting member 50) is removed by the black dot plate 60. The light-receiving optical system 20 detects the return light with an improved S / N ratio of the fundus reflected light.

[0029] Therefore, it is possible to remove the corneal reflected light with a simple configuration while reducing the influence of the shape of the cornea of ​​the eye E to be examined.

[0030] A specific configuration example of the ophthalmologic apparatus 1 according to the embodiment will be described below.

[0031] In the following, an example will be described in which the ophthalmic apparatus 1 includes an optical scanner and an ellipsoidal mirror having an ellipsoidal reflecting surface, and is configured to be able to acquire a wide-angle fundus image, but the configuration according to the embodiment is not limited to this. For example, the ophthalmic apparatus 1 may include a concave mirror having a concave reflecting surface or a free-form mirror having a free-form reflecting surface, instead of the ellipsoidal mirror.

[0032] 2 to 6 show specific configuration examples of the optical system of the ophthalmologic apparatus 1 according to the embodiment. In Fig. 2 to Fig. 6, parts similar to those in Fig. 1 are given the same reference numerals, and descriptions thereof will be omitted where appropriate. In Fig. 3 to Fig. 6, parts similar to those in Fig. 2 are given the same reference numerals, and descriptions thereof will be omitted where appropriate. Figs. 2, 5, and 6 show a fundus conjugate position P, which is a position that is approximately optically conjugate with the fundus Ef of the subject's eye E, and an iris conjugate position (pupil conjugate position) Q, which is a position that is approximately optically conjugate with the iris (pupil) of the subject's eye E.

[0033] FIG. 2 shows an example of the optical system configuration of the ophthalmic apparatus 1 when acquiring a two-color pseudo-color fundus image. In FIG. 2, the optical axis direction of the optical system of the ophthalmic apparatus 1 is represented as the z direction, the vertical direction perpendicular to the z direction is represented as the y direction, and the horizontal direction perpendicular to the z direction is represented as the x direction. Note that in FIG. 2, the direction from the fundus Ef toward the iris is represented as the z direction, but the z direction may also be the direction from the iris toward the fundus Ef. FIG. 3 is an explanatory diagram of the plane mirror 71 in FIG. 2. FIG. 4 is a schematic diagram showing the relationship between the position of the deflection surface of the optical scanner 40 and the position of the reflecting surface of the plane mirror 71. FIG. 5 is a schematic diagram showing the optical path of fundus reflected light in the ophthalmic apparatus 1 shown in FIG. 2. FIG. 6 is a schematic diagram showing the optical path of corneal reflected light in the ophthalmic apparatus 1 shown in FIG. 2.

[0034] As shown in FIG. 2, the ophthalmologic apparatus 1 includes a projection optical system 10, a light receiving optical system 20, an optical path combining member 30, an optical scanner 40, a deflecting member 50, an ellipsoidal mirror 70, and a plane mirror 71.

[0035] Furthermore, in the optical path between the optical path coupling member 30 and the optical scanner 40, a quarter-wave plate (¼λ plate) 31 and a condenser lens 32 are arranged in this order from the optical scanner 40 side. In the optical path between the optical path coupling member 30 and the deflection member 50, a reflecting mirror 33 and a relay lens 51 are arranged in this order from the optical path coupling member 30 side. In the optical path between the deflection member 50 and the light receiving optical system 20, a relay lens 52 and a black dot plate 60 are arranged in this order from the deflection member 50 side.

[0036] (Projection optical system 10) The projection optical system 10 includes light sources 11A and 11B, collimator lenses 12A and 12B, a dichroic mirror 13, and a polarizing plate 14.

[0037] Light source 11A is a red light source that outputs light having a red wavelength region. Light source 11B is a green light source that outputs light having a green wavelength region. Each of light sources 11A and 11B is disposed at a fundus conjugate position P. Each of light sources 11A and 11B may be an LD (Laser Diode) light source, an LED (Light Emitting Diode) light source, a Super Luminescent Diode (SLD) light source, or a Laser Driven Light Source (LDLS) light source.

[0038] The collimator lens 12A collimates the light output by the light source 11A and guides it to the dichroic mirror 13. The collimator lens 12B collimates the light output by the light source 11B and guides it to the dichroic mirror 13.

[0039] Dichroic mirror 13 transmits light in the green wavelength region and reflects light in the red wavelength region. Dichroic mirror 13 reflects the light collimated by collimator lens 12A toward polarizing plate 14, and transmits the light collimated by collimator lens 12B and guides it to polarizing plate 14.

[0040] The polarizing plate 14 transmits light having a polarization component in a predetermined first polarization direction among the polarization components of the light guided from the dichroic mirror 13, and guides the light to the optical path combining member 30. By having the light guided from the dichroic mirror 13 pass through the polarizing plate 14, it is possible to suppress variations in the polarization state of the light output from each of the light sources 11A and 11B.

[0041] In addition, in Figure 2, the projection optical system 10 may further include a blue light source that outputs light having a blue wavelength range and a collimator lens that collimates the light output by the blue light source, and the ophthalmic device 1 may be configured to be able to acquire three-color fundus images.

