Ophthalmologic apparatus

Abstract

To provide a new technique to acquire a higher quality image of an eye to be examined.SOLUTION: An ophthalmologic apparatus includes two or more curved mirrors, an illumination optical system, and an imaging optical system. The illumination optical system includes a slit formed with an opening configured to be disposed at a fundus conjugate position substantially optically conjugate with the fundus of the eye to be examined, and irradiates the fundus with slit-shaped illumination light generated by irradiating the slit with light from a light source through the two or more curved mirrors. The imaging optical system is configured to be disposed at the fundus conjugate position, and includes an image sensor that receives return light from the eye to be examined through the two or more curved mirrors. The opening is formed such that a width in a lateral direction varies depending on a position in a longitudinal direction.SELECTED DRAWING: Figure 11

Description

[Technical Field]

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

[0002] Ophthalmic devices used for screening and treating eye diseases are required to be able to easily capture (observe) images of the fundus of a subject's eye over a wide field of view. Specifically, there is a demand for devices that can capture images of the fundus of a subject's eye over a wide field of view of over 80 degrees in a single capture. A known example of such an ophthalmic device is a scanning laser ophthalmoscope (SLO). An SLO is a device that scans the fundus with light and forms an image of the fundus by detecting the returned light with a light-receiving device.

[0003] For example, Patent Document 1 discloses a scanning ophthalmoscope that uses a polygonal mirror and a plane mirror to perform two-dimensional parallel light scanning, and that can scan the retina at a wide angle by moving the scanning movement means to the eye to be examined.

[0004] For example, Patent Documents 2 and 3 disclose fundus imaging devices that can acquire high-contrast images with a simple configuration by combining a fundus scan using slit-shaped illumination light with a rolling shutter method. In particular, Patent Document 3 discloses a method for acquiring a wide-angle fundus image of a subject's eye by scanning the fundus of the subject's eye with slit-shaped illumination light via two elliptical concave mirrors.

[0005] For example, Patent Document 4 discloses a method of scanning the retina with light using a projection diaphragm formed so that the width of the aperture at the periphery is wider than the width of the aperture at the optical axis, in order to maximize the light output of an illuminator that has a shortage of light in the peripheral region. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Special Publication No. 2009-543585 [Patent Document 2] US Patent No. 7,831,106 [Patent Document 3] International Publication No. 2022 / 124170 [Patent Document 4] Special Publication No. 2017-526474 Summary of the Invention [Problem to be solved by the invention]

[0007] However, when slit-shaped illumination light is incident on the test eye at a wide angle via a curved mirror, the slit image of the illumination light at the shooting site is deformed, causing uneven illumination in the peripheral area of ​​the shooting site, which reduces the image quality of the wide-angle image of the test eye.

[0008] The present invention has been made in view of the above circumstances, and one of its objects is to provide a new technique for acquiring a higher quality image of an eye to be examined. [Means for solving the problem]

[0009] One aspect of some embodiments is an ophthalmologic device including: an illumination optical system including two or more curved mirrors; a slit having an opening formed therein configured to be positioned at a fundus conjugate position that is approximately optically conjugate with the fundus of the subject's eye; the illumination optical system irradiating the slit with light from a light source to generate slit-shaped illumination light, and irradiating the fundus via the two or more curved mirrors; and an imaging optical system including an image sensor configured to be positioned at the fundus conjugate position and receiving return light from the subject's eye via the two or more curved mirrors, wherein the opening is formed so that its width in the short direction varies depending on its position in the long direction. [Effects of the Invention]

[0010] According to the present invention, a new technique for acquiring a higher quality image of an eye to be examined can be provided. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram illustrating an example of the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 2] 1 is a schematic diagram for explaining the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 3A] 1 is a schematic diagram for explaining the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 3B] 1 is a schematic diagram for explaining the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 4A] 1 is a schematic diagram for explaining the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 4B] 1 is a schematic diagram for explaining the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 5] 1 is a schematic diagram for explaining the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 6A] 1 is a schematic diagram for explaining the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 6B] 1 is a schematic diagram for explaining the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 7] 1 is a schematic diagram illustrating an example of the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 8A] FIG. 10 is a schematic diagram for explaining a slit according to a comparative example of the embodiment. [Figure 8B] FIG. 10 is a schematic diagram for explaining a slit according to a comparative example of the embodiment. [Figure 9A] FIG. 10 is a schematic diagram for explaining a slit according to a comparative example of the embodiment. [Figure 9B] FIG. 10 is a schematic diagram for explaining a slit according to a comparative example of the embodiment. [Figure 10] FIG. 10 is a schematic diagram for explaining a slit according to a comparative example of the embodiment. [Figure 11] FIG. 4 is a schematic diagram for explaining a slit according to the embodiment. [Figure 12A] FIG. 4 is a schematic diagram for explaining a slit according to the embodiment. [Figure 12B] FIG. 4 is a schematic diagram for explaining a slit according to the embodiment. [Figure 13] 1 is a schematic diagram illustrating an example of the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 14] 1 is a schematic diagram illustrating an example of the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 15] 1 is a schematic diagram for explaining the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 16] 1 is a schematic diagram for explaining the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 17] 1 is a schematic diagram illustrating an example of the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 18] 1 is a schematic diagram for explaining the configuration of an optical system of an ophthalmologic apparatus according to an embodiment. [Figure 19] FIG. 2 is a schematic diagram illustrating an example of the configuration of a control system of an ophthalmologic apparatus according to an embodiment. [Figure 20] FIG. 2 is a schematic diagram illustrating an example of the configuration of a control system of an ophthalmologic apparatus according to an embodiment. [Figure 21] FIG. 4 is a flowchart showing an example of the operation of the ophthalmologic apparatus according to the embodiment. [Figure 22] FIG. 4 is a flowchart showing an example of the operation of the ophthalmologic apparatus according to the embodiment. [Figure 23] FIG. 4 is a flowchart showing an example of the operation of the ophthalmologic apparatus according to the embodiment. [Figure 24] 3A and 3B are schematic diagrams for explaining the operation of the ophthalmologic apparatus according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] An example of an embodiment of an ophthalmic device according to the present invention will be described in detail with reference to the drawings. Note that the contents of documents cited in this specification and any publicly known techniques can be incorporated into the following embodiments.

[0013] An ophthalmologic apparatus according to an embodiment includes two or more curved mirrors, an illumination optical system that irradiates a fundus of a subject's eye (examined eye) with slit-shaped illumination light via the two or more curved mirrors, and an imaging optical system that receives return light of the illumination light from the examinee's eye with an image sensor. The illumination optical system includes a slit having an opening formed therein and configured to be positioned at a fundus conjugate position that is approximately optically conjugate with the fundus of the examinee's eye, and generates slit-shaped illumination light by irradiating the slit with light from a light source. The imaging optical system includes an image sensor that is configured to be positioned at the fundus conjugate position and receives return light from the examinee's eye. The opening formed in the slit is configured so that its width in the short side direction varies depending on its position in the long side direction.

[0014] Here, the "longitudinal direction" of the opening formed in the slit means the direction in which the long side of the rectangle circumscribing the opening formed in the slit extends (longitudinal direction). The "transverse direction" of the opening formed in the slit means the direction in which the short side of the rectangle circumscribing the opening formed in the slit extends (transverse direction).

[0015] In some embodiments, the opening is formed so that its width in the short side direction at a first end, one of both longitudinal ends, is greater than its width in the short side direction at a second end, the other of both longitudinal ends. In some embodiments, the opening is formed so that its width in the short side direction at a first position in the longitudinal direction is equal to or less than its width in the short side direction at a second position closer to the first end than the first position. In some embodiments, the opening is formed so that its width in the short side direction at the second end is minimum.

[0016] This makes it possible to eliminate uneven illumination in the peripheral area of ​​the imaging area and obtain wide-angle, high-quality images of the subject's eye, even when using an optical system that requires higher resolution.

[0017] In some embodiments, the first end of the opening is displaced in the short direction relative to the long direction passing through the center of the opening, and in some embodiments, the opening includes a portion that curves from the center of the opening toward the first end.

[0018] In this case, it is possible to cancel distortion in an optical system using two or more curved mirrors, thereby eliminating distortion of the received image on the light receiving surface of the image sensor, and suppressing a decrease in contrast caused by receiving unnecessary light.

[0019] Hereinafter, the ophthalmic apparatus according to the embodiment is assumed to be configured such that an illumination optical system irradiates a slit-shaped light onto the subject's eye at a wide angle via an objective optical system provided facing the subject's eye, and a light-receiving optical system receives the light returning from the subject's eye via the objective optical system. When photographing the subject's eye, the illumination optical system is an illumination optical system that irradiates the subject's eye with illumination light, and the light-receiving optical system is an imaging optical system that receives the light returning from the subject's eye. By photographing the subject's eye at a wide angle, it is possible to obtain a wide-angle image of the subject's eye. By measuring the subject's eye at a wide angle, it is possible to obtain measurement values ​​of the optical characteristics over a wide range of the subject's eye.

[0020] Moreover, the ophthalmologic apparatus according to the embodiment includes a movement mechanism that moves the apparatus optical system relatively to the eye to be examined, and is configured to be able to align the eye to the apparatus optical system.

[0021] Specifically, the objective optical system is configured to optically relay a measurement position where the subject's eye can be positioned. In some embodiments, the objective optical system includes a reflective optical system including a reflective member (e.g., a curved mirror) arranged facing the subject's eye. In some embodiments, the objective optical system includes a refractive optical system including a refractive member (e.g., an objective lens) arranged facing the subject's eye. The ophthalmic apparatus includes an imaging unit having two or more cameras arranged so that a measurement conjugate position, which is a position approximately optically conjugate with the measurement position optically relayed by the objective optical system, is included in its field of view. That is, each of the two or more cameras is arranged so as to optically view the measurement conjugate position. In this case, the ophthalmic apparatus may include a first optical path separating member and a second optical path separating member. The first optical path separating member is arranged at the measurement conjugate position and configured to separate the optical path of light from the irradiation optical system (illumination optical system) and the optical path of light returned from the subject's eye. The second optical path separating member is arranged between the objective optical system and the first optical path separating member and configured to guide at least a portion of light from the subject's eye to the imaging unit.

[0022] Furthermore, the ophthalmic apparatus identifies the three-dimensional position of the subject's eye based on two or more captured images of the subject's eye acquired by two or more cameras. For example, the two or more cameras are arranged so that the angle between the measurement conjugate plane (a plane perpendicular to the optical system of the imaging unit) at a position optically substantially optically conjugate with the measurement position and the imaging optical axis is the same, and so that the cameras are symmetrical with respect to the normal direction of the measurement conjugate plane. In some embodiments, each of the two or more cameras is arranged on two or more imaging optical axes intersecting with the imaging reference optical axis passing through the measurement conjugate position relayed by the optical system. Here, the pupil (pupil region) of the subject's eye can be located at the measurement position. In this case, the ophthalmic apparatus can identify the three-dimensional position of the pupil of the subject's eye as the three-dimensional position of the subject's eye based on two or more anterior segment images of the subject's eye acquired using the two or more cameras.

[0023] In some embodiments, the ophthalmologic apparatus is configured to allow an examiner or a subject to manually move the device optical system relative to the subject's eye using a movement mechanism based on the identified three-dimensional position of the subject's eye (pupil). The movement mechanism moves the device optical system relative to the subject's eye by three-dimensionally moving the device optical system (objective optical system, illumination optical system, imaging optical system, and imaging unit).

[0024] In some embodiments, the ophthalmic device is configured to enable alignment of the device optical system with the test eye by having the control unit control the moving mechanism to move the device optical system with respect to the test eye based on the identified three-dimensional position of the test eye (pupil).

[0025] This makes it possible to acquire two or more images of the subject's eye and suitably align the device optical system and the subject's eye based on the acquired two or more images, even when the distance between the subject's eye and the objective optical system is short. As a result, it becomes possible to perform high-resolution wide-angle imaging or high-precision measurement of the subject's eye.

[0026] Hereinafter, an ophthalmic apparatus according to an embodiment is considered to be a fundus imaging apparatus that includes an objective optical system having two or more curved mirrors, illuminates the fundus of a subject's eye using a slit scan method, and captures a wide-angle image of the fundus by receiving return light from the illumination light from the fundus. That is, the ophthalmic apparatus is configured to scan the fundus of a subject's eye with slit-shaped illumination light via two or more curved mirrors, and receive the return light from the fundus via two or more curved mirrors with an image sensor. In this case, the ophthalmic apparatus includes a slit having an opening configured to be positioned at a fundus conjugate position, which is a position approximately optically conjugate with the fundus, and generates slit-shaped illumination light by irradiating the slit with light from a light source. The image sensor is also configured to be positioned at the fundus conjugate position.

[0027] The embodiments are not limited to ophthalmic devices (fundus imaging devices) that photograph the fundus, but can be applied to ophthalmic devices (fundus observation devices) that observe the fundus. The following embodiments can also be applied to ophthalmic devices that photograph or observe a site other than the fundus of the subject's eye. Furthermore, the following embodiments can also be applied to ophthalmic devices that measure the fundus of the subject's eye or a site other than the fundus.

[0028] In some embodiments, the two or more curved mirrors each have one or more focal points, and the two or more curved mirrors are arranged so that they share at least one focal point, for example, the two or more curved mirrors are arranged so that their two or more focal points are located on approximately the same plane (a common plane of focal points).

[0029] For example, the ophthalmologic apparatus illuminates the fundus with illumination light so that the longitudinal direction of a slit image projected onto the fundus and formed by the illumination light is substantially parallel to a plane including two or more focal points, and scans the fundus with the illumination light in a direction intersecting the longitudinal direction. Specifically, the ophthalmologic apparatus scans the fundus with the illumination light in a direction perpendicular to the longitudinal direction of the slit image. Here, the slit image is an image of an opening formed in the slit.

[0030] Examples of curved mirrors include ellipsoidal mirrors, parabolic mirrors, hyperbolic mirrors, free-form mirrors, and mirrors whose reflective surfaces are expressed by high-order polynomials. The reflective surface of a curved mirror may be a concave reflective surface or a convex reflective surface. In this case, examples of curved mirrors include ellipsoidal concave mirrors, ellipsoidal convex mirrors, parabolic concave mirrors, parabolic convex mirrors, hyperbolic concave mirrors, hyperbolic convex mirrors, free-form mirrors with concave reflective surfaces, free-form surfaces with convex reflective surfaces, concave mirrors whose reflective surfaces are expressed by high-order polynomials, and convex mirrors whose reflective surfaces are expressed by high-order polynomials.

[0031] In this specification, the focal point may not only refer to a fixed point uniquely determined by the shape of a curved surface, but may also refer to a position where the light beam (light flux) reflected by the reflecting surface is more concentrated than at other positions. Also, the position of the pupil and the position of the iris of the subject's eye may be described as being substantially the same position.

