Ophthalmologic apparatus and ophthalmology imaging method

Abstract

SOLUTION: The ophthalmic optical system is configured to apply an angular scanning light ray to an eye. M=|ωout / ωin| is defined, where ωin represents an angle between an incident light ray to the ophthalmic optical system and an optical axis of the ophthalmic optical system, and ωout represents an angle between an emitted light ray from the ophthalmic optical system toward the eye and the optical axis, M is defined as M=|ωout / ωin|, Mpar represents M when an incident light ray is a paraxial light beam, and Mmax represents M when an incident light ray is maximum angle light ray of ωin. The ophthalmic optical system satisfies a conditional expression Mpar<Mmax.EFFECT: This configuration allows SLO imaging in an ultra-wide-angle field, as well as allows OCT imaging in every area in an ultra-wide angle of view.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The technology of the present disclosure relates to an ophthalmic apparatus and an ophthalmic imaging method. [Background technology]

[0002] Patent Documents 1, 2, and 3 disclose devices for photographing an eye to be examined using a scanning laser ophthalmoscope and an optical coherence tomography. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US Patent Application Publication No. 2015 / 0216408 [Patent Document 2] US Patent Application Publication No. 2016 / 0150953 [Patent Document 3] As described in U.S. Patent Application Publication No. 2014 / 0320813, for convenience, a scanning laser ophthalmoscope will be referred to as "SLO," and optical coherence tomography will be referred to as "OCT." Summary of the Invention

[0004] The first aspect of the technology of the present disclosure is a light source for providing light; an ophthalmic optical system configured to irradiate the light from the light source onto the subject's eye; a scanning unit that is arranged at a position conjugate with a position corresponding to a pupil position of the subject's eye with respect to the ophthalmic optical system, and that scans the light from the light source angularly to scan the light irradiated onto the subject's eye; a light receiving unit that receives reflected light from the subject's eye via the ophthalmic optical system and the scanning unit; an image processing unit that forms an image of the subject's eye based on information from the light receiving unit and information from the scanning unit; Including, The ophthalmic optical system comprises: an angle formed between an incident light ray incident on the ophthalmic optical system from the light source side by the scanning unit and an optical axis of the ophthalmic optical system is defined as ωin; an angle formed between the optical axis and an emergent light ray emitted from the ophthalmic optical system toward the eye to be examined is defined as ωout; In the ophthalmic optical system, M is defined as M=|ωout / ωin|, M when the incident ray is a paraxial ray is Mpar, and When the incident light ray is the maximum angle light ray of ωin, M is Mmax. Mpar <Mmax The value of M is distributed so as to satisfy the conditional expression The image processing unit corrects data relating to the light reception result of the light receiving unit based on the distribution of the value of M related to the incident angle ωin scanned by the scanning unit. It is an ophthalmic device.

[0005] The ophthalmic optical system may have a distribution in which M increases as ωin increases within the range from Mpar to Mmax. The ophthalmic apparatus further includes a storage device that stores a change characteristic of the value of M depending on the angle ωout on the subject's eye side by the ophthalmic optical system, The image processing unit can correct data relating to the light receiving result of the light receiving unit based on the change characteristic of the value of M depending on the angle ωout stored in the storage device. A second aspect of the technology of the present disclosure is a light source for providing light; an ophthalmic optical system configured to irradiate the light from the light source onto the subject's eye; a scanning unit that is arranged at a position conjugate with a position corresponding to a pupil position of the subject's eye with respect to the ophthalmic optical system, and that scans the light from the light source angularly to scan the light irradiated onto the subject's eye; a light receiving unit that receives reflected light from the subject's eye via the ophthalmic optical system and the scanning unit; an image processing unit that forms an image of the subject's eye based on information from the light receiving unit and information from the scanning unit; Including, The ophthalmic optical system comprises: an angle formed between an incident light ray incident on the ophthalmic optical system from the light source side by the scanning unit and an optical axis of the ophthalmic optical system is defined as ωin; an angle formed between the optical axis and an emergent light ray emitted from the ophthalmic optical system toward the eye to be examined is defined as ωout; In the ophthalmic optical system, M is defined as M=|ωout / ωin|, M when the incident ray is a paraxial ray is Mpar, and When the incident light ray is the maximum angle light ray of ωin, M is Mmax. Mpar <Mmax The value of M is distributed so as to satisfy the conditional expression An ophthalmic imaging method for an ophthalmic device, comprising: setting a scanning range of the scanning unit at an angle ωin; inputting a change characteristic of the value of M due to the angle ωout on the subject's eye side by the ophthalmic optical system; correcting data relating to the light receiving results of the light receiving unit based on a change characteristic indicating the distribution of the value of M, and forming an image of the subject's eye corresponding to the scanning range of the angle ωin by the scanning unit; The present invention relates to an ophthalmologic imaging method including:

[0006] the ophthalmic apparatus further includes a storage device that stores a change characteristic of the value of M depending on an angle ωout on the subject's eye side by the ophthalmic optical system, The step of inputting the change characteristic of the value of M can use the change characteristic of the value of M stored in the storage device. The ophthalmic optical system may be configured such that M increases as ωin increases within the range from Mpar to Mmax. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a schematic diagram showing an example of the overall configuration of an ophthalmologic apparatus. [Figure 2] FIG. 1 is a conceptual diagram showing an example of a schematic configuration of a wide-angle optical system included in an ophthalmic apparatus. [Figure 3] FIG. 1 is a diagram showing an example of a composite objective lens system for SLO and OCT as a wide-angle optical system. [Figure 4] FIG. 4 is a diagram for explaining angular magnification. [Figure 5] FIG. 4 is a diagram for explaining angular magnification. [Figure 6A] FIG. 10 is a conceptual diagram showing the configuration of a modified example of a compound objective lens system. [Figure 6B] FIG. 10 is a conceptual diagram showing the configuration of another modified example of the compound objective lens system. [Figure 7] 3 is a diagram for explaining the incident angle ωin and the exit angle ωout of scanning light in an objective lens system. [Figure 8] FIG. 2 is a diagram showing an example of the relationship between ωin and ωout of an objective lens system. [Figure 9] FIG. 10 is a diagram showing an example of the relationship between ωout and M of the objective lens system. [Figure 10] 1 is a conceptual diagram showing a light beam with a maximum angle of view and a paraxial light beam that are incident on a pupil plane of a subject's eye via an objective lens system from a scanner. [Figure 11] 10A and 10B are diagrams showing examples of cross-sectional shapes of light beams at minimum and maximum angles on the pupil plane of the eye to be examined. [Figure 12] FIG. 10 is a diagram showing an example of the relationship between ωout and Pmax / Pmin of an objective lens system. [Figure 13] FIG. 1 is a diagram showing the configuration of an objective lens system according to Example 1-1. [Figure 14] FIG. 10 is a diagram showing the relationship between ωout and M of the objective lens system of Example 1-1. [Figure 15] FIG. 10 is a graph showing the relationship between ωout and Pmax / Pmin of the objective lens system of Example 1-1. [Figure 16] FIG. 10 is a diagram showing the configuration of an objective lens system according to Example 1-2. [Figure 17] FIG. 10 is a diagram showing the relationship between ωout and M of the objective lens system of Example 1-2. [Figure 18] FIG. 10 is a graph showing the relationship between ωout and Pmax / Pmin of the objective lens system of Example 1-2. [Figure 19] FIG. 2 is a diagram showing the configuration of an objective lens system according to Example 2-1. [Figure 20]FIG. 10 is a diagram showing the relationship between ωout and M of the objective lens system of Example 2-1. [Figure 21] FIG. 10 is a graph showing the relationship between ωout and Pmax / Pmin of the objective lens system of Example 2-1. [Figure 22] FIG. 2 is a diagram showing the configuration of an objective lens system according to Example 2-2. [Figure 23] FIG. 10 is a diagram showing the relationship between ωout and M of the objective lens system of Example 2-2. [Figure 24] FIG. 10 is a graph showing the relationship between ωout and Pmax / Pmin of the objective lens system of Example 2-2. [Figure 25] FIG. 3 is a diagram showing the configuration of an objective lens system according to Example 3-1. [Figure 26] FIG. 10 is a diagram showing the relationship between ωout and M of the objective lens system of Example 3-1. [Figure 27] FIG. 10 is a diagram showing the relationship between ωout and Pmax / Pmin of the objective lens system of Example 3-1. [Figure 28] FIG. 3 is a diagram showing the configuration of an objective lens system according to Example 3-2. [Figure 29] FIG. 10 is a diagram showing the relationship between ωout and M of the objective lens system of Example 3-2. [Figure 30] FIG. 10 is a graph showing the relationship between ωout and Pmax / Pmin of the objective lens system of Example 3-2. [Figure 31] FIG. 4 is a diagram showing the configuration of an objective lens system according to Example 4-1. [Figure 32] FIG. 4 is a diagram showing the relationship between ωout and M of the objective lens system of Example 4-1. [Figure 33] FIG. 4 is a graph showing the relationship between ωout and Pmax / Pmin of the objective lens system of Example 4-1. [Figure 34] FIG. 5 is a diagram showing the configuration of an objective lens system according to Example 5-1. [Figure 35] FIG. 6 is a diagram showing the configuration of an objective lens system according to Example 6-1. [Figure 36] FIG. 7 is a diagram showing the configuration of an objective lens system according to Example 7-1. [Figure 37] FIG. 8 is a diagram showing the configuration of an objective lens system according to Example 8-1. [Figure 38] FIG. 9 is a diagram showing the configuration of an objective lens system according to Example 9-1. [Figure 39] FIG. 10 is a diagram showing the configuration of an objective lens system according to Example 10-1. [Figure 40] FIG. 11 is a diagram showing the configuration of an objective lens system according to Example 11-1. [Figure 41] FIG. 10 is a cross-sectional view showing the configuration of another embodiment of the imaging optical system. [Figure 42] FIG. 10 is a perspective view showing the configuration of still another embodiment of the imaging optical system. [Figure 43] 10 is a flowchart showing the operation of the image processing device. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, the embodiments will be described in detail with reference to the drawings.

[0009] First, an example of the configuration of an ophthalmic apparatus 110 will be described with reference to Fig. 1. The ophthalmic apparatus 110 includes an imaging device 14 and a control device 16. The imaging device 14 is equipped with an SLO unit 18 and an OCT unit 20, and acquires a fundus image of the fundus of the subject's eye 12. Hereinafter, the image acquired by the SLO unit 18 will be referred to as an SLO image. Also, the image acquired by the OCT unit 20 will be referred to as an OCT image.

[0010] The control device 16 is realized by a computer having a central processing unit (CPU) 16A, random access memory (RAM) 16B, read-only memory (ROM) 16C, and an input / output (I / O) port 16D.

[0011] The control device 16 includes an input / display device 16E connected to the CPU 16A via an I / O port 16D. The input / display device 16E has a graphic user interface that displays an image of the subject's eye 12 and receives various instructions from the user. An example of the graphic user interface is a touch panel display.

[0012] The control device 16 also includes an image processing device 17 connected to the I / O port 16D. The image processing device 17 generates an image of the subject's eye 12 based on data obtained by the photographing device 14. The control device 16 may be configured to be connected to a network via a communication interface (not shown).

[0013] The imaging device 14 operates under the control of the control device 16. The imaging device 14 includes an SLO unit 18, an imaging optical system 19, and an OCT unit 20. The imaging optical system 19 includes a first optical scanner 22, a second optical scanner 24, and a wide-angle optical system 30. The wide-angle optical system 30 includes an objective lens system (not shown in FIG. 1 ) having a common lens group 28, and a combining unit 26.

[0014] The first optical scanner 22 performs two-dimensional scanning in the X and Y directions with the light emitted from the SLO unit 18. The second optical scanner 24 performs two-dimensional scanning in the X and Y directions with the light emitted from the OCT unit 20. The first optical scanner 22 and the second optical scanner 24 may be optical elements that can deflect a light beam, such as a polygon mirror or a galvanometer mirror. Alternatively, a combination of these may be used.

[0015] In this specification, when the ophthalmic device 110 is installed on a horizontal plane, the horizontal direction is referred to as the "X direction," the direction perpendicular to the horizontal plane is referred to as the "Y direction," and the direction perpendicular to both the X direction and the Y direction is referred to as the "Z direction."

[0016] The imaging optical system 19 includes a wide-angle optical system 30. The wide-angle optical system 30 enables observation of the fundus over a wide FOV (Field of View) 12A. The FOV 12A indicates the range that can be imaged by the imaging device 14. The FOV 12A can be expressed as a field of view. In this embodiment, the field of view can be defined by an internal illumination angle and an external illumination angle. The external illumination angle is the illumination angle of the light beam irradiated from the ophthalmic device 110 to the subject's eye 12, determined with the pupil 27 as the reference. The internal illumination angle is the illumination angle of the light beam irradiated to the fundus, determined with the center O of the eyeball as the reference. The external illumination angle and the internal illumination angle correspond to each other. For example, if the external illumination angle is 120 degrees, the internal illumination angle corresponds to approximately 160 degrees.

[0017] As shown in FIG. 1 , the SLO system is realized by a control device 16, an SLO unit 18, and an imaging optical system 19. The SLO system includes a wide-angle optical system 30, enabling fundus imaging with a wide FOV 12A. The SLO unit 18 includes a light source 18A, a detection element 18B, and a beam splitter 18C. The detection element 18B is an example of a light receiving unit according to the technology of the present disclosure. Light emitted from the light source 18A passes through the beam splitter 18C and enters the imaging optical system 19. The light entering the imaging optical system 19 is scanned in the X and Y directions by the first optical scanner 22. The scanned light passes through the wide-angle optical system 30 and the pupil 27 and is irradiated onto the fundus. The reflected light from the fundus passes through the wide-angle optical system 30 and the first optical scanner 22 and enters the SLO unit 18. The reflected light entering the SLO unit is reflected by the beam splitter 18C and received by the detection element 18B. The image processing device 17 generates an SLO image based on the signal detected by the detection element 18B.

[0018] As shown in FIG. 1, the OCT system is realized by a control device 16, an OCT unit 20, and an imaging optical system 19. Since the OCT system includes a wide-angle optical system 30, it enables fundus imaging with a wide FOV 12A. The OCT unit 20 includes a light source 20A, a detection element 20B, an optical coupler 20C, an optical coupler 20F, a reference optical system 20D, and a collimating lens 20E. Note that the detection element 20B is an example of a light receiving unit according to the technology of the present disclosure. The light emitted from the light source 20A is branched by the optical coupler 20C. One of the branched lights is used as measurement light, which is made parallel by the collimating lens 20E and then incident on the imaging optical system 19. The measurement light is scanned in the X direction and the Y direction by the second optical scanner 24. The scanned light is irradiated onto the fundus via the wide-angle optical system 30 and the pupil 27. The measurement light reflected by the fundus is incident on the OCT unit 20 via the wide-angle optical system 30 and the second optical scanner 24. The other light branched by the optical coupler 20C is incident on the reference optical system 20D as reference light. The reference light and the measurement light reflected by the fundus interfere with each other at the optical coupler 20F to generate interference light. The interference light is received by the detection element 20B. The image processing device 17 generates an OCT image based on the signal detected by the detection element 20B. Note that as the OCT method, SD-OCT (Spectral-Domain OCT) or SS-OCT (Swept-Source OCT) may be used.

[0019] <Compound objective lens system for SLO and OCT> Next, referring to FIG. 2, the configuration of the wide-angle optical system 30 included in the imaging optical system 19 will be described. Hereinafter, the light emitted from the SLO unit 18 and incident on the imaging optical system 19 is referred to as "SLO light", and the light emitted from the OCT unit 20 and incident on the imaging optical system 19 is referred to as "OCT light". In the present embodiment, the SLO light and the OCT light incident on the imaging optical system 19 are configured to be substantially parallel light.

[0020] Fig. 2 is a conceptual diagram showing an example of a schematic configuration of the imaging optical system 19. As shown in Fig. 2, the wide-angle optical system 30 has a configuration in which an SLO objective lens system 31 used to acquire SLO images and an OCT objective lens system 32 used to acquire OCT images are combined by a combining unit 26. The SLO objective lens system 31 and the OCT objective lens system 32 are each an example of an ophthalmic optical system according to the technology of the present disclosure, an example of an ophthalmic objective lens according to the technology of the present disclosure, and an example of an objective lens according to the technology of the present disclosure.

[0021] The SLO objective lens system 31 is composed of a first lens group G1 and a third lens group G3. The OCT objective lens system 32 is composed of a second lens group G2 and a third lens group G3. The first lens group G1 is a lens group dedicated to SLO. The second lens group G2 is a lens group dedicated to OCT. The third lens group G3 is an example of the common lens group 28 shown in Figure 1. The SLO objective lens system 31 has an optical path that passes through the combining unit 26, and the combining unit 26 is located between the first lens group G1 and the third lens group G3. The combining unit 26 is also located in the optical path between the second lens group G2 and the third lens group G3, and the OCT objective lens system 32 has a bent optical path in which the optical path is bent by the combining unit 26. That is, the SLO objective lens system 31 and the OCT objective lens system 32 have a third lens group G3 as a common lens group 28 on the subject's eye side of the combining unit 26.