[0042] 2 is, for example, a polarizing beam splitter (PBS). As described above, the optical path combining member 30 coaxially combines the projection optical system 10 and the light receiving optical system 20. The optical path combining member 30 reflects light having a polarization component in a first polarization direction that has passed through the polarizing plate 14 and guides it to a condenser lens 32, and also transmits light having a polarization component in a second polarization direction orthogonal to the first polarization direction, among the return light from the subject's eye E, and guides it to a reflecting mirror 33.

[0043] The condenser lens (convex lens) 32 collects the light from the projection optical system 10 reflected by the optical path combining member 30, and forms (focuses) an image at, for example, the position shown in FIG. 2 (the fundus conjugate position P between the plane mirror 71 and the optical scanner 40). This allows the focused light to be reflected by the reflecting surface of the ellipsoidal mirror 70, and the light, which has been made into approximately parallel light, can be incident on the subject's eye E. As a result, the optical system inside the ophthalmologic apparatus 1 can be positioned based on an emmetropic eye. In particular, an existing model eye can be used when adjusting the optical system, which enables cost reduction.

[0044] The light transmitted through the condenser lens 32 is guided to the quarter-wave plate 31. The quarter-wave plate 31 imparts a phase difference to the light that has been linearly polarized by the polarizing plate 14, changing the polarization state to circular polarization. This makes it possible to receive returning light that changes according to the polarization characteristics of the subject's eye E (tissue within the eyeball) and contains averaged polarization information. The quarter-wave plate 31 also changes the polarization state of the returning light from the subject's eye E to linear polarization.

[0045] The light that has passed through the quarter-wave plate 31 is guided to the optical scanner 40 .

[0046] (Optical Scanner 40) The optical scanner 40 deflects the light transmitted through the condenser lens 32. The deflection surface of the optical scanner 40 can be arranged at the iris conjugate position Q. In addition, the deflection surface of the optical scanner 40 is arranged at or near a first focal position of two focal positions of an ellipsoidal reflecting surface of an ellipsoidal mirror 70 described below.

[0047] The optical scanner 40 is, for example, a one-axis or two-axis optical scanner.

[0048] When the optical scanner 40 is a uniaxial optical scanner, the optical scanner 40 moves the projection position of light on the fundus Ef in a predetermined axial direction (x direction or y direction) by one-dimensionally changing the orientation of the deflection plane within a predetermined one-dimensional deflection angle range including a predetermined scan center direction. Examples of such an optical scanner 40 include a galvanometer mirror, a resonant mirror, a polygon mirror, or a uniaxial MEMS (Micro Electro Mechanical Systems: hereinafter, MEMS) mirror.

[0049] When the optical scanner 40 is a two-axis optical scanner, the optical scanner 40 moves the projection position of light on the fundus Ef in two predetermined axial directions (x and y directions) by two-dimensionally changing the orientation of the deflection surface within a predetermined two-dimensional deflection angle range including a predetermined scan center direction. Examples of such an optical scanner 40 include a combination of a uniaxial first optical scanner and a uniaxial second optical scanner, and a two-axis MEMS mirror. When the first optical scanner and the second optical scanner are combined, for example, the first optical scanner changes the projection position of light on the fundus Ef in the x direction, and the second optical scanner changes the projection position of light on the fundus Ef in the y direction. One of the first and second optical scanners may be a low-speed scanner such as a galvanometer mirror, and the other may be a high-speed scanner such as a resonant mirror, a polygon mirror, or an MEMS mirror. In this case, the deflection surface of the first optical scanner or the second optical scanner, an intermediate position between the first and second optical scanners, or the deflection surface of the two-axis MEMS mirror is located at or near a first of two focal positions of the ellipsoidal reflecting surface of the ellipsoidal mirror 70 described below. Examples of scan modes performed by such an optical scanner 40 include horizontal scan, vertical scan, cross scan, radial scan, circular scan, concentric circle scan, spiral scan, and Lissajous scan.

[0050] The optical scanner 40 deflects light from the projection optical system 10 and guides it to the plane mirror 71, and also guides the returning light from the plane mirror 71 to the light-receiving optical system 20. That is, the projection optical system 10 projects light onto the fundus Ef via the optical scanner 40, and the light-receiving optical system 20 is configured to receive the returning light via the optical scanner.

[0051] (Flat mirror 71) The plane mirror 71 is disposed between the optical scanner 40 and the ellipsoidal mirror 70 serving as a concave mirror, and has a reflecting surface disposed to face the reflecting surface of the ellipsoidal mirror 70. The plane mirror 71 guides the light deflected by the optical scanner 40 to the reflecting surface of the ellipsoidal mirror 70, and also guides the returning light from the reflecting surface of the ellipsoidal mirror 70 to the optical scanner 40.

[0052] 3, two focal positions F1 and F2 that are optically conjugate with respect to the ellipsoidal reflecting surface (ellipsoid) of the ellipsoidal mirror 70 are defined. In this embodiment, the focal position F1 can be moved to a focal position F1' by arranging a plane mirror 71 so as to face the reflecting surface of the ellipsoidal mirror 70. Like the focal position F1, the focal position F1' also has an optically conjugate relationship with the focal position F2.