[0032] The shared focal plane is preferably a plane on which all focal points of the two or more curved mirrors are located, but may also be a plane on which two or more focal points except for at least one of all focal points of the two or more curved mirrors are located.

[0033] The control method for an ophthalmic apparatus according to the embodiment includes one or more steps for implementing processing executed by a processor (computer) in the ophthalmic apparatus according to the embodiment. The program according to the embodiment causes the processor to execute each step of the control method for an ophthalmic apparatus according to the embodiment. That is, the program according to the embodiment is a computer program including instructions that, when executed by the computer, cause the computer to execute the control method for an ophthalmic apparatus according to the embodiment. The recording medium (storage medium) according to the embodiment is any non-transitory computer-readable recording medium on which the program according to the embodiment is recorded (stored). The recording medium may be an electronic medium using magnetic, optical, magneto-optical, or semiconductor materials. Typical recording media include magnetic tape, magnetic disks, optical disks, magneto-optical disks, flash memory, and solid-state drives. Examples of magnetic disks include magnetic storage media such as hard disks, floppy disks, and ZIPs. Examples of magneto-optical disks include CD-ROMs, DVD-RAMs, DVD-ROMs, and MOs. The program can also be transmitted and received via a network such as the Internet or a LAN.

[0034] In this specification, the term "processor" refers to a circuit such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), or a programmable logic device (e.g., an SPLD (Simple Programmable Logic Device), a CPLD (Complex Programmable Logic Device), or an FPGA (Field Programmable Gate Array)). The processor realizes the functions according to the embodiment by, for example, reading and executing a program stored in a memory circuit or a storage device.

[0035] Hereinafter, the ophthalmic apparatus according to the embodiment will be described mainly in the case where the two curved mirrors are two elliptical concave mirrors. However, the following embodiment can be applied to an ophthalmic apparatus having three or more curved mirrors.

[0036] For ease of explanation, the depth direction (front-back direction) of the device will be referred to as the Z direction, the horizontal direction (left-right direction) perpendicular to the Z direction will be referred to as the X direction, and the vertical direction (up-down direction) perpendicular to the Z direction will be referred to as the Y direction. In some embodiments, the Z direction is the direction of the optical axis of the illumination light incident on the subject's eye. Here, the direction of the Z direction approaching the subject's eye may be referred to as the +Z direction, and the direction away from the subject's eye may be referred to as the -Z direction. Furthermore, the direction of the X direction from the subject's left eye to the right eye may be referred to as the +X direction, and the direction from the right eye to the left eye may be referred to as the -X direction. Furthermore, the direction of the Y direction from the subject's eye to the forehead (upward) may be referred to as the +Y direction, and the direction from the subject's forehead to the eye (downward) may be referred to as the -Y direction.

[0037] <Optical system> In the ophthalmologic apparatus according to the embodiment, the two elliptical concave mirrors are arranged so that the long axis directions of both mirrors are substantially parallel to the arrangement direction of the left eye (left subject eye) and right eye (right subject eye) of the subject to be photographed during photography. This makes it possible to photograph the subject's eye at a wide angle while keeping the subject's eye and the elliptical concave mirror close to each other without interfering with the subject's face. This ophthalmologic apparatus is configured to photograph the fundus of the subject's left eye and right eye sequentially.

[0038] In this embodiment, when illumination light deflected over a wide deflection angle range centered on the deflection reference angle direction is incident on the subject's eye via two elliptical concave mirrors (curved mirrors), the deflection reference angle direction is made different when photographing the left eye and the right eye. Therefore, when switching the subject from the left eye to the right eye or from the right eye to the left eye, it is desirable to change the orientation of the elliptical concave mirror facing the subject's eye. This makes it possible to minimize the range of movement of the optical system associated with changing the orientation of the elliptical concave mirror.

[0039] Therefore, the ophthalmologic apparatus according to the embodiment includes two elliptical concave mirrors as objective optical systems that are rotatable about a predetermined rotation axis, and includes an imaging optical system for the left eye and an imaging optical system for the right eye. Here, the illumination optical system may be common to both the left and right eyes, or may include an illumination optical system for the left eye and an illumination optical system for the right eye. Furthermore, the ophthalmologic apparatus includes a left-eye alignment optical system for aligning the device optical system with the left eye when photographing the left eye, and a right-eye alignment optical system for aligning the device optical system with the right eye when photographing the right eye.

[0040] That is, the ophthalmic apparatus includes a single objective optical system shared by both the left and right eyes, an illumination optical system, and a photographing optical system, and the photographing optical system includes at least a photographing optical system for the left eye and a photographing optical system for the right eye. The ophthalmic apparatus further includes an alignment optical system for the left eye and a alignment optical system for the right eye.

[0041] The ophthalmologic apparatus according to the embodiment will be specifically described below.

[0042] 1 to 18 are schematic diagrams showing examples of the configuration of an optical system of an ophthalmic apparatus according to an embodiment. FIG. 1 is a block diagram of an example of the configuration of an optical system of an ophthalmic apparatus according to an embodiment. FIGS. 2 to 18 show examples of the configuration of the optical system 10 of FIG. 1. In FIGS. 2 to 18, parts that are the same as those in FIG. 1 are given the same reference numerals, and descriptions thereof will be omitted where appropriate.

[0043] The ophthalmologic apparatus 1 according to the embodiment includes an optical system 10 and a moving mechanism 10D. The optical system 10 scans the fundus of the subject's left eye EL or right eye ER with slit-shaped illumination light and sequentially receives return light from the fundus. The moving mechanism 10D moves the optical system 10 relative to the left eye EL or right eye ER. The moving mechanism 10D moves the optical system 10 three-dimensionally, thereby moving the optical system 10 relative to the left eye EL or right eye ER.

[0044] The ophthalmic apparatus 1 can switch the photographing operation depending on the operation mode. In the left eye photographing mode, the ophthalmic apparatus 1 aligns the optical system 10 with respect to the left eye EL by moving the optical system 10 relative to the left eye EL using the movement mechanism 10D. Thereafter, the ophthalmic apparatus 1 scans the fundus of the left eye EL with slit-shaped illumination light using the optical system 10, and sequentially receives the return light from the fundus. In the right eye photographing mode, the ophthalmic apparatus 1 aligns the optical system 10 with respect to the right eye ER by moving the optical system 10 relative to the right eye ER using the movement mechanism 10D. Thereafter, the ophthalmic apparatus 1 scans the fundus of the right eye ER with slit-shaped illumination light using the optical system 10, and sequentially receives the return light from the fundus.

[0045] The optical system 10 includes an objective optical system 20, an illumination optical system 30, imaging optical systems 40L and 40R, optical path separating members 50L and 50R, fixation projection systems 60L and 60R, an optical path switching member 70, and anterior ocular imaging systems 80L and 80R as alignment optical systems. The anterior ocular imaging system 80L as an alignment optical system for the left eye includes two anterior ocular cameras 81LL and 81LR. The anterior ocular imaging system 80R as an alignment optical system for the right eye includes two anterior ocular cameras 81RL and 81RR. The optical system 10 also includes dichroic mirrors 90L and 90R and beam splitters BSL and BSR.

[0046] The objective optical system 20 includes a reflective optical system configured to optically relay a measurement position where the pupil of the subject's eye can be positioned. In the left eye imaging mode, the objective optical system 20 relays the left eye measurement position where the pupil (iris) of the left eye EL can be positioned to a left eye measurement conjugate position that is optically conjugate with the measurement position. In the right eye imaging mode, the objective optical system 20 relays the right eye measurement position where the pupil (iris) of the right eye ER can be positioned to a right eye measurement conjugate position that is optically conjugate with the measurement position.

[0047] The illumination optical system 30 is configured to sequentially irradiate the left eye EL and the right eye ER with slit-shaped illumination light via the objective optical system 20. Specifically, the illumination optical system 30 is configured to sequentially illuminate predetermined illumination areas on the fundus of the left eye EL while deflecting the slit-shaped illumination light in the left eye photographing mode. Also, the illumination optical system 30 is configured to sequentially illuminate predetermined illumination areas on the fundus of the right eye ER while deflecting the slit-shaped illumination light in the right eye photographing mode.

[0048] The photographing optical system 40L is configured to sequentially receive return light of the illumination light from a predetermined irradiation area on the fundus of the left eye EL in the left-eye photographing mode, and the photographing optical system 40R is configured to sequentially receive return light of the illumination light from a predetermined irradiation area on the fundus of the right eye ER in the right-eye photographing mode.

[0049] The optical path separating member 50L is disposed at the left eye measurement conjugate position and separates the optical path of the illumination light from the illumination optical system 30 from the optical path of the return light of the illumination light from the fundus of the left eye EL. The optical path separating member 50R is disposed at the right eye measurement conjugate position and separates the optical path of the illumination light from the illumination optical system 30 from the optical path of the return light of the illumination light from the fundus of the right eye ER.

[0050] The fixation projection system 60L is configured to project a fixation light beam onto the fundus of the left eye EL in the left eye photographing mode, and the fixation projection system 60R is configured to project a fixation light beam onto the fundus of the right eye ER in the right eye photographing mode.

[0051] The optical path switching member 70 is configured to guide slit-shaped illumination light generated by the illumination optical system 30 and deflected by a deflection member (optical scanner) (not shown) to the optical path separating member 50L or the optical path separating member 50R. In the left eye photography mode, the optical path switching member 70 guides the slit-shaped illumination light from the illumination optical system 30 to the optical path separating member 50L. In the right eye photography mode, the optical path switching member 70 guides the slit-shaped illumination light from the illumination optical system 30 to the optical path separating member 50R.

[0052] The two anterior eye cameras 81LL and 81LR in the anterior eye imaging system 80L are positioned to view the left eye measurement conjugate position and, in the left eye imaging mode, capture images of the anterior eye of the left eye EL from positions away from the optical axis substantially simultaneously. The two anterior eye cameras 81RL and 81RR in the anterior eye imaging system 80R are positioned to view the right eye measurement conjugate position and, in the right eye imaging mode, capture images of the anterior eye of the right eye ER from positions away from the optical axis substantially simultaneously.

[0053] The dichroic mirror 90L is disposed between the objective optical system 20 and the optical path separating member 50L, and guides at least a portion of the light from the left eye EL to the anterior-segment imaging system 80L. The light from the left eye EL may be return light of illumination light from the left eye EL, or return light of illumination light from the left eye EL illuminated by an anterior-segment illumination light source (not shown). The dichroic mirror 90R is disposed between the objective optical system 20 and the optical path separating member 50R, and guides at least a portion of the light from the right eye ER to the anterior-segment imaging system 80R. The light from the right eye ER may be return light of illumination light from the right eye ER, or return light of illumination light from the right eye ER illuminated by an anterior-segment illumination light source (not shown).

[0054] The beam splitter BSL is disposed between the optical path separating member 50L and the photographing optical system 40L, and reflects the fixation light beam from the fixation projection system 60L toward the optical path separating member 50L. The beam splitter BSR is disposed between the optical path separating member 50R and the photographing optical system 40R, and reflects the fixation light beam from the fixation projection system 60R toward the optical path separating member 50R.

[0055] Each optical system constituting the optical system 10 of FIG. 1 will now be described in detail.

[0056] (Objective optical system 20) Fig. 2 is an explanatory diagram of the configuration of the objective optical system 20 in Fig. 1. In Fig. 2, the state of the objective optical system 20 in the left eye photography mode is schematically represented by a solid line, and the state of the objective optical system 20 in the right eye photography mode is schematically represented by a dashed line. In Fig. 2, parts that are the same as those in Fig. 1 are given the same reference numerals, and descriptions thereof will be omitted where appropriate.

[0057] The objective optical system 20 includes a first elliptical concave mirror and a second elliptical concave mirror, and is configured so that the first elliptical concave mirror and the second elliptical concave mirror can be rotated around a predetermined rotation axis Ra by a rotation mechanism (not shown). The rotation axis Ra is an axis in the Z direction that passes through the center of gravity of the total mass of the first elliptical concave mirror and the second elliptical concave mirror. This allows the rotation radius to be shortened while taking weight balance into consideration. In some embodiments, the rotation axis Ra is arranged to pass through the midpoint between the left eye measurement position and the right eye measurement position. In this case, sliding movement of the optical system 10, which will be described later, associated with the rotation can be eliminated. Note that when the left eye measurement position and the right eye measurement position are the same position, the rotation axis Ra is arranged to pass through the left eye measurement position and the right eye measurement position.

[0058] In Figure 2, for the sake of convenience, the first elliptical concave mirror and the second elliptical concave mirror are referred to as the first elliptical concave mirror 21 and the second elliptical concave mirror 22 in the left eye shooting mode, and as the first elliptical concave mirror 21' and the second elliptical concave mirror 22' in the right eye shooting mode.

[0059] The reflecting surface of the first elliptical concave mirror 21 (21') is a concave ellipsoid. The first elliptical concave mirror 21 (21') is an example of a curved mirror or a concave mirror. The first elliptical concave mirror 21 (21') has two optically conjugate focal points (a first focal point F1 and a second focal point F2, or a first focal point F1' and a second focal point F2'). The first focal point F1 is a secondary pupil conjugate point of the left eye EL (a secondary left eye measurement conjugate position), and the first focal point F1' is a secondary pupil conjugate point of the right eye ER (a secondary right eye measurement conjugate position). The second focal point F2 is a primary pupil conjugate point of the left eye EL (a primary left eye measurement conjugate position), and the second focal point F2' is a primary pupil conjugate point of the right eye ER (a primary right eye measurement conjugate position).

[0060] The reflecting surface of the second elliptical concave mirror 22 (22') is a concave ellipsoid. The second elliptical concave mirror 22 (22') is an example of a curved mirror or a concave mirror. The second elliptical concave mirror 22 (22') has two optically conjugate focal points (a first focal point F3 and a second focal point F4, or a first focal point F3' and a second focal point F4'). The first focal point F3 is the primary pupil conjugate point of the left eye EL (primary left eye measurement conjugate position), and the first focal point F3' is the primary pupil conjugate point of the right eye ER (primary right eye measurement conjugate position).

[0061] The first elliptical concave mirror 21 (21') can be positioned so that the second focal point F2 (F2') coincides with or near the first focal point F3 (F3') of the second elliptical concave mirror 22 (22'). In some embodiments, the first elliptical concave mirror 21 (21') is positioned so that the second focal point F2 (F2') coincides with or near a position optically conjugate to the first focal point F3 (F3') of the second elliptical concave mirror 22 (22') (a conjugate position of the first focal point F3 (F3')).

[0062] Fig. 3A is a schematic diagram of the objective optical system 20 in the left eye imaging mode when viewed from the front of the subject, and Fig. 3B is a schematic diagram of the objective optical system 20 in the left eye imaging mode when viewed from above the subject.

