Ophthalmologic apparatus and method for operating ophthalmologic apparatus

Abstract

To provide an ophthalmologic apparatus capable of executing the examination of an eye to be examined by an examination head (a pair of concave mirrors) without bringing the examination head close to the nose of a subject, and a method for operating the ophthalmologic apparatus.SOLUTION: The fundus camera 9 includes an inspection head 20 including an illumination optical system 70 and an imaging optical system 60, a pair of concave mirrors (concave mirror unit 50) provided in the inspection head 20, and a displacement mechanism (X-axis drive unit 14, Z-axis drive unit 15, Y-axis drive unit 16, and swing rotation drive unit 17) for displacing the inspection head 20 with respect to the subject's eye E. In a case where an axis parallel to the front-rear direction which is the working distance direction (Z-axis direction) and passing through the subject's eye E is set as a reference axis VA, and an axis obtained by inclining the reference axis VA outward away from the nose N of the subject H with the subject's eye E as the center is set as a tilt axis TA, the displacement mechanism displaces the examination head 20 to an examination position of the subject's eye E along the tilt axis TA.SELECTED DRAWING: Figure 12

Description

[Technical Field]

[0001] The present invention relates to an ophthalmic apparatus having an examination head provided with a pair of concave mirrors, and a method for operating the ophthalmic apparatus. [Background technology]

[0002] In ophthalmology, ophthalmic examinations of examinee's eyes (such as obtaining various eye characteristics of the examinee's eye, such as ocular refractive power, intraocular pressure, and the number of corneal endothelial cells, as well as fundus photography and tomographic imaging) are performed using ophthalmic devices. One type of such ophthalmic device is a mirror-type fundus camera capable of wide-angle photography of the fundus (see Patent Document 1). A pair of concave mirrors is provided on the front surface of the examination head of this fundus camera. Between the examination head and the examinee's eye, these pair of concave mirrors form an optical path for illumination light irradiated from the examination head onto the examinee's eye and an optical path for return light entering the examination head from the examinee's eye.

[0003] When photographing a fundus using the fundus camera described in Patent Document 1, positioning of the examination head relative to the subject's eye, i.e., alignment, is extremely important from the viewpoint of the image quality of the fundus image. Therefore, as described in Patent Documents 2 and 3, the anterior segment of the subject's eye is photographed using a stereo camera, and alignment detection is performed to detect the relative position of the subject's eye relative to the examination head based on the anterior segment image obtained by photographing. Then, based on the result of this alignment detection, the examination head is moved by an electric actuator, thereby performing automatic alignment of the examination head relative to the subject's eye. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2023-122620 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-248376 [Patent Document 3] Patent Publication No. 2021-069415 Summary of the Invention [Problem to be solved by the invention]

[0005] When performing auto-alignment of the examination head with respect to the subject's eye using the methods described in Patent Document 2 and Patent Document 3 in the fundus camera described in Patent Document 1, it is necessary to bring the examination head, particularly the pair of concave mirrors, close to the subject's face, but at this time there is a risk that the pair of concave mirrors may come close to the subject's nose.

[0006] The present invention has been made in consideration of the above circumstances, and aims to provide an ophthalmic device and an operating method for an ophthalmic device that can perform an examination of a subject's eye using an examination head (a pair of concave mirrors) without bringing the examination head close to the subject's nose. [Means for solving the problem]

[0007] An ophthalmic device for achieving the object of the present invention comprises an examination head having an illumination optical system that emits illumination light to illuminate the test eye and an imaging optical system that guides return light from the test eye illuminated by the illumination light to an imaging element, a pair of concave mirrors provided in the examination head that form an optical path for the illumination light and return light between the examination head and the test eye, and a displacement mechanism that displaces the examination head relative to the test eye, where an axis that is parallel to the front-to-back direction that is the working distance direction of the examination head and passes through the test eye is taken as the reference axis, and an axis that is tilted outward away from the test eye with the test eye at the center is taken as the tilt axis, and the displacement mechanism displaces the examination head along the tilt axis to an examination position for the test eye.

[0008] According to this ophthalmologic apparatus, the examination head (a pair of concave mirrors) can be displaced to the examination position of the subject's eye without being brought close to the subject's nose.

[0009] In an ophthalmologic apparatus according to another aspect of the present invention, the displacement mechanism displaces the examination head to the examination position while maintaining a constant tilt angle of the tilt axis relative to the reference axis, thereby enabling the examination head (pair of concave mirrors) to be displaced to the examination position for the subject's eye without bringing the examination head close to the subject's nose.