[0022] In this embodiment, the SLO light and the OCT light have different wavelengths, and a wavelength-dependent dichroic mirror is used as the combining unit 26. The combining unit 26 in Fig. 2 has a function of combining the optical path of the SLO light toward the subject's eye and the optical path of the OCT light toward the subject's eye. The combining unit 26 also has a function of separating the optical path of the reflected light based on the SLO light from the optical path of the reflected light based on the OCT light, with respect to light irradiated onto the subject's eye 12 and reflected by the subject's eye 12, and guiding the reflected light based on the SLO light to the first lens group G1 and the reflected light based on the OCT light to the second lens group G2.

[0023] 2, by using an element having light combining and light separating functions, such as a dichroic mirror, the SLO objective lens system 31 and the OCT objective lens system 32 share a lens group on the subject's eye side, thereby forming a composite objective lens system that combines the SLO objective lens system 31 and the OCT objective lens system 32. This makes it possible to obtain an ultra-wide-angle fundus image and an ultra-wide-angle tomographic image of the retina in the fundus portion with a single device.

[0024] The SLO light can be a single wavelength of visible light or multiple wavelengths of visible light. For example, three wavelengths of 450 nm, 520 nm, and 638 nm can be used as the SLO light to obtain a color SLO image. The OCT light can be infrared light with a wavelength of 800 to 1000 nm. Because the SLO light and the OCT light have different wavelengths, the SLO objective lens system 31 and the OCT objective lens system 32 are configured so that chromatic aberration occurring in the third lens group G3, which is closer to the subject's eye than the combining unit 26, is corrected in the first lens group G1 according to the wavelength of the SLO light, and in the second lens group G2 according to the wavelength of the OCT light.

[0025] The SLO objective lens system 31 is an afocal optical system and is configured to establish a conjugate relationship between the position of the first optical scanner 22 (the position of the scanning center of the first optical scanner 22) and the pupil position of the subject's eye 12. The OCT objective lens system 32 is also an afocal optical system and is configured to establish a conjugate relationship between the position of the second optical scanner 24 (the position of the scanning center of the second optical scanner 24) and the pupil position of the subject's eye 12. In this specification, the term "conjugate relationship" is not limited to a perfect conjugate relationship, but refers to a conjugate relationship that includes errors that are allowed in advance as manufacturing errors, errors associated with changes over time, and the like. In this specification, the term "afocal optical system" is not limited to a perfect afocal optical system, but refers to an afocal optical system that includes errors that are allowed in advance as manufacturing errors, errors associated with changes over time, and the like.

[0026] The operation of the imaging optical system 19 having the above configuration will be described. First, the operation related to SLO imaging will be described. The SLO light, which is a parallel beam entering the imaging optical system 19 from the SLO unit 18, is angularly scanned by the first optical scanner 22, such as a polygon mirror. The angularly scanned parallel SLO light passes through the first lens group G1, the combining unit 26, and the third lens group G3 in this order, and is projected as parallel light onto the pupil plane of the subject's eye 12 at a predetermined magnification, performing angular scanning with the pupil of the subject's eye 12 as the scanning center. This parallel light is focused by the subject's eye 12, and at the fundus of the subject's eye 12, the focused spot of the SLO light scans the fundus as illumination light. The reflected light obtained by reflecting this illumination light from the fundus passes through the pupil of the subject's eye 12, passes through the third lens group G3, the combining unit 26, and the first lens group G1 in this order, passes through the first optical scanner 22, and enters the SLO unit 18. The operation after the reflected light enters the SLO unit 18 is the same as that described with reference to FIG.

[0027] The operation of OCT imaging will now be described. The parallel OCT light incident on the imaging optical system 19 from the OCT unit 20 is angularly scanned by the second optical scanner 24, such as a galvanometer mirror. The angularly scanned parallel OCT light passes through the second lens group G2, is reflected by the combining unit 26, and then passes through the third lens group G3 to be projected as parallel light onto the pupil plane of the subject's eye 12 at a predetermined magnification, performing angular scanning with the pupil of the subject's eye 12 as the scanning center. This parallel light is focused by the subject's eye 12, and at the fundus of the subject's eye 12, a focused spot of the OCT light scans the fundus (retinal surface) and the inside of the retina as illumination light. The reflected light obtained by reflection of this OCT light from the fundus or inside the retina passes through the pupil of the subject's eye 12, passes through the third lens group G3, is reflected by the combining unit 26, passes through the second lens group G2, passes through the second optical scanner 24, and enters the OCT unit 20. The operation after the reflected light enters the OCT unit 20 is as described with reference to Figure 1. As mentioned above, the OCT objective lens system 32 is also an approximately afocal system like the SLO objective lens system 31. However, the beam diameter of the irradiated light is relatively large to obtain cross-sectional information of the fundus of the subject's eye 12, and it is necessary to accurately focus the light on the observation surface. Therefore, it is necessary to appropriately converge or diverge the parallel light beam depending on changes in the distance to the observation surface and the diopter of the subject's eye 12. However, even in this case, the afocal system is still the standard for the objective lens system.

[0028] 3 shows an example of the specific configuration of the first lens group G1, the second lens group G2, and the third lens group G3. As shown in the figure, the first lens group G1 includes, in order from the first optical scanner 22 side to the test eye side, a meniscus-shaped lens component (a cemented lens of lenses L11 and L12) with a convex surface facing the first optical scanner 22 side, a negative lens L13 with a concave surface facing the first optical scanner 22 side, a positive lens L14 with a convex surface facing the test eye side, and a positive lens L15. More specifically, the shape of the negative lens L13 is such that the absolute value of the radius of curvature of the lens surface facing the first optical scanner 22 is smaller than the absolute value of the radius of curvature of the lens surface facing the test eye side. Furthermore, the shape of the positive lens L14 is such that the absolute value of the radius of curvature of the lens surface facing the test eye side is smaller than the absolute value of the radius of curvature of the lens surface facing the first optical scanner 22 side. In this specification, the term "lens component" refers to a lens that has two interfaces with air on the optical axis, and one lens component refers to either a single lens or a set of cemented lenses formed by cementing together multiple lenses. The meniscus-shaped lens component in first lens group G1 is effective for correcting chromatic aberration when configured as a cemented lens as shown in the figure, but can be configured as a single lens when the wavelength range of light used is relatively narrow.

[0029] As an example, the second lens group G2 includes, in order from the second optical scanner 24 side to the test eye side, a meniscus-shaped lens component (a cemented lens of lenses L21 and L22) with a convex surface facing the second optical scanner 24 side, a negative lens L23 with a concave surface facing the second optical scanner 24 side, a positive lens L24 with a convex surface facing the test eye side, and a positive lens L25. More specifically, the shape of the negative lens L23 is such that the absolute value of the radius of curvature of the lens surface facing the second optical scanner 24 is smaller than the absolute value of the radius of curvature of the lens surface facing the test eye side. Furthermore, the shape of the positive lens L24 is such that the absolute value of the radius of curvature of the lens surface facing the test eye side is smaller than the absolute value of the radius of curvature of the lens surface facing the second optical scanner 24 side. The meniscus-shaped lens component of the second lens group G2 is effective for correcting chromatic aberration when it is a cemented lens as shown in the figure, but can be a single lens when the wavelength range of light used is relatively narrow.

[0030] The third lens group G3 is a common lens group 28 provided between the combining unit 26 and the test eye 12 and used in common for SLO and OCT. The third lens group G3 includes, in order from the combining unit 26 to the test eye, a positive lens L31 with a convex surface facing the test eye, a lens component formed by cementing a positive lens L32 with a convex surface facing the test eye and a negative lens L33, a lens component formed by cementing a positive lens L34 with a convex surface facing the test eye and a negative lens L35, and a positive meniscus lens L36 with a concave surface facing the test eye. While the third lens group G3 in this example includes two cemented lenses, it may also be configured to include only one cemented lens depending on the chromatic aberration correction requirements.

[0031] In this embodiment, the paraxial angular magnifications of the SLO objective lens system 31 and the OCT objective lens system 32 are suitably set in the configuration having the common lens group 28. Here, the paraxial angular magnification will be described with reference to FIGS. 4 and 5.

[0032] 4 and 5 show examples of an afocal optical system 40 consisting of k surfaces. In FIGS. 4 and 5, the left side is the object side and the right side is the image side. A parallel light beam incident on the afocal optical system 40 emerges as a parallel light beam even after passing through the afocal optical system 40. However, the angle that the incident parallel light beam makes with the optical axis AX on the object side of the afocal optical system 40 (called the incident angle ω) is generally different from the angle that the emerging parallel light beam makes with the optical axis AX on the image side of the afocal optical system 40 (called the exit angle ωk).

[0033] As shown in Figure 5, assume that an arbitrary paraxial ray emitted from an axial object point located at a distance s1 on the object side from the first surface 401 of an afocal optical system 40 consisting of k surfaces passes through the afocal optical system 40 and intersects with the optical axis at a point sk' on the image side from the final surface, the kth surface 40k. The heights at which this paraxial ray intersects with the first surface 401 and the kth surface 40k are respectively denoted by h1 and hk, the angles it makes with the optical axis on the object side and the image side are respectively denoted by u1 and uk', and the size of the object and the size of its corresponding image are respectively denoted by y1 and yk'. For simplicity of explanation, the refractive index of the media before and after the afocal optical system is assumed to be 1. According to the Helmholtz-Lagrange invariant, u1·y1=uk'·yk' and u1=h1 / s1, uk'=hk / sk' h1·(y1 / s1)=hk·(yk' / sk') where ω≡y1 / s1, ωk≡yk' / sk' Then, when s1→-∞, sk'→∞. In this case, Mpar is defined as follows: Mpar≡ωk / ω=(h1 / hk) s1→-∞ Mpar is the angular magnification in the paraxial region, that is, the paraxial angular magnification. As is clear from the above explanation, when a paraxial ray parallel to the optical axis is incident on an afocal optical system, the paraxial ray remains parallel to the optical axis even after passing through the afocal optical system, and in this case, the ratio h1 / hk of the heights from the optical axis of the paraxial ray on the object side to the paraxial ray on the image side is taken to be the paraxial angular magnification of the afocal optical system. In other words, the paraxial angular magnification Mpar is a constant of the optical system that is unrelated to the angle of incidence ω. As is well known in the field of optics, lateral magnification is the reciprocal of angular magnification, so if the paraxial lateral magnification is βpar, then βpar=1 / Mpar is.

[0034] Here, M1 is the paraxial angular magnification of the optical system that establishes a conjugate relationship between the first optical scanner 22 and the pupil of the subject's eye 12, and M2 is the paraxial angular magnification of the optical system that establishes a conjugate relationship between the second optical scanner 24 and the pupil of the subject's eye 12. That is, in the configuration shown in Fig. 2, when M1 is the paraxial angular magnification of the SLO objective lens system 31 from the first optical scanner 22 to the subject's eye 12 and M2 is the paraxial angular magnification of the OCT objective lens system 32 from the second optical scanner 24 to the subject's eye 12, the configuration is such that the following conditional formula (1) is satisfied. |M1|<|M2| (1)

[0035] This configuration enables SLO imaging with an ultra-wide field of view (UWF) and OCT imaging of the entire area with an ultra-wide field of view. In one example of how the ophthalmologic apparatus is used, first, an image of a wide area, approximately the entire imageable area 12A of the subject's eye 12, is captured by high-speed scanning using SLO light at 0.5 seconds or less. Then, a narrow area, such as a lesion, is captured by OCT imaging using OCT light to obtain cross-sectional shape information. In this type of usage, a high scanning speed is required for at least one of the X- and Y-direction scans of the first optical scanner 22 for SLO imaging, but a similarly high scanning speed is not required for the second optical scanner 24 for OCT imaging. Therefore, specifically, it is practical to use a polygon mirror for at least one of the X- and Y-direction scans of the first optical scanner 22 for SLO imaging and a galvanometer mirror for the second optical scanner 24 for OCT imaging. If the maximum scan angle at which the SLO light can be scanned in the scanning direction using a polygon mirror as the first optical scanner 22 for SLO is θ1 and the maximum scan angle at which the second optical scanner 24 can scan with the OCT light is θ2, then due to the above circumstances, the maximum scan angle θ2 of the second optical scanner 24 for OCT is smaller than the maximum scan angle θ1 of the first optical scanner 22 for SLO, and θ2<θ1 holds. In other words, the scan angle range of the second optical scanner 24 is smaller than the scan angle range of the first optical scanner 22.

[0036] On the other hand, when considering the imageable area, although the area imaged by OCT imaging is small, it is not possible to identify the area where a lesion or the like occurs, so it is desirable that OCT imaging be possible in any part of the area imaged by SLO imaging. In other words, it is desirable that the area where OCT imaging is possible is the same as the area where SLO imaging is possible. In other words, if the external irradiation angle possible in SLO imaging is Θ1 and the external irradiation angle possible in OCT imaging is Θ2, it is desirable that Θ1 = Θ2.

[0037] By satisfying the above conditional expression (1), even when scanners with different scanning angles are used for SLO imaging and OCT imaging and θ2<θ1 holds, it is possible to make θ1=θ2.

[0038] More specifically, it is preferable to set the range of the paraxial angular magnification M1 of the SLO objective lens system 31 so as to satisfy the following conditional expression (2): Furthermore, it is preferable to set the range of the paraxial angular magnification M2 of the OCT objective lens system 32 so as to satisfy the following conditional expression (3): 1.5<|M1|<3.5 (2) 2.5<|M2|<5 (3)

[0039] A configuration that satisfies conditional expressions (2) and (3) is effective when the external illumination angle is wider than 100 degrees. Furthermore, a configuration that satisfies conditional expressions (2) and (3) is even more effective when an internal illumination angle of about 180 degrees or more is required due to ultra-wide-angle light beam scanning, known as UWF, in which the external illumination angle is wider than 120 degrees.

[0040] Furthermore, since the paraxial lateral magnification is the reciprocal of the paraxial angular magnification as described above, if the paraxial lateral magnification of the SLO objective lens system 31 from the first optical scanner 22 to the subject's eye 12 is β1 and the paraxial lateral magnification of the OCT objective lens system 32 from the second optical scanner 24 to the subject's eye 12 is β2, then the following conditional formula (4) is satisfied. Note that β1 here refers to the paraxial lateral magnification of the SLO objective lens system 31 when the scanning center of the first optical scanner 22 is the object point and the pupil position of the subject's eye 12 is the image point, and β2 refers to the paraxial lateral magnification of the OCT objective lens system 32 when the scanning center of the second optical scanner 24 is the object point and the pupil position of the subject's eye 12 is the image point. |β2|<|β1| (4)

[0041] Furthermore, paraxial lateral magnification can be considered as the ratio between the diameter of the incident light beam and the diameter of the exiting light beam when a collimated light beam parallel to the optical axis enters and exits the objective lens system. When collimated light beams of SLO light and OCT light parallel to the optical axis enter the objective lens system, the diameter of the incident light beam for SLO light is φin(SLO), the diameter of the exiting light beam is φout(SLO), and similarly the diameter of the incident light beam for OCT light is φin(OCT), and the diameter of the exiting light beam is φout(OCT), then β1=φout(SLO) / φin(SLO) β2=φout(OCT) / φin(OCT) Therefore, it can be seen from conditional formula (4) that when a collimated light beam parallel to the optical axis is incident on the objective lens system, the change in the light beam diameter caused by the objective lens system is smaller in the OCT objective lens system 32 than in the SLO objective lens system 31.

[0042] More specifically, it is preferable to set the range of β1 so as to satisfy the following conditional expression (5): Moreover, it is preferable to set the range of β2 so as to satisfy the following conditional expression (6). 0.25<|β1|<0.7 (5) 0.2<|β2|<0.4 (6)

[0043] A configuration that satisfies conditional expressions (5) and (6) is effective when the external illumination angle is wider than 100 degrees. Furthermore, a configuration that satisfies conditional expressions (5) and (6) is even more effective when an internal illumination angle of approximately 180 degrees or more is required due to ultra-wide-angle light beam scanning (UWF), where the external illumination angle is wider than 120 degrees. It is more preferable that the lower limit of conditional expression (5) be 0.28 and the upper limit be 0.67.

[0044] In the typical use of the ophthalmologic apparatus described above, the initial SLO imaging requires high-speed scanning using a polygon mirror or the like in at least one of the X- and Y-direction scans. In contrast, the scanning area in OCT imaging is relatively narrow, and the scanning speed is not as high as that required for SLO imaging. Therefore, the scanning speed at which the second optical scanner 24 scans with the OCT light in at least one of the X- and Y-direction scans is configured to be slower than the scanning speed at which the first optical scanner 22 scans with the SLO light. Note that the scanning speed here refers to the scanning time per unit area. SLO imaging requires high-speed scanning of the entire fundus imaging area with an ultra-wide angle (UWF), and the maximum scanning angle of the first optical scanner 22 for SLO is determined by the fundus imaging area. Meanwhile, OCT imaging scans a limited partial area requiring cross-sectional measurement. However, it is preferable that the maximum scanning angle of the second optical scanner 24 for OCT be configured to satisfy the relationship of the above conditional formula so that measurement can be performed on each partial area of ​​the entire fundus imaging area with an ultra-wide angle (UWF), similar to SLO imaging.

[0045] It is preferable that the photographic optical system 19, whose scanning speed is set as described above, is also configured to satisfy the above conditional expression (1). It is also preferable that at least one of the conditional expressions (2) and (3) is set to be satisfied. Similarly, it is preferable that the photographic optical system 19, whose scanning speed is set as described above, is configured to satisfy the above conditional expression (4). It is also preferable that at least one of the conditional expressions (5) and (6) is set to be satisfied.