[0063] In the left-eye imaging mode, the first elliptical concave mirror and the second elliptical concave mirror are rotated about the rotation axis Ra and are in a first rotation state. At this time, the two optically conjugate focal points (first focal point F1 and second focal point F2) of the first elliptical concave mirror 21 are positioned as shown in FIG. 2. That is, the first elliptical concave mirror 21 and the second elliptical concave mirror 22 are configured to relay the left-eye measurement position (F4) to the left-eye measurement conjugate position (F1). An optical path separating member 50L is disposed at or near the first focal point F1 of the first elliptical concave mirror 21. The dichroic mirror 90L is configured to reflect at least a portion of the light from the left eye EL reflected by the first elliptical concave mirror 21 in the -Y direction and guide it to the anterior-eye imaging system 80L.

[0064] Fig. 4A is a schematic diagram of the objective optical system 20 in the right eye photographing mode when viewed from the front of the subject, and Fig. 4B is a schematic diagram of the objective optical system 20 in the right eye photographing mode when viewed from above the subject.

[0065] In the right-eye imaging mode, the first elliptical concave mirror and the second elliptical concave mirror are rotated about the rotation axis Ra and enter a second rotation state. For example, the second rotation state is a state in which the mirror is rotated 180 degrees about the rotation axis Ra from the first rotation state. At this time, the two optically conjugate focal points (first focal point F1′ and second focal point F2′) of the first elliptical concave mirror 21′ are positioned as shown in FIG. 2. That is, the first elliptical concave mirror 21′ and the second elliptical concave mirror 22′ are configured to relay the right-eye measurement position (F4′) to the right-eye measurement conjugate position (F1′). An optical path separating member 50R is disposed at or near the first focal point F1′ of the first elliptical concave mirror 21′. The dichroic mirror 90R is configured to reflect at least a portion of the light from the right eye ER reflected by the first elliptical concave mirror 21′ in the −Y direction and guide it to the anterior-eye imaging system 80R.

[0066] The ophthalmologic apparatus 1 may include an objective system moving mechanism including the above-mentioned rotation mechanism, in addition to a movement mechanism for aligning the device optical system with the subject's eye. The objective system moving mechanism includes a slide mechanism that slides and moves the optical system 10 except for the objective optical system 20 in conjunction with the rotation of the above-mentioned rotation mechanism.

[0067] FIG. 5 is an explanatory diagram of the sliding movement of the optical system 10 when switching between the left eye photographing mode and the right eye photographing mode, as viewed from above the subject.

[0068] The slide mechanism moves the optical system 10', excluding the objective optical system 20, in a direction intersecting the rotation axis Ra (see FIG. 2), in conjunction with the rotation of the first elliptical concave mirror 21 and the second elliptical concave mirror 22 by the rotation mechanism. The optical system 10' moved by the slide mechanism includes the illumination optical system 30, the photographing optical systems 40L, 40R, the optical path separating members 50L, 50R, the fixation projection systems 60L, 60R, the optical path switching member 70, the anterior segment photographing systems 80L, 80R, the dichroic mirrors 90L, 90R, and the beam splitters BSL, BSR.

[0069] The sliding mechanism according to the embodiment can move the optical system 10′ along an arc-shaped path centered on a rotation axis in a predetermined vertical direction (Y direction). Examples of vertical rotation axes include a Y-direction rotation axis passing through the midpoint between the left eye measurement position and the right eye measurement position, a Y-direction rotation axis passing through the pupil of the left eye EL placed at the left eye measurement position, and a Y-direction rotation axis passing through the pupil of the right eye ER placed at the right eye measurement position. For example, when switching from the left eye imaging mode to the right eye imaging mode, the sliding mechanism moves the optical system 10′ along an arc-shaped path centered on the Y-direction rotation axis passing through the pupil of the left eye EL placed at the left eye measurement position. For example, when switching from the right eye imaging mode to the left eye imaging mode, the sliding mechanism moves the optical system 10′ along an arc-shaped path centered on the Y-direction rotation axis passing through the pupil of the right eye ER placed at the right eye measurement position.

[0070] In some embodiments, the slide mechanism moves the optical system 10' in a linear direction intersecting the rotation axis Ra in conjunction with the rotation of the first elliptical concave mirror 21 and the second elliptical concave mirror 22 by the rotation mechanism.

[0071] Such sliding movement prevents the first elliptical concave mirror 21 and the second elliptical concave mirror 22 from coming into contact with the subject's nose when switching from left eye photography mode to right eye photography mode, or from right eye photography mode to left eye photography mode.

[0072] (Optical systems other than the objective optical system 20) Figures 6A and 6B show examples of the configuration of the optical system 10 in Figure 1. Figure 6A shows an example of the configuration of the optical system 10 in left eye photography mode. Figure 6B shows an example of the configuration of the optical system 10 in right eye photography mode. In Figures 6A and 6B, parts that are the same as those in Figure 1 or 2 are given the same reference numerals, and descriptions thereof will be omitted where appropriate.

[0073] <Illumination optical system 30> The illumination optical system 30 includes a light source unit 31, an iris diaphragm 32, a relay lens 33, a slit 34, a relay lens 35, an optical scanner 95, and a relay lens 36.

[0074] The light source unit 31 outputs light in the wavelength range of the visible or infrared region.

[0075] FIG. 7 shows an example of the configuration of the light source unit 31 of FIG. 6A or 6B.

[0076] The light source unit 31 includes a projection lens 311, visible light sources 312R, 312G, and 312B, an infrared light source 312IR, and dichroic mirrors 313, 314, and 315. The visible light source 312R generates light in the wavelength range of the red (R) component. The visible light source 312G generates light in the wavelength range of the green (G) component. The visible light source 312B generates light in the wavelength range of the blue (B) component. The infrared light source 312IR generates light in the wavelength range of the near-infrared.

[0077] Each of the visible light sources 312R, 312G, 312B and the infrared light source 312IR is configured by, for example, an LED (Light Emitting Diode) or an LD (Laser Diode).

[0078] Dichroic mirrors 313, 314, and 315 are disposed between the projection lens 311 and the infrared light source 312IR.

[0079] The dichroic mirror 313 reflects light in the wavelength range emitted by the visible light source 312R toward the projection lens 311, and transmits light in the wavelength ranges emitted by the visible light sources 312G, 312B and the infrared light source 312IR to guide it to the projection lens 311.

[0080] Dichroic mirror 314 reflects light in the wavelength range emitted by visible light source 312G toward dichroic mirror 313, and transmits light in the wavelength ranges emitted by visible light source 312B and infrared light source 312IR to guide it to dichroic mirror 313.

[0081] Dichroic mirror 315 reflects light in the wavelength range emitted by visible light source 312 B toward dichroic mirror 314 , and transmits light in the wavelength range emitted by infrared light source 312 IR to guide it to dichroic mirror 314 .

[0082] By setting the visible light sources 312R, 312G, and 312B to on and the infrared light source 312IR to off, the light source unit 31 can emit white light obtained by combining the light from the visible light sources 312R, 312G, and 312B. By setting the visible light sources 312R, 312G, and 312B to off and the infrared light source 312IR to on, the light source unit 31 can emit infrared light from the infrared light source 312IR.

[0083] In some embodiments, with infrared light source 312IR set to on or off, at least one of visible light sources 312R, 312G, and 312B set to on and at least one set to off, light source unit 31 can emit a combined light of the light from visible light sources 312R, 312G, and 312B. In this case, the amount of light emitted by the visible light source set to on among visible light sources 312R, 312G, and 312B can be changed as desired.

[0084] The iris diaphragm 32 has one or more apertures formed at a position decentered from the optical axis of the illumination optical system 30. In this embodiment, the iris diaphragm 32 has a single aperture formed therein. The iris diaphragm 32 (specifically, the aperture) can be placed at a position optically conjugate with the iris (pupil) of the subject's eye to be photographed or at an iris (pupil) conjugate position that is close to the position. In other words, the iris diaphragm 32 can be placed at a position conjugate with the iris of the left eye EL or the right eye ER. The iris diaphragm 32 functions as an illumination diaphragm. In other words, the aperture formed in the iris diaphragm 32 determines the incident position (incident shape) of the illumination light on the iris of the subject's eye to be photographed.

[0085] In some embodiments, the relative position between the light source unit 31 and the opening formed in the iris diaphragm 32 is changeable. This makes it possible to change the light intensity distribution of light passing through the opening formed in the iris diaphragm 32.

[0086] The slit 34 has one or more openings formed therein. In this embodiment, the slit 34 has a single opening formed therein. The opening formed in the slit 34 is formed so that its longitudinal direction coincides with the long axis direction of the first elliptical concave mirror 21 (the direction of the line connecting the first focal point F1 and the second focal point F2). The slit 34 (specifically, the opening) can be placed at a fundus conjugate position that is optically conjugate with the fundus of the subject's eye to be photographed or in the vicinity thereof. In other words, the slit 34 can be placed at a fundus conjugate position of the left eye EL or the right eye ER. The opening formed in the slit 34 determines the shape of the illumination area (irradiation pattern shape) on the fundus of the subject's eye to be photographed.

[0087] Here, the slit 34 according to the embodiment will be described in comparison with the slit 34' according to a comparative example of the embodiment.

[0088] 8A, 8B, 9A, and 9B schematically show the relationship between the shape of an opening 34'a of a slit 34' according to a comparative example of the embodiment and the slit image (image of the opening) on ​​the light receiving surface of the image sensor.

[0089] Fig. 8A shows an outline of the configuration of a slit 34' according to a comparative example of the embodiment. Fig. 8A shows an example of the configuration of the slit 34' as viewed from the optical axis O of the illumination optical system 30. Fig. 8B schematically shows a slit image SLI0 on the light receiving surface SR of the image sensor according to the comparative example of the embodiment.

[0090] FIG. 9A schematically shows a slit image on the light-receiving surface SR of the image sensor when the fundus of the subject's eye is scanned with slit-shaped illumination light according to a slit scanning method described below in a comparative example of the embodiment. As described below, the fundus is scanned with the illumination light by deflecting the illumination light using an optical scanner 95 described below. FIG. 9A also shows a slit image SLI0 on the light-receiving surface SR of the image sensor when the deflection angle of the illumination light is "0 degrees," and a slit image SLI1 on the light-receiving surface SR of the image sensor when the deflection angle of the illumination light is "α (α > 0 or α < 0) degrees." The deflection angle "0 degrees" is the deflection reference angle. FIG. 9B shows an example of a fundus image acquired using a slit 34' according to a comparative example of the embodiment.

[0091] 2 to 6B, when slit-shaped illumination light is incident on the subject's eye via a curved mirror such as an elliptical concave mirror, distortion of the optical system can be canceled by curving the shape of the opening 34'a of the slit 34' along the longitudinal direction. This distortion of the optical system includes optical distortion of the objective optical system and distortion caused by the degree of eccentricity (eccentricity of the light division position from the optical axis) of pupil division of light entering and exiting the objective optical system by optical path separating members 50L and 50R, which will be described later.

[0092] That is, as shown in FIG. 8A, the opening 34'a formed in the slit 34' is curved along the longitudinal direction SD. Here, the longitudinal direction SD is the long axis direction of the first elliptical concave mirror 21 (a direction optically approximately parallel to the long axis direction). This makes it possible to receive the slit image SLI0 on the light receiving surface SR of the image sensor 47L (47R) within the exposure width EW of a rectangular area, as shown in FIG. 8B. As a result, the slit image can be received efficiently without widening the exposure width EW, and a uniform fundus image can be obtained while eliminating unnecessary flare, ghosts, and the like.

[0093] However, as shown in FIG. 9A, the deviation of the deflection angle of the illumination light from the reference deflection angle may result in distortion due to, for example, the degree of eccentricity of the pupil division, making it impossible to receive the slit image SLI1 within the exposure width EW on the light-receiving surface SR of the image sensor 47L (47R). In this case, in an optical system requiring higher resolution, simply curving the shape of the opening 34'a formed in the slit 34' will not allow the slit image to be received within the exposure width EW, and the tilt of the slit image at the field angle at the edge of the scan area will result in illumination unevenness. As a result, as shown in FIG. 9B, artifacts due to illumination unevenness (e.g., the shadow area in the upper left) appear in the acquired fundus image IMG0.

[0094] 10 shows an example of an optical simulation result of a received light image on the light receiving surface of the image sensor 47L (47R) in a comparative example of the embodiment. In FIG. 10, the horizontal axis indicates the horizontal direction of the light receiving surface, and the vertical axis indicates the vertical direction of the light receiving surface.

[0095] 10 shows the optical simulation results of the slit image SLI1 on the light receiving surface SR of the image sensor 47L (47R) when the deflection angle is "α degrees" as shown in FIG. 9A. As shown in FIG. 10, when the deflection angle is "α degrees," the slit image SLI1 does not fit within the exposure width EW on the light receiving surface SR. As a result, uneven illumination occurs as shown in FIG. 8B, degrading the image quality of the fundus image IMG0.

[0096] In contrast, the slit 34 according to the embodiment has an opening formed so that the width in the short direction varies depending on the position in the long direction. This makes it possible to eliminate uneven illumination at the field of view at the edges of the scan area. The opening of the slit 34 may be curved along the long direction.

[0097] 11, 12A, and 12B schematically show the shape of the opening of the slit 34 according to the embodiment and the opening of the slit image on the light receiving surface of the image sensor.

[0098] In the slit 34 according to the embodiment, the opening 34a is formed so that the width in the short-side direction BW varies depending on the position in the longitudinal direction SD. That is, in the slit 34 according to the embodiment, the opening 34a is formed so that the width ΔM1 in the short-side direction BW of a first end UP, which is one of both end portions in the longitudinal direction SD, differs from the width ΔM2 in the short-side direction BW of a second end DW, which is the other of both end portions. In some embodiments, the opening 34a is further formed so as to curve along the longitudinal direction SD.

[0099] In some embodiments, the opening 34a is formed so that a width ΔM1 in the short-side direction BW at a first end UP in the longitudinal direction SD is larger than a width ΔM2 in the short-side direction BW at a second end DW (ΔM1>ΔM2). Here, the first end UP is the end on the first focal point F1 side on the major axis of the first elliptical concave mirror 21, and the second end DW is the end on the second focal point F2 side on the major axis of the first elliptical concave mirror 21. The longitudinal direction SD corresponds to the direction of a straight line connecting the first focal point F1 and the second focal point F2 of the first elliptical concave mirror 21 (the major axis direction).

[0100] In some embodiments, the opening 34a is formed so that the width in the short side direction BW at a first position in the longitudinal direction SD is equal to or less than the width in the short side direction BW at a second position closer to the first end UP than the first position. In some embodiments, the opening 34a is formed so that the width in the short side direction BW at the second end DW is minimum.

[0101] In some embodiments, the first end UP of the opening 34a is displaced in the short-side direction BW with respect to the longitudinal direction SD passing through the opening center (a position passing through the optical axis O). For example, in the opening 34a, the first end UP is displaced in the short-side direction BW in response to a displacement from the optical axis of an opening formed in the photographic diaphragm 52L (52R) described below at the left eye measurement conjugate position (or the right eye measurement conjugate position). In some embodiments, the opening 34a includes a portion that changes in a curved shape from the opening center toward the first end UP.