[0010] In an ophthalmologic apparatus according to another aspect of the present invention, the displacement mechanism includes a movement mechanism that moves the examination head in the front-to-back, left-to-right, and up-to-down directions relative to the subject's eye, and a rotation mechanism that rotates the examination head about a predetermined rotation axis, thereby allowing the examination head to be arbitrarily displaced relative to the subject's eye.

[0011] In the ophthalmologic apparatus according to another aspect of the present invention, the rotation axis is parallel to the up-down direction, and the outward direction is parallel to the left-right direction.

[0012] In the ophthalmologic apparatus according to another aspect of the present invention, the rotation axis is perpendicular to the up-down direction, and the outward direction is the upper side in the up-down direction.

[0013] In an ophthalmologic apparatus according to another aspect of the present invention, the rotation shaft is provided below the examination head, and the movement mechanism moves the examination head and the rotation shaft together in the front-rear, left-right, and up-down directions.

[0014] In another aspect of the present invention, an ophthalmologic apparatus includes an ophthalmologic apparatus having a rotation axis parallel to the up-down direction and an outward direction parallel to the left-right direction, an examination head at an initial position located at the center of a range of left-right movement by the movement mechanism, and a central axis of the examination head at the initial position located at the center when viewed from one side in the up-down direction, the central axis of the examination head being parallel to the front-rear direction and located at the center when viewed from one side in the up-down direction, and a drive control unit for controlling driving of the displacement mechanism, the drive control unit performing a first drive process of driving the movement mechanism to move the examination head outward from the initial position to the tilt axis, a second drive process of driving the rotation mechanism to rotate the examination head around the rotation axis to make the central axis parallel to the tilt axis, and a third drive process of driving the movement mechanism after completion of the first and second drive processes to move the examination head along the tilt axis to an examination position, thereby enabling the examination head (a pair of concave mirrors) to be displaced to the examination position for the subject's eye without being brought close to the subject's nose.

[0015] In another aspect of the present invention, an ophthalmologic apparatus has a rotation axis parallel to the up-down direction and an outward direction parallel to the left-right direction, an examination head at an initial position located at the center of a range of left-right movement by the movement mechanism, and when the examination head is at the initial position, a central axis of the examination head is parallel to the front-rear direction and located at the center when viewed from one side in the up-down direction, and includes a drive control unit that controls driving of the displacement mechanism, and the drive control unit executes a first drive process in which the movement mechanism drives the examination head to move forward in the front-rear direction from the initial position toward the subject's eye, and then moves the examination head outward to the tilt axis, a second drive process in which the rotation mechanism drives the examination head to rotate about the rotation axis so that the central axis is parallel to the tilt axis, and a third drive process in which the movement mechanism is driven after the first and second drive processes are completed to move the examination head along the tilt axis to the examination position. This allows the examination head (a pair of concave mirrors) to be displaced to the examination position for the subject's eye without bringing it close to the subject's nose, and further reduces the amount of outward movement of the examination head in the first drive process.

[0016] In another aspect of the present invention, an ophthalmologic apparatus has a rotation axis parallel to the up-down direction and an outward direction parallel to the left-right direction, an examination head at an initial position located at the center of a range of left-right movement by the movement mechanism, and when the examination head is at the initial position, a central axis of the examination head is parallel to the front-back direction and located at the center when viewed from one side in the up-down direction, and includes a drive control unit that controls driving of the displacement mechanism, and the drive control unit drives the movement mechanism and the rotation mechanism to simultaneously move the examination head forward in the front-back direction toward the subject's eye, move the examination head outward, and rotate the examination head around the rotation axis, thereby performing a first drive process to move the examination head to the tilt axis and make the central axis parallel to the tilt axis, and a second drive process to drive the movement mechanism after completion of the first drive process to move the examination head along the tilt axis to the examination position. This allows the examination head (a pair of concave mirrors) to be displaced to the examination position for the subject's eye without bringing it close to the subject's nose, and further allows the examination head to be displaced to the examination position in the shortest time.

[0017] In another aspect of the present invention, an ophthalmologic apparatus has a rotation axis that is perpendicular to the up-down direction and an outward direction that is upward in the up-down direction, an examination head that is at the center of a range of left-right movement by the movement mechanism when in an initial position, and a central axis of the examination head that is parallel to the front-rear direction and is at the center when viewed from one side in the up-down direction when the examination head is at the initial position, and includes a drive control unit that controls driving of the displacement mechanism, and the drive control unit executes a first drive process in which the movement mechanism and the rotation mechanism are driven to move the examination head to the tilt axis and make the central axis parallel to the tilt axis, and a second drive process in which the movement mechanism is driven after completion of the first drive process to move the examination head along the tilt axis to the examination position, thereby making it possible to displace the examination head (a pair of concave mirrors) to the examination position for the subject's eye without bringing it close to the subject's nose.