[0053] In this way, by placing the flat mirror 71 between the optical scanner 40 and the ellipsoidal mirror 70, space can be created above (in the y direction) the subject's eye E (i.e., the focal position F2) that is positioned during SLO measurement, and space can be secured for placing the subject's forehead, etc.

[0054] In addition, by adjusting the position of the plane mirror 71 and the orientation of the reflecting surface, the incident angle of the returning light from the plane mirror 71 relative to the deflection surface of the optical scanner 40 (the exit angle of the light deflected toward the plane mirror 71) can be adjusted.

[0055] As shown in Fig. 4, the optical scanner 40 changes the orientation of the deflection surface within a predetermined deflection angle range around a predetermined scan center direction SC. For example, by changing the position of the plane mirror 71 relative to the deflection surface of the optical scanner 40, the angle α between the scan center direction SC and the incident direction of the returning light from the plane mirror 71 changes. Fig. 4 shows a case where the position of the plane mirror 71 is changed relative to the optical scanner 40, but the same applies when the orientation of the reflective surface of the plane mirror 71 is changed relative to the orientation of the deflection surface of the optical scanner 40.

[0056] Generally, the narrower the deflection angle range centered on the scan center direction SC shown in Fig. 4, the better the linearity, speed, and accuracy of the deflection operation of the optical scanner 40. Therefore, in the embodiment, at least one of the position and orientation of the reflecting surface of the plane mirror 71 is adjusted so that the angle α between the scan center direction SC on the deflection surface of the optical scanner 40 and the incident direction of the returning light from the plane mirror 71 (the output angle of the light deflected toward the plane mirror 71) is 45 degrees or less (i.e., the angle α is an acute angle). This makes it possible to ensure the linearity, speed, and accuracy of the deflection operation of the optical scanner 40 with a simple configuration.

[0057] (Ellipsoidal mirror 70) As described above, the ellipsoidal mirror 70 has an ellipsoidal reflecting surface. The ellipsoidal mirror 70 is an example of a concave mirror. In some embodiments, the ophthalmic apparatus 1 includes a concave mirror having a concave reflecting surface instead of the ellipsoidal mirror 70, and the concave mirror guides light deflected by the optical scanner 40 to the fundus Ef and guides returning light from the subject's eye E to the optical scanner 40. In some embodiments, the reflecting surface of the concave mirror is formed to be a free-form surface.

[0058] The deflection surface of the optical scanner 40 is placed at or near the focal position F1' defined by the reflecting surface of the ellipsoidal mirror 70, and the iris of the subject's eye E can be placed at or near the focal position F2.

[0059] The ellipsoidal mirror 70 guides the light reflected by the plane mirror 71 and deflected by the optical scanner 40 to the fundus oculi Ef, and also guides the returning light from the subject's eye E to the optical scanner 40 via the plane mirror 71.

[0060] As described above, the light output from the projection optical system 10 passes through the optical path coupling member 30, the condenser lens 32, the quarter-wave plate 31, the optical scanner 40, the plane mirror 71, and the ellipsoidal mirror 70, and is projected onto the subject's eye E. Most of the light projected onto the subject's eye E is irradiated onto the fundus Ef through the pupil, and some of it is reflected by the cornea or scattered by tissues within the eye. Noise light, including light reflected from the fundus Ef and light reflected by the cornea, is guided as returned light from the subject's eye E to the optical path coupling member 30 via the ellipsoidal mirror 70, the plane mirror 71, the optical scanner 40, the quarter-wave plate 31, and the condenser lens 32.

[0061] Of the return light from the test eye E that has been guided to the optical path coupling member 30, light having a polarization component in a second polarization direction that is perpendicular to the first polarization direction of the light projected onto the test eye E passes through the optical path coupling member 30 and is guided to the reflecting mirror 33.

[0062] The reflecting mirror 33 guides the returning light that has passed through the optical path coupling member 30 to the deflection member 50 via the relay lens 51 .

[0063] (Relay Lens 51) The relay lens (convex lens) 51 is disposed between the reflecting mirror 33 (optical scanner 40) and the deflecting member 50. The deflecting member 50 is disposed at or near the rear focal position of the relay lens 51. This allows the fundus reflected light, which is part of the return light that is reflected by the reflecting surface of the ellipsoidal mirror 70 and transmitted through the condenser lens 32, to be imaged (focused) on the deflecting surface of the deflecting member 50.

[0064] (Deflection member 50) The deflection member 50 (deflection surface) can be placed at a fundus conjugate position P between the optical scanner 40 and the light-receiving optical system 20. The deflection member 50 guides all of the reflected light from the fundus Ef (fundus reflected light) among the returned light from the subject's eye E that has passed through the relay lens 51 to the relay lens 52 (light-receiving optical system 20). This makes it possible to remove most of the noise light, including the reflected light from the cornea. As a result, it becomes possible to guide the returned light, with an improved S / N ratio of the fundus reflected light, to the light-receiving optical system 20 while reducing the influence of the shape of the cornea of ​​the subject's eye E.