[0046] The configuration according to the above conditional expressions (2), (3), (5), and (6) is not limited to the case where the wide-angle optical system 30 has a composite objective lens system of SLO and OCT, but is also effective when the SLO objective lens system 31 and the OCT objective lens system 32 are configured separately. Therefore, as a UWF objective lens, it is preferable that the paraxial angular magnification is greater than 1.5 due to the conditions shown in the above conditional expressions (2) and (3), and from a practical standpoint, it is advantageous that it is greater than 1.8.

[0047] In the above-described configuration, the third lens group G3 serving as the common lens group 28 primarily corrects pupil aberrations due to the nearly afocal system that forms a conjugate relationship between the pupil of the subject's eye 12 and the scanner, which is a basic function of both the SLO objective and the OCT objective. The first lens group G1, in combination with the third lens group G3, ensures the above-described magnification relationship required for the SLO objective system 31 and also corrects chromatic aberrations. The second lens group G2, in combination with the third lens group G3, also ensures the above-described magnification relationship required for the OCT objective system 32 and also corrects chromatic aberrations. While this lens configuration is suitable for an ultra-wide-angle objective system with an external illumination angle exceeding 120 degrees, it goes without saying that a simpler lens configuration is possible for a smaller angle of view.

[0048] 2, both the SLO objective lens system 31 and the OCT objective lens system 32 have lens groups on the scanner side (i.e., on the light source side) of the combining unit 26, but by appropriately designing the common lens group 28, it is also possible to configure either the SLO objective lens system 31 or the OCT objective lens system 32 so that it does not have a lens group on the light source side, i.e., on the scanner side, of the combining unit 26. Figures 6A and 6B show conceptual diagrams of a first modified example and a second modified example of a compound objective lens system, respectively.

[0049] In the configuration shown in FIG. 6A , compared to the configuration in FIG. 2 , no lens group is disposed between the first optical scanner 22 for SLO and the combining unit 26. Instead, the third lens group G3 in FIG. 2 is replaced with a third lens group G3-1, and the second lens group G2 in FIG. 2 is replaced with a second lens group G2-1. In the configuration in FIG. 6A , the third lens group G3-1 corresponds to the common lens group 28, the SLO objective lens system 31 is composed only of the third lens group G3-1, and the OCT objective lens system 32 is composed of the second lens group G2-1 and the third lens group G3-1. In this configuration, the third lens group G3-1 is subjected to aberration correction in the visible light range for SLO. Furthermore, the second lens group G2-1 in the OCT objective lens system 32, when combined with the third lens group G3-1, needs to be configured as a lens for aberration correction in the infrared range for OCT, and it is generally preferable that the second lens group G2-1 have a negative refractive power. Furthermore, in this modified example, taking into consideration the above-mentioned circumstances, the maximum scanning angle θ2 of the second optical scanner 24 for OCT is smaller than the maximum scanning angle θ1 of the first optical scanner 22 for SLO, and θ2<θ1.

[0050] Also, in the configuration shown in FIG. 6B, compared with the configuration of FIG. 2, no lens group is arranged between the second optical scanner 24 and the combining unit 26. The third lens group G3 in FIG. 2 is changed to the third lens group G3-2, and the first lens group G1 in FIG. 2 is changed to the first lens group G1-1. In the configuration of FIG. 6B, the third lens group G3-2 corresponds to the common lens group 28. The objective lens system 31 for SLO is composed of the first lens group G1-1 and the third lens group G3-2, and the objective lens system 32 for OCT is composed of only the third lens group G3-2. In this configuration, the third lens group G3-2 is corrected for aberration in the infrared light region for OCT. And the first lens group G1-1 in the objective lens system 31 for SLO needs to have a lens configuration for correcting aberration in the visible light region for SLO in the combined system with the third lens group G3-2, and basically it is preferable to have a configuration with positive refractive power. And even in this modified example, considering the above-mentioned circumstances, the maximum scanning angle θ2 of the second optical scanner 24 for OCT is smaller than the maximum scanning angle θ1 of the first optical scanner 22 for SLO, and θ2 < θ1.

[0051] Note that the shapes of the optical paths in FIGS. 2, 6A, and 6B are just examples. In the technology of the present disclosure, it is also possible to adopt optical paths with different shapes. For example, by appropriately setting the wavelength characteristics of the combining unit 26, a configuration in which the optical path of the objective lens system 31 for SLO is bent and the optical path of the objective lens system 32 for OCT is linear is also possible.

[0052] <Objective lens system for SLO or OCT> Next, the objective lens system used in the imaging optical system 19 will be described. Note that the embodiment described below is not limited to the case where the wide-angle optical system 30 has the compound objective lens system shown in FIGS. 2, 6A, and 6B, but can also be applied to the case where the SLO objective lens system 31 and the OCT objective lens system 32 are configured separately. Note that, for convenience of explanation, the SLO objective lens system 31 and the OCT objective lens system 32 will be simply referred to as "objective lens systems" below unless it is necessary to distinguish between them. Furthermore, the first optical scanner 22 and the second optical scanner 24 will be simply referred to as "scanners" below unless it is necessary to distinguish between them.

[0053] The SLO objective lens system and the OCT objective lens system, each having the above-described common lens group 28, are designed independently. In the following embodiment, the SLO objective lens system 31 and the OCT objective lens system 32 are each designed to have a suitable angular distribution of angular magnification. Here, the angular distribution of angular magnification will be described.

[0054] FIG. 7 shows an example of an objective lens system 300. The objective lens system 300 is a refractive optical system including eleven lenses L1 to L11. The objective lens system 300 is basically an afocal optical system. FIG. 7 also shows a scanning center position Ps where one reflecting surface of the scanner is located, and a pupil plane Pp of the subject's eye 12. The scanning center position Ps of the scanner and the position of the pupil plane Pp are configured to be optically conjugate by the objective lens system 300. The light beam incident from the scanner to the objective lens system 300 is approximately parallel light. FIG. 7 shows the state of the light beam at the maximum angle of view that is scanned by the scanner, passes through the objective lens system 300, and is incident on the pupil plane Pp.

[0055] 7, the angle formed between an incident light ray 44i incident on the objective lens system 300 from the scanner side and the optical axis AX of the objective lens system 300 is defined as ωin, and the angle formed between an exit light ray 44o emitted from the objective lens system 300 toward the eye to be examined and the optical axis AX is defined as ωout. M=|ωout / ωin| is defined. When M is Mpar when the incident light ray 44i is a paraxial ray and M is Mmax when the incident light ray 44i is the ray at the maximum angle of view, the following conditional expression (7) is satisfied. Mpar <Mmax (7)

[0056] Conditional expression (7) means that M for the ray at the maximum angle of view is greater than the angular magnification in the paraxial region. Satisfying conditional expression (7) facilitates achieving an aberration structure in which the angular distribution of angular magnification increases as the exit angle of peripheral rays increases. Configuring such an angular magnification distribution allows the scanner to achieve a larger maximum scanning angle, making it easier to obtain a larger external illumination angle for the objective lens system. This allows the viewing angle of the photographing optical system 19 at the fundus to be an angle that enables observation of a wide range of fundus regions, from the center to the periphery of the fundus.

[0057] Furthermore, it is preferable to satisfy the following conditional expression (8). 1.1×Mpar <Mmax (8) ωout is the angle of the light ray incident on the subject's eye 12 from the objective lens system 300. By satisfying conditional expression (8), the angle ωout of the light ray incident on the subject's eye 12 from the objective lens system 300 can be efficiently enlarged, making it easy to obtain a large external irradiation angle.

[0058] It is also preferable to satisfy the following conditional expression (9). Mmax<2×Mpar (9) By satisfying conditional expression (9), it becomes easy to configure the ophthalmic apparatus so that the difference between the resolution of the ophthalmic apparatus when ωin is small and the resolution of the ophthalmic apparatus when ωin is maximum is within an allowable range. Note that it is preferable for the configuration of an ophthalmic apparatus for UWF to simultaneously satisfy conditional expressions (8) and (9).

[0059] It is also preferable that the following conditional expressions (10) and (11) be satisfied. 1 <Mpar (10) 1 <Mmax (11) By satisfying conditional expressions (10) and (11), it becomes easy to obtain a large external illumination angle. Furthermore, it is more preferable that Mmax satisfies the following conditional expression (11A). It is even more preferable that the lower limit of conditional expression (11A) be 2.5 and the upper limit be 3. 2 <Mmax<5 (11A)

[0060] Furthermore, when considering the above conditional expression (7) from the perspective of the area of ​​the subject's eye 12 to be scanned, if M at the center of the subject's eye 12 including the intersection with the optical axis AX is Mc and M at the peripheral part of the subject's eye 12 is Mp, it is preferable to satisfy the following conditional expression (7A): Mc <Mp (7A) Mpar and Mc are approximate values. Furthermore, when the light ray at the maximum angle of view reaches the peripheral portion of the subject's eye 12, Mmax and Mp are the same value. By satisfying conditional expression (7A), it is possible to obtain the same effect as when conditional expression (7) is satisfied.

[0061] FIG. 8 illustrates the relationship between ωin and ωout in an objective lens system according to an example of this embodiment, using a solid line. The horizontal axis of the graph in FIG. 8 represents ωin, and the vertical axis represents ωout. A galvanometer mirror or polygon mirror is used as the scanner, but to prevent the device from becoming large and expensive, it is desirable to maximize ωout while keeping ωin as small as possible. Therefore, in this example, M, the ratio of ωin to ωout, is not constant. For comparison, FIG. 8 also illustrates the relationship between ωin and ωout for a comparative example in which M is constant over the entire field angle, using a dashed line. While the value of M in the comparative example is linear, in this example of this embodiment, the exit angle ωout increases rapidly as the incident angle ωin increases.

[0062] Further, the graph of FIG. 9 illustrates the relationship between ωout and M of the objective lens system according to an example of the present embodiment. The horizontal axis of FIG. 9 is ωout, and the vertical axis is M. The examples shown in FIGS. 8 and 9 satisfy the above conditional expressions (7) to (11). Also, this example has a range where M increases as ωin increases between Mpar and Mmax. Note that it is more preferable to adopt a configuration in which M increases as ωin increases in the entire range from Mpar to Mmax.

[0063] The angular distribution of the angular magnification as described above is not limited to the objective lens system illustrated in FIG. 7, and is a preferable configuration in an objective lens system that maintains an external irradiation angle of about 100 degrees or more. As described above in relation to the conditions represented by conditional expressions (2) and (3), as an objective lens for UWF, it is preferable that the paraxial angular magnification is greater than 1.5, and more preferably, it satisfies the conditional expression 1.5 < Mpar < 5.0 regarding the paraxial angular magnification Mpar. Practically, it is advantageous that the lower limit value of the paraxial angular magnification is greater than 1.8. Also, it is advantageous that the upper limit value is less than 4.0 in order not to make the scanning angle of the scanning means as UWF too large.

[0064] Next, the light beam diameter of the light irradiated onto the pupil plane of the eye to be examined 12 by the wide-angle optical system 30 will be considered. In an ophthalmic apparatus, it is preferable that the light beam diameter is below a desired value on the pupil plane of the eye to be examined 12 even when the scanning angle ωin changes. If the light beam diameter exceeds the desired value, there will be a problem that the light will not enter the pupil of the eye to be examined 12. Also, peripheral light beams, that is, light beams with a large ωin, pass through the peripheral part of the lens of the objective lens system 300, so the influence of the aberration of the objective lens system 300 appears greatly and is likely to fluctuate in the meridional direction on the pupil of the eye to be examined 12, causing wobbling.

[0065] Therefore, in this embodiment, when the maximum value of the angle between the emitted light beam emitted from the objective lens system 300 to the test eye 12 and the optical axis AX of the objective lens system 300 is ωmax, the meridional beam diameter of the emitted light beam at the position of the pupil plane Pp of the test eye 12 when the angle between the emitted light beam and the optical axis AX is ωmax is Pmax, and the meridional beam diameter of the emitted light beam at the position of the pupil plane Pp of the test eye 12 when the angle between the emitted light beam and the optical axis AX is minimum is Pmin, the following conditional expression (12) is satisfied. Pmax <Pmin×0.7 / (cos(ωmax)) (12) By satisfying conditional expression (12), the diameter of the light beam in the meridional direction on the pupil of the eye 12 to be examined can be made small, and a configuration can be achieved in which the light beam can easily enter the pupil of the eye 12 to be examined.

[0066] FIG. 10 is a conceptual diagram of a light beam emerging from the scanner's reflecting surface 22A, passing through the objective lens system 300, and entering the pupil plane Pp. FIG. 10 illustrates a YZ plane, with the direction of the optical axis AX defined as the Z direction and the scanning direction of the scanner's reflecting surface 22A defined as the Y direction. That is, in the configuration illustrated in FIG. 10, the meridional direction is the Y direction. Also, in FIG. 10, the dashed line indicates the light beam when the angle between the emerging light beam and the optical axis AX is the maximum angle ωmax, and the two-dot chain line indicates the light beam when the angle between the emerging light beam and the optical axis AX is the minimum. As explained above with reference to FIG. 7, the objective lens system 300 is configured to optically conjugate the scanning center position Ps of the scanner and the position of the pupil plane Pp in the paraxial region. In FIG. 7, the pupil position is shown as a plane perpendicular to the optical axis AX, i.e., the position of the pupil plane Pp. Therefore, the scanning light beam reflected by the reflecting surface 22A arranged on the optical axis AX passes through the objective lens system 300 and intersects with the pupil plane Pp. In the configuration of Fig. 10, the cross-sectional diameter in the meridional direction on the pupil plane Pp of the light beam approximately parallel to the optical axis, indicated by the two-dot chain line, is Pmin. Furthermore, the cross-sectional diameter in the meridional direction on the pupil plane Pp of the light beam at the maximum angle ωmax from the objective lens system 300, indicated by the dashed line, is Pmax.

[0067] FIG. 11 schematically shows the shapes of the two light beams, indicated by the dashed line and the two-dot chain line in FIG. 10, on the pupil plane of the subject's eye 12. FIG. 11 illustrates the XY plane, with the Y direction being the vertical direction of the page. In FIG. 11, the shape of the pupil 12B of the subject's eye 12 is shown by a solid line, the shape of the light beam when the angle between the exiting light beam and the optical axis AX is the maximum angle ωmax is shown by a dashed line, and the shape of the light beam when the angle between the exiting light beam and the optical axis AX is the minimum is shown by a dashed line. The shape of the light beam indicated by the two-dot chain line is approximately circular, while the shape of the light beam indicated by the dashed line is reduced in the Y direction, i.e., the meridional direction. This shape makes it easy for the exiting light beam from the objective lens system 300 to enter the pupil 12B of the subject's eye 12 even when wobbling occurs. 11, for the sake of explanation, the light beam is assumed to be angularly scanned in the Y direction, but in reality, the light beam is angularly scanned in two dimensions of X and Y with the axial position of the pupil plane Pp as the center. For this reason, the Y direction shown in FIG. 11 does not necessarily coincide with the scanning direction of the scanner, and the diameter of the light beam is the diameter in the meridional direction.

[0068] In order for the light beam to be efficiently incident on the pupil 12B of the eye 12 to be examined, it is preferable to further satisfy the following conditional expression (13). Pmax <Pmin (13) If conditional expression (13) is not satisfied, it is necessary to manage the position of the light beam on the pupil when the angle between the exit light beam and the optical axis AX is ωmax in design and manufacturing, which increases the difficulty of manufacturing.

[0069] It is also preferable to satisfy the following conditional expression (14): 0.2×Pmin <Pmax (14) If conditional expression (14) is not satisfied, the change in the diameter of the light beam on the retina becomes too significant. It is preferable that the ophthalmic apparatus be configured so that conditional expressions (13) and (14) are satisfied simultaneously.

[0070] Figure 12 illustrates the relationship between ωout and Pmax / Pmin for an objective lens system according to one example of this embodiment, using a solid line. The horizontal axis of Figure 12 represents the angle ωout between the optical axis AX and the light beam that passes through this objective lens system and enters the pupil plane Pp, and the vertical axis represents Pmax / Pmin. Unlike this embodiment, in a system in which the light beam diameter is not taken into consideration, the light beam diameter in the meridional direction on the pupil 12B of the subject's eye 12 should have a relationship of 1 / cos(ωout). In Figure 12, the characteristics of such a system in which the light beam diameter is not taken into consideration are shown by a dashed line as a comparative example.

[0071] 12, when the maximum angle of ωout is 72 degrees, the comparative example shown by the dashed line is 320%. In contrast, in this embodiment shown by the solid line, the objective lens system is suitably designed so that Pmax / Pmin is 1 or less, resulting in approximately 64%.

[0072] Next, the configuration of the objective lens system according to this embodiment will be described with reference to Fig. 13. In the description of the configuration of the lens system in this specification, "consists of" is used in the sense of considering only lenses as components, and does not take into consideration anything other than lenses (for example, optical elements without refractive power such as filters and prisms, apertures, etc.). In other words, in this specification, "the objective lens system consists of a front group and a rear group" means that the lens groups that make up the objective lens system are only the front group and the rear group, but the objective lens system may also be configured to include other elements other than lenses.