[0102] Fig. 12A shows a schematic diagram of a slit image on the light receiving surface SR of the image sensor when the fundus of the subject's eye is scanned with a slit-shaped illumination light according to the slit scanning method in this embodiment. Fig. 12A shows a schematic diagram of a slit image SLI10 on the light receiving surface SR of the image sensor when the deflection angle of the illumination light is "0 degrees" and a slit image SLI11 on the light receiving surface SR of the image sensor when the deflection angle of the illumination light is "α degrees." Fig. 12B shows an example of a fundus image acquired using the slit 34 according to this embodiment.

[0103] 12A, when the deflection angle of the illumination light is "0 degrees," the slit image SLI10 on the light-receiving surface SR of the image sensor 47L (47R) can be received within the exposure width EW of the rectangular area. Furthermore, even when the deflection angle of the illumination light is "α degrees" away from the deflection reference angle, the slit image SLI11 can be received within the exposure width EW on the light-receiving surface SR of the image sensor 47L (47R).

[0104] As a result, even in optical systems that require higher resolution, the slit image can be received efficiently without widening the exposure width EW, and a uniform fundus image can be obtained while eliminating unnecessary flare, ghosts, etc.

[0105] For example, as shown in FIG. 12B, the occurrence of artifacts due to uneven illumination is suppressed in the acquired fundus image IMG10.

[0106] As described above, the illumination light emitted from the light source unit 31 passes through the slit 34 and is projected onto the reflecting surface of the first elliptical concave mirror 21 so that the longitudinal direction of the slit-shaped illumination light substantially coincides with the long axis direction of the first elliptical concave mirror 21. The illumination light projected onto the reflecting surface of the first elliptical concave mirror 21 is guided as slit-shaped illumination light to the fundus of the subject's eye to be photographed.

[0107] The slit 34 can be moved in the optical axis direction of the illumination optical system 30 by a moving mechanism (specifically, a moving mechanism 34D described later), not shown, so that the position of the slit 34 can be moved according to the state of the subject's eye to be photographed (specifically, the diopter (refractive power) or the shape of the fundus (fundus curvature)).

[0108] For example, first control information in which the position of the slit 34 on the optical axis of the illumination optical system 30 is previously associated with each of a plurality of diopters is stored in a storage unit 102 described below. The main control unit 101 refers to the first control information to identify the position of the slit 34 corresponding to the diopter, and controls the movement mechanism 34D so that the slit 34 is positioned at the identified position.

[0109] Here, the light intensity distribution of the light passing through the opening formed in the slit 34 changes as the slit 34 moves. At this time, the main control unit 101 can change the position and orientation of the light source included in the light source unit 31 by controlling a movement mechanism (not shown) that moves the light source unit 31.

[0110] In some embodiments, the slit 34 is configured to be able to change at least one of the position and shape of the opening depending on the state of the subject's eye to be photographed without being moved in the optical axis direction. Such a function of the slit 34 is realized by, for example, a liquid crystal shutter.

[0111] The slit 34 of the embodiment is configured to be able to be positioned on the optical axis of the illumination optical system 30 with different intersection angles (tilt angles) with respect to the optical axis of the illumination optical system 30 depending on the subject's eye to be photographed (see Figures 6A and 6B).

[0112] Specifically, the slit 34 is inclined and disposed on the optical axis of the illumination optical system 30 at an intersection angle corresponding to the major axis direction (the direction of the line connecting the two focal points) of the first elliptical concave mirror 21, onto which the slit-shaped illumination light is incident. For example, in the left-eye photography mode, the slit 34 is disposed on the optical axis of the illumination optical system 30 so that the exit surface of the slit 34 is optically approximately parallel to the major axis direction of the first elliptical concave mirror 21 (the direction of the line connecting the first focal point F1 and the second focal point F2) shown in FIG. 6A. Also, for example, in the right-eye photography mode, the slit 34 is disposed on the optical axis of the illumination optical system 30 so that the exit surface of the slit 34 is optically approximately parallel to the major axis direction of the first elliptical concave mirror 21 (the direction of the line connecting the first focal point F1′ and the second focal point F2′) shown in FIG. 6B. Here, "optically approximately parallel" means not only a state in which the light is approximately parallel on an optical axis (optical path) that extends in a straight line in real space, but also a state that is substantially equivalent to a state in which the light is approximately parallel on a virtual optical axis obtained by removing the reflecting member or the like from the optical axis deflected by the reflecting member or the like.

[0113] The optical scanner 95 deflects the slit-shaped illumination light generated by irradiating the slit 34 with illumination light from the light source unit 31. The optical scanner 95 (specifically, the deflection surface) can be positioned at a position optically conjugate with the iris (pupil) of the subject's eye to be photographed or at an iris-conjugate position nearby. The optical scanner 95 is a uniaxial optical scanner that changes the orientation of the deflection surface around a predetermined deflection reference angle direction. The optical scanner 95 one-dimensionally deflects the slit-shaped illumination light. The optical scanner 95 deflects the illumination light in a direction intersecting (specifically, perpendicular to) the longitudinal direction of a slit image formed by the slit-shaped illumination light projected onto the fundus of the subject's eye to be photographed. This causes the slit image to move in a direction intersecting the longitudinal direction of the slit image (the scanning direction).

[0114] The optical scanner 95 includes, for example, a galvanometer scanner, a microelectromechanical system (MEMS) scanner, a polygon mirror, or a resonant scanner. For example, the optical scanner 95 includes a galvanometer scanner that deflects the illumination light within a predetermined deflection angle range based on a predetermined deflection reference angle direction.

[0115] In some embodiments, the optical scanner 95 is a biaxial optical scanner that two-dimensionally deflects a slit-shaped illumination light. For example, the optical scanner 95 includes a first scanner and a second scanner. The first scanner deflects the illumination light so as to move the illumination area on the fundus of the subject's eye to be photographed in a horizontal direction perpendicular to the optical axis of the illumination optical system 30. The second scanner deflects the illumination light deflected by the first scanner so as to move the illumination area on the fundus in a vertical direction perpendicular to the optical axis of the illumination optical system 30.

[0116] In the optical system having the configuration described above, illumination light in the visible or infrared region emitted from light source unit 31 is irradiated onto iris diaphragm 32, passes through an opening formed in iris diaphragm 32, transmits through relay lens 33, and is guided to slit 34.

[0117] In the left-eye photography mode, the slit 34 is positioned so that the exit surface of the slit 34 is optically approximately parallel to the major axis direction of the first elliptical concave mirror 21 (the direction of the line connecting the first focal point F1 and the second focal point F2), as shown in Fig. 6A. In the right-eye photography mode, the slit 34 is positioned so that the exit surface of the slit 34 is optically approximately parallel to the major axis direction of the first elliptical concave mirror 21 (the direction of the line connecting the first focal point F1' and the second focal point F2'), as shown in Fig. 6B. The slit-shaped illumination light that passes through the opening formed in the slit 34 passes through the relay lens 35, is deflected by the optical scanner 95, passes through the relay lens 36, and is guided to the optical path switching member 70.

[0118] In some embodiments, the illumination optical system 30 includes a projector equipped with a light source, and the projector outputs slit-shaped illumination light. In this case, the projector is provided instead of the light source unit 31, iris diaphragm 32, relay lens 33, and slit 34 shown in Figures 6A and 6B. Projectors include LCD (Liquid Crystal Display) projectors using a transmissive liquid crystal panel, LCOS (Liquid Crystal On Silicon) projectors using a reflective liquid crystal panel, and DLP (Digital Light Processing) (registered trademark) projectors using a DMD (Digital Mirror Device).

[0119] The optical path switching member 70 switches the optical path of the slit-shaped illumination light deflected by the optical scanner 95, depending on the subject's eye to be photographed. Specifically, the optical path switching member 70 guides the slit-shaped illumination light to the left eye measurement conjugate position (first focal point F1 in FIG. 6A) or the right eye measurement conjugate position (first focal point F1' in FIG. 6B), depending on the photographing mode.

[0120] A relay lens 37L, a reflecting member 38L, and a relay lens 39L are disposed between the optical path switching member 70 and the left eye measurement conjugate position where the optical path separating member 50L is disposed. A relay lens 37R, a reflecting member 38R, and a relay lens 39R are disposed between the optical path switching member 70 and the right eye measurement conjugate position where the optical path separating member 50R is disposed.

[0121] In the left eye photography mode, the optical path switching member 70 guides the slit-shaped illumination light that has passed through the relay lens 36 to the relay lens 37L. In the right eye photography mode, the optical path switching member 70 guides the slit-shaped illumination light that has passed through the relay lens 36 to the relay lens 37R. The function of the optical path switching member 70 can be realized by a known optical path switching member such as a flip mirror.

[0122] In some embodiments, the illumination optical system 30 further includes a light path switching member 70, relay lenses 37L and 37R, reflecting members 38L and 38R, and relay lenses 39L and 39R.

[0123] By adjusting the orientation of the optical axis of the illumination optical system 30 using the optical path switching member 70 and the reflecting members 38L and 38R, it is possible to reduce the size of the optical system 10 in the X and Y directions. For example, by changing the orientation of the optical axis in the +X direction using the reflecting member 38L and changing the orientation of the optical axis in the -X direction using the reflecting member 38R, it is possible to reduce the size of the optical system 10 in the X direction.

[0124] <40L and 40R optical systems> The photographing optical system 40L includes a relay lens 45L, an imaging lens 46L, and an image sensor 47L. The photographing optical system 40L is configured to be movable in an integrated manner in the optical axis direction. This allows the light receiving surface of the image sensor 47L to be positioned at a fundus conjugate position that is optically conjugate with the fundus of the left eye EL or a position close to the fundus conjugate position. As a result, the photographing optical system 40L can be adapted to the state of the left eye EL and the returned light from the left eye EL can be imaged on the light receiving surface of the image sensor 47L. In some embodiments, the photographing optical system 40L includes a focusing lens, and is configured to be able to position the light receiving surface of the image sensor 47L at the fundus conjugate position by moving the focusing lens in the optical axis direction.

[0125] The return light from the left eye EL is scattered light (reflected light) of the illumination light incident on the left eye EL. In some embodiments, the return light from the left eye EL includes scattered light (reflected light) of the illumination light incident on the left eye EL, and fluorescent light excited by the illumination light incident on the left eye EL and its scattered light.

[0126] The image sensor 47L functions as a two-dimensional image sensor as a pixelated light receiver. The light receiving surface (detection surface, imaging surface) of the image sensor 47L can be placed at the fundus conjugate position. The image sensor 47L can set a virtually movable light receiving area (light receiving area) at the fundus conjugate position.

[0127] For example, the light reception results by the image sensor 47L are captured and read out using a rolling shutter system. In some embodiments, the light reception results by the image sensor 47L are captured and read out using a global shutter system that allows a light reception area to be changed or moved. In some embodiments, a control unit, which will be described later, controls the image sensor 47L to control the reading of the light reception results. In some embodiments, the image sensor 47L can automatically output the light reception results for a predetermined line together with information indicating the light reception position.

[0128] Such an image sensor 47L includes, for example, a CMOS (Complementary Metal Oxide Semiconductor) image sensor. In this case, the image sensor 47L includes a plurality of pixels (light receiving elements) arranged in a row direction, each of which is arranged in a column direction. Specifically, the image sensor 47L includes a plurality of pixels arranged two-dimensionally, a plurality of vertical signal lines, and a plurality of horizontal signal lines.

[0129] In some embodiments, image sensor 47L includes, for example, a charge coupled device (CCD) image sensor.

[0130] By capturing (reading) the result of receiving the returned light from the image sensor 47L using a rolling shutter method, an image in a light-receiving area corresponding to a desired virtual opening shape extending in the row direction is obtained. Such control is disclosed, for example, in Patent Document 2 or U.S. Patent No. 8,237,835.

[0131] A reflecting member 41L, a relay lens 42L, a reflecting member 43L, and a beam splitter BSL are disposed between the optical path separating member 50L and the photographing optical system 40L. A fixation projection system 60L (described below) is disposed in the reflection direction of the beam splitter BSL. In some embodiments, the photographing optical system 40L includes a reflecting member 41L, a relay lens 42L, a reflecting member 43L, and a beam splitter BSL.

[0132] The return light of the illumination light from the left eye EL separated by the optical path separating member 50L is reflected by the reflecting member 41L, passes through the relay lens 42L, is reflected by the reflecting member 43L, passes through the beam splitter BSL, and is guided to the photographing optical system 40L. The return light guided to the photographing optical system 40L passes through the relay lens 45L, and is imaged on the light receiving surface of the image sensor 47L by the imaging lens 46L.

[0133] On the other hand, the photographing optical system 40R has a configuration similar to that of the photographing optical system 40L. That is, the photographing optical system 40R includes a relay lens 45R, an imaging lens 46R, and an image sensor 47R. The photographing optical system 40R is configured to be movable in an integrated manner in the optical axis direction. This allows the light receiving surface of the image sensor 47R to be positioned at a position optically conjugate with the fundus of the right eye ER or at a fundus conjugate position near the position. As a result, the photographing optical system 40R can be adapted to the state of the right eye ER and can form an image of the returned light from the right eye ER on the light receiving surface of the image sensor 47R. In some embodiments, the photographing optical system 40R includes a focusing lens, and is configured to be able to position the light receiving surface of the image sensor 47R at the fundus conjugate position by moving the focusing lens in the optical axis direction.

[0134] The return light from the right eye ER is scattered light (reflected light) of the illumination light that entered the right eye ER. In some embodiments, the return light from the right eye ER includes scattered light (reflected light) of the illumination light that entered the right eye ER, and fluorescence excited by the illumination light that entered the right eye ER and its scattered light.

[0135] Like the image sensor 47L, the image sensor 47R functions as a two-dimensional image sensor as a pixelated light receiver. The light receiving surface (detection surface, imaging surface) of the image sensor 47R can be placed at the fundus conjugate position. The image sensor 47R can set a virtually movable light receiving area (light receiving area) at the fundus conjugate position.

[0136] Like image sensor 47L, the light reception results by image sensor 47R are captured and read out using a rolling shutter system. In some embodiments, the light reception results by image sensor 47R are captured and read out using a global shutter system that allows the light reception area to be changed or moved. In some embodiments, a control unit, which will be described later, controls the image sensor 47R to control the reading of the light reception results. In some embodiments, image sensor 47R can automatically output the light reception results for a predetermined line together with information indicating the light reception position.

[0137] Such image sensor 47R, like image sensor 47L, includes a CMOS image sensor. In some embodiments, image sensor 47R includes, for example, a CCD image sensor.

[0138] By capturing (reading) the result of receiving the returned light from the image sensor 47R using a rolling shutter method, an image in a light-receiving area corresponding to a desired virtual opening shape extending in the row direction is obtained.