[0065] (Relay lens 52) The relay lens (convex lens) 52 is disposed between the deflection member 50 and the black dot plate 60. The deflection member 50 is disposed at or near the front focal position of the relay lens 52. This allows the return light (including part of the corneal reflected light) polarized by the deflection member 50 to be converted into approximately parallel light.

[0066] (black dot board 60) The black dot plate 60 is disposed between the relay lens 52 and the light receiving optical system 20. The black dot plate 60 is desirably disposed in a position on the optical path between the deflection member 50 and a detector of the light receiving optical system 20, which will be described later, where the beam diameter of the return light, including the fundus reflected light, is large. In FIG. 2, the black dot plate 60 is disposed in a position on the optical path where the return light is converted into approximately parallel light by the relay lens 52. This makes it possible to remove the corneal reflected light deflected by the deflection member 50 (the corneal reflected light not removed by the deflection member 50) while allowing most of the fundus reflected light to pass through (while reducing the proportion of fundus reflected light removed) among the return light blocked by the black dot plate 60.

[0067] (Receiving optical system 20) The light receiving optical system 20 includes detectors 21A and 21B, imaging lenses 22A and 22B, and a beam splitter .

[0068] Detector 21A includes one or more light-receiving elements having light-receiving sensitivity effective for detection in the wavelength region of the light output by light source 11A. Imaging lens 22A is disposed between beam splitter 23 and detector 21A, and focuses the returning light from beam splitter 23 onto the detection surface of detector 21A.

[0069] Detector 21B includes one or more light-receiving elements having light-receiving sensitivity effective for detection in the wavelength region of the light output by light source 11B. Imaging lens 22B is disposed between beam splitter 23 and detector 21B, and focuses the returning light from beam splitter 23 on the detection surface of detector 21B.

[0070] Each of the detectors 21A and 21B may be, for example, an avalanche photodiode (APD) or a photomultiplier tube (PMT).

[0071] Beam splitter 23 guides the returned light that has passed through black dot plate 60 to both imaging lenses 22A and 22B. In some embodiments, beam splitter 23 is a dichroic mirror that transmits light in the green wavelength region of the returned light and reflects light in the red wavelength region. In some embodiments, beam splitter 23 is a half mirror that reflects a portion of the returned light and transmits the remaining portion.

[0072] In the above-described configuration, the return light transmitted through the optical path coupling member 30 is reflected by the reflecting mirror 33 and focused (imaged) on the deflection surface of the deflection member 50 by the relay lens 51. The deflection member 50 deflects the return light transmitted through the relay lens 51, thereby directing all of the light reflected from the fundus Ef (fundus reflected light) of the return light to the relay lens 52 (light receiving optical system 20) and suppressing most of the noise light such as corneal reflected light from being directed to the relay lens 52. The return light deflected by the deflection member 50 is converted into approximately parallel light by the relay lens 52 and directed to the black dot plate 60. At the position on the optical path where the return light is converted into approximately parallel light, the black dot plate 60 further removes the corneal reflected light deflected by the deflection member 50 while passing most of the fundus reflected light of the return light.

[0073] Of the return light that has passed through the black dot plate 60, the return light having a red wavelength range is reflected by the beam splitter 23 and is imaged on the detection surface of the detector 21A by the imaging lens 22A. The detector 21A detects the return light that has been imaged on the detection surface. Of the return light that has passed through the black dot plate 60, the return light having a green wavelength range is transmitted through the beam splitter 23 and is imaged on the detection surface of the detector 21B by the imaging lens 22B. The detector 21B detects the return light that has been imaged on the detection surface.

[0074] 5, all of the fundus-reflected light among the returning light from the subject's eye E is reflected by the deflecting surface of the deflecting member 50, converted into approximately parallel light by the relay lens 52, and received by the detectors 21A and 21B. On the other hand, as shown in FIG. 6, most of the cornea-reflected light among the returning light from the subject's eye E is removed without being deflected by the deflecting member 50, and the remaining part of the cornea-reflected light is blocked by the black dot plate 60.

[0075] The relay lens 51 is an example of a "first light focusing member" according to the embodiment. The relay lens 52 is an example of a "second light focusing member" according to the embodiment. The ellipsoidal mirror 70 is an example of a "concave mirror" according to the embodiment. The plane mirror 71 is an example of a "reflective member" according to the embodiment. The focal position F1' (F1) is an example of a "first focal position" according to the embodiment. The focal position F2 is an example of a "second focal position" according to the embodiment.

[0076] Fig. 7 shows an example of the configuration of a control system of the ophthalmologic apparatus 1 according to the embodiment. In Fig. 7, the same parts as those in Figs. 1 to 6 are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0077] The control system of the ophthalmic apparatus 1 is mainly composed of a control unit 100. The control unit 100 controls each unit of the ophthalmic apparatus 1. The control unit 100 includes a main control unit 101 and a storage unit 102. The functions of the main control unit 101 are realized by, for example, a processor. The storage unit 102 stores in advance computer programs for controlling the ophthalmic apparatus 1. These computer programs include programs for controlling various light sources, a program for controlling an optical scanner, a program for controlling various detectors, a program for image formation, and a program for a user interface. The main control unit 101 operates in accordance with these computer programs, causing the control unit 100 to execute control processing.