[0073] FIG. 13 shows the configuration of an objective lens system according to this embodiment and also shows the configuration of Example 1-1, which will be described later. Note that the overall configuration and group configuration will be mainly described here, and the detailed configuration of each lens will be described in the Examples section, which will be described later. The objective lens system 311 shown in FIG. 13 includes, in order from the scanner side, a first lens group G1 and a third lens group G3. The first lens group G1 and the third lens group G3 are separated by the largest air gap within the objective lens system 311. The third lens group G3 is an example of a common lens group 28. This largest air gap is advantageous for providing a combining unit 26, such as a dichroic mirror, that has light combining and light separating functions, making it possible to configure a hybrid objective lens system for SLO and OCT.

[0074] By dividing the objective lens system 311 into groups based on the maximum air gap, the objective lens system 311 can be considered to be composed of a front lens group GF having positive refractive power and a rear lens group GR having positive refractive power and disposed on the test-eye side of the front lens group GF, with the front lens group GF and the rear lens group GR being separated by the maximum air gap on the optical axis between the lens surfaces in the objective lens system 311. In the example of FIG. 13 , the first lens group G1 corresponds to the front lens group GF, and the third lens group G3 corresponds to the rear lens group GR. In the example of the OCT objective lens system 32 composed of the second lens group G2 and the third lens group G3 in FIG. 3 , the second lens group G2 corresponds to the front lens group GF, and the third lens group G3 corresponds to the rear lens group GR. Note that if there are two or more maximum air gaps on the optical axis between lens surfaces in the objective lens system 311, the front lens group GF and the rear lens group GR are divided by the maximum air gap closest to the test-eye side.

[0075] The front group GF has the function of converting the inclination angle of a light ray incident from the light source side to a smaller angle and transmitting it to the rear group GR. As shown in Figure 13, the angle of light ray 45 at the maximum angle of view relative to the optical axis AX when it emerges from the front group GF is smaller than the angle at which it enters the front group GF. On the other hand, the angle of light ray emerging from the rear group GR toward the subject's eye relative to the optical axis AX is very large, making this lens suitable for use as a UWF objective lens.

[0076] As described above, the objective lens system according to this embodiment, which is suitable as an optical system for guiding light from a light source to an eye to be examined, is configured to satisfy the following conditional expression (15), where TL is the geometric distance on the optical axis from the lens surface of the objective lens system closest to the light source to the lens surface of the objective lens system closest to the eye to be examined, and f is the focal length of the objective lens system. TL corresponds to the so-called total lens length. Conditional expression (15) is one condition that must be satisfied by an objective lens system that is an afocal optical system. By satisfying the conditions of an afocal optical system, a substantially parallel light beam can be incident on the eye to be examined. This makes it possible to observe the eye to be examined well while suppressing the effects of individual differences in the shape, size, etc. of the eye to be examined. -1 <TL / f<1 (15)

[0077] Furthermore, when the focal length of the front group GF is fF and the focal length of the rear group GR is fR, the objective lens system according to this embodiment preferably satisfies the following conditional expression (16) as a UWF objective lens: 1 <fF / fR<4 (16) When the light rays between the front group GF and the rear group GR are nearly parallel to the optical axis AX, fF / fR is nearly synonymous with the paraxial angular magnification Mpar. By satisfying the conditional expression related to Mmax mentioned above in addition to conditional expression (16), a large external illumination angle can be obtained. For UWF objective lenses, it is more preferable that fF / fR be greater than 1.5.

[0078] Furthermore, it is preferable that the objective lens system according to this embodiment satisfies the following conditional expression (17), where D is the maximum air gap on the optical axis separating the front group GF and the rear group GR, and TL is the geometric distance on the optical axis from the lens surface of the objective lens system closest to the light source to the lens surface of the objective lens system closest to the eye to be examined. 0.1 <D / TL<0.5 (17) If the lower limit of condition (17) is not satisfied, the lens density within a given overall lens length becomes high, resulting in an increase in weight, whereas if the upper limit of condition (17) is not satisfied, it becomes impossible to fit the lens components necessary for aberration correction within a given overall lens length.

[0079] More specifically, the rear group GR is composed of the group A GRA, which has positive refractive power, and the group B GRB, which is positioned on the examinee's eye side of the group A GRA and also has positive refractive power. The group A GRA includes at least one cemented lens with positive refractive power as a whole, and the lens surface of the group A GRA closest to the examinee's eye is convex or flat. The group B GRB is composed of one or more positive meniscus lens components with their concave surface facing the examinee's eye. This configuration of the group B GRB enables excellent correction of ray aberrations.

[0080] If the focal length of the B group GRB is fB and the focal length of the rear group GR is fR, it is preferable that the following conditional expression (18) be satisfied. 0.4 <fB / fR<2.5 (18) If the lower limit of conditional expression (18) is not satisfied, it becomes difficult to correct chromatic aberrations and higher-order aberrations. If the upper limit of conditional expression (18) is not satisfied, the entire lens system becomes large and heavy. It is more preferable that the lower limit of conditional expression (18) be 0.5 and the upper limit be 1.75, and it is even more preferable that the lower limit be 0.8 and the upper limit be 1.1.

[0081] Furthermore, if the focal length of the positive lens constituting the cemented lens included in the A group GRA is denoted by fAp and the focal length of the rear group GR is denoted by fR, it is preferable that all of the positive lenses in all of the cemented lenses included in the A group GRA satisfy the following conditional expression (19): 0.9 <fAp / fR<3.7 (19) If the lower limit of conditional expression (19) is not satisfied, the volume of the glass material increases, resulting in higher costs and weight. If the upper limit of conditional expression (19) is not satisfied, correction of chromatic aberration becomes insufficient. It is more preferable that the lower limit of conditional expression (19) be 1.7 and the upper limit be 3.

[0082] The front group GF preferably has a lens surface with negative refractive power and a lens surface with positive refractive power located on the eye-to-be-examined side of the lens surface. This configuration enables better correction of high-order ray aberrations on the wide-angle side, particularly field curvature and coma.

[0083] As an example, if the front group GF has a positive meniscus lens with a convex surface facing the eye to be examined, the concave surface of this positive meniscus lens facing the scanner becomes the lens surface with the negative refractive power described above, and the convex surface of this positive meniscus lens facing the eye to be examined becomes the lens surface with positive refractive power, making it possible to correct high-order ray aberrations on the wide-angle side.

[0084] Furthermore, if the front group GF has a meniscus lens with its convex surface facing the scanner, it is preferable to further have a negative lens and a positive lens on the test-eye side of this meniscus lens. This configuration not only has the effect of correcting high-order ray aberrations on the wide-angle side, but also makes it possible to correct lateral chromatic aberration depending on the glass material selected. If correction of lateral chromatic aberration is not necessary, it is also possible to more accurately correct high-order ray aberrations on the wide-angle side.

[0085] Furthermore, it is preferable that the front group GF has a negative lens and a positive lens arranged on the test-eye side of the negative lens, and that an air lens with negative refractive power is formed between the negative lens and the positive lens. This configuration makes it possible to correct high-order ray aberrations, particularly field curvature and coma, on the wide-angle side. Furthermore, in the configuration in which the air lens is formed, it is preferable that the negative lens and the positive lens are arranged with their concave surfaces facing each other. This configuration makes it possible to correct high-order ray aberrations, particularly field curvature and coma, on the wide-angle side. Furthermore, in the configuration in which the air lens is formed, it is preferable that the negative lens constituting the air lens further has a meniscus lens with its concave surface facing the test-eye side on the scanner side, and that the positive lens constituting the air lens further has a positive lens on the test-eye side. This configuration not only corrects high-order ray aberrations on the wide-angle side, but also makes it possible to correct chromatic aberration of magnification depending on the glass material selected. If there is no need to correct lateral chromatic aberration, it is also possible to correct high-order ray aberrations at wide angles of view with higher accuracy.

[0086] It is preferable that the A group GRA of the rear group GR has one or more cemented lenses. This configuration makes it possible to correct axial chromatic aberration and pupil chromatic aberration. It is preferable that the A group GRA has two or more cemented lenses. This configuration makes it possible to correct axial chromatic aberration and pupil chromatic aberration with greater precision.

[0087] The rear group GR, B group GRB, preferably includes one or more positive meniscus single lenses. This lens can receive wide-angle light rays closest to the subject's eye aplanatically and bend them without causing higher-order ray aberrations, particularly field curvature and coma. By using a single lens, unnecessary ray aberrations caused by cemented surfaces are prevented. To enhance this effect, it is preferable that the rear group GRRB be composed of only one or more positive meniscus single lenses.

[0088] 13 has a plurality of the above-described preferable configurations, and the angle formed by the light ray 45 with the maximum angle of view and the optical axis AX of the objective lens system when the light ray 45 is emitted from the objective lens system 311 toward the eye to be examined is 50 degrees or more. This means that the objective lens system 311 is a wide-angle optical system for fundus imaging.

[0089] DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, numerical examples of the objective lens system of the technology of the present disclosure will be described. Among the examples described below, Example 1-1, Example 2-1, Example 3-1, Example 4-1, Example 5-1, Example 6-1, Example 7-1, Example 8-1, Example 9-1, Example 10-1, and Example 11-1 are examples of objective lens systems for SLO, and Example 1-2, Example 2-2, and Example 3-2 are examples of objective lens systems for OCT. Furthermore, Example 1-1 and Example 1-2 share a common lens group, and Example 1-1 and Example 1-2 can be used to form Example 1 of a compound objective lens system. Similarly, Example 2-1 and Example 2-2 share a common lens group, and Example 2-1 and Example 2-2 can be used to form Example 2 of a compound objective lens system. Similarly, Example 3-1 and Example 3-2 share a common lens group, and Example 3-1 and Example 3-2 can be used to form Example 3 of a compound objective lens system.

[0090] Each embodiment is an ultra-wide-angle objective lens system in which the above-mentioned ωmax easily exceeds 60 degrees and reaches 72 degrees. Since the external illumination angle can be set to twice the ωmax, the following embodiments make it possible to realize an ultra-wide-angle ophthalmic apparatus that has an external illumination angle of 120 degrees to 144 degrees and enables fundus photography with an internal illumination angle of more than 200 degrees.

[0091] Example 1-1 Example 1-1 is an objective lens system 311 designed for use with an SLO objective lens system having a wavelength range of 450 nm to 650 nm and a reference wavelength of 520 nm. FIG. 13 shows the lens configuration of the objective lens system 311 of Example 1-1, along with the scanner scanning center position Ps and the pupil plane Pp of the subject's eye 12. Note that Ps and Pp in the figure are shown to indicate positions in the optical axis direction, and do not represent shapes or sizes. The objective lens system 311 includes, in order from the scanner side, a first lens group G1 and a third lens group G3. The first lens group G1 and the third lens group G3 are separated by the largest air gap within the objective lens system 311.

[0092] The first lens group G1 includes a meniscus lens L11 with a convex surface facing the scanner side, a meniscus lens L12 with a convex surface facing the scanner side, a negative lens L13 with a concave surface facing the scanner side, a positive meniscus lens L14 with a convex surface facing the test eye side, and a positive lens L15. Lenses L11 and L12 are cemented together to form a meniscus-shaped lens component with a convex surface facing the scanner side, and the lens surface closest to the scanner is aspheric. The third lens group G3 includes a positive lens L31, a positive lens L32, a negative lens L33, a positive lens L34, a biconcave negative lens L35, and a positive meniscus lens L36 with a concave surface facing the test eye side. More specifically, the absolute value of the radius of curvature of the positive lens L34's surface facing the scanner side is smaller than the absolute value of the radius of curvature of the surface facing the test eye side. Lenses L32 and L33, and lenses L34 and L35, are cemented together. More specifically, the lenses L32 and L33 are cemented together to form a biconvex lens component, and the lenses L34 and L35 form a positive lens component with the convex surface facing the scanner side.

[0093] The objective lens system 311 can be considered to be composed of the front group GF and rear group GR described above. The front group GF corresponds to the first lens group G1, and the rear group GR corresponds to the third lens group G3. The A group GRA consists of lenses L31, L32, and L33. The B group GRB consists of lenses L34, L35, and L36.

[0094] Table 1 shows the lens data for Example 1-1. The lens data shows, from the left column to the right, the surface number, radius of curvature, surface spacing on the optical axis, refractive index based on the d-line (wavelength 587.56 nm), and Abbe number based on the d-line. The first surface in the lens data is the scanning center position Ps of the scanner, and the value in the last row of the thickness column shows the distance on the optical axis from the lens surface closest to the subject's eye in the table to the pupil plane Pp. [Table 1]

[0095] In Table 1, aspheric surfaces are indicated by (ASP) in the surface number column. An aspheric surface is expressed by the equation below, where h is the height in the direction perpendicular to the optical axis, zs is the distance along the optical axis from the tangent plane at the vertex of the aspheric surface to the position on the aspheric surface at height h, c is the reciprocal of the paraxial radius of curvature, k is the conic coefficient, A is the fourth-order aspheric coefficient, B is the sixth-order aspheric coefficient, C is the eighth-order aspheric coefficient, D is the tenth-order aspheric coefficient, and E is the twelfth-order aspheric coefficient. zs=(c·h 2 ) / 〔1+{1-(1+k)·h 2 ·c 2} 1 / 2 〕 +A·h 4 +B·h 6 +C·h 8 +D·h 10 +E·h 12

[0096] Table 2 shows the aspherical coefficients of the aspherical surface of Example 1-1. In Table 2, "En" (n is an integer) means "×10 -n " means. [Table 2] The above-mentioned methods of describing the lens data and aspherical coefficients and the methods of illustrating the configuration diagrams are basically the same for the following examples.

[0097] Fig. 14 shows the relationship between ωout and M in Example 1-1. In Fig. 15, the relationship between ωout and Pmax / Pmin in Example 1-1 is shown by a solid line, and the curve for 1 / cos(ωout) is shown by a dashed line. This Example 1-1 is an SLO objective lens system with an external illumination angle of 132 degrees, and as shown in Figs. 14 and 15, it is clear that it has excellent performance as a UWF objective lens.

[0098] Example 1-2 Example 1-2 is an objective lens system 321 designed for use with an OCT objective lens system having a wavelength range of 900 nm to 1050 nm and a reference wavelength of 1000 nm. FIG. 16 shows the lens configuration of the objective lens system 321 of Example 1-2. The objective lens system 321 includes, in order from the scanner side, a second lens group G2 and a third lens group G3. The second lens group G2 and the third lens group G3 are separated by the longest air gap within the objective lens system 321. This longest air gap is ideal for providing a combining unit 26, such as a dichroic mirror, that has light combining and light separating functions, making it possible to configure a hybrid objective lens system for SLO and OCT.

[0099] The second lens group G2 has a configuration similar to that of the first lens group G1 in Example 1-1, but the meniscus lens component with its convex surface facing the scanner side is formed by a cemented lens of a biconvex positive lens L21 and a biconcave negative lens L22. The third lens group G3 in Example 1-2 is common to the third lens group G3 in Example 1-1.

[0100] The objective lens system 321 can be considered to be composed of the front group GF and rear group GR described above. The front group GF corresponds to the second lens group G2, and the rear group GR corresponds to the third lens group G3. The lenses that make up the A group GRA and the B group GRB are the same as those in Example 1-1.

[0101] Table 3 shows the lens data of Example 1-2. [Table 3]

[0102] Table 4 shows the aspherical coefficients of the aspherical surface of Example 1-2. [Table 4]

[0103] Fig. 17 shows the relationship between ωout and M in Example 1-2. Fig. 18 shows the relationship between ωout and Pmax / Pmin in Example 1-2 with a solid line, and the curve for 1 / cos(ωout) with a dashed line. This Example 1-2 is an OCT objective lens system with an external illumination angle of 128 degrees, and as shown in Figs. 17 and 18, it is clear that it has excellent performance as a UWF objective lens.

[0104] Example 2-1 Example 2-1 is an objective lens system 312 designed for use with an SLO. Fig. 19 shows the lens configuration of the objective lens system 312 of Example 2-1. The objective lens system 312 includes, in order from the scanner side, a first lens group G1 and a third lens group G3. The first lens group G1 and the third lens group G3 are separated by the largest air gap within the objective lens system 312.

[0105] The first lens group G1 includes a biconvex positive lens L11, a biconcave negative lens L12, a biconcave negative lens L13, a positive lens L14 with a convex surface facing the test eye, and a positive lens L15. Lenses L11 and L12 are cemented together to form a meniscus lens component with a convex surface facing the scanner, and the lens surface closest to the scanner is aspheric. The third lens group G3 includes a positive lens L31, a biconvex positive lens L32, a biconcave negative lens L33, a positive lens L34 with a convex surface facing the scanner, and a positive meniscus lens L35 with a concave surface facing the test eye. Lenses L32 and L33 are cemented together to form a meniscus lens component with a convex surface facing the scanner.

[0106] The objective lens system 312 can be considered to be composed of the front group GF and rear group GR described above. The front group GF corresponds to the first lens group G1, and the rear group GR corresponds to the third lens group G3. The A group GRA consists of lenses L31, L32, L33, and L34. The B group GRB consists of lens L35.

[0107] Table 5 shows the lens data of Example 2-1. [Table 5]

[0108] Table 6 shows the aspherical coefficients of the aspherical surface of Example 2-1. [Table 6]

[0109] Fig. 20 shows the relationship between ωout and M in Example 2-1. In Fig. 21, the relationship between ωout and Pmax / Pmin in Example 2-1 is shown by a solid line, and the curve for 1 / cos(ωout) is shown by a dashed line. This Example 2-1 is an SLO objective lens system with an external illumination angle of 144 degrees, and as shown in Figs. 20 and 21, it is clear that it has excellent performance as a UWF objective lens.