[0139] A reflecting member 41R, a relay lens 42R, a reflecting member 43R, and a beam splitter BSR are disposed between the optical path separating member 50R and the photographing optical system 40R. A fixation projection system 60R (described below) is disposed in the reflection direction of the beam splitter BSR. In some embodiments, the photographing optical system 40R includes a reflecting member 41R, a relay lens 42R, a reflecting member 43R, and a beam splitter BSR.

[0140] The return light of the illumination light from the right eye ER, which has been separated by the optical path separating member 50R, is reflected by the reflecting member 41R, passes through the relay lens 42R, is reflected by the reflecting member 43R, passes through the beam splitter BSR, and is guided to the photographing optical system 40R. The return light guided to the photographing optical system 40R passes through the relay lens 45R, and is imaged on the light-receiving surface of the image sensor 47R by the imaging lens 46R.

[0141] By adjusting the orientation of the optical axes of the photographing optical systems 40L and 40R using the reflecting members 41L, 43L, 41R, and 43R, it is possible to reduce the size of the optical system 10 in the X and Y directions. For example, by changing the orientation of the optical axes in the +X direction using the reflecting members 41L and 43L and changing the orientation of the optical axes in the -X direction using the reflecting members 41R and 43R, it is possible to reduce the size of the photographing optical systems 40L and 40R in the X direction. For example, the reflecting members 41L and 43L can adjust the orientation of the optical axis of the photographing optical system 40L so that it substantially coincides with the Z direction. For example, the reflecting members 41R and 43R can adjust the orientation of the optical axis of the photographing optical system 40R so that it substantially coincides with the Z direction.

[0142] <Fixation projection system 60L, 60R> The fixation projection system 60L projects a fixation light beam onto the fundus of the left eye EL in the left eye photographing mode, and the fixation projection system 60R projects a fixation light beam onto the fundus of the right eye ER in the right eye photographing mode.

[0143] The fixation projection system 60L has the same configuration as the fixation projection system 60R.

[0144] FIG. 13 shows an example of the configuration of the fixation projection system 60L in FIG. 6A (the fixation projection system 60R in FIG. 6B).

[0145] The fixation projection system 60L includes a fixation light source 61L and a projection lens 62L. The fixation light source 61L can be placed at a position optically conjugate with the fundus of the left eye EL or at a fundus conjugate position near the position. The fixation light beam emitted by the fixation light source 61L passes through the projection lens 62L, is reflected by the beam splitter BSL, passes through the reflecting member 43L, the relay lens 42L, and the reflecting member 41L, and is guided to the optical path separating member 50L. The fixation light beam guided to the optical path separating member 50L passes through the dichroic mirror 90L and is projected onto the fundus of the left eye EL via the first elliptical concave mirror 21 and the second elliptical concave mirror 22 (see FIG. 6A).

[0146] The fixation projection system 60R includes a fixation light source 61R and a projection lens 62R. The fixation light source 61R can be placed at a fundus conjugate position, which is optically conjugate with the fundus of the right eye ER or in the vicinity thereof. The fixation light beam emitted by the fixation light source 61R passes through the projection lens 62R, is reflected by the beam splitter BSR, passes through the reflecting member 43R, the relay lens 42R, and the reflecting member 41R, and is directed to the optical path separating member 50R. The fixation light beam directed to the optical path separating member 50R passes through the dichroic mirror 90R and is projected onto the fundus of the right eye ER via the first elliptical concave mirror 21 and the second elliptical concave mirror 22 (see FIG. 6B).

[0147] <Optical path separating members 50L and 50R> As described above, the optical path separating member 50L is disposed at a left eye measurement conjugate position that is optically conjugate with the left eye measurement position, and the optical path separating member 50R is disposed at a right eye measurement conjugate position that is optically conjugate with the right eye measurement position.

[0148] The optical path separating member 50L has the same configuration as the optical path separating member 50R.

[0149] An example of the configuration of the optical path separating member 50L is shown in Fig. 14. Fig. 14 shows a schematic cross-sectional structure of the optical path separating member 50L.

[0150] The optical path separating member 50L includes a reflecting member 51L as a pupil division mirror, and a photographic diaphragm 52L. The photographic diaphragm 52L has an opening formed in a position decentered from the optical axis O. The reflecting member 51L is provided at a position decentered from the optical axis O on the surface of the photographic diaphragm 52L on the reflecting surface side of the first elliptical concave mirror 21. In other words, the reflecting member 51L and the photographic diaphragm 52L are each disposed at a left eye measurement conjugate position.

[0151] FIG. 15 shows a schematic representation of the conjugate plane at the left eye measurement conjugate position.

[0152] The conjugate plane PL is a virtual plane that is perpendicular to the optical axis O at a left-eye measurement conjugate position on the optical axis O. An image AP1 of the aperture formed in the iris diaphragm 32 and an image AP2 of the aperture formed in the photographing diaphragm 52L are arranged on the conjugate plane PL. At this time, the image of the aperture formed in the photographing diaphragm 52L and the image of the aperture formed in the iris diaphragm 32 are arranged so that they do not overlap.

[0153] Therefore, in the optical path separating member 50L, the reflecting member 51L reflects the slit-shaped illumination light from the illumination optical system 30 and guides it to the objective optical system 20 (first elliptical concave mirror 21). The photographic diaphragm 52L guides the returning light that has passed through its opening to the photographic optical system 40L.

[0154] Similarly, the optical path separating member 50R includes a reflecting member 51R as a pupil dividing mirror and a photographic diaphragm 52R. The photographic diaphragm 52R has an opening formed at a position decentered from the optical axis. The reflecting member 51R is provided at a position decentered from the optical axis on the surface of the photographic diaphragm 52R on the reflecting surface side of the first elliptical concave mirror 21. In other words, the reflecting member 51R and the photographic diaphragm 52R are each disposed at a right eye measurement conjugate position.

[0155] That is, on the conjugate plane at the right-eye measurement conjugate position, an image of the aperture formed in the iris diaphragm 32 and an image of the aperture formed in the photographing diaphragm 52R are arranged, similar to Fig. 15. Therefore, in the optical path separating member 50R, the reflecting member 51R reflects the slit-shaped illumination light from the illumination optical system 30 and guides it to the objective optical system 20 (first elliptical concave mirror 21). The photographing diaphragm 52R guides the returning light that has passed through its opening to the photographing optical system 40R.

[0156] <Anterior segment imaging system 80L, 80R> Figure 16 shows a schematic diagram of the positional relationship between the objective optical system 20 and the anterior eye imaging systems 80L and 80R when viewed from the reflecting surface side of the second elliptical concave mirror 22 (22'). In Figure 16, the same parts as in Figures 1, 2, 6A, and 6B are designated by the same reference numerals, and their explanations will be omitted where appropriate.

[0157] The anterior eye imaging system 80L is arranged in the -Y direction, which is the reflection direction of the dichroic mirror 90L, as shown in Fig. 16. The anterior eye imaging system 80R is arranged in the -Y direction, which is the reflection direction of the dichroic mirror 90R, as shown in Fig. 16. This makes it possible to reduce the size of the optical system 10 at least in the X direction.

[0158] An example of the configuration of the anterior eye imaging system 80L (80R) is shown in Fig. 17. In Fig. 17, the same parts as those in Fig. 1 or 16 are given the same reference numerals, and the description thereof will be omitted where appropriate.

[0159] The anterior eye imaging system 80L includes two anterior eye cameras 81LL and 81LR, as well as an optical path deflection prism 82L and imaging lenses 82LL and 82LR.

[0160] The light receiving surface (imaging surface) of each of the anterior eye cameras 81LL and 81LR can be arranged at a fundus conjugate position, which is a position that is approximately optically conjugate with the fundus of the left eye EL or a position close to the fundus conjugate position. For example, the anterior eye cameras 81LL and 81LR are arranged so that the angles formed between the left eye measurement conjugate plane perpendicular to the optical axis and the imaging optical axes Lref and Rref are the same at the left eye measurement conjugate position, and so that they are symmetrical with respect to the normal direction (optical axis direction) of the left eye measurement conjugate plane. In some embodiments, the light receiving surface (imaging surface) is arranged at the fundus conjugate position by moving the anterior eye cameras 81LL and 81LR in the optical axis direction. In some embodiments, two focusing lenses are provided between the dichroic mirror 90L and the imaging lenses 82LL and 82LR, respectively, and the light receiving surface (imaging surface) is arranged at the fundus conjugate position by moving each of the two focusing lenses in the optical axis direction.

[0161] For example, the photographing reference optical axis Ref of the anterior-segment photographing system 80L deflected by the dichroic mirror 90L is an optical axis that passes through the midpoint of the baseline of the anterior-segment cameras 81LL and 81LR and is perpendicular to the baseline. The photographing optical axis Lref of the anterior-segment camera 81LL and the photographing optical axis Rref of the anterior-segment camera 81LR are arranged so that they pass through a position optically equivalent to the left-eye measurement conjugate position. That is, the anterior-segment cameras 81LL and 81LR are arranged on photographing optical axes Lref and Rref that intersect with the photographing reference optical axis Ref, respectively.

[0162] In some embodiments, an optical path deflection prism 82L is provided as shown in FIG. 17. The optical path deflection prism 82L is, for example, a triangular prism having first and second deflection surfaces that intersect at a predetermined angle and share a common ridge. In this case, the returning light reflected by the dichroic mirror 90L is deflected by the first deflection surface of the optical path deflection prism 82L toward the imaging lens 82LL, which forms an image on the light receiving surface of the anterior eye camera 81LL. The returning light reflected by the dichroic mirror 90L is deflected by the second deflection surface of the optical path deflection prism 82L toward the imaging lens 82LR, which forms an image on the light receiving surface of the anterior eye camera 81LR.

[0163] This allows the anterior eye cameras 81LL and 81LR to be positioned so as to optically view the left eye measurement conjugate position while avoiding physical interference between the anterior eye cameras 81LL and 81LR.

[0164] Figure 18 is a schematic diagram showing the photographing optical axes of the anterior eye cameras 81LL and 81LR in the objective optical system 20. In Figure 18, the same parts as those in Figures 1, 2, 16, and 17 are designated by the same reference numerals, and descriptions thereof will be omitted where appropriate.

[0165] 18, the anterior eye cameras 81LL and 81LR are disposed so as to view a left eye measurement conjugate position (or a position optically conjugate with the left eye measurement conjugate position) that is optically equivalent to the left eye measurement position where the left eye EL is disposed. That is, the anterior eye cameras 81LL and 81LR can photograph the left eye EL from positions away from the optical axes of the illumination optical system 30 and the photographing optical system 40L.

[0166] Similarly, the anterior eye imaging system 80R includes two anterior eye cameras 81RL and 81RR, as well as an optical path deflection prism 82R and imaging lenses 82RL and 82RR (see FIG. 17).

[0167] The light receiving surface (imaging surface) of each of the anterior eye cameras 81RL and 81RR can be arranged at a fundus conjugate position, which is a position that is approximately optically conjugate with the fundus of the right eye ER or a position close to the fundus conjugate position. For example, the anterior eye cameras 81RL and 81RR are arranged so that the angle between the right eye measurement conjugate plane perpendicular to the optical axis and the imaging optical axis is the same at the right eye measurement conjugate position, and so that they are symmetrical with respect to the normal direction (optical axis direction) of the right eye measurement conjugate plane. In some embodiments, the light receiving surface (imaging surface) is arranged at the fundus conjugate position by moving the anterior eye cameras 81RL and 81RR in the optical axis direction. In some embodiments, two focusing lenses are provided between the dichroic mirror 90R and the imaging lenses 82RL and 82RR, respectively, and the light receiving surface (imaging surface) is arranged at the fundus conjugate position by moving each of the two focusing lenses in the optical axis direction.

[0168] For example, the photographing reference optical axis Ref of the anterior-segment photographing system 80R deflected by the dichroic mirror 90R passes through the midpoint of the baseline of the anterior-segment cameras 81RL and 81RR and is an optical axis perpendicular to the baseline. The photographing optical axis Lref of the anterior-segment camera 81RL and the photographing optical axis Rref of the anterior-segment camera 81RR are arranged so as to pass through a position optically equivalent to the right-eye measurement conjugate position. That is, the anterior-segment cameras 81RL and 81RR are arranged on photographing optical axes Lref and Rref that intersect with the photographing reference optical axis Ref, respectively.

[0169] In some embodiments, an optical path deflection prism 82R is provided as shown in FIG. 17. The optical path deflection prism 82R is, for example, a triangular prism having first and second deflection surfaces that intersect at a predetermined angle and share a common ridge. In this case, the returning light reflected by the dichroic mirror 90R is deflected by the first deflection surface of the optical path deflection prism 82R toward the imaging lens 82RL, which forms an image on the light receiving surface of the anterior eye camera 81RL. The returning light reflected by the dichroic mirror 90R is deflected by the second deflection surface of the optical path deflection prism 82R toward the imaging lens 82RR, which forms an image on the light receiving surface of the anterior eye camera 81RR.

[0170] This allows the anterior eye cameras 81RL and 81RR to be positioned so as to optically view the right eye measurement conjugate position while avoiding physical interference between the anterior eye cameras 81RL and 81RR.

[0171] Therefore, like the anterior eye cameras 81LL and 81LR, the anterior eye cameras 81RL and 81RR are disposed so as to view a right eye measurement conjugate position (or a position optically conjugate with the right eye measurement conjugate position) that is optically equivalent to the right eye measurement position where the right eye ER is disposed. In other words, the anterior eye cameras 81RL and 81RR can photograph the right eye ER from positions away from the optical axes of the illumination optical system 30 and the photographing optical system 40L.

[0172] In some embodiments, at least one of the first elliptical concave mirror 21 and the second elliptical concave mirror 22 is a convex mirror (e.g., an elliptical convex mirror) whose reflective surface is formed in a convex shape. In some embodiments, at least one of the first elliptical concave mirror 21 and the second elliptical concave mirror 22 is a curved mirror whose reflective surface is a free-form surface.

[0173] The ophthalmologic apparatus 1 may also be provided with any element or unit, such as a member for supporting the face of the subject (a chin rest, a forehead rest, etc.).

[0174] The first elliptical concave mirror 21 and the second elliptical concave mirror 22 are an example of "two curved mirrors" according to the embodiment. The anterior eye imaging system 80L or the anterior eye imaging system 80R is an example of an "imaging unit" according to the embodiment. The optical path separating member 50L or the optical path separating member 50R is an example of a "first optical path separating member" according to the embodiment. The dichroic mirror 90L or the dichroic mirror 90R is an example of a "second optical path separating member" according to the embodiment. The iris diaphragm 32 is an example of an "illumination diaphragm" according to the embodiment. The anterior eye imaging system 80L is an example of a "left eye imaging unit" according to the embodiment. The anterior eye imaging system 80R is an example of a "right eye imaging unit" according to the embodiment. The imaging optical system 40L is an example of a "left eye imaging optical system" according to the embodiment. The imaging optical system 40R is an example of a "right eye imaging optical system" according to the embodiment. The optical path separating member 50L is an example of a "left eye optical path separating member" according to the embodiment. The optical path separating member 50R is an example of the "optical path separating member for the right eye" according to the embodiment.