[0018] In another aspect of the ophthalmic device of the present invention, the rotation axis is located forward in the front-to-back direction, closer to the subject's eye than the examination head, and a moving mechanism moves the examination head and the rotation axis together in the front-to-back, left-to-right, and up-to-down directions.

[0019] In another aspect of the present invention, an ophthalmologic apparatus has a rotation axis parallel to the up-down direction and an outward direction parallel to the left-right direction, an examination head at an initial position located at the center of a range of left-right movement by the movement mechanism, and a central axis of the examination head at the initial position located at the center when viewed from one side in the up-down direction, the central axis of the examination head being parallel to the front-rear direction and located at the center when viewed from one side in the up-down direction, and a drive control unit for controlling driving of the displacement mechanism, the drive control unit executes a first drive process in which the movement mechanism is driven to move the examination head to a position where the rotation axis coincides with the subject's eye when viewed from the one side, a second drive process in which, after completion of the first drive process, the rotation mechanism is driven to rotate the examination head around the rotation axis to move the examination head to the tilt axis and make the central axis parallel to the tilt axis, and a third drive process in which, after completion of the second drive process, the movement mechanism is driven to move the examination head along the tilt axis to the examination position, thereby allowing the examination head (a pair of concave mirrors) to be displaced to the examination position for the subject's eye without being brought close to the subject's nose.

[0020] In another aspect of the present invention, an ophthalmologic apparatus has a rotation axis parallel to the up-down direction and an outward direction parallel to the left-right direction, an examination head at an initial position located at the center of a range of left-right movement by the movement mechanism, and a central axis of the examination head at the initial position located at the center when viewed from one side in the up-down direction, the central axis of the examination head being parallel to the front-rear direction and located at the center when viewed from one side in the up-down direction, and a drive control unit for controlling driving of the displacement mechanism, the drive control unit simultaneously performs a process of driving the movement mechanism to move the examination head to a position where the rotation axis coincides with the subject's eye when viewed from one side, and a process of driving the rotation mechanism to rotate the examination head around the rotation axis, thereby performing a first drive process of moving the examination head to the tilt axis and making the central axis parallel to the tilt axis, and a second drive process of driving the movement mechanism after completion of the first drive process to move the examination head along the tilt axis to the examination position, whereby the examination head (a pair of concave mirrors) can be displaced to the examination position for the subject's eye without being brought close to the subject's nose, and further, the examination head can be displaced to the examination position in the shortest time.

[0021] In another aspect of the ophthalmologic device of the present invention, the rotation mechanism is capable of rotating the examination head around a first rotation axis that is parallel to the vertical direction and a second rotation axis that is perpendicular to the vertical direction.

[0022] In an ophthalmologic apparatus according to another aspect of the present invention, the examination head is located at the center of a range of left-right movement by the moving mechanism when in an initial position, and when the examination head is located at the initial position, the central axis of the examination head is parallel to the front-rear direction and located at the center when viewed from one side in the up-down direction, and the apparatus includes a drive control unit that controls driving of the displacement mechanism, and the drive control unit executes a process of driving the moving mechanism to move the examination head to a position where the first rotation axis and the second rotation axis coincide with the subject's eye, and a process of driving the rotation mechanism to rotate the examination head about at least one of the first rotation axis and the second rotation axis, thereby executing a first drive process of moving the examination head to the tilt axis and making the central axis parallel to the tilt axis, and a second drive process of driving the moving mechanism after completion of the first drive process to move the examination head along the tilt axis to the examination position, thereby making it possible to displace the examination head (a pair of concave mirrors) to the examination position for the subject's eye without bringing the examination head (a pair of concave mirrors) close to the subject's nose.

[0023] An ophthalmologic apparatus according to another aspect of the present invention includes a fixation light projection system that projects fixation light onto the subject's eye, thereby allowing the line of sight of the subject's eye to follow the displacement of the examination head.

[0024] An ophthalmologic apparatus according to another aspect of the present invention includes an imaging unit provided in the examination head for capturing an image of the anterior segment of the subject's eye while the examination head is being displaced by a displacement mechanism, an alignment detection unit for detecting the relative position of the subject's eye with respect to the examination head based on the image of the anterior segment of the subject's eye captured by the imaging unit, and a drive control unit for controlling the driving of the displacement mechanism, wherein the drive control unit drives the displacement mechanism based on the detection result of the alignment detection unit to move the examination head along the tilt axis to the examination position, thereby making it possible to displace the examination head (a pair of concave mirrors) to the examination position of the subject's eye without bringing it close to the subject's nose.