[0110] Example 2-2 Example 2-2 is an objective lens system 322 intended for use in OCT. FIG. 22 shows the lens configuration of the objective lens system 322 of Example 2-2. The objective lens system 322 includes, in order from the scanner side, a second lens group G2 and a third lens group G3. The second lens group G2 and the third lens group G3 are separated by the largest air gap within the objective lens system 322. The second lens group G2 has a configuration similar to the first lens group G1 of Example 2-1 shown in FIG. 19. The third lens group G3 of Example 2-2 is the same as the third lens group G3 of Example 2-1.

[0111] The objective lens system 322 can be considered to be composed of the front group GF and rear group GR described above. The front group GF corresponds to the second lens group G2, and the rear group GR corresponds to the third lens group G3. The lenses that make up the A group GRA and the B group GRB are the same as those in Example 2-1.

[0112] Table 7 shows the lens data for Example 2-2. [Table 7]

[0113] Table 8 shows the aspherical coefficients of the aspherical surface of Example 2-2. [Table 8]

[0114] Fig. 23 shows the relationship between ωout and M in Example 2-2. In Fig. 24, the relationship between ωout and Pmax / Pmin in Example 2-2 is shown by a solid line, and the curve for 1 / cos(ωout) is shown by a dashed line. This Example 2-2 is an OCT objective lens system with an external illumination angle of 144 degrees, and as shown in Figs. 23 and 24, it is clear that it has excellent performance as a UWF objective lens.

[0115] Example 3-1 Example 3-1 is an objective lens system 313 designed for use with an SLO. Fig. 25 shows the lens configuration of the objective lens system 313 of Example 3-1. The objective lens system 313 includes, in order from the scanner side, a first lens group G1 and a third lens group G3. The first lens group G1 and the third lens group G3 are separated by the largest air gap within the objective lens system 313.

[0116] The first lens group G1 includes a negative meniscus lens L11 with a convex surface facing the scanner side, a positive meniscus lens L12 with a convex surface facing the scanner side, a biconcave negative lens L13, a positive lens L14 with a convex surface facing the test eye side, and a positive lens L15. Lenses L11 and L12 are cemented together to form a meniscus lens component with a convex surface facing the scanner side. The third lens group G3 includes a negative meniscus lens L31 with a convex surface facing the scanner side, a biconvex positive lens L32, a biconvex positive lens L33, a negative meniscus lens L34 with a convex surface facing the test eye side, a positive lens L35 with a convex surface facing the scanner side, and a positive meniscus lens L36 with a concave surface facing the test eye side. Lenses L31 and L32 are cemented together to form a biconvex positive lens component, and lenses L33 and L34 are also cemented together to form a biconvex positive lens component. The third lens group G3 of Example 3-1 also has two cemented lenses, as in Example 1-1 (FIG. 13), but while the two cemented surfaces of the third lens group G3 in Example 1-1 both have convex surfaces facing the eye to be examined, in Example 3-1, the cemented surfaces are formed with concave surfaces facing each other, and the lens surface closest to the eye to be examined is aspherical.

[0117] The objective lens system 313 can be considered to be composed of the front group GF and rear group GR described above. The front group GF corresponds to the first lens group G1, and the rear group GR corresponds to the third lens group G3. The A group GRA consists of lenses L31, L32, L33, L34, and L35. The B group GRB consists of lens L36.

[0118] Table 9 shows the lens data for Example 3-1. [Table 9]

[0119] Table 10 shows the aspherical coefficients of the aspherical surface of Example 3-1. [Table 10]

[0120] Fig. 26 shows the relationship between ωout and M in Example 3-1. Fig. 27 shows the relationship between ωout and Pmax / Pmin in Example 3-1 with a solid line, and the curve for 1 / cos(ωout) with a dashed line. This Example 3-1 is also an SLO objective lens system with an external illumination angle of 144 degrees, and as shown in Figs. 26 and 27, it is clear that it has excellent performance as a UWF objective lens.

[0121] Example 3-2 Example 3-2 is an objective lens system 323 intended for use in OCT. Fig. 28 shows the lens configuration of the objective lens system 323 of Example 3-2. The objective lens system 323 includes, in order from the scanner side, a second lens group G2 and a third lens group G3. Second lens group G2 and the third lens group G3 are separated by the largest air gap within the objective lens system 323. The second lens group G2 has a configuration similar to that of the first lens group G1 shown in FIG. 25. However, while the meniscus lens component with its convex surface facing the scanner side of the first lens group G1 in Example 3-1 has the smallest center thickness of all the components in the first lens group G1, the first lens group G1 in Example 3-2 has the largest center thickness of all the components in the first lens group G1. The third lens group G3 in Example 3-2 is common to the third lens group G3 in Example 3-1.

[0122] The objective lens system 323 can be considered to be composed of the front group GF and rear group GR described above. The front group GF corresponds to the second lens group G2, and the rear group GR corresponds to the third lens group G3. The lenses that make up the A group GRA and the B group GRB are the same as those in Example 3-1.

[0123] Table 11 shows the lens data for Example 3-2. [Table 11]

[0124] Table 12 shows the aspherical coefficients of the aspherical surface of Example 3-2. [Table 12]

[0125] Fig. 29 shows the relationship between ωout and M in Example 3-2. Fig. 30 shows the relationship between ωout and Pmax / Pmin in Example 3-2 with a solid line, and the curve for 1 / cos(ωout) with a dashed line. This Example 3-2 is also an OCT objective lens system with an external illumination angle of 144 degrees, and as shown in Figs. 29 and 30, it is clear that it has excellent performance as a UWF objective lens.

[0126] Example 4-1 Example 4-1 is an objective lens system 314 designed for use with an SLO. Fig. 31 shows the lens configuration of the objective lens system 314 of Example 4-1. The objective lens system 314 includes, in order from the scanner side, a first lens group G1 and a third lens group G3. The first lens group G1 and the third lens group G3 are separated by the largest air gap within the objective lens system 314.

[0127] The first lens group G1 includes a positive meniscus lens L11 with a concave surface facing the scanner side, a negative meniscus lens L12 with a concave surface facing the scanner side, a negative meniscus lens L13 with a convex surface facing the scanner side, and a positive lens L14. Lenses L11 and L12 are cemented together to form a meniscus lens component with a concave surface facing the scanner side. The third lens group G3 includes a positive lens L31, a biconvex positive lens L32, a negative lens L33 with a concave surface facing the scanner side, a positive meniscus lens L34 with a concave surface facing the test eye side, and a positive meniscus lens L35 with a concave surface facing the test eye side. Lenses L32 and L33 are cemented together to form a positive lens component. The positive meniscus lens L34 of Example 4-1 has a diffractive optical element (abbreviated as DOE) on its convex surface facing the scanner side. By providing a diffractive optical element on a lens surface, not only does it become easier to correct chromatic aberration, but it is also possible to reduce the effective diameter of the lens by utilizing refraction by the lens surface and diffraction by the diffractive optical element. Diffractive optical elements can also be provided on other lens surfaces, and it is effective to provide them on, for example, lenses with large effective diameters such as lens L31, or on lenses L11 and L12, which constitute the lens component closest to the scanner.

[0128] The objective lens system 314 can be considered to be composed of the front group GF and rear group GR described above. The front group GF corresponds to the first lens group G1, and the rear group GR corresponds to the third lens group G3. The A group GRA consists of lens L31. The B group GRB consists of lens L32, lens L33, lens L34, and lens L35.

[0129] Table 13 shows the lens data for Example 4-1. [Table 13]

[0130] In Table 13, surfaces on which diffractive optical elements are provided are marked with (DOE) in the surface number column. The phase shape ψ of the diffractive surface is expressed by the following equation, where h is the height in the direction perpendicular to the optical axis, m is the diffraction order of the diffracted light, λ0 is the design wavelength, C2 is the second-order phase coefficient, C4 is the fourth-order phase coefficient, and C6 is the sixth-order phase coefficient. ψ(h,m)=[2π / (m×λ0)]×(C2·h 2 +C4·h 4 +C6·h 6 )

[0131] Table 14 shows the phase coefficients of the diffractive surface of Example 4-1. In Table 20, "En" (n is an integer) means "×10 -n " means. [Table 14]

[0132] Fig. 32 shows the relationship between ωout and M in Example 4-1. In Fig. 33, the relationship between ωout and Pmax / Pmin in Example 4-1 is shown by a solid line, and the curve for 1 / cos(ωout) is shown by a dashed line. This Example 4-1 is an SLO objective lens system with an external illumination angle of 130 degrees, and as shown in Figs. 32 and 33, it is clear that it has excellent performance as a UWF objective lens.

[0133] Example 5-1 Example 5-1 is an objective lens system 315 that is intended for an SLO objective lens system. Figure 34 shows the lens configuration of the objective lens system 315 of Example 5-1. The objective lens system 315 is The objective lens system 315 includes, in order from the scanner side, a first lens group G1 and a third lens group G3. The first lens group G1 and the third lens group G3 are separated by the largest air gap in the objective lens system 315.

[0134] The first lens group G1 includes a negative meniscus lens L11 with a convex surface facing the scanner side and a positive meniscus lens L12 with a convex surface facing the test eye side. The third lens group G3 includes a negative meniscus lens L31 with a convex surface facing the scanner side, a biconvex positive lens L32, a biconvex positive lens L33, a negative meniscus lens L34 with a convex surface facing the test eye side, a biconvex positive lens L35, a negative meniscus lens L36 with a convex surface facing the test eye side, a positive lens L37 with a convex surface facing the scanner side, a positive meniscus lens L38 with a concave surface facing the test eye side, and a positive meniscus lens L39 with a concave surface facing the test eye side. The lenses L31 and L32 are cemented together to form a biconvex positive lens component. The lenses L33 and L34 are cemented together to form a biconvex positive lens component. The lens L35 and the lens L36 are cemented together to form a biconvex positive lens component.

[0135] The objective lens system 315 can be considered to be composed of the front group GF and rear group GR described above. The front group GF corresponds to the first lens group G1, and the rear group GR corresponds to the third lens group G3. The A group GRA consists of lenses L31, L32, L33, L34, L35, L36, and L37. The B group GRB consists of lenses L38 and L39.

[0136] Table 15 shows the lens data for Example 5-1. [Table 15]

[0137] The relationship between ωout and M in Example 5-1 has a qualitatively similar tendency to Examples 1-1 to 4-1. The relationship between ωout and Pmax / Pmin in Example 5-1 has a qualitatively similar tendency to Example 3-1, but in Example 5-1, Pmax / Pmin takes a value of 140% or less when ωout is 70 degrees.

[0138] Example 6-1 Example 6-1 is an objective lens system 316 designed for use with an SLO. Fig. 35 shows the lens configuration of the objective lens system 316 of Example 6-1. The objective lens system 316 includes, in order from the scanner side, a first lens group G1 and a third lens group G3. The first lens group G1 and the third lens group G3 are separated by the largest air gap within the objective lens system 316.

[0139] The first lens group G1 includes a biconvex positive lens L11, a biconcave negative lens L12, and a positive meniscus lens L13 with a convex surface facing the test eye. Lenses L11 and L12 are cemented together to form a meniscus lens component with a convex surface facing the scanner. The third lens group G3 includes a negative meniscus lens L31 with a convex surface facing the scanner, a biconvex positive lens L32, a biconvex positive lens L33, a negative lens L34 with a concave surface facing the scanner, a positive meniscus lens L35 with a concave surface facing the test eye, a positive meniscus lens L36 with a concave surface facing the test eye, and a positive meniscus lens L37 with a concave surface facing the test eye. Lenses L31 and L32 are cemented together to form a biconvex positive lens component. Lenses L33 and L34 are cemented together to form a biconvex positive lens component.

[0140] The objective lens system 316 can be considered to be composed of the front group GF and rear group GR described above. The front group GF corresponds to the first lens group G1, and the rear group GR corresponds to the third lens group G3. The A group GRA consists of lenses L31, L32, L33, and L34. The B group GRB consists of lenses L35, L36, and L37.

[0141] Table 16 shows the lens data for Example 6-1. [Table 16]

[0142] The relationship between ωout and M in Example 6-1 has a qualitatively similar tendency to Examples 1-1 to 4-1. The relationship between ωout and Pmax / Pmin in Example 6-1 has a qualitatively similar tendency to Example 3-1, but in Example 6-1, Pmax / Pmin takes a value of 140% or less when ωout is 70 degrees.

[0143] Example 7-1 Example 7-1 is an objective lens system 317 designed for use with an SLO. Fig. 36 shows the lens configuration of the objective lens system 317 of Example 7-1. The objective lens system 317 includes, in order from the scanner side, a first lens group G1 and a third lens group G3. The first lens group G1 and the third lens group G3 are separated by the largest air gap within the objective lens system 317.

[0144] The first lens group G1 includes a negative meniscus lens L11 with a convex surface facing the scanner side and a positive lens L12 with a convex surface facing the test eye side. The lens surfaces of lens L12 on the scanner side and test eye side are aspheric. The third lens group G3 includes a positive meniscus lens L31 with a convex surface facing the test eye side, a biconvex positive lens L32, a negative meniscus lens L33 with a convex surface facing the test eye side, a biconvex positive lens L34, a biconcave negative lens L35, a biconvex positive lens L36, a positive meniscus lens L37 with a concave surface facing the test eye side, and a positive meniscus lens L38 with a concave surface facing the test eye side. Lenses L32 and L33 are cemented together to form a biconvex positive lens component. Lenses L34 and L35 are cemented together to form a meniscus lens component with a concave surface facing the test eye side.

[0145] The objective lens system 317 can be considered to be composed of the front group GF and rear group GR described above. The front group GF corresponds to the first lens group G1, and the rear group GR corresponds to the third lens group G3. The A group GRA consists of lenses L31, L32, L33, L34, L35, and L36. The B group GRB consists of lenses L37 and L38.

[0146] Table 17 shows the lens data for Example 7-1. [Table 17]

[0147] Table 18 shows the aspherical coefficients of the aspherical surface of Example 7-1. [Table 18]

[0148] The relationship between ωout and M in Example 7-1 has a qualitatively similar tendency to that in Examples 1-1 to 4-1. The relationship between ωout and Pmax / Pmin in Example 7-1 has a qualitatively similar tendency to that in Example 1-1.

[0149] Example 8-1 Example 8-1 is an objective lens system 318 designed for use with an SLO. Fig. 37 shows the lens configuration of the objective lens system 318 of Example 8-1. The objective lens system 318 includes, in order from the scanner side, a first lens group G1 and a third lens group G3. The first lens group G1 and the third lens group G3 are separated by the largest air gap within the objective lens system 318.

[0150] The first lens group G1 includes a positive meniscus lens L11 with a concave surface facing the scanner side. The scanner-side lens surface of lens L11 is aspheric. The third lens group G3 includes a biconvex positive lens L31, a biconcave negative lens L32, a biconvex positive lens L33, a negative meniscus lens L34 with a concave surface facing the test eye side, a positive meniscus lens L35 with a concave surface facing the test eye side, a biconvex positive lens L36, a positive meniscus lens L37 with a concave surface facing the test eye side, and a positive meniscus lens L38 with a concave surface facing the test eye side. Lenses L32 and L33 are cemented together to form a meniscus lens component with a convex surface facing the test eye side. Lenses L34 and L35 are cemented together to form a meniscus lens component with a concave surface facing the test eye side.

[0151] The objective lens system 318 can be considered to be composed of the front group GF and rear group GR described above. The front group GF corresponds to the first lens group G1, and the rear group GR corresponds to the third lens group G3. The A group GRA consists of lenses L31, L32, L33, L34, L35, and L36. The B group GRB consists of lenses L37 and L38.

[0152] Table 19 shows the lens data for Example 8-1. [Table 19]

[0153] Table 20 shows the aspherical coefficients of the aspherical surface of Example 8-1. [Table 20]

[0154] The relationship between ωout and M in Example 8-1 has a qualitatively similar tendency to that in Examples 1-1 to 4-1. The relationship between ωout and Pmax / Pmin in Example 8-1 has a qualitatively similar tendency to that in Examples 1-1 to 2-2.

[0155] Example 9-1 Example 9-1 is an objective lens system 319 designed for use with an SLO. Fig. 38 shows the lens configuration of the objective lens system 319 of Example 9-1. The objective lens system 319 includes, in order from the scanner side, a first lens group G1 and a third lens group G3. The first lens group G1 and the third lens group G3 are separated by the largest air gap within the objective lens system 319.

[0156] The first lens group G1 includes a negative meniscus lens L11 with a convex surface facing the scanner side, a biconvex positive lens L12, a biconcave negative lens L13, a biconcave negative lens L14, a biconvex positive lens L15, and a positive lens L16 with a convex surface facing the test eye side. Lenses L11 and L12 are cemented together to form a biconvex lens component. Lenses L14 and L15 are cemented together to form a meniscus lens component with a convex surface facing the test eye side. The third lens group G3 includes a biconvex positive lens L31, a negative meniscus lens L32 with a convex surface facing the test eye side, a biconvex positive lens L33, and a positive meniscus lens L34 with a concave surface facing the test eye side. Lenses L31 and L32 are cemented together to form a biconvex positive lens component.

[0157] The objective lens system 319 can be considered to be composed of the front group GF and rear group GR described above. The front group GF corresponds to the first lens group G1, and the rear group GR corresponds to the third lens group G3. The A group GRA consists of lenses L31, L32, and L33. The B group GRB consists of lens L34.