[0078] In this specification, the term "processor" refers to a circuit such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), or a programmable logic device (e.g., an SPLD (Simple Programmable Logic Device), a CPLD (Complex Programmable Logic Device), or an FPGA (Field Programmable Gate Array)). The processor realizes the functions according to the embodiment by, for example, reading and executing a program stored in a memory circuit or a storage device.

[0079] (Main control unit 101) The main control unit 101 controls the projection optical system 10, the light receiving optical system 20, the optical scanner 40, the image forming unit 200, the operation unit 110, and the display unit 120.

[0080] Control of the projection optical system 10 includes control of the light sources 11A and 11B. Control of the light sources 11A and 11B includes turning the light sources on and off, adjusting the light intensity, adjusting the aperture, etc. For example, if the wavelength range of the light output by the light source included in the projection optical system 10 can be changed, the main control unit 101 can control the light source to change the wavelength range of the output light.

[0081] Control of the light receiving optical system 20 includes control of the detectors 21A and 21B. Control of the detectors 21A and 21B includes adjustment of the exposure of the light receiving elements, adjustment of the light receiving range on the detection surface, gain adjustment, detection rate adjustment, etc. For example, if the detector included in the light receiving optical system 20 can change the wavelength range of light for which it has effective light receiving sensitivity for detection, the main control unit 101 can control the detector to change the wavelength range of light for which it has effective light receiving sensitivity for detection.

[0082] Control of the optical scanner 40 includes control of the scan position on the fundus Ef, the scan range (scan start position, scan end position), scan speed, scan mode, scan center direction, and the like.

[0083] The main control unit 101 is also capable of controlling the image forming unit 200 .

[0084] (Image forming unit 200) The image forming unit 200 forms image data of a fundus image (SLO image) of the subject's eye E based on detection signals input from the detectors 21A and 21B and a pixel position signal input from the control unit 100. Here, the pixel position signal corresponds to a deflection control signal for the optical scanner 40. For example, a pixel position signal indicating a scan position within a scan range on the fundus Ef scanned by the optical scanner 40 corresponds to the deflection control signal. The image forming unit 200 can form a fundus image corresponding to the scan range by calculating, for a pixel position specified by the pixel position signal, a pixel value corresponding to the result of receiving returned light at the scan position corresponding to the pixel position.

[0085] The image forming unit 200 forms image data of a fundus image (SLO image) of the red component based on the detection signal obtained by the detector 21A and the pixel position signal from the control unit 100. The image forming unit 200 also forms image data of a fundus image of the green component based on the detection signal obtained by the detector 21B and the pixel position signal from the control unit 100. The image forming unit 200 aligns the fundus image of the red component with the fundus image of the green component and combines the two fundus images to form a pseudo-color fundus image of the red component and the green component.

[0086] Various images (image data) formed by the image forming unit 200 are stored in the storage unit 102, for example.

[0087] For example, the function of the image forming unit 200 is realized by an image forming processor that realizes the function of the image forming unit 200 .

[0088] (Storage unit 102) The storage unit 102 stores various types of data. Examples of data stored in the storage unit 102 include image data of fundus images, information about the subject's eye, etc. The information about the subject's eye includes information about the subject, such as a patient ID and name, and information about the subject's eye, such as identification information for the left eye or right eye.

[0089] The storage unit 102 also stores various programs and data for operating the ophthalmologic apparatus 1.

[0090] (Operation unit 110) The operation unit 110 includes an input device for the user to input information, operation instructions, etc. for operating the ophthalmologic apparatus 1. For example, the operation unit 110 includes various hardware keys and / or software keys. The main control unit 101 can receive operation details for the operation unit 110 and output control signals corresponding to the operation details to each unit.

[0091] (Display section 120) The display unit 120 is an output device that displays information provided by the ophthalmologic apparatus 1 to the user. The display unit 120 displays various types of information. For example, the display unit 120 includes a liquid crystal display or an organic EL display, and displays the above information under control of the main control unit 101. The information displayed on the display unit 120 includes information corresponding to the control results by the control unit 100, information (images) corresponding to the calculation results by the image forming unit 200, information (images) acquired by the light receiving optical system 20, information input by the user using the operation unit 110, and the like.

[0092] It is possible to configure at least a part of the operation unit 110 and at least a part of the display unit 120 integrally. A touch panel display is one example.

[0093] As described above, according to the embodiment, with a simple configuration, SLO measurement is performed on a scan range set on the fundus Ef using light from the projection optical system 10, and fundus reflected light from which at least corneal reflected light has been removed can be received among the returned light from the subject's eye E. At this time, after the returned light is deflected by the deflection member 50 arranged at a fundus conjugate position, the corneal reflected light can be removed using the black dot plate 60. Therefore, it is possible to receive returned light with an improved S / N ratio of fundus reflected light with a simple configuration while reducing the influence of the shape of the cornea of ​​the subject's eye E.