[0025] In another aspect of the present invention, an ophthalmologic apparatus includes an operation unit, and a drive control unit that is switchable to a manual control mode in which the displacement mechanism is driven to displace the examination head in response to an input operation on the operation unit, and the drive control unit switches to the manual control mode if the alignment detection unit does not detect the relative position while the displacement mechanism is moving the examination head for a predetermined period of time or a predetermined distance. This allows the apparatus to automatically switch to the manual control mode when the alignment detection unit cannot detect the relative position due to, for example, individual facial differences, pathological eyes, eyelids such as ptosis, or the influence of eyelashes.

[0026] In an ophthalmologic apparatus according to another aspect of the present invention, the pair of concave mirrors are a first concave mirror and a second concave mirror connected by a concave mirror bracket, the first concave mirror having a first reflecting surface facing the eye to be examined, the second concave mirror having a second reflecting surface partially facing the first reflecting surface and reflecting illumination light from the illumination optical system to the first reflecting surface and reflecting return light from the first reflecting surface to the imaging optical system, and the apparatus is equipped with a switching mechanism that can switch the pair of concave mirrors between a first position where the first reflecting surface is located in front of the left eye and the second reflecting surface is located on the left side of the face when the eye to be examined is the left eye, and a second position where the first reflecting surface is located in front of the right eye and the second reflecting surface is located on the right side of the face when the eye to be examined is the right eye, thereby enabling wide-angle imaging of the area to be observed in the eye to be examined.

[0027] To achieve the object of the present invention, an operating method of an ophthalmologic apparatus includes an examination head having an illumination optical system that emits illumination light to illuminate the subject's eye and an imaging optical system that guides return light from the subject's eye illuminated by the illumination light to an imaging element, a pair of concave mirrors that are provided in the examination head and form optical paths for the illumination light and return light between the examination head and the subject's eye, and a displacement mechanism that displaces the examination head relative to the subject's eye, in which an axis that is parallel to the front-to-back direction that is the working distance direction of the examination head and that passes through the subject's eye is taken as the reference axis, and an axis that is tilted outward from the reference axis, away from the subject's nose, with the subject's eye as the center is taken as the inclination axis, and the displacement mechanism is driven to displace the examination head along the inclination axis to an examination position for the subject's eye. [Effects of the Invention]

[0028] The present invention makes it possible to perform an examination of the subject's eye using the examination head (a pair of concave mirrors) without bringing the examination head close to the subject's nose. [Brief explanation of the drawings]

[0029] [Figure 1] 1 is a perspective view of the appearance of a fundus camera according to a first embodiment. [Figure 2] FIG. 1 is a side view of a fundus camera according to a first embodiment. [Figure 3] FIG. 1 is a front view of a fundus camera according to a first embodiment, as viewed from the subject side. [Figure 4] FIG. 10 is a top view of the concave mirror unit rotated to a first position when photographing the fundus of the left eye. [Figure 5] FIG. 10 is a top view of the concave mirror unit rotated to a second position when photographing the fundus of the right eye. [Figure 6] FIG. 2 is a top view of the imaging optical system of the inspection head. [Figure 7] FIG. 2 is a side view of the illumination optical system of the inspection head. [Figure 8] FIG. 2 is a front view of the illumination optical system and alignment optical system of the inspection head. [Figure 9] FIG. 2 is a perspective view of the face support section as seen from the subject side. [Figure 10] FIG. 2 is a functional block diagram of a control device. [Figure 11] FIG. 10 is an explanatory diagram for explaining a method of auto-alignment of the inspection head. [Figure 12] FIG. 10 is an explanatory diagram for explaining Example 1-1 of auto-alignment of the inspection head in the first embodiment. [Figure 13] FIG. 10 is an explanatory diagram for explaining a first and second example of automatic alignment of the inspection head in the first embodiment. [Figure 14] 10A and 10B are explanatory diagrams for explaining a first to third example of automatic alignment of the inspection head in the first embodiment. [Figure 15]4 is a flowchart showing a flow of processing for photographing the fundus of the subject's eye by the fundus camera of the first embodiment. [Figure 16] 10 is a flowchart showing the flow of an auto-alignment process for the inspection head. [Figure 17] 10A and 10B are explanatory diagrams for explaining displacement of the inspection head after the start of auto-alignment. [Figure 18] 10 is a flowchart showing a flow of a modified example of auto-alignment of the inspection head. [Figure 19] FIG. 10 is a side view of the main part of the fundus camera according to the second embodiment. [Figure 20] FIG. 10 is an explanatory diagram for explaining Example 2-1 of auto-alignment of the inspection head in the second embodiment. [Figure 21] FIG. 10 is an explanatory diagram for explaining Example 2-2 of auto-alignment of the inspection head in the second embodiment. [Figure 22] FIG. 10 is a side view of the main part of the fundus camera according to the third embodiment. [Figure 23] FIG. 10 is an explanatory diagram for explaining a third example of automatic alignment of the inspection head in the third embodiment. [Figure 24] FIG. 13 is an explanatory diagram for explaining a fourth example of automatic alignment of the inspection head in the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0030] [First embodiment] <Overall configuration of fundus camera> Fig. 1 is an external perspective view of a fundus camera 9 according to the first embodiment. Fig. 2 is a side view of the fundus camera 9 according to the first embodiment. Fig. 3 is a front view of the fundus camera 9 according to the first embodiment as viewed from the side of a subject H. In the drawings, the X-axis direction is the left-right direction based on the subject H, the Y-axis direction is the up-down direction, and the Z-axis direction is the front-to-back direction (also referred to as the working distance direction) parallel to the front direction approaching the subject H (the subject's eye E) and the rear direction moving away from the subject H.