[0175] <Control system> Fig. 19 shows an example of the configuration of a control system of the ophthalmologic apparatus 1 according to the embodiment. In Fig. 19, the same parts as those in Figs. 1 to 18 are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0176] The control system (processing system) of the ophthalmic apparatus 1 is mainly configured with a control unit 100. The control unit 100 controls each unit of the ophthalmic apparatus 1.

[0177] The control unit 100 includes a main control unit 101 and a storage unit 102. The functions of the main control unit 101 are realized by, for example, a processor. The storage unit 102 stores in advance computer programs for controlling the ophthalmic apparatus 1. These computer programs include an illumination optical system control program, an imaging optical system control program, an optical scanner control program, an anterior eye imaging system control program, an image formation program, a data processing program, and a user interface program. The main control unit 101 operates in accordance with these computer programs, causing the control unit 100 to execute control processing.

[0178] (Main control unit 101) The main control unit 101 controls the objective optical system 20 (objective system moving mechanism 20D), the illumination optical system 30, the photographing optical systems 40L and 40R, the fixation projection systems 60L and 60R, the optical path switching member 70, the anterior eye photographing systems 80L and 80R, and the moving mechanism 10D. Furthermore, the main control unit 101 controls the image forming unit 200, the data processing unit 210, and the user interface (UI) unit 220.

[0179] The control of the objective optical system 20 includes control of the objective system moving mechanism 20D.

[0180] The objective system moving mechanism 20D includes a rotation mechanism for rotating the first elliptical concave mirror 21 and the second elliptical concave mirror 22 around a predetermined rotation axis, and a slide mechanism for sliding the optical systems of the optical system 10 excluding the objective optical system 20 as shown in Fig. 5 in conjunction with the rotation of the rotation mechanism. Each movement mechanism includes a pulse motor as an actuator, and under the control of the main control unit 101, rotates the first elliptical concave mirror 21 and the second elliptical concave mirror 22 using the rotation mechanism and slides the above-mentioned optical systems using the slide mechanism.

[0181] The control of the illumination optical system 30 includes control of the light source unit 31, control of the moving mechanism 34D, control of the optical scanner 95, and the like.

[0182] The control of the light source unit 31 includes turning on / off and adjusting the light intensity of each of the visible light sources 312R, 312G, 312B and the infrared light source 312IR.

[0183] The moving mechanism 34D moves the slit 34 in the optical axis direction of the illumination optical system 30. The main control unit 101 outputs a control signal to the moving mechanism 34D, thereby moving the slit 34 by an amount and in a direction corresponding to the control signal.

[0184] The movement mechanism 34D also includes a rotation mechanism that changes the angle at which the exit surface of the slit 34 intersects with the optical axis of the illumination optical system 30. The rotation mechanism rotates the slit 34 about a rotation axis that is perpendicular to the optical axis of the illumination optical system 30. In the left-eye photography mode, the movement mechanism 34D receives control from the main controller 101 and rotates the slit 34 so that the longitudinal direction of the slit 34 is optically approximately parallel to the major axis direction of the first elliptical concave mirror 21 in the first rotation state shown in FIG. 6A. In the right-eye photography mode, the movement mechanism 34D receives control from the main controller 101 and rotates the slit 34 so that the longitudinal direction of the slit 34 is optically approximately parallel to the major axis direction of the first elliptical concave mirror 21 in the second rotation state shown in FIG. 6B.

[0185] In some embodiments, a first slit having a fixed intersection angle is provided for the left eye photography mode, and a second slit having a fixed intersection angle is provided for the right eye photography mode. In this case, the moving mechanism 34D is configured to position either the first slit or the second slit on the optical axis of the illumination optical system 30 under the control of the main control unit 101.

[0186] For example, the ophthalmologic apparatus 1 is provided with an actuator that generates a driving force for driving the moving mechanism 34D and a transmission mechanism that transmits this driving force. The actuator is configured, for example, by a pulse motor. The transmission mechanism is configured, for example, by a combination of gears or a rack-and-pinion. The moving mechanism 34D receives, from the transmission mechanism, the driving force generated by the actuator under the control of the main controller 101, and moves the slit 34 in the optical axis direction and rotates around the rotation axis.

[0187] Control of the optical scanner 95 includes control of the angle of the deflection surface that deflects the illumination light. By controlling the angle of the deflection surface, it is possible to control the deflection direction (scan direction) of the illumination light. By controlling the angle range of the deflection surface, it is possible to control the scan range (scan start position and scan end position). By controlling the speed at which the angle of the deflection surface is changed, it is possible to control the scan speed.

[0188] The control of the optical path switching member 70 includes optical path switching control according to the imaging mode. In the left eye imaging mode, the optical path switching member 70 is controlled by the main control unit 101 and guides the illumination light deflected by the optical scanner 95 to the optical path separating member 50L. In the right eye imaging mode, the optical path switching member 70 is controlled by the main control unit 101 and guides the illumination light deflected by the optical scanner 95 to the optical path separating member 50R.

[0189] Control over the photographing optical system 40L includes control over the image sensor 47L, control over the focusing mechanism 40Ld, etc. Control over the photographing optical system 40R includes control over the image sensor 47R, control over the focusing mechanism 40Rd, etc.

[0190] Control of the image sensors 47L and 47R includes setting control of the light-receiving area on the light-receiving surface and control for reading out the light-receiving results using a rolling shutter method (for example, setting the light-receiving size corresponding to the size of the illumination pattern). Control of the image sensors 47L and 47R also includes reset control, exposure control, charge transfer control, output control, etc.

[0191] The focusing mechanisms 40Ld, 40Rd move the photographing optical systems 40L, 40R in the optical axis direction. The main controller 101 outputs control signals to the focusing mechanisms 40Ld, 40Rd, thereby moving the photographing optical systems 40L, 40R by an amount and in a direction corresponding to the control signal. For example, the ophthalmic apparatus 1 is provided with an actuator that generates a driving force for driving the focusing mechanisms 40Ld, 40Rd, and a transmission mechanism that transmits this driving force. The actuator is, for example, a pulse motor. The transmission mechanism is, for example, a combination of gears or a rack-and-pinion. The focusing mechanisms 40Ld, 40Rd move the photographing optical systems 40L, 40R in the optical axis direction by receiving the driving force generated by the actuator under the control of the main controller 101.

[0192] Control of the fixation projection systems 60L and 60R includes control of the fixation light sources 61L and 61R.

[0193] Control of the fixation light sources 61L and 61R includes turning the light sources on and off, adjusting the light intensity, and the like.

[0194] Control of the anterior eye imaging systems 80L and 80R includes control to position the light receiving surfaces of the anterior eye cameras 81LL and 81LR at a position conjugate with the fundus of the left eye EL, and imaging control of the anterior eye cameras 81LL and 81LR.Furthermore, control of the anterior eye imaging systems 80L and 80R includes control to position the light receiving surfaces of the anterior eye cameras 81RL and 81RR at a position conjugate with the fundus of the right eye ER, and imaging control of the anterior eye cameras 81RL and 81RR.

[0195] The control of positioning the light receiving surfaces of the anterior eye cameras 81LL and 81LR at a position conjugate with the fundus of the left eye EL includes control of moving the anterior eye cameras 81LL and 81LR, or control of moving the focusing lens that transmits light from the left eye EL in the optical axis direction. The control of photographing the anterior eye cameras 81LL and 81LR includes control of the light receiving sensitivity of each camera, control of the frame rate (light receiving timing), and control of synchronization between the two cameras.

[0196] The control of positioning the anterior eye cameras 81RL and 81RR at positions conjugate with the fundus of the right eye ER includes control of moving the light receiving surfaces of the anterior eye cameras 81RL and 81RR, or control of moving the focusing lens that transmits light from the right eye ER in the optical axis direction. The control of photographing the anterior eye cameras 81RL and 81RR includes control of the light receiving sensitivity of each camera, control of the frame rate (light receiving timing), and control of synchronization between the two cameras.

[0197] The movement mechanism 10D three-dimensionally moves the optical system 10 (apparatus optical system) of the ophthalmologic apparatus 1 shown in FIG. 1. In a typical example, the movement mechanism 10D includes a mechanism for moving the optical system 10 (a housing that houses the optical system 10) in the X direction (left-right direction), a mechanism for moving it in the Y direction (up-down direction), and a mechanism for moving it in the Z direction (depth direction, front-back direction, working distance direction). The mechanism for moving it in the X direction includes, for example, an X stage that can move in the X direction and an X movement mechanism that moves the X stage. The mechanism for moving it in the Y direction includes, for example, a Y stage that can move in the Y direction and a Y movement mechanism that moves the Y stage. The mechanism for moving it in the Z direction includes, for example, a Z stage that can move in the Z direction and a Z movement mechanism that moves the Z stage. Each movement mechanism includes a pulse motor as an actuator and operates under the control of the main control unit 101.

[0198] Control of the movement mechanism 10D is used for alignment and tracking. Tracking is the act of moving the device optical system in accordance with the eye movement of the subject's eye being imaged. Before tracking can be performed, alignment and focus adjustment are performed. Tracking is a function that maintains an optimal positional relationship where alignment and focus are achieved by making the position of the device optical system follow the eye movement.

[0199] In the case of manual alignment, the user moves the optical system 10 and the subject's eye relative to each other by operating the UI unit 220 so that the displacement of the subject's eye, which is the subject of imaging, relative to the optical system is canceled. For example, the main control unit 101 controls the moving mechanism 10D by outputting a control signal corresponding to the operation content on the UI unit 220 to the moving mechanism 10D, thereby moving the optical system relative to the subject's eye.

[0200] In the case of auto-alignment, the main controller 101 controls the moving mechanism 10D to move the optical system relative to the subject's eye so that displacement of the subject's eye relative to the optical system is canceled. Specifically, as described in JP 2013-248376 A, calculation processing is performed using trigonometry based on the positional relationship between the subject's eye and two anterior-segment cameras of the anterior-segment imaging system 80L or the anterior-segment imaging system 80R. The main controller 101 controls the moving mechanism 10D so that the subject's eye is positioned relative to the optical system in a predetermined manner.

[0201] The control of the image forming unit 200 includes image formation control for forming an image for the left eye EL or the right eye ER from the light reception results obtained by the image sensor 47L or the image sensor 47R.

[0202] Control over the data processing unit 210 includes image processing control of images acquired by the imaging optical systems 40L and 40R, analysis processing control of images acquired by the anterior segment imaging systems 80L and 80R, and alignment control of the device optical system relative to the subject's eye.

[0203] The control over the UI unit 220 includes control over the display device, control over the operation device (input device), and the like.

[0204] (Storage unit 102) The storage unit 102 stores various types of data. Examples of the data stored in the storage unit 102 include light reception results obtained by the image sensors 47L and 47R, image data of images formed by the image forming unit 200, processing results obtained by the data processing unit 210, and information about the subject's eye. The information about the subject's eye includes information about the subject, such as a patient ID and name, and information about the subject's eye, such as identification information for the left eye or right eye.

[0205] The storage unit 102 also stores various programs and data for operating the ophthalmologic apparatus 1.

[0206] (Image forming unit 200) The image forming unit 200 is capable of forming a light receiving image corresponding to any aperture range based on the light receiving results read out from the image sensor 47L or the image sensor 47R by a rolling shutter method under the control of the main control unit 101 (control unit 100). The image forming unit 200 is capable of sequentially forming light receiving images corresponding to (virtual) aperture ranges and forming an image of the left eye EL or the right eye ER from the formed plurality of light receiving images. Various images (image data) formed by the image forming unit 200 are stored in, for example, the memory unit 102.

[0207] For example, the image forming unit 200 includes a processor, and performs processing according to a program stored in a storage unit or the like, thereby realizing the above functions.

[0208] (Data processing unit 210) The data processing unit 210 performs various image processing, analysis processing, and alignment processing on the light reception results obtained from the image sensors 47L and 47R. The image processing includes noise removal processing on the light reception results and brightness correction processing to make it easier to identify specific areas depicted in the light reception image based on the light reception results. The alignment processing includes processing to align the device optical system with the subject's eye.

[0209] The data processing unit 210 includes a processor, and performs processing in accordance with a program stored in a storage unit or the like to realize the above functions.

[0210] FIG. 20 shows a block diagram of an example of the configuration of the data processing unit 210 in FIG.

[0211] The data processing unit 210 includes a pupil region specifying unit 211 , a three-dimensional position specifying unit 212 , and an alignment target position specifying unit 213 .

[0212] The pupil region specifying unit 211 acquires a pair of anterior eye images (photographed images) of the left eye EL obtained by substantially simultaneously photographing the anterior eye cameras 81LL and 81LR of the anterior eye imaging system 80L. The pupil region specifying unit 211 analyzes each of the pair of acquired anterior eye images to specify the position of the pupil region (center position, center of gravity position) in the anterior eye images corresponding to the pupil of the left eye EL.

[0213] First, the pupil region identification unit 211 identifies an image region (pupil region) corresponding to the pupil of the left eye EL based on the distribution of pixel values ​​(such as brightness values) of the anterior eye image. Since the pupil is generally depicted with lower brightness than other parts, the pupil region can be identified by searching for an image region with low brightness. At this time, the pupil region may be identified taking into consideration the shape of the pupil. In other words, the pupil region can be identified by searching for an image region with a substantially circular shape and low brightness.

[0214] Next, pupil region specifying unit 211 specifies the center position of the specified pupil region. Because the pupil is approximately circular as described above, the outline of the pupil region is specified, and the center position of this outline (an approximate circle or ellipse) is specified, and this can be used as the pupil center position. Alternatively, the center of gravity of the pupil region may be found, and this center position may be specified as the pupil center position.

[0215] Similarly, the pupil region specifying unit 211 acquires a pair of anterior eye images of the right eye ER obtained by substantially simultaneously capturing images using the anterior eye cameras 81RL and 81RR of the anterior eye imaging system 80R. The pupil region specifying unit 211 analyzes each of the pair of acquired anterior eye images to specify the position of the pupil region in the anterior eye images that corresponds to the pupil of the right eye ER, similar to the pupil region of the left eye EL.

[0216] The pupil region specifying unit 211 can sequentially specify a pupil region corresponding to the pupil for a pair of anterior eye images sequentially obtained by the anterior eye cameras 81LL and 81LR or the anterior eye cameras 81RL and 81RR. The pupil region specifying unit 211 may also specify a pupil region for every other arbitrary number of frames (one or more) for a pair of anterior eye images sequentially obtained by the anterior eye cameras 81LL and 81LR or the anterior eye cameras 81RL and 81RR.