[0158] Table 21 shows the lens data for Example 9-1. [Table 21]

[0159] The relationship between ωout and M in Example 9-1 has a qualitatively similar tendency to that in Examples 1-1 to 4-1. The relationship between ωout and Pmax / Pmin in Example 9-1 has a qualitatively similar tendency to that in Example 1-1.

[0160] Example 10-1 Example 10-1 is an objective lens system 3110 intended for an SLO objective lens system. Fig. 39 shows the lens configuration of the objective lens system 3110 of Example 10-1. The objective lens system 3110 includes, in order from the scanner side, a first lens group G1 and a third lens group G3. The first lens group G1 and the third lens group G3 are separated by the largest air gap within the objective lens system 3110.

[0161] The first lens group G1 includes a biconcave negative lens L11, a positive meniscus lens L12 with its convex surface facing the test eye, a positive meniscus lens L13 with its convex surface facing the scanner, and a biconcave negative lens L14. The third lens group G3 includes a biconvex positive lens L31, a biconcave negative lens L32, a biconvex positive lens L33, a positive lens L34 with its convex surface facing the scanner, and a positive meniscus lens L35 with its concave surface facing the test eye. Lenses L31 and L32 are cemented together to form a meniscus lens component.

[0162] The objective lens system 3110 can be considered to be composed of the front group GF and rear group GR described above. The front group GF corresponds to the first lens group G1, and the rear group GR corresponds to the third lens group G3. The A group GRA consists of lenses L31, L32, L33, and L34. The B group GRB consists of lens L35.

[0163] Table 22 shows the lens data for Example 10-1. [Table 22]

[0164] The relationship between ωout and M in Example 10-1 has a qualitatively similar tendency to that in Examples 1-1 to 4-1. The relationship between ωout and Pmax / Pmin in Example 10-1 has a qualitatively similar tendency to that in Example 1-1.

[0165] Example 11-1 Example 11-1 is an objective lens system 3111 intended for an SLO objective lens system. Fig. 40 shows the lens configuration of the objective lens system 3111 of Example 11-1. The objective lens system 3111 includes, in order from the scanner side, a first lens group G1 and a third lens group G3. The first lens group G1 and the third lens group G3 are separated by the largest air gap within the objective lens system 3111.

[0166] The first lens group G1 includes a positive meniscus lens L11 with a convex surface facing the test eye, a negative meniscus lens L12 with a convex surface facing the scanner, a positive lens L13 with a convex surface facing the scanner, a biconcave negative lens L14, and a biconvex positive lens L15. Lenses L14 and L15 are cemented together to form a meniscus lens component. The third lens group G3 includes a negative meniscus lens L31 with a convex surface facing the scanner, a biconvex positive lens L32, a positive meniscus lens L33 with a concave surface facing the test eye, and a positive meniscus lens L34 with a concave surface facing the test eye. Lenses L31 and L32 are cemented together to form a biconvex positive lens component.

[0167] The objective lens system 3111 can be considered to be composed of the front group GF and rear group GR described above. The front group GF corresponds to the first lens group G1, and the rear group GR corresponds to the third lens group G3. The A group GRA consists of lenses L31 and L32. The B group GRB consists of lenses L33 and L34.

[0168] Table 23 shows the lens data for Example 11-1. [Table 23]

[0169] The relationship between ωout and M in Example 11-1 has a qualitatively similar tendency to that in Examples 1-1 to 4-1. The relationship between ωout and Pmax / Pmin in Example 11-1 has a qualitatively similar tendency to that in Example 1-1.

[0170] Tables 24 to 27 show the corresponding values ​​of each conditional expression for each example. In Table 27, the column fAp / fR(min) shows the minimum value of fAp / fR for each example, and the column fAp / fR(max) shows the maximum value of fAp / fR for each example.

[0171] [Table 24]

[0172] [Table 25]

[0173] [Table 26]

[0174] [Table 27]

[0175] Each of the above-described embodiments uses a UWF optical system with an external illumination angle exceeding 120 degrees, and the axial distance from the lens surface closest to the subject's eye to the pupil plane Pp of the subject's eye, known as a working distance, is 25 mm or more. While it is important to ensure a large working distance in the actual use of an ophthalmic apparatus incorporating a UWF optical system, the effective diameter of the objective lens increases rapidly as the working distance increases. For this reason, a practical working distance for a UWF optical system is 20 mm or more, preferably 22 mm or more. While a larger upper limit for the working distance can reduce the burden on the subject, 42 mm is considered the upper limit in terms of optical system performance, cost, and ease of manufacture.

[0176] <Another embodiment using a relay system> Next, another embodiment of the imaging optical system will be described. FIG. 41 shows a cross-sectional view of the configuration of another embodiment of the imaging optical system. Compared to the example shown in FIG. 3, the imaging optical system shown in FIG. 41 differs significantly in that it includes a relay optical system. The imaging optical system in FIG. 41 includes a first relay system 601 and an objective lens system 600 in the optical path between the first optical scanner 22 and the subject's eye 12, and a second relay system 602 and an objective lens system 600 in the optical path between the second optical scanner 24 and the subject's eye 12. The first relay system 601 includes, from the first optical scanner 22 side, a first sub-lens group RG1 and a common sub-lens group RG3. The second relay system 602 includes, from the second optical scanner 24 side, a second sub-lens group RG2 and a common sub-lens group RG3.

[0177] The imaging optical system of Figure 41 includes a combiner unit 626 that has the same function as the combiner unit 26 of Figure 3. The combiner unit 626 is arranged between the first sub-lens group RG1 and the common sub-lens group RG3, and is also arranged between the second sub-lens group RG2 and the common sub-lens group RG3. To be able to accommodate the combiner unit 626, which has incident angle dependency, the scanning light beam that passes between the first sub-lens group RG1 and the common sub-lens group RG3 is parallel light, and the scanning light beam that passes between the second sub-lens group RG2 and the common sub-lens group RG3 is also parallel light.

[0178] 41, the common lens group is composed of a common secondary lens group RG3 and an objective lens system 600. Light angularly scanned by the first optical scanner 22 passes through the first secondary lens group RG1, the combining unit 626, the common secondary lens group RG3, and the objective lens system 600 in that order before reaching the subject's eye 12. Light angularly scanned by the second optical scanner 24 passes through the second secondary lens group RG2, the combining unit 626, the common secondary lens group RG3, and the objective lens system 600 in that order before reaching the subject's eye 12.

[0179] The first relay system 601 forms a relay conjugate position Pr, which is conjugate with the first optical scanner 22, in the optical path between the combining unit 626 and the subject's eye 12. In the example shown in FIG. 41 , the first relay system 601 forms a relay conjugate position Pr in the optical path between the first relay system 601 and the objective lens system 600. The second relay system 602 forms a conjugate relationship between the second optical scanner 24 and the relay conjugate position Pr via the combining unit 626. The objective lens system 600 forms a conjugate relationship between the relay conjugate position Pr and the pupil position of the subject's eye 12. Therefore, in the configuration example shown in FIG. 41 , the first optical scanner 22 and the pupil position of the subject's eye 12 are also conjugate with each other, and the second optical scanner 24 and the pupil position of the subject's eye 12 are also conjugate with each other. By using a relay system as in the example shown in Fig. 41, even when obtaining a large external illumination angle similar to that of the example shown in Fig. 3, the diameter of the combining unit 626 in Fig. 41 can be made smaller than that of the combining unit 26 in Fig. 3, so the diameter of the combining unit can be made smaller, thereby reducing costs. In ultra-wide-angle ophthalmic optical systems, where the diameters of optical components tend to be large, significant cost reductions can be expected by using a relay system.

[0180] In this embodiment, when MR1 is the paraxial angular magnification of the first relay system 601 from the first optical scanner 22 to the relay conjugate position Pr and MR2 is the paraxial angular magnification of the second relay system 602 from the second optical scanner 24 to the relay conjugate position Pr, the following conditional expression (20) is satisfied. By satisfying conditional expression (20), the same effect as when conditional expression (1) is satisfied can be obtained. |MR1|<|MR2| (20)

[0181] Furthermore, for the purpose of miniaturization, it is preferable that MR1 satisfy the following conditional expression (21): From the conditions (20) and (21), it is preferable that MR2 satisfy the following conditional expression (22). |MR1|=1 (21) |MR2|>1 (22)

[0182] 41 includes, in order from the first optical scanner 22 side to the examined eye side, a positive meniscus lens Lr11 with its concave surface facing the first optical scanner 22 side, a biconvex positive lens Lr12, and a biconcave negative lens Lr13. The lenses Lr12 and Lr13 are cemented together to form a meniscus lens component with its convex surface facing the first optical scanner 22 side.

[0183] In the example of Figure 41, the first sub-lens group RG1 and the common sub-lens group RG3 are configured symmetrically with respect to a plane perpendicular to the optical axis. That is, the common sub-lens group RG3 includes, in order from the first optical scanner 22 side to the test eye side, a biconcave negative lens Lr31, a biconvex positive lens Lr32, and a positive meniscus lens Lr33 with its concave surface facing the test eye side. The lenses Lr31 and Lr32 are cemented together to form a meniscus-shaped lens component with its convex surface facing the test eye side. The second sub-lens group RG2 shown in Figure 41 also includes at least one positive lens and at least one negative lens, and has concave lens surfaces that face each other and are separated by an air gap.

[0184] 41, the first optical scanner 22 may be configured to scan in only one of the X and Y directions. Similarly, the second optical scanner 24 may be configured to scan in only one of the X and Y directions. In this way, when both scanners are one-dimensional scanners, by providing a one-dimensional scanner in a direction perpendicular to the one-dimensional scanning direction at the relay conjugate position Pr, which is the pupil conjugate position of the relay system, it is possible to perform two-dimensional angular scanning of the light beam on the pupil plane of the subject's eye.

[0185] The perspective view of Fig. 42 shows the configuration of yet another embodiment of an imaging optical system using the relay system described above. The configuration shown in Fig. 42 differs significantly from the configuration shown in Fig. 41 in that a third optical scanner 625 is disposed at the relay conjugate position Pr, a first optical scanner 622 is disposed instead of the first optical scanner 22 shown in Fig. 41, and a second optical scanner 624 is disposed instead of the second optical scanner 24 shown in Fig. 41. The first optical scanner 622 and the second optical scanner 624 are configured to scan in only one of the X and Y directions, and the third optical scanner 625 is configured to scan in a direction perpendicular to the scanning directions of the first optical scanner 622 and the second optical scanner 624. For example, the first optical scanner 622 may be configured to scan in the Y direction using a polygon mirror, the second optical scanner 624 may be configured to scan in the Y direction using a galvanometer mirror, and the third optical scanner 625 may be configured to scan in the X direction using a galvanometer mirror.

[0186] <Example of embodiment using relay system> For example, the objective lens system of each embodiment shown in the section <Description of Preferred Embodiments> can be used as the objective lens system 600 of the photographing optical system shown in Figures 41 and 42. As an example, Figure 41 shows an example in which the above-mentioned Example 9-1 is used as the objective lens system 600. Furthermore, the lens data and aspherical coefficients of the embodiment of the first relay system 601 shown in Figure 41 are shown in Tables 28 and 29, respectively, and the lens data and aspherical coefficients of the embodiment of the second relay system 602 are shown in Tables 30 and 31, respectively.

[0187] [Table 28]

[0188] [Table 29]

[0189] [Table 30]

[0190] [Table 31]

[0191] Table 32 shows the corresponding values ​​of the conditional expressions for the optical system that combines the relay system examples shown in Tables 28 to 31 with the objective lens system of Example 9-1. [Table 32] Here, M1 is the paraxial angular magnification of the optical system combining the first relay system 601 and the objective lens system 600, and M2 is the paraxial angular magnification of the optical system combining the second relay system 602 and the objective lens system 600. These can be considered to be the same as the paraxial angular magnifications M1 and M2 of conditional formula (1) by replacing the SLO objective lens system 31 shown in FIG. 3 with the optical system combining the first relay system 601 and the objective lens system 600 shown in FIG. 41, and by replacing the OCT objective lens system 32 shown in FIG. 3 with the optical system combining the second relay system 602 and the objective lens system 600 shown in FIG. 41. Mpar and Mmax in Table 32 can also be considered to be the same as Mpar and Mmax of conditional formula (7) by replacing the objective lens system 300 shown in FIG. 7 with the optical system combining the first relay system 601 and the objective lens system 600 shown in FIG. 41, or by replacing it with the optical system combining the second relay system 602 and the objective lens system 600 shown in FIG. 41.

[0192] Table 33 shows the corresponding values ​​of conditional expressions (20) to (22) for the examples of the relay systems shown in Tables 28 to 31. [Table 33] However, MRpar and MRmax in Table 33 are defined for each relay system as follows: That is, the angle between the incident ray entering each relay system from each scanner side and the optical axis of each relay system is defined as ωinR, and the angle between the emerging ray emerging from each relay system to the objective lens system side and the optical axis AX is defined as ωoutR, where MR = |ωoutR / ωinR|, and MR when the incident ray is a paraxial ray is defined as MRpar, and MR when the incident ray is the ray at the maximum angle of view is defined as MRmax.

[0193] <Explanation of the operation of the image processing device> Next, an example of the operation of the image processing device 17 when an ophthalmic apparatus is configured using an objective lens system having angular magnification distribution characteristics suitable for the UWF objective lens system described above will be described. Correction may be required when displaying an image using characteristic data regarding the angular magnification distribution of the objective lens system. An example of processing for this purpose will be described with reference to FIG. 43. The image display processing described below can be applied to both SLO images and OCT images.

[0194] For ease of explanation, the following description will be given assuming that the image display process is executed by the control device 16 shown in FIG. 1. For ease of explanation, the following description will be given assuming that the image processing device 17 is an ASIC (Application Specific Integrated Circuit). Note that, although an example of the image processing device 17 is implemented by an ASIC, the technology of the present disclosure is not limited to this. For example, the image processing device 17 may be other hardware resources such as an FPGA (Field Programmable Gate Array).

[0195] 43, the image processing device 17 sets a scanning range in accordance with an instruction received by the input / display device 16E in step 500. Here, the scanning range is a range set by, for example, upper and lower limit values ​​of the scanning angle in each of the X and Y directions.

[0196] In step 502, the CPU 16A identifies the current ω in. Note that ω in is uniquely identified from the current scanning angle of the scanner.

[0197] In step 504, the image processing device 17 obtains angular magnification distribution data of the objective lens system from a lookup table, and obtains data of the objective lens system at ωin specified in step 502. The lookup table is a table that associates the angle of view with data of the objective lens system, i.e., the correspondence between ωin and data of the objective lens system, and includes information about the angular magnification distribution. The angular magnification distribution data is data on the angular magnification M as a function of the angle of incidence ωin, which is the scanning angle of the scanner. Note that other data such as the amount of distortion as a function of ωin and peripheral light intensity as a function of ωin may also be obtained. Furthermore, these data may be design data or measurement data.

[0198] In step 506 , the image processing device 17 corrects the data based on the light reception results at the light receiving section based on the angular magnification distribution data of the objective lens system acquired in step 504 .

[0199] In step 508, the image processing device 17 generates an image based on the data corrected in step 506. In step 510, the input / display device 16E displays an image based on the data generated in step 508, and this image display process ends.

[0200] The image display process described above is merely an example. Therefore, it goes without saying that unnecessary steps may be deleted, new steps may be added, or the order of processing may be changed without departing from the spirit of the present invention. Furthermore, with regard to image processing related to distortion correction from detection data of a fundus image to fundus image formation as described above, there are related disclosures in U.S. Patent No. 9,039,183 and U.S. Patent No. 9,649,031, and International Publication No. WO 2014 / 096835, all of which are incorporated herein by reference.

[0201] In the above embodiment, the image display process is implemented by a software configuration using the CPU 16A and a hardware configuration using the image processing device 17, but the technology of the present disclosure is not limited to this. For example, the image display process may be implemented only by a software configuration using a computer.

[0202] Furthermore, in the above embodiment, an apparatus having the functions of both an SLO system and an OCT system was described, but it is also possible to apply the technology disclosed herein to configure an apparatus having the functions of only one of an SLO system and an OCT system.

[0203] All publications, patent applications, and technical standards mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent application, or technical standard was specifically and individually indicated to be incorporated by reference.

[0204] The following additional notes are provided regarding the above-described embodiment. (Appendix 1) An ophthalmic optical system, the ophthalmic optical system is configured to irradiate a light beam from a light source onto the subject's eye, The angle between the incident light beam incident on the ophthalmic optical system from the light source side and the optical axis of the ophthalmic optical system is defined as ωin, an angle formed between the optical axis and an emergent light ray emitted from the ophthalmic optical system toward the eye to be examined is defined as ωout; When M=|ωout / ωin| is defined in the ophthalmic optical system, M when the incident ray is a paraxial ray is Mpar, and When the incident light ray has the maximum angle of view, M is Mmax. Mpar <Mmax An ophthalmic optical system that satisfies the conditional expression shown below.

[0205] (Appendix 2) 1.1×Mpar <Mmax 10. An ophthalmic optical system according to claim 1, which satisfies the conditional expression:

[0206] (Appendix 3) Mmax < 2 × Mpar The ophthalmic optical system according to Appendix 1 or 2 that satisfies the conditional expression represented by

[0207] (Appendix 4) 1 < Mpar, and 1 < Mmax The ophthalmic optical system according to any one of Appendices 1 to 3 that satisfies the conditional expression represented by

[0208] (Appendix 5) The ophthalmic optical system according to any one of Appendices 1 to 4 that has a range where M increases as ωin increases between Mpar and Mmax.