[0094] <Modification> The configuration of the ophthalmic apparatus according to the embodiment is not limited to the configuration described in Figures 1 to 7. For example, in the ophthalmic apparatus according to the embodiment, the projection optical system may include a single light source, and the light receiving optical system may include a single detector.

[0095] An example of the configuration of an optical system of an ophthalmic apparatus according to a modified example of the embodiment is shown in Fig. 8. In Fig. 8, the same parts as those in Fig. 2 are given the same reference numerals, and the description thereof will be omitted as appropriate.

[0096] The configuration of the ophthalmic device 1a according to the modified embodiment differs from the configuration of the ophthalmic device 1 shown in FIG. 2 in that a projection optical system 10a is provided instead of the projection optical system 10, and a light receiving optical system 20a is provided instead of the light receiving optical system 20.

[0097] The projection optical system 10a includes a light source 11C, a collimator lens 12C, and a polarizing plate .

[0098] The light source 11C is a light source that outputs light having a predetermined wavelength range. The light source 11C is disposed at a fundus conjugate position P. Like the light sources 11A and 11B, the light source 11C may be an LD light source, an LED light source, an SLD light source, or an LDLS light source. The collimator lens 12C collimates the light output by the light source 11C and guides it to the polarizing plate 14.

[0099] The light receiving optical system 20a includes a detector 21C and an imaging lens 22C.

[0100] Detector 21C includes one or more light-receiving elements having light-receiving sensitivity effective for detection in the wavelength region of light output by light source 11C. Imaging lens 22C is disposed between black dot plate 60 and detector 21C, and focuses the returning light that has passed through black dot plate 60 onto the detection surface of detector 21C. Detector 21C may be an APD or a PMT, similar to detectors 21A and 21B.

[0101] In this modification, the light-receiving optical system 20a may include two or more detectors having light-receiving sensitivity effective for detecting light having different wavelength regions, similar to the light-receiving optical system 20. In this case, the light source 11C outputs light having two or more wavelength regions with different center wavelengths, and two or more detectors included in the light-receiving optical system 20a to which returned light from the subject's eye E, which has been wavelength-separated for each wavelength region, is guided, are configured to receive the returned light having each wavelength region.

[0102] In this modification, the projection optical system 10a may include two or more light sources that output light having wavelength ranges with different center wavelengths, similar to the projection optical system 10. In this case, the detector 21C is configured to include one or more light-receiving elements that have light-receiving sensitivity effective for detecting return light having two or more wavelength ranges output by the two or more light sources.

[0103] In some embodiments or their modifications, the ophthalmologic apparatus 1 includes an internal fixation or an external fixation. In this case, the main controller 101 can present a fixation target to the subject's eye E so as to guide the fixation to a fixation position set manually or automatically.

[0104] In some embodiments or their variations, the ophthalmologic apparatus 1 includes a focusing lens. For example, the focusing lens is disposed in the optical path between the optical scanner 40 and the deflecting member 50. In this case, the main controller 101 can change the focal position of the returning light from the subject's eye E by controlling the focusing lens. In this case, the focusing lens is moved so that the fundus Ef and the deflecting member 50 are in a substantially optically conjugate relationship.

[0105] In some embodiments or their variations, the corneal reflected light removal size of the black dot plate 60 that blocks or reflects the corneal reflected light is larger than the size of the deflection surface of the deflection member 50. This makes it possible to almost completely remove the corneal reflected light while minimizing the size of the deflection surface of the deflection member 50.

[0106] In some embodiments or their modified examples, the size of the deflection surface of the deflection member 50 is configured to be changeable. For example, the main controller 101 may be able to change the size of the deflection surface of the deflection member 50 depending on the refractive power of the subject's eye E. For example, the main controller 101 selectively arranges a plurality of deflection members with deflection surfaces of different sizes in the optical path of the return light from the subject's eye E shown in FIG. 1 etc. In this way, by optimizing the size of the deflection surface of the deflection member 50 depending on the refractive power of the subject's eye E, it becomes possible to miniaturize the optical system while maintaining the effect of deflecting all of the fundus-reflected light out of the return light from the subject's eye E.

[0107] In some embodiments or their modifications, the corneal reflection light removal size of the black dot plate 60 that blocks or reflects corneal reflection light is configured to be changeable. For example, the main controller 101 may be able to change the corneal reflection light removal size of the black dot plate 60 depending on the refractive power of the subject's eye E. For example, the main controller 101 selectively places a plurality of black dot plates with different corneal reflection light removal sizes in the optical path of the light returned from the subject's eye E shown in FIG. 1 etc. In this way, by optimizing the corneal reflection light removal size of the black dot plate 60 depending on the refractive power of the subject's eye E, it is possible to miniaturize the optical system while maintaining the effect of removing all of the corneal reflection light from the light returned from the subject's eye E.

[0108] In some embodiments or their modifications, the corneal reflected light removal size of the black dot plate 60 that blocks or reflects the corneal reflected light is changed in accordance with the size of the deflection surface of the deflection member 50. For example, the main control unit 101 changes the corneal reflected light removal size of the black dot plate 60 and the size of the deflection surface of the deflection member 50 in conjunction with each other according to the refractive power of the eye E to be examined.