[0217] The three-dimensional position identifying unit 212 identifies the three-dimensional position of the pupil of the left eye EL based on the positions of the anterior-segment cameras 81LL and 81LR and the pupil region (center position) identified by the pupil region identifying unit 211. As disclosed in Japanese Patent Application Laid-Open No. 2013-248376, the three-dimensional position identifying unit 212 applies known trigonometry to the positions (known) of the two anterior-segment cameras 81LL and 81LR and the position corresponding to the pupil region in the pair of anterior-segment images. This allows the three-dimensional position identifying unit 212 to calculate the three-dimensional position of the pupil of the left eye EL as the three-dimensional position of the left eye EL.

[0218] Furthermore, the three-dimensional position specifying unit 212 specifies the three-dimensional position of the pupil of the right eye ER based on the positions of the anterior eye cameras 81RL and 81RR and the pupil region (center position) specified by the pupil region specifying unit 211. The three-dimensional position specifying unit 212 calculates the three-dimensional position of the pupil of the right eye ER as the three-dimensional position of the right eye ER by applying known trigonometry to the positions (known) of the two anterior eye cameras 81RL and 81RR and the position corresponding to the pupil region in the pair of anterior eye images.

[0219] The alignment target position specifying unit 213 specifies the alignment target position (Xr, Yr, Zr). The alignment target position (Xr, Yr, Zr) is a three-dimensional position defined in a three-dimensional coordinate system with a predetermined reference position in the optical system of the ophthalmologic apparatus 1 as the origin. The X-direction coordinate position Xr and the Y-direction coordinate position Yr of the alignment target position are positions on the XY plane where the optical axis of the photographing optical system 40L approximately coincides with the axis of the left eye EL, or positions on the XY plane where the optical axis of the photographing optical system 40R approximately coincides with the axis of the right eye ER. The Z-direction coordinate position Zr of the alignment target position is a position on the optical axis of the photographing optical system 40L where the distance of the optical system 10 to the left eye EL is a predetermined working distance, or a position on the optical axis of the photographing optical system 40R where the distance of the optical system 10 to the right eye ER is a predetermined working distance. Here, the working distance is a predetermined value also called the working distance of the objective optical system 20, and corresponds to the distance between the subject's eye and the optical system 10 during measurement (photography) using the photographing optical systems 40L and 40R.

[0220] The main control unit 101 controls the moving mechanism 10D so that the subject's eye, which is the subject of imaging, is positioned at the alignment target position calculated by the alignment target position specifying unit 213.

[0221] (UI section 220) The UI unit 220 has a function for exchanging information between a user (examiner or subject) and the ophthalmologic apparatus 1. The UI unit 220 includes a display device and an operation device. The display device may include a display unit or other display devices. The display device displays various types of information. The display device includes, for example, a liquid crystal display, and displays the information under control of the main control unit 101. Information displayed on the display device includes information corresponding to the control results by the control unit 100, information (images) corresponding to the calculation results by the image forming unit 200 or the data processing unit 210, etc. The operation device includes various hardware keys and / or software keys. The main control unit 101 can receive operation details for the operation device and output control signals corresponding to the operation details to each unit. At least a part of the operation device and at least a part of the display device can be configured integrally. A touch panel display is one example.

[0222] <Example of operation> Next, an example of the operation of the ophthalmologic apparatus 1 according to the embodiment will be described.

[0223] 21 to 23 show an example of operation of the ophthalmologic apparatus 1 according to the embodiment. FIG. 21 shows a flowchart of the example of operation of the ophthalmologic apparatus 1 according to the embodiment. FIG. 22 shows a flowchart of the example of operation of steps S5 and S11 in FIG. 21. FIG. 23 shows a flowchart of the example of operation of steps S6 and S12 in FIG. 21. The storage unit 102 stores a computer program for realizing the processes shown in FIGS. 21 to 23. The main control unit 101 operates in accordance with this computer program to execute the processes shown in FIGS. 21 to 23.

[0224] (S1: Left eye shooting mode?) First, the main control unit 101 determines whether the imaging mode is the left eye imaging mode. For example, the main control unit 101 determines the type of imaging mode based on the operation content of the UI unit 220 by the user.

[0225] When it is determined that the photographing mode is the left eye photographing mode (S1: Y), the operation of the ophthalmologic apparatus 1 proceeds to step S2, and slit photographing control is executed for the left eye EL in steps S2 to S6. When it is determined that the photographing mode is not the left eye photographing mode (S1: N), the operation of the ophthalmologic apparatus 1 proceeds to step S7.

[0226] (S2: Switch the optical path of the illumination light) When it is determined in step S1 that the photographing mode is the left eye photographing mode (S1: Y), the main control unit 101 controls the optical path switching member 70 to switch the optical path so that the illumination light is guided to the optical path separating member 50L.

[0227] (S3: Changed slit arrangement) Next, the main control unit 101 controls the movement mechanism 34D to change the intersection angle of the slit 34 with the optical axis so that the exit surface of the slit 34 is optically approximately parallel to the major axis direction of the first elliptical concave mirror 21 shown in Figure 6A.

[0228] (S4: Start irradiating the illumination light) Next, the main control unit 101 controls the light source unit 31 to start emitting illumination light. For example, the light source unit 31 starts emitting white light or infrared light as illumination light.

[0229] (S5: Alignment process) Next, the main controller 101 uses the anterior eye imaging system 80L to perform alignment processing of the optical system 10 with respect to the left eye EL. Details of step S5 will be described later.

[0230] (S6: Slit photography) Next, the main control unit 101 performs a photographing process on the fundus of the left eye EL using the slit scan method. Details of step S6 will be described later.

[0231] (S7: Right eye shooting mode?) When it is determined in step S1 that the shooting mode is not the left eye shooting mode (S1: N), or following step S6, the main control unit 101 determines whether the shooting mode is the right eye shooting mode. For example, the main control unit 101 determines the type of shooting mode based on the operation content of the user on the UI unit 220.

[0232] When it is determined that the photography mode is the right eye photography mode (S7: Y), the operation of the ophthalmologic apparatus 1 proceeds to step S8, and slit photography control is executed for the right eye ER in steps S8 to S12. When it is determined that the photography mode is not the right eye photography mode (S7: N), the operation of the ophthalmologic apparatus 1 ends (END).

[0233] (S8: Switch the optical path of the illumination light) When it is determined in step S7 that the photography mode is the right eye photography mode (S7: Y), the main control unit 101 controls the optical path switching member 70 to switch the optical path so that the illumination light is guided to the optical path separating member 50R.

[0234] (S9: Changed slit arrangement) Next, the main control unit 101 controls the movement mechanism 34D to change the intersection angle of the slit 34 with the optical axis so that the exit surface of the slit 34 is optically approximately parallel to the major axis direction of the first elliptical concave mirror 21 shown in Figure 6B.

[0235] (S10: Start irradiating the illumination light) Next, the main control unit 101 controls the light source unit 31 to start emitting illumination light, similarly to step S4.

[0236] (S11: Alignment process) Next, the main controller 101 executes alignment processing of the optical system 10 with respect to the right eye ER using the anterior eye imaging system 80R. Step S11 is the same as step S5, except that the anterior eye imaging system 80R is used instead of the anterior eye imaging system 80L.

[0237] (S12: Slit photography) Next, the main controller 101 performs photographing processing on the fundus of the right eye ER by the slit scan method. Step S12 is the same as step S6 except that the photographing optical system 40R is used instead of the photographing optical system 40L.

[0238] This is the end of the operation of the ophthalmologic apparatus 1 (END).

[0239] The processing of step S5 or step S11 in Fig. 21 is performed according to the flow shown in Fig. 22. In Fig. 22, the processing of step S5 will be described for the left eye EL, but since the processing of step S11 for the right eye ER is similar, a detailed description of the processing of step S11 will be omitted.

[0240] In FIG. 22, it is assumed that prior to step S21, the anterior eye cameras 81LL and 81LR of the anterior eye photographing system 80L have already been placed at positions conjugate with the fundus of the left eye EL.

[0241] (S21: Photographing the anterior segment) In step S5, first, the main control unit 101 controls the anterior eye cameras 81LL and 81LR of the anterior eye photography system 80L to start photographing the anterior eye of the left eye EL from different directions, and starts acquiring a pair of anterior eye images of the left eye EL that are acquired substantially simultaneously.

[0242] (S22: Identify the pupil area) Next, the main control unit 101 controls the pupil region specifying unit 211 to specify the pupil region for each of the pair of anterior eye images acquired in step S21.

[0243] (S23: Calculate the 3D position of the pupil area) Next, the main control unit 101 controls the three-dimensional position identification unit 212 to calculate the three-dimensional position of the pupil region of the left eye EL as described above, using the pupil region in the pair of anterior eye images identified in step S22.

[0244] (S24: Identify alignment target position) Next, the main control unit 101 controls the alignment target position specifying unit 213 to specify the alignment target position based on the three-dimensional position of the pupil region calculated in step S23 as described above.

[0245] (S25: Control the moving mechanism) Next, the main controller 101 controls the moving mechanism 10D to move the optical system 10 relative to the left eye EL based on the alignment target position calculated in step S25.

[0246] This is the end of the processing in step S5 (END).

[0247] The processing of step S6 or step S12 in Fig. 21 is performed according to the flow shown in Fig. 23. In Fig. 23, the processing of step S6 will be described for the left eye EL, but since the processing of step S12 for the right eye ER is similar, a detailed description of the processing of step S12 will be omitted.

[0248] (S31: Obtain diopter) In step S6, first, the main controller 101 acquires the diopter (refractive power). For example, the main controller 101 acquires the diopter of the left eye EL from an external ophthalmic measurement device or an electronic medical chart. In some embodiments, the main controller 101 controls the focusing mechanism 40Ld to identify the in-focus state, and identifies the diopter from the position on the optical axis of the imaging optical system 40L set to the in-focus state (or the control result of the actuator that drives the focusing mechanism 40Ld).

[0249] (S32: Move the slit) Next, the main controller 101 changes the position of the slit 34 on the optical axis of the illumination optical system 30 according to the diopter of the left eye EL acquired in step S31.

[0250] Specifically, the main control unit 101 identifies the position of the slit 34 corresponding to the diopter by referring to the first control information stored in the memory unit 102, and controls the moving mechanism 34D so that the slit 34 is positioned at the identified position.

[0251] (S33: Projects fixation beam) Next, the main controller 101 controls the fixation projection system 60L to start projecting a fixation light beam onto the fundus of the left eye EL.

[0252] (S34: Illumination light is emitted) Next, the main controller 101 starts irradiating the desired irradiation range of the fundus of the left eye EL with the illumination light by starting deflection control of the optical scanner 95 for the slit-shaped illumination light generated by the illumination optical system 30. When irradiation of the illumination light starts, the slit-shaped illumination light is sequentially irradiated within the desired irradiation range as described above.

[0253] (S35: Obtain light reception results) As described above, the main controller 101 acquires the light reception results of the pixels in the aperture range of the image sensor 47L corresponding to the irradiation range of the illumination light on the fundus in step S34.

[0254] (S36: Next irradiation position?) The main controller 101 determines whether there is a next irradiation position to be irradiated with illumination light. The main controller 101 can determine whether there is a next irradiation position to be irradiated with illumination light by determining whether the irradiation range of the illumination light, which is sequentially moved, covers a predetermined fundus photography range.

[0255] When it is determined that there is a position to be irradiated with the illumination light next (S36: Y), the operation of the ophthalmic apparatus 1 proceeds to step S37. When it is determined that there is no position to be irradiated with the illumination light next (S36: N), the operation of the ophthalmic apparatus 1 proceeds to step S38.

[0256] (S37: Change the deflection angle of the illumination light) When it is determined in step S36 that there is a next irradiation position to be irradiated with illumination light (S36: Y), the main control unit 101 controls the optical scanner 95 to change the deflection angle of the deflection surface of the optical scanner 95 by a predetermined angle.

[0257] Following step S37, the process of step S6 proceeds to step S34.

[0258] (S38: Form an image) In step S36, when it is determined that there is no irradiation position to be irradiated with the illumination light next (S36: N), the main control unit 101 causes the image forming unit 200 to form a fundus image of the left eye EL from the light reception results repeatedly acquired while changing the irradiation range of the illumination light in steps S34 to S37.

[0259] For example, the image forming unit 200 combines a plurality of light receiving results, each having different illumination light irradiation ranges (opening ranges on the light receiving surface of the image sensor 47L), for the number of times the processes of steps S34 to S37 are repeated, based on the order in which the irradiation ranges are moved, thereby forming one frame of a fundus image of the fundus of the left eye EL.

[0260] In some embodiments, in step S34, illumination light is applied to an illumination area set to provide an overlapping area with an adjacent illumination area, and thus, in step S38, one frame of fundus image is formed by combining the fundus images so that the overlapping areas overlap each other.

[0261] This is the end of the process in step S6 in FIG. 21 (END).

[0262] FIG. 24 is a schematic diagram showing the fundus of the subject's eye to be photographed.

[0263] A slit image (an image of the opening 34a formed in the slit 34) is projected onto the fundus Ef of the left eye EL or right eye ER to be photographed. In the image sensor 47L or the image sensor 47R, the position of the virtual light-receiving area on the light-receiving surface is changed in synchronization with the movement of the slit image, which corresponds to the illumination area of ​​the illumination light on the fundus Ef.

[0264] Specifically, the light-receiving area of ​​the image sensor 47L or 47R is set corresponding to the illumination area of ​​the fundus Ef so as to include the range of the slit image on the fundus Ef. The slit image is scanned so as to move in the short direction perpendicular to the long direction of the slit image. For example, when the deflection angle is "0 degrees," a slit image SL10 corresponding to the illumination area on the fundus Ef is projected. At this time, the image sensor 47L or 47R sets a light-receiving area LA10 corresponding to this illumination area. Thereafter, when the deflection angle is changed to "+α degrees," a slit image SL11 corresponding to the illumination area on the fundus Ef is projected. At this time, the image sensor 47L or 47R sets a light-receiving area LA11 corresponding to this illumination area. Furthermore, when the deflection angle is changed to "-α degrees," a slit image SL12 corresponding to the illumination area on the fundus Ef is projected. At this time, the image sensor 47L or 47R sets a light-receiving area LA12 corresponding to this illumination area. In this way, in synchronization with the movement of the slit image on the fundus oculi Ef, the image sensor 47L or 47R sequentially moves the light-receiving area on the light-receiving surface so as to include the range of the slit image.

[0265] According to the embodiment, regardless of the movement range of the slit image, it is possible to eliminate uneven illumination in the peripheral area of ​​the movement range, thereby making it possible to acquire a wide-angle, high-quality image of the subject's eye even when using an optical system that requires higher resolution.

[0266] In the above embodiment, the case where the objective optical system 20 is shared between the left eye imaging mode and the right eye imaging mode has been described, but the configuration according to the embodiment is not limited to this. For example, an objective optical system for the left eye imaging mode and an objective optical system for the right eye imaging mode may be provided. In this case, two elliptical concave mirrors (e.g., the first elliptical concave mirror 21 and the second elliptical concave mirror 22) are provided for imaging or measuring the left eye EL, and two elliptical concave mirrors (e.g., the first elliptical concave mirror 21′ and the second elliptical concave mirror 22′) are provided for imaging or measuring the right eye ER.