[0209] (Appendix 6) The ophthalmic optical system according to any one of Appendices 1 to 5, wherein the ophthalmic optical system is a refractive optical system, and ωout when the incident light beam is a light beam with the maximum angular field is 50 degrees or more.

[0210] (Appendix 7) The ophthalmic optical system sequentially from the light source side, A meniscus-shaped lens component with a convex surface facing the light source side, A negative lens with a concave surface facing the light source side and the absolute value of the radius of curvature of the lens surface on the light source side being smaller than the absolute value of the radius of curvature of the lens surface on the eye to be examined side, A positive lens with a convex surface facing the eye to be examined side and the absolute value of the radius of curvature of the lens surface on the eye to be examined side being smaller than the absolute value of the radius of curvature of the lens surface on the light source side, A positive lens, A positive lens with a convex surface facing the eye to be examined side, A cemented lens in which a positive lens and a negative lens with convex surfaces facing the eye to be examined side are cemented together, A positive lens with a convex surface facing the light source side, and, A positive meniscus lens with a concave surface facing the eye to be examined side The ophthalmic optical system according to any one of Appendices 1 to 6, including

[0211] (Appendix 8) An ophthalmic optical system according to any one of Supplementary Note 1 to Supplementary Note 7; a scanning unit, The scanning unit is an ophthalmic device that is arranged at a pupil conjugate position that is conjugate with the pupil position of the test eye with respect to the ophthalmic optical system, causes a light beam emitted from the light source to enter the ophthalmic optical system, and scans the light beam emitted from the light source so that the test eye is scanned by the emitted light beam.

[0212] (Appendix 9) a light receiving unit that receives reflected light of the emitted light beam from the subject's eye; 9. The ophthalmologic apparatus according to claim 8, further comprising: an image processing device that corrects data based on a result of light reception at the light receiving unit based on M related to ωout.

[0213] (Appendix 10) 10. The ophthalmologic apparatus according to claim 9, wherein the image processing device generates an image of the subject's eye based on the corrected data.

[0214] (Appendix 11) An ophthalmic optical system, the ophthalmic optical system is configured to irradiate the subject's eye with a light beam scanned at a predetermined scanning angle, a maximum value of an angle formed between a light beam emitted from the ophthalmic optical system to the subject's eye and an optical axis of the ophthalmic optical system is defined as ωmax; a beam diameter of the emergent beam in the scanning direction at the pupil position of the subject's eye when the angle between the emergent beam and the optical axis is ω is defined as Pmax; When the angle between the emitted light beam and the optical axis is minimum, the light beam diameter in the scanning direction of the emitted light beam at the pupil position of the eye to be examined is Pmin, Pmax <Pmin×0.7 / (cos(ωmax)) An ophthalmic optical system that satisfies the conditional expression shown below.

[0215] (Appendix 12) Pmax <Pmin 12. An ophthalmic optical system according to claim 11, which satisfies the conditional expression:

[0216] (Appendix 13) 0.2×Pmin <Pmax 13. An ophthalmic optical system according to claim 11 or 12, which satisfies the conditional expression:

[0217] (Appendix 14) 14. The ophthalmic optical system according to any one of claims 11 to 13, wherein the ophthalmic optical system is a refractive optical system, and an angle formed between the exiting light beam and the optical axis when the incident light beam is a light beam with a maximum angle of view is 50 degrees or more.

[0218] (Appendix 15) the ophthalmic optical system is configured to irradiate the subject's eye with a light beam from a light source, The ophthalmic optical system includes, in order from the light source side, a meniscus-shaped lens component with a convex surface facing the light source; a negative lens having a concave surface facing the light source side and having an absolute value of the radius of curvature of the lens surface on the light source side smaller than the absolute value of the radius of curvature of the lens surface on the test eye side; a positive lens having a convex surface facing the subject's eye and having an absolute value of the radius of curvature of the lens surface facing the subject's eye smaller than the absolute value of the radius of curvature of the lens surface facing the light source; Positive lens, a positive lens having a convex surface facing the eye to be examined; a cemented lens in which a positive lens and a negative lens are cemented together, the positive lens having a convex surface facing the eye to be examined; a positive lens having a convex surface facing the light source; and a positive meniscus lens with a concave surface facing the eye to be examined; 15. The ophthalmic optical system according to any one of Supplementary Note 11 to Supplementary Note 14, comprising:

[0219] (Appendix 16) An ophthalmic optical system according to any one of Supplementary Note 11 to Supplementary Note 15; a scanning unit, The scanning unit is an ophthalmic device that is arranged at a pupil conjugate position that is conjugate with the pupil position of the test eye with respect to the ophthalmic optical system, causes a light beam emitted from a light source to enter the ophthalmic optical system, and scans the light beam emitted from the light source so that the test eye is scanned by the light beam emitted from the ophthalmic optical system.

[0220] (Appendix 17) 1. An ophthalmic device comprising: A light source and an ophthalmic optical system that irradiates the subject's eye with light from the light source, The angle between the incident light beam incident on the ophthalmic optical system from the light source side and the optical axis of the ophthalmic optical system is defined as ωin, an angle formed between the optical axis and an emergent light ray emitted from the ophthalmic optical system toward the eye to be examined is defined as ωout; When M=|ωout / ωin| is defined in the ophthalmic optical system, M when the incident ray is a paraxial ray is Mpar, and When the incident light ray has the maximum angle of view, M is Mmax. Mpar <Mmax An ophthalmic apparatus that satisfies the conditional expression shown below.

[0221] (Appendix 18) a first scanning unit capable of scanning the first light beam at a predetermined maximum scanning angle; a first objective optical system that outputs the first light flux incident from the first scanning unit to the subject's eye and makes the position of the first scanning unit and the pupil position of the subject's eye conjugate with each other; a second scanning unit capable of scanning a second light beam different from the first light beam at a maximum scanning angle smaller than the maximum scanning angle of the first scanning unit; a second objective optical system that outputs the second light beam incident from the second scanning unit to the subject's eye and makes the position of the second scanning unit and the pupil position of the subject's eye conjugate with each other; a combining unit that is disposed on an optical path between the first scanning unit and the eye to be examined and an optical path between the second scanning unit and the eye to be examined, and combines an optical path of the first light beam directed toward the eye to be examined and an optical path of the second light beam directed toward the eye to be examined, the first objective optical system and the second objective optical system have a common optical system located closer to the subject's eye than the combining unit; The paraxial angular magnification of the first objective optical system from the first scanning unit to the eye to be examined is M1, and When the paraxial angular magnification of the second objective optical system from the second scanning unit to the subject's eye is M2, |M1|<|M2| An ophthalmic apparatus that satisfies the conditional expression shown below.

[0222] (Appendix 19) the first objective optical system is for a scanning laser ophthalmoscope, and the second objective optical system is for an optical coherence tomography system; 1.5<|M1|<3.5, and 2.5<|M2|<5 19. The ophthalmic apparatus according to claim 18, which satisfies the conditional expression:

[0223] (Appendix 20) 20. The ophthalmologic apparatus according to claim 18, wherein a scanning speed at which the second scanning unit scans the second light beam is slower than a scanning speed at which the first scanning unit scans the first light beam.

[0224] (Appendix 21) The common optical system includes, in order from the combining unit side to the eye to be examined, a positive lens having a convex surface facing the eye to be examined; a cemented lens in which a positive lens having a convex surface facing the eye to be examined and a negative lens are cemented together; a positive lens having a convex surface facing the combining portion; and a positive meniscus lens with a concave surface facing the eye to be examined; 21. The ophthalmic apparatus of any one of claims 18 to 20, comprising:

[0225] (Appendix 22) The optical system of the first objective optical system located closer to the first scanning unit than the combining unit is configured as follows, in order from the first scanning unit side to the eye to be examined: a meniscus-shaped lens component with a convex surface facing the first scanning unit; a negative lens having a concave surface facing the first scanning unit side and having an absolute value of the radius of curvature of the lens surface on the first scanning unit side smaller than the absolute value of the radius of curvature of the lens surface on the test eye side; a positive lens having a convex surface facing the subject's eye and having an absolute value of the radius of curvature of the lens surface facing the subject's eye smaller than the absolute value of the radius of curvature of the lens surface facing the first scanning unit; and Positive lens 22. The ophthalmic apparatus of any one of Supplementary Notes 18 to 21, comprising:

[0226] (Appendix 23) The optical system of the second objective optical system located on the second scanning unit side from the combining unit is configured as follows, in order from the second scanning unit side to the eye to be examined: a meniscus-shaped lens component with a convex surface facing the second scanning unit; a negative lens having a concave surface facing the second scanning unit side and having an absolute value of the radius of curvature of the lens surface on the second scanning unit side smaller than the absolute value of the radius of curvature of the lens surface on the test eye side; a positive lens having a convex surface facing the subject's eye and having an absolute value of the radius of curvature of the lens surface facing the subject's eye smaller than the absolute value of the radius of curvature of the lens surface facing the second scanning unit; and Positive lens 23. The ophthalmic apparatus of any one of claims 18 to 22, comprising:

[0227] (Appendix 24) a first scanning unit capable of scanning the first light beam at a predetermined maximum scanning angle; a first objective optical system that outputs the first light flux incident from the first scanning unit to the subject's eye and makes the position of the first scanning unit and the pupil position of the subject's eye conjugate with each other; a second scanning unit capable of scanning a second light beam different from the first light beam at a maximum scanning angle smaller than the maximum scanning angle of the first scanning unit; a second objective optical system that outputs the second light beam incident from the second scanning unit to the subject's eye and makes the position of the second scanning unit and the pupil position of the subject's eye conjugate with each other; a combining unit that is disposed on an optical path between the first scanning unit and the eye to be examined and an optical path between the second scanning unit and the eye to be examined, and combines an optical path of the first light beam directed toward the eye to be examined and an optical path of the second light beam directed toward the eye to be examined, the first objective optical system and the second objective optical system have a common optical system located closer to the subject's eye than the combining unit; The paraxial lateral magnification of the first objective optical system from the first scanning unit to the eye to be examined is β1, and When the paraxial lateral magnification of the second objective optical system from the second scanning unit to the subject's eye is β2, |β2|<|β1| An ophthalmic apparatus that satisfies the conditional expression shown below.

[0228] (Appendix 25) the first optical system is for a scanning laser ophthalmoscope, and the second optical system is for an optical coherence tomography system; 0.25<|β1|<0.7, and 0.2<|β2|<0.4 25. The ophthalmic apparatus according to claim 24, which satisfies the conditional expression:

[0229] (Appendix 26) 26. The ophthalmologic apparatus according to claim 24, wherein a scanning speed at which the second scanning unit scans the second light beam is slower than a scanning speed at which the first scanning unit scans the first light beam.

[0230] (Appendix 27) a first scanning unit that scans the first light beam at a predetermined scanning speed; a first objective optical system that outputs the first light flux incident from the first scanning unit to the subject's eye and makes the position of the first scanning unit and the pupil position of the subject's eye conjugate with each other; a second scanning unit that scans with a second light beam different from the first light beam at a scanning speed slower than the scanning speed of the first scanning unit; a second objective optical system that outputs the second light beam incident from the second scanning unit to the subject's eye and makes the position of the second scanning unit and the pupil position of the subject's eye conjugate with each other; An optical path synthesizing unit is disposed in an optical path between the first scanning unit and the eye to be examined and in an optical path between the second scanning unit and the eye to be examined, and synthesizes an optical path of the first light beam traveling toward the eye to be examined and an optical path of the second light beam traveling toward the eye to be examined. The first objective optical system and the second objective optical system have a common optical system on the eye to be examined side of the synthesizing unit. When the paraxial angular magnification of the first objective optical system from the first scanning unit to the eye to be examined is M1, and when the paraxial angular magnification of the second objective optical system from the second scanning unit to the eye to be examined is M2, |M1| < |M2| An ophthalmic apparatus satisfying the conditional expression represented by this.

[0231] (Appendix 28) An ophthalmic optical system configured to irradiate an angle-scanned light beam toward the eye to be examined, (1) Let ωin be the angle formed by the incident light beam to the ophthalmic optical system and the optical axis of the ophthalmic optical system, (2) Let ωout be the angle formed by the emitted light beam from the ophthalmic optical system toward the eye to be examined and the optical axis, (3) M is defined as M = |ωout / ωin|, Let Mpar be M when the incident light beam is a paraxial light beam, When Mmax is M when the incident light beam is the maximum angle light beam of ωin, Mpar < Mmax An ophthalmic optical system satisfying the conditional expression represented by this.

[0232] (Appendix 29) 1.1 × Mpar < Mmax <00012�7>The ophthalmic optical system according to Appendix 28, satisfying the conditional expression represented by this.

[0233] (Appendix 30) Mmax < 2 × Mpar The ophthalmic optical system according to Appendix 28, satisfying the conditional expression represented by this.

[0234] (Appendix 31) 1 < Mpar, and 1 < Mmax 29. An ophthalmic optical system according to claim 28, which satisfies the conditional expression:

[0235] (Appendix 32) 1.5 <Mpar<5.0 32. An ophthalmic optical system according to any one of claims 28 to 31, which satisfies the conditional expression shown below.

[0236] (Appendix 33) 33. The ophthalmic optical system according to any one of claims 28 to 32, wherein M increases as ωin increases within the range from Mpar to Mmax.

[0237] (Appendix 34) 34. The ophthalmic optical system according to any one of claims 28 to 33, wherein the ophthalmic optical system is a refractive optical system.

[0238] (Appendix 35) Starting from the opposite side of the eye to be examined, a meniscus lens component having a concave surface facing the eye to be examined; a negative lens having a concave surface facing the opposite side of the subject's eye; a positive lens having a convex surface facing the eye to be examined; Positive lens, a positive lens having a convex surface facing the eye to be examined; cemented lenses, a positive lens having a convex surface facing the opposite side of the subject's eye; and a positive meniscus lens with a concave surface facing the eye to be examined; 35. The ophthalmic optical system according to any one of appendices 28 to 34, comprising:

[0239] (Appendix 36) An ophthalmic optical system according to any one of Supplementary Notes 28 to 35, and a scanning unit disposed at a position conjugate with a pupil position of the subject's eye with respect to the ophthalmic optical system; Equipped with The scanning unit causes the light beam to enter the ophthalmic optical system and scans the light beam at an angle ωin.

[0240] (Appendix 37) 37. The ophthalmic apparatus according to claim 36, wherein when the incident light beam is a light beam with a maximum angle of view, ωout is 50 degrees or more.

[0241] (Appendix 38) a light receiving unit that receives reflected light from the subject's eye; an image processing unit that corrects data relating to the light receiving result of the light receiving unit based on M relating to ωin controlled by the scanning unit; 38. The ophthalmic apparatus according to claim 36 or 37, further comprising:

[0242] (Appendix 39) 39. The ophthalmologic apparatus according to claim 38, wherein the image processing unit generates an image of the subject's eye based on the corrected data.

[0243] (Appendix 40) An ophthalmic optical system configured to irradiate an angle scanning light beam onto an eye to be examined, (1) The maximum angle formed by the light beam emitted from the ophthalmic optical system and the optical axis of the ophthalmic optical system is defined as ωmax, (2) When the angle between the emitted light beam and the optical axis is ωmax, the diameter of the emitted light beam in the meridional direction at the pupil position of the eye to be examined is Pmax, (3) When the diameter of the emitted light beam in the meridional direction at the pupil position of the eye to be examined when the angle between the emitted light beam and the optical axis is minimum is Pmin, Pmax <Pmin×0.7 / (cos(ωmax)) An ophthalmic optical system that satisfies the conditional expression shown below.

[0244] (Appendix 41) Pmax <Pmin 41. An ophthalmic optical system according to claim 40, which satisfies the conditional expression:

[0245] (Appendix 42) 0.2×Pmin <Pmax 41. An ophthalmic optical system according to claim 40, which satisfies the conditional expression:

[0246] (Appendix 43) 43. The ophthalmic optical system according to any one of appendices 40 to 42, wherein the ophthalmic optical system is a refractive optical system.

[0247] (Appendix 44) An ophthalmic optical system according to any one of Supplementary Notes 40 to 43, and A scanning unit is provided, the scanning unit is disposed at a position conjugate with the pupil position of the subject's eye with respect to the ophthalmic optical system, the scanning unit causes a light beam to be incident on the ophthalmic optical system within a predetermined scanning angle range; The scanning unit is an ophthalmic apparatus configured to scan the light beam emitted from the ophthalmic optical system so as to scan the eye to be examined.

[0248] (Appendix 45) 45. The ophthalmic apparatus according to claim 44, wherein when the light beam incident on the ophthalmic optical system is a light beam with a maximum angle of view, the angle formed between the exiting light beam reaching the subject's eye and the optical axis is 50 degrees or more.

[0249] (Appendix 46) An ophthalmic optical system configured to irradiate an angle scanning light beam to a subject's eye, (1) The angle between the incident light beam on the ophthalmic optical system and the optical axis of the ophthalmic optical system is defined as ωin, (2) the angle between the light ray emitted from the ophthalmic optical system toward the eye to be examined and the optical axis is defined as ωout; (3) M is defined as M=|ωout / ωin|, M at the center of the subject's eye to be scanned, including the intersection with the optical axis, is defined as Mc, When M in the peripheral part of the subject's eye to be scanned is Mp, Mc <Mp An ophthalmic optical system that satisfies the conditional expression shown below.