[0109] [Effect] An ophthalmologic apparatus according to an embodiment will be described.

[0110] A first aspect of some embodiments is an ophthalmic apparatus including a projection optical system (10), a light-receiving optical system (20), and a deflection member (50). The projection optical system projects light onto a fundus (Ef) of an eye (E) to be examined. The light-receiving optical system receives light returning from the eye to be examined. The deflection member can be arranged at a position that is approximately optically conjugate with the fundus (fundus conjugate position P), and deflects the returning light and guides it to the light-receiving optical system.

[0111] According to this aspect, in an ophthalmologic apparatus configured to project light onto the fundus of a subject's eye using a projection optical system, a deflector disposed at a position substantially optically conjugate with the fundus deflects the return light from the subject's eye toward the light-receiving optical system. This makes it possible to remove most of the noise light, including corneal reflection light, while guiding the return light from the subject's eye with an improved S / N ratio of the fundus reflection light to the light-receiving optical system. Therefore, it is possible to remove noise light, including corneal reflection light, with a simple configuration.

[0112] A second aspect of some embodiments is the first aspect of the present invention, which includes an optical scanner (40) that can be positioned at a position that is approximately optically conjugate with the iris of the subject's eye (iris conjugate position Q). The projection optical system projects light onto the fundus via the optical scanner. The light receiving optical system receives returning light via the optical scanner. The deflection member can be positioned at a position that is approximately optically conjugate with the fundus between the optical scanner and the light receiving optical system.

[0113] According to this aspect, when the fundus is scanned using an optical scanner, it is possible to remove most of the noise light, including the corneal reflected light, while guiding the returned light from the test eye with an improved S / N ratio of the fundus reflected light to the light receiving optical system.

[0114] A third aspect of some embodiments includes a first light focusing member (relay lens 51) disposed between the optical scanner and the deflection member in the second aspect. The deflection member is disposed at or near the back focal position of the first light focusing member.

[0115] According to this aspect, it is possible to deflect approximately parallel light using the optical scanner while focusing (converging) the returning light onto the deflection surface of the deflection member, thereby making it possible to reduce the size of the deflection surface of the deflection member.

[0116] A fourth aspect of some embodiments is the second or third aspect, further comprising a concave mirror (ellipsoidal mirror 70) having a concave reflecting surface and disposed between the optical scanner and the subject's eye. The concave mirror guides light deflected by the optical scanner to the fundus and guides returning light from the subject's eye to the optical scanner.

[0117] According to this aspect, it is possible to scan the fundus of the test eye over a wide angle while removing most of the noise light, including corneal reflected light, and guide the returned light from the test eye with an improved S / N ratio of the fundus reflected light to the light receiving optical system.

[0118] A fifth aspect of some embodiments is the fourth aspect, which further includes a reflective member (flat mirror 71) disposed between the optical scanner and the concave mirror and having a reflective surface disposed opposite the reflective surface of the concave mirror. The reflective member guides the light deflected by the optical scanner to the reflective surface of the concave mirror and also guides the returning light from the reflective surface of the concave mirror to the optical scanner.

[0119] According to this embodiment, it is possible to remove most of the noise light, including the corneal reflected light, while ensuring space for positioning the subject's face, and to guide the returned light from the subject's eye with an improved S / N ratio of the fundus reflected light to the light receiving optical system.

[0120] In a sixth aspect of some embodiments, in the fourth or fifth aspect, the concave mirror is an ellipsoidal mirror (70) having an ellipsoidal reflecting surface. The optical scanner is placed at or near a first focal position (focal position F1') of the reflecting surface of the ellipsoidal mirror. The iris of the subject's eye can be placed at or near a second focal position (focal position F2) of the reflecting surface of the ellipsoidal mirror.

[0121] According to this aspect, it is possible to use an ellipsoidal mirror to scan the fundus of the test eye at a wide angle with high precision and reduced aberration, while removing most of the noise light including corneal reflected light, and guiding the returned light from the test eye with an improved S / N ratio of the fundus reflected light to the light receiving optical system.

[0122] A seventh aspect of some embodiments is any of the first to sixth aspects, further comprising a black dot plate (60) disposed between the deflector and the light receiving optical system.

[0123] According to this embodiment, after removing most of the noise light including the corneal reflected light by the deflection member, it is possible to remove the remaining components of the corneal reflected light by the black spot plate, thereby further improving the S / N ratio of the fundus reflected light.

[0124] In some eighth aspects of the present invention, the seventh aspect of the present invention further includes a second light focusing member (relay lens 52) disposed between the deflector and the black dot plate. The deflector is disposed at or near the front focal position of the second light focusing member.

[0125] According to this aspect, the second light focusing member can mask the corneal reflected light while reducing the proportion of fundus reflected light removed by the black dot plate at positions where the beam diameter of the returning light is large, thereby further improving the S / N ratio of the fundus reflected light.

[0126] In a ninth aspect of some embodiments, in the seventh or eighth aspect, the size of the black dot plate for removing corneal reflected light is larger than the size of the deflection surface of the deflection member.