[0267] In the above embodiment, the imaging optical systems 40L and 40R may be a single imaging optical system shared by the left eye EL and the right eye ER. Also, the fixation projection systems 60L and 60R may be a single fixation projection system shared by the left eye EL and the right eye ER. The anterior eye imaging systems 80L and 80R may be a single anterior eye imaging system shared by the left eye EL and the right eye ER.

[0268] In the above embodiment, the angles formed between the measurement conjugate plane and the imaging optical axis at a position optically approximately conjugate with the measurement position of the two or more cameras in each anterior segment imaging system may not be the same. The two or more cameras may be arranged asymmetrically with respect to the normal direction of the measurement conjugate plane (so that the angles formed between the normal direction and the imaging optical axis are different).

[0269] Furthermore, in the above embodiment, a case where the dichroic mirror 90L or the dichroic mirror 90R is disposed between the first elliptical concave mirror 21 and the optical path separating member 50L or the optical path separating member 50R has been described, but the embodiment is not limited thereto. For example, in the left eye imaging mode, the dichroic mirror 90L may be disposed between the first elliptical concave mirror 21 and the second elliptical concave mirror 22 shown in FIG. 6A. In this case, the anterior eye imaging system 80L can be positioned so as to view the second focal point F2 (primary left eye measurement conjugate position) of the first elliptical concave mirror 21. Similarly, in the right eye imaging mode, for example, the dichroic mirror 90R may be disposed between the first elliptical concave mirror 21 and the second elliptical concave mirror 22 shown in FIG. 6B. In this case, the anterior eye imaging system 80R can be positioned so as to view the second focal point F2′ (primary right eye measurement conjugate position) of the first elliptical concave mirror 21.

[0270] [Effect] An ophthalmologic apparatus according to an embodiment will be described.

[0271] A first aspect of the embodiment is an ophthalmologic apparatus (1) including two or more curved mirrors (a first elliptical concave mirror 21, a second elliptical concave mirror 22), an illumination optical system (30), and imaging optical systems (40L, 40R). The illumination optical system includes a slit (34) having an opening (34a) formed therein, configured to be positioned at a fundus conjugate position that is approximately optically conjugate with the fundus (Ef) of the subject's eye (left eye EL, right eye ER). The illumination optical system irradiates the slit with light from a light source (light source unit 31), thereby generating slit-shaped illumination light, which is then irradiated onto the fundus via the two or more curved mirrors. The imaging optical system includes image sensors (47L, 47R) configured to be positioned at a fundus conjugate position and which receive return light from the subject's eye via the two or more curved mirrors. The openings are formed so that their widths in the short side direction (BW) vary depending on their positions in the long side direction (SD).

[0272] According to this aspect, it is possible to eliminate uneven illumination in the peripheral area of ​​the illumination range of the illumination light on the fundus, and therefore it is possible to acquire a wide-angle, high-quality image of the subject's eye.

[0273] In a second aspect of the embodiment, in the first aspect, the opening is formed so that the width (ΔM1) in the short side direction at a first end (UP) of one of the longitudinal end portions is larger than the width (ΔM2) in the short side direction at a second end (DW) of the other of the longitudinal end portions.

[0274] According to this aspect, it is possible to eliminate uneven illumination in the peripheral area with a simple configuration and obtain a wide-angle, high-quality image of the subject's eye.

[0275] In a third aspect of the embodiment, in the second aspect, the opening is formed so that the width in the short side direction at a first position in the longitudinal direction is less than the width in the short side direction at a second position closer to the first end than the first position.

[0276] According to this aspect, the width in the short direction increases from the second end to the first end, thereby reducing the effect of aberration at the position corresponding to the first end, thereby eliminating uneven illumination in the peripheral area and making it possible to obtain a wide-angle, high-quality image of the test eye.

[0277] In a fourth aspect of the embodiment, in the second or third aspect, the opening is formed so that the width in the short side direction at the second end is minimum.

[0278] According to this aspect, it is possible to eliminate uneven illumination in the peripheral area with a simpler configuration and to acquire a wide-angle, high-quality image of the subject's eye.

[0279] In a fifth aspect of the embodiment, in any one of the second to fourth aspects, the first end is displaced in the lateral direction with respect to the longitudinal direction passing through the center of the opening.

[0280] According to this aspect, it is possible to eliminate or reduce distortion in the image of the slit opening projected onto the fundus, thereby improving the contrast of the image acquired by the image sensor.

[0281] In a sixth aspect of the embodiment, in the fifth aspect, the opening includes a portion that changes in a curved shape from the center of the opening toward the first end.

[0282] According to this aspect, it is possible to further improve the contrast of the image acquired by the image sensor.

[0283] A seventh aspect of the embodiment is any one of the first to sixth aspects, wherein each of the two or more curved mirrors has one or more focal points and is arranged so as to share at least one of the two or more focal points.

[0284] According to this aspect, the illumination light is guided to the eye to be examined by two or more curved mirrors, so that a wider-angle image of the eye to be examined can be obtained with a simple configuration.

[0285] In an eighth aspect of the embodiment, in the seventh aspect, the two or more curved mirrors include an elliptical concave mirror (first elliptical concave mirror 21 or second elliptical concave mirror 22).

[0286] According to this aspect, it is possible to obtain a wider-angle image of the subject's eye with a simple configuration using an elliptical concave mirror.

[0287] In a ninth aspect of the embodiment, in the eighth aspect, the two or more curved mirrors are a first elliptical concave mirror (21) and a second elliptical concave mirror (22). A first focal point (F1) of the first elliptical concave mirror is arranged at a position that is approximately optically conjugate with a measurement position where the pupil of the subject's eye can be placed (left eye measurement conjugate position, right eye measurement conjugate position). A second focal point (F2) of the first elliptical concave mirror approximately coincides with a third focal point (first focal point F3) of the second elliptical concave mirror, and a fourth focal point (second focal point F4) of the second elliptical concave mirror is configured to be arranged at the measurement position.

[0288] According to this aspect, it becomes possible to acquire a wider-angle image of the subject's eye using the first elliptical concave mirror and the second elliptical concave mirror.

[0289] In a tenth aspect of the embodiment, in the ninth aspect, the first end is an end on the side of the first focal point on the long axis of the first elliptical concave mirror, and the second end is an end on the side of the second focal point on the long axis.

[0290] According to this aspect, by reducing the influence of aberration at the position corresponding to the first end of the first elliptical concave mirror, it becomes possible to obtain a wider-angle, higher-quality image of the test eye using the first elliptical concave mirror and the second elliptical concave mirror.

[0291] In an eleventh aspect of the embodiment, in the ninth or tenth aspect, the longitudinal direction is the long axis direction of the first elliptical concave mirror.

[0292] According to this aspect, it is possible to reduce the influence of aberration in the short-side direction perpendicular to the long-axis direction of the first elliptical concave mirror, and to acquire a wider-angle, high-quality image of the subject's eye.

[0293] In a twelfth aspect of the embodiment, in any of the seventh to eleventh aspects, the illumination optical system includes an optical scanner (95) configured to be placed at an iris conjugate position that is optically approximately conjugate with the iris of the subject's eye. The ophthalmologic apparatus is configured to be able to move the illumination position of the fundus by the illumination light by deflecting the illumination light with the optical scanner.

[0294] According to this aspect, it is possible to obtain a high-quality image of the fundus of the subject's eye with a simple configuration by controlling the deflection of the illumination light using the optical scanner.

[0295] In a thirteenth aspect of the embodiment, in any one of the first to twelfth aspects, the image sensor is a rolling shutter type image sensor.

[0296] According to this aspect, it is possible to acquire a higher quality image of the fundus with a simple configuration.

[0297] In a fourteenth aspect of the embodiment, in any one of the first to thirteenth aspects, the slit is movable in the direction of the optical axis of the illumination optical system according to the diopter of the eye to be examined.

[0298] According to this aspect, it is possible to illuminate the fundus with high-intensity illumination light regardless of the diopter of the subject's eye.

[0299] A fifteenth aspect of the embodiment is any of the first to fourteenth aspects, and further includes two or more cameras (anterior-segment cameras 81LL, 81LR, or anterior-segment cameras 81RL, 81RR), a moving mechanism (10D), and a three-dimensional position specifying unit (212). The two or more cameras are arranged so that an iris conjugate position that is approximately optically conjugate with the iris of the subject's eye relayed by the two or more curved mirrors is included in the field of view. The moving mechanism moves the two or more curved mirrors, the illumination optical system, the imaging optical system, and the two or more cameras relative to the subject's eye. The three-dimensional position specifying unit specifies the three-dimensional position of the subject's eye based on two or more anterior-segment images of the subject's eye obtained by the two or more cameras.

[0300] According to this aspect, two or more anterior segment images of the subject's eye can be acquired, and the alignment between the optical system and the subject's eye can be suitably performed based on the acquired two or more anterior segment images, thereby enabling high-resolution wide-angle photography or high-precision measurement of the subject's eye.

[0301] A sixteenth aspect of the embodiment is the fifteenth aspect, further comprising reflecting members (51L, 51R) and photographic diaphragms (52L, 52R). The reflecting members are arranged at a position conjugate with the iris. The photographic diaphragm is arranged at a position conjugate with the iris, and has an aperture formed at a position eccentric from the optical axis. The reflecting members reflect illumination light from the illumination optical system and guide it to two or more curved mirrors. The photographic diaphragm guides returning light that has passed through the aperture to the photographic optical system.

[0302] According to this aspect, the optical path of the illumination optical system and the optical path of the photographing optical system are separated using a reflecting member and a photographing aperture, so that the size of the optical system can be reduced with a simple configuration.

[0303] <Other> The embodiment described above is merely one example for carrying out the present invention, and those who wish to carry out the present invention may make any modifications, omissions, additions, etc. within the scope of the gist of the present invention. [Explanation of symbols]

[0304] 1 Ophthalmology equipment 10 Optical system 10D moving mechanism 21 First elliptical concave mirror 22 Second elliptical concave mirror 30 Illumination optical system 31 Light source unit 32 Iris Diaphragm 34 Slit 40L, 40R imaging optical system 47L, 47R image sensors 50L, 50R Optical path separation member 70 Optical path switching member 80L, 80R Anterior segment imaging system 81LL, 81LR, 81RL, 81RR Anterior Segment Camera 90L, 90R Dichroic Mirror 95 Optical Scanner 100 control section 101 Main control unit 102 Storage section 200 Image forming unit 210 Data Processing Unit 211 Pupil area identification unit 212 3D position identification part 213 Alignment target position specifying unit BSL, BSR Beam Splitter BW Short side direction EL left eye ER right eye EW Exposure width F1, F3 1st focal point F2, F4 2nd focal point SD Longitudinal UP 1st end DW 2nd end

Claims

1. two or more curved mirrors; an illumination optical system including a slit having an opening formed therein configured to be positioned at a fundus conjugate position that is optically approximately conjugate with the fundus of the subject's eye, the illumination optical system irradiating the fundus with slit-shaped illumination light generated by irradiating the slit with light from a light source via the two or more curved mirrors; an imaging optical system including an image sensor configured to be disposed at a position conjugate with the fundus and configured to receive return light from the subject's eye via the two or more curved mirrors; Including, The ophthalmologic apparatus is configured such that the width of the opening in the lateral direction varies depending on the position in the longitudinal direction.

2. The opening is formed so that the width in the short side direction at a first end portion at one of both ends in the longitudinal direction is larger than the width in the short side direction at a second end portion at the other of both ends.

2. An ophthalmic apparatus according to claim 1.

3. The opening is formed so that the width in the lateral direction at a first position in the longitudinal direction is equal to or smaller than the width in the lateral direction at a second position closer to the first end than the first position.

3. An ophthalmic apparatus according to claim 2.

4. The opening is formed so that the width in the short side direction at the second end is minimum.

3. The ophthalmic apparatus according to claim 2, wherein:

5. The first end is displaced in the short-side direction with respect to the long-side direction passing through the center of the opening.

3. An ophthalmic apparatus according to claim 2.

6. The opening includes a portion that changes in a curved shape from the center of the opening toward the first end.

6. An ophthalmic apparatus according to claim 5.

7. Each of the two or more curved mirrors has one or more focal points and is arranged to share at least one of the two or more focal points. The ophthalmic apparatus according to any one of claims 2 to 6.

8. The two or more curved mirrors include an elliptical concave mirror.

8. An ophthalmic apparatus according to claim 7.

9. the two or more curved mirrors are a first elliptical concave mirror and a second elliptical concave mirror, a first focal point of the first elliptical concave mirror is disposed at a position that is optically approximately conjugate with a measurement position at which an iris of the subject's eye can be disposed; a second focal point of the first elliptical concave mirror substantially coincides with a third focal point of the second elliptical concave mirror; The fourth focal point of the second elliptical concave mirror is configured to be positioned at the measurement position.

9. An ophthalmic apparatus according to claim 8.

10. the first end is an end of the first elliptical concave mirror on a major axis thereof on the side of the first focal point, The second end is an end on the long axis on the side of the second focal point.

10. An ophthalmic apparatus according to claim 9.

11. The longitudinal direction is the long axis direction of the first elliptical concave mirror.

10. An ophthalmic apparatus according to claim 9.

12. The illumination optical system includes an optical scanner configured to be placed at an iris conjugate position that is optically approximately conjugate with the iris of the subject's eye, and is configured to be able to move the illumination position of the fundus by the illumination light by deflecting the illumination light with the optical scanner.

8. An ophthalmic apparatus according to claim 7.

13. The image sensor is a rolling shutter type image sensor. The ophthalmic apparatus according to claim 12 .

14. The slit is movable in the direction of the optical axis of the illumination optical system according to the diopter of the eye to be examined.

8. An ophthalmic apparatus according to claim 7.

15. two or more cameras arranged so that an iris conjugate position that is approximately optically conjugate with the iris of the subject's eye relayed by the two or more curved mirrors is included in a field of view; a moving mechanism that moves the two or more curved mirrors, the illumination optical system, the photographing optical system, and the two or more cameras relative to the eye to be examined; a three-dimensional position specifying unit that specifies a three-dimensional position of the subject's eye based on two or more anterior eye images of the subject's eye obtained by the two or more cameras; Contains 8. An ophthalmic apparatus according to claim 7.

16. a reflecting member disposed at a position conjugate with the iris; a photographic diaphragm disposed at a position conjugate with the iris and having an opening formed at a position eccentric from the optical axis; Including, The reflecting member reflects the illumination light from the illumination optical system and guides it to the two or more curved mirrors, and the photographic diaphragm guides the return light that has passed through the aperture to the photographic optical system.

16. An ophthalmic apparatus according to claim 15.

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