[0250] (Appendix 47) 1. An ophthalmic objective configured to transition an incident light beam to an exiting light beam, comprising: The angle of the incident light ray relative to the optical axis is defined as ω in , The angle of the exit ray with respect to the optical axis is defined as ωout, M is defined as M=|ωout / ωin|, When the incident ray is a paraxial ray, M is defined as Mpar, When the incident light ray is a light ray with the maximum angle of view, M is Mmax. Mpar <Mmax An ophthalmic objective lens comprising a plurality of lenses arranged along the optical axis so as to satisfy the condition:

[0251] (Appendix 48) 1. An ophthalmic objective configured to transfer an incident light beam to an exit light beam, comprising: the maximum angle formed by the light beam emitted from the ophthalmic objective lens and the optical axis is defined as ωmax; When the angle between the emitted light beam and the optical axis is ωmax, a meridional diameter of the emitted light beam intersecting a plane perpendicular to the optical axis at a position where the emitted light beam intersects the optical axis is defined as Pmax, When the angle between the emitted light beam from the ophthalmic objective lens and the optical axis is minimum, the diameter of the emitted light beam in the meridional direction intersecting with the surface is defined as Pmin, Pmax <Pmin×0.7 / (cos(ωmax)) An ophthalmic objective lens comprising a plurality of lenses arranged along the optical axis so as to satisfy the condition:

[0252] (Appendix 49) an objective lens for guiding light from a light source to the subject's eye; TL is the distance on the optical axis from the lens surface of the objective lens closest to the light source to the lens surface of the objective lens closest to the eye to be examined, When the focal length of the objective lens is f, -1 <TL / f<1 An ophthalmic optical system that satisfies the conditional expression shown below.

[0253] (Appendix 50) the objective lens comprises a front group having positive refractive power and a rear group having positive refractive power arranged on the subject's eye side of the front group, the front group and the rear group are separated by the largest air gap on the optical axis between lens surfaces of the objective lens, The focal length of the front group is fF, If the focal length of the rear group is fR, 1 <fF / fR<4 49. An ophthalmic optical system according to claim 49, which satisfies the condition:

[0254] (Appendix 51) the objective lens comprises a front group having positive refractive power and a rear group having positive refractive power arranged on the subject's eye side of the front group, the front group and the rear group are separated by the largest air gap on the optical axis between lens surfaces of the objective lens, If the maximum air gap is D, 0.1 <D / TL<0.5 51. An ophthalmic optical system according to claim 49 or 50, which satisfies the conditional expression:

[0255] (Appendix 52) the rear group includes an A group having a positive refractive power and a B group having a positive refractive power and disposed on the subject's eye side of the A group, the group A includes at least one cemented lens having positive refractive power, and the lens surface of the lens in the group A closest to the eye to be examined is a convex or flat surface, the group B is composed of one or more positive meniscus lens components with a concave surface facing the eye to be examined, The focal length of the B group is fB, If the focal length of the rear group is fR, 0.4 <fB / fR<2.5 52. An ophthalmic optical system according to claim 50 or 51, which satisfies the conditional expression shown below.

[0256] (Appendix 53) When the focal length of the positive lens constituting the cemented lens included in the group A is fAp, All the positive lenses in all the cemented lenses included in the group A are 0.9 <fAp / fR<3.7 53. An ophthalmic optical system according to claim 52, which satisfies the conditional expression:

[0257] (Appendix 54) 54. The ophthalmic optical system according to any one of claims 49 to 53, wherein an angle formed between an emergent light ray emerging from the objective lens toward the subject's eye and an optical axis of the objective lens is 50 degrees or more.

[0258] (Appendix 55) 54. The ophthalmic optical system according to any one of claims 50 to 53, wherein the front group has a lens surface with negative refractive power and a lens surface with positive refractive power arranged on the subject's eye side of the lens surface with negative refractive power.

[0259] (Appendix 56) 56. The ophthalmic optical system according to claim 55, wherein the front group has a positive meniscus lens having a convex surface facing the eye to be examined.

[0260] (Appendix 57) The ophthalmic optical system according to any one of claims 50 to 53, wherein the front group has a meniscus lens with a concave surface facing the test eye side, and further has a negative lens and a positive lens on the test eye side of the meniscus lens.

[0261] (Appendix 58) The ophthalmic optical system according to any one of appendices 50 to 52, wherein the front group has a negative lens and a positive lens arranged on the test eye side of the negative lens, and an air lens with negative refractive power is formed between the negative lens and the positive lens.

[0262] (Appendix 59) 59. The ophthalmic optical system according to claim 58, wherein the negative lens and the positive lens are arranged with their concave surfaces facing each other.

[0263] (Appendix 60) 60. The ophthalmic optical system according to claim 59, wherein the front group further includes a meniscus lens arranged on the opposite side of the negative lens from the eye to be examined, with its concave surface facing the eye to be examined, and a positive lens arranged on the eye to be examined from the positive lens.

[0264] (Appendix 61) 54. The ophthalmic optical system according to claim 52, wherein the group A has one or more cemented lenses.

[0265] (Appendix 62) 54. The ophthalmic optical system according to claim 52, wherein the group A has two or more cemented lenses.

[0266] (Appendix 63) 54. The ophthalmic optical system according to claim 52 or 53, wherein the group B includes one or more single lenses having a positive meniscus shape.

[0267] (Appendix 64) 54. The ophthalmic optical system according to claim 52 or 53, wherein the group B is composed of only one or more single lenses having a positive meniscus shape.

[0268] (Appendix 65) a first scanning unit configured to emit a first scanning light beam at a first maximum scanning angle; a first optical system configured to form an SLO system, having a common lens group, and configured to make the first scanning unit and a pupil of the subject's eye have a first conjugate relationship and emit the first scanning light beam to the subject's eye via the common lens group; a second scanning unit configured to emit a second scanning light beam and having a second maximum scanning angle smaller than the first maximum scanning angle of the first scanning unit; a second optical system configured to form an OCT system, having the common lens group, and configured to make the second scanning unit and the pupil of the subject's eye have a second conjugate relationship and emit the second scanning light beam to the subject's eye via the common lens group; a combining unit configured to combine an optical path of the first optical system and an optical path of the second optical system, the combining unit being disposed between the first scanning unit and the common lens group, and similarly disposed between the second scanning unit and the common lens group; Equipped with (1) the paraxial angular magnification of the first optical system to the pupil of the subject's eye regarding the first conjugate relationship is M1; (2) When the paraxial angular magnification of the second optical system to the pupil of the subject's eye regarding the second conjugate relationship is M2, |M1|<|M2| An ophthalmic apparatus that satisfies the conditional expression shown below.

[0269] (Appendix 66) 1.5<|M1|<3.5, and 2.5<|M2|<5 66. An ophthalmic apparatus according to claim 65, which satisfies the conditional expression:

[0270] (Appendix 67) 66. The ophthalmic apparatus according to claim 65, wherein the second scanning unit scans the second scanning light beam at a scanning speed slower than the scanning speed at which the first scanning unit scans the first scanning light beam.

[0271] (Appendix 68) The common lens group is arranged in the following order from the combining unit side to the eye to be examined: a positive lens having a convex surface facing the eye to be examined; cemented lenses, a positive lens having a convex surface facing the combining portion; and a positive meniscus lens with a concave surface facing the eye to be examined; 68. The ophthalmologic apparatus according to any one of claims 65 to 67, comprising:

[0272] (Appendix 69) the first optical system includes a first lens group on the first scanning unit side with respect to the combining unit, The first lens group is arranged in the following order from the first scanning unit side to the eye to be examined: a meniscus-shaped lens component with a convex surface facing the first scanning unit; a negative lens having a concave surface facing the first scanning unit; a positive lens having a convex surface facing the eye to be examined; and Positive lens 69. The ophthalmologic apparatus according to any one of appendices 65 to 68, comprising:

[0273] (Appendix 70) the second optical system includes a second lens group on the second scanning unit side with respect to the combining unit, The second lens group is arranged in the following order from the second scanning unit side to the eye to be examined: a meniscus-shaped lens component with a convex surface facing the second scanning unit; a negative lens having a concave surface facing the second scanning unit; a positive lens having a convex surface facing the eye to be examined; and Positive lens 70. The ophthalmologic apparatus according to any one of claims 65 to 69, comprising:

[0274] (Appendix 71) a first scanning unit configured to emit a first scanning light beam at a first maximum scanning angle; a first optical system configured to form an SLO system, having a common lens group, and configured to make the first scanning unit and a pupil of the subject's eye have a first conjugate relationship and emit the first scanning light beam to the subject's eye via the common lens group; a second scanning unit configured to emit a second scanning light beam and having a second maximum scanning angle smaller than the first maximum scanning angle of the first scanning unit; a second optical system configured to form an OCT system, having the common lens group, and configured to make the second scanning unit and the pupil of the subject's eye have a second conjugate relationship and emit the second light beam to the subject's eye via the common lens group; a combining unit configured to combine an optical path of the first optical system and an optical path of the second optical system, the combining unit being disposed between the first scanning unit and the common lens group, and similarly disposed between the second scanning unit and the common lens group; Equipped with (1) The paraxial lateral magnification of the first optical system from the first scanning unit to the subject's eye is defined as β1, (2) When the paraxial lateral magnification of the second optical system from the second scanning unit to the subject's eye is β2, |β2|<|β1| An ophthalmic apparatus that satisfies the conditional expression shown below.

[0275] (Appendix 72) 0.25<|β1|<0.7, and 0.2<|β2|<0.4 72. An ophthalmic apparatus according to claim 71, which satisfies the conditional expression:

[0276] (Appendix 73) 72. The ophthalmic apparatus according to claim 71, wherein the second scanning unit scans the second scanning light beam at a scanning speed slower than the scanning speed at which the first scanning unit scans the first scanning light beam.

[0277] (Appendix 74) a first scanning unit configured to scan a first scanning light beam at a first scanning speed; a first optical system configured to form an SLO system, having a common lens group, and configured to make the first scanning unit and a pupil of the subject's eye have a first conjugate relationship and emit the first scanning light beam to the subject's eye via the common lens group; a second scanning unit configured to scan a second scanning light beam different from the first light beam at a second scanning speed slower than the first scanning speed of the first scanning unit; a second optical system configured to form an OCT system, having the common lens group, and configured to make the second scanning unit and the pupil of the subject's eye have a second conjugate relationship and emit the second scanning light beam to the subject's eye via the common lens group; a combining unit configured to combine an optical path of the first optical system and an optical path of the second optical system, the combining unit being disposed between the first scanning unit and the common lens group, and similarly disposed between the second scanning unit and the common lens group; Equipped with (1) the paraxial angular magnification of the first optical system to the pupil of the subject's eye regarding the first conjugate relationship is M1; (2) When the paraxial angular magnification of the second optical system to the pupil of the subject's eye regarding the second conjugate relationship is M2, |M1|<|M2| An ophthalmic apparatus that satisfies the conditional expression shown below.

[0278] (Appendix 75) a first scanning unit configured to emit a first scanning light beam in a first scanning angle range; a first optical system configured to form an SLO system, having a common lens group, and configured to make the first scanning unit and a pupil of the subject's eye have a first conjugate relationship and emit the first scanning light beam to the subject's eye at a first external illumination angle Θ1 through the common lens group; a second scanning unit configured to emit a second scanning light beam in a second scanning angle range smaller than the first scanning angle range; a second optical system configured to form an OCT system, having the common lens group, and configured to make the second scanning unit and the pupil of the subject's eye have a second conjugate relationship and emit the second scanning light beam to the subject's eye at a second external illumination angle Θ2 through the common lens group; a combining unit configured to combine an optical path of the first optical system and an optical path of the second optical system, the combining unit being disposed between the first scanning unit and the common lens group, and similarly disposed between the second scanning unit and the common lens group; Equipped with Θ1=Θ2 An ophthalmic apparatus that satisfies the conditional expression shown below.

[0279] (Appendix 76) 76. The ophthalmic apparatus according to claim 75, wherein the first external irradiation angle Θ1 and the second external irradiation angle Θ2 are both 100 degrees or greater.

[0280] (Appendix 77) the first optical system includes a first relay system that forms a relay conjugate position that has a third conjugate relationship with the first scanning unit in an optical path between the combining unit and the subject's eye, 77. The ophthalmologic apparatus according to any one of claims 65 to 76, wherein the second optical system has a second relay system that establishes a fourth conjugate relationship between the second scanning unit and the relay conjugate position.

[0281] (Appendix 78) Further, a third scanning unit is disposed at the relay conjugate position, 78. The ophthalmologic apparatus according to claim 77, wherein a scanning direction of the third scanning unit is perpendicular to a scanning direction of the first scanning unit and a scanning direction of the second scanning unit.

[0282] (Appendix 79) MR1 is the paraxial angular magnification of the first relay system to the relay conjugate position with respect to the third conjugate relationship; When the paraxial angular magnification of the second relay system to the relay conjugate position regarding the fourth conjugate relationship is MR2, |MR1|<|MR2| 79. The ophthalmic apparatus according to claim 77 or 78, which satisfies the conditional expression shown below.

[0283] (Appendix 80) |MR1|=1 79. An ophthalmic apparatus according to claim 79, which satisfies the conditional expression:

[0284] (Appendix 81) |MR2|>1 79. An ophthalmic apparatus according to claim 79, which satisfies the conditional expression:

[0285] (Appendix 82) the first relay system includes, in order from the first scanning unit side, a first sub-lens group and a common sub-lens group included in the common lens group, the second relay system has, in order from the second scanning unit, a second sub-lens group and the common sub-lens group, The ophthalmic device according to any one of claims 77 to 81, wherein the synthesis unit is arranged between the first sub-lens group and the common sub-lens group, and between the second sub-lens group and the common sub-lens group.

[0286] (Appendix 83) the first scanning light beam passing between the first sub-lens group and the common sub-lens group is a parallel light beam, 83. The ophthalmic apparatus of claim 82, wherein the second scanning light beam passing between the second sub-lens group and the common sub-lens group is a parallel light beam.

[0287] (Appendix 84) the first relay system includes, in order from the first scanning unit side, a first sub-lens group and a common sub-lens group included in the common lens group, the first sub-lens group has a positive meniscus lens with a concave surface facing the first scanning unit side and a meniscus-shaped lens component with a convex surface facing the first scanning unit side, 81. The ophthalmic apparatus according to claim 80, wherein the first sub-lens group and the common sub-lens group are configured symmetrically with respect to a plane perpendicular to the optical axis.

[0288] (Appendix 85) 83. The ophthalmic device of claim 82, wherein the second sub-lens group has at least one positive lens and at least one negative lens, and has concave lens surfaces facing each other and separated by an air gap.

[0289] (Appendix 86) the common lens group includes the common secondary lens group and an objective lens arranged closer to the subject's eye than the relay conjugate position, An ophthalmic device according to any one of Appendices 82 to 85, wherein the objective lens has, in order from the relay conjugate position side, a front group having positive refractive power and a rear group having positive refractive power separated from the front group by the maximum air gap on the optical axis between lens surfaces in the objective lens.

[0290] (Appendix 87) 87. The ophthalmic apparatus according to claim 86, wherein the front group has, in order from the relay conjugate position side, a positive lens and a negative lens.

[0291] (Appendix 88) 88. The ophthalmic apparatus according to claim 86, wherein the rear group includes, in order from the relay conjugate position side, a cemented lens having positive refractive power, a positive lens, and a positive meniscus lens with a concave surface facing the subject's eye. [Explanation of symbols]

[0292] 12 Examined eye 19. Photographing optical system 22, 622 First Optical Scanner 24,624 Second optical scanner 26,626 Synthesis section 27 Pupil 28 common lens group 30 Wide-angle optical system 31 SLO objective lens system 32 OCT objective lens system 110 Ophthalmological equipment 300, 600 objective lens system 601 1st Relay System 602 Second Relay System 625 3rd Optical Scanner AX optical axis G1 First lens group G2 Second lens group G3 3rd lens group GF front group GR rear group GRA Group A GRB group B Pr Relay conjugate position RG1 First secondary lens group RG2 Second sub-lens group RG3 common secondary lens group

Claims

[Claim 1] a light source for providing light; an ophthalmic optical system configured to irradiate the light from the light source onto the subject's eye; a scanning unit that is arranged at a position conjugate with a position corresponding to a pupil position of the subject's eye with respect to the ophthalmic optical system, and that scans the light from the light source angularly to scan the light irradiated onto the subject's eye; a light receiving unit that receives reflected light from the subject's eye via the ophthalmic optical system and the scanning unit; an image processing unit that forms an image of the subject's eye based on information from the light receiving unit and information from the scanning unit; Including, The ophthalmic optical system comprises: an angle formed between an incident light ray incident on the ophthalmic optical system from the light source side by the scanning unit and an optical axis of the ophthalmic optical system is defined as ωin; an angle formed between the optical axis and an emergent light ray emitted from the ophthalmic optical system toward the subject's eye is defined as ωout; In the ophthalmic optical system, M is defined as M=|ωout / ωin|, M when the incident ray is a paraxial ray is Mpar, and When the incident light beam is the maximum angle light beam of ωin, M is Mmax. Mpar<Mmax The value of M is distributed so as to satisfy the conditional expression The image processing unit corrects data relating to the light reception result of the light receiving unit based on a distribution of the value of M relating to the incident angle ωin scanned by the scanning unit. Ophthalmology equipment.

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