[0127] According to this embodiment, the size of the black dot plate can be minimized to remove corneal reflected light, thereby enabling the optical system to be made compact.

[0128] In a tenth aspect of some embodiments, in the ninth aspect, the size of the deflection surface is configured to be variable.

[0129] According to this aspect, by using a deflecting member having a deflecting surface of an optimal size depending on the state of the subject's eye, it is possible to achieve a compact optical system while maintaining the effect of deflecting all of the fundus reflected light. For example, it is possible to use a deflecting member having a deflecting surface of an optimal size depending on the refractive power of the subject's eye.

[0130] In an eleventh aspect of some embodiments, in the ninth or tenth aspect, the corneal reflection removal size is configured to be changeable.

[0131] According to this aspect, by using a black dot plate having a size for eliminating corneal reflection that is optimal for the condition of the subject's eye, it is possible to miniaturize the optical system while maintaining the effect of eliminating all corneal reflection. For example, it is possible to use a black dot plate having a size for eliminating corneal reflection that is optimal for the refractive power of the subject's eye.

[0132] In a twelfth aspect of some embodiments, in any one of the ninth to eleventh aspects, the size of the corneal reflected light removal surface is changed in accordance with the size of the deflection surface.

[0133] According to this aspect, by using a deflection member having a deflection surface of an optimal size according to the condition of the subject's eye and a black dot plate of an optimal size for removing corneal reflected light, it is possible to achieve a compact optical system while maintaining the effect of deflecting all of the fundus reflected light and removing all of the corneal reflected light. For example, it is possible to use a deflection member having a deflection surface of an optimal size according to the refractive power of the subject's eye and a black dot plate of an optimal size for removing corneal reflected light.

[0134] <Other> The embodiment described above is merely one example for carrying out the present invention, and those who wish to carry out the present invention may make any modifications, omissions, additions, etc. within the scope of the gist of the present invention. [Explanation of symbols]

[0135] 1, 1a Ophthalmological equipment 10, 10a projection optical system 20, 20a Light receiving optical system 30 Optical path coupling member 40 Optical Scanner 50 Deflection member 51, 52 Relay lenses 60 black dot plate 70 Ellipsoidal Mirror 71 Plane Mirror 100 control section 101 Main control unit 102 Storage section E. Examined eye Ef fundus F1, F1', F2 focal position P Fundus conjugate position Q Iris conjugate position

Claims

1. a projection optical system that projects light onto the fundus of the subject's eye; a light receiving optical system that receives return light from the subject's eye; a deflection member that can be arranged at a position that is optically conjugate with the fundus, and that deflects the returning light and guides it to the light-receiving optical system; Including, An ophthalmologic apparatus, wherein the size of the deflecting surface of the deflecting member is changeable depending on the refractive power of the eye to be examined.

2. an optical scanner that can be arranged at a position that is optically conjugate with the iris of the subject's eye; the projection optical system projects light onto the fundus via the optical scanner; the light receiving optical system receives the returned light via the optical scanner; The deflection member can be disposed at a position between the optical scanner and the light receiving optical system that is approximately optically conjugate with the fundus.

2. An ophthalmic apparatus according to claim 1.

3. a first light focusing member disposed between the optical scanner and the deflection member; The deflector is disposed at or near the rear focal position of the first light focusing member.

3. An ophthalmic apparatus according to claim 2.

4. a concave mirror having a concave reflecting surface and disposed between the optical scanner and the eye to be examined; The concave mirror guides the light deflected by the optical scanner to the fundus and guides the return light from the subject's eye to the optical scanner.

4. An ophthalmic apparatus according to claim 2 or 3.

5. a reflecting member disposed between the optical scanner and the concave mirror and having a reflecting surface disposed so as to face the reflecting surface of the concave mirror; The reflecting member guides the light deflected by the optical scanner to the reflecting surface of the concave mirror, and also guides the returning light from the reflecting surface of the concave mirror to the optical scanner.

5. An ophthalmic apparatus according to claim 4.

6. the concave mirror is an ellipsoidal mirror having an ellipsoidal reflecting surface, the optical scanner is disposed at or near a first focal position of the reflecting surface of the ellipsoidal mirror, The iris of the subject's eye can be positioned at or near the second focal position of the reflecting surface of the ellipsoidal mirror.

6. An ophthalmic apparatus according to claim 4 or claim 5.

7. and a black spot plate disposed between the deflector and the light receiving optical system.

7. The ophthalmic apparatus according to claim 1, wherein the ophthalmic apparatus is a microscope.

8. a second light focusing member disposed between the deflector and the black dot plate; The deflector is disposed at or near the front focal position of the second light focusing member.

8. An ophthalmic apparatus according to claim 7.

9. The size of the black dot plate for removing corneal reflected light is larger than the size of the deflection surface of the deflection member.

9. An ophthalmic apparatus according to claim 7 or 8.

10. The corneal reflection light removal size is configured to be changeable.

10. An ophthalmic apparatus according to claim 9.

11. The corneal reflection light removal size is changed in accordance with the size of the deflection surface.

11. An ophthalmic apparatus according to claim 9 or 10.

Images