[0031] As shown in Figures 1 to 3, the fundus camera 9 corresponds to the ophthalmic device of the present invention, and includes an apparatus stand 10, an examination head 20 (also called an optical head), a face support unit 30, a control panel 40, a concave mirror unit 50, a photographing optical system 60, an illumination optical system 70, an alignment optical system 80, and a control device 90.

[0032] The device pedestal 10 is a base member placed on an optical table T whose height in the Y-axis direction is adjustable. A face support unit 30 is fixed to the front end of the device pedestal 10 on the front side in the Z-axis direction (toward the subject H), and a control panel 40 is attached to the rear end of the device pedestal 10 on the rear side in the Z-axis direction (toward the examiner). In addition, an examination head 20 is disposed in the central region of the device pedestal 10 between the face support unit 30 and the control panel 40.

[0033] An X-axis movable frame 11 is disposed in a central region of the device pedestal 10, and is movable in the X-axis direction relative to the device pedestal 10. A Z-axis movable frame 12 is disposed on the X-axis movable frame 11, and is movable in the Z-axis direction relative to the X-axis movable frame 11. A Y-axis movable frame 13 is disposed on the Z-axis movable frame 12, and is movable in the Y-axis direction relative to the Z-axis movable frame 12. The device pedestal 10 has an X-axis driver 14 that moves the X-axis movable frame 11 in the X-axis direction. The X-axis movable frame 11 has a Z-axis driver 15 that moves the Z-axis movable frame 12 in the Z-axis direction. The Z-axis movable frame 12 has a Y-axis driver 16 that moves the Y-axis movable frame 13 in the Y-axis direction. The X-axis driver 14, the Z-axis driver 15, and the Y-axis driver 16 constitute a movement mechanism of the present invention, and may be, for example, a motor actuator.

[0034] The inspection head 20 is provided with a concave mirror unit 50, a photographing optical system 60, an illumination optical system 70, and an alignment optical system 80. The inspection head 20 is provided on a Y-axis movable frame 13. This allows the inspection head 20 to move in the X, Y, and Z-axis directions relative to the device stand 10 via the X-axis movable frame 11, the Z-axis movable frame 12, and the Y-axis movable frame 13.

[0035] The Y-axis movable frame 13 is provided with a swing rotation drive unit 17 and a rotation shaft 21. The swing rotation drive unit 17, together with the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16, constitute the displacement mechanism of the present invention.

[0036] The swing rotation drive unit 17 rotates (swings) the inspection head 20 around a rotation axis 21 parallel to the Y-axis direction. This swing rotation drive unit 17 is composed of, for example, a motor, a worm gear, and a motor drive circuit. The rotation axis 21 is provided below the inspection head 20 in the Y-axis direction, and moves integrally with the inspection head 20 in the X-, Y-, and Z-axis directions and rotates integrally with the inspection head 20.

[0037] In this way, the inspection head 20 can be moved in the X, Y, and Z-axis directions by the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16, and can also be rotated around the rotation axis 21 by the swing rotation drive unit 17. This allows the inspection head 20 to be moved linearly in each axis direction, rotated around the rotation axis 21, or moved so as to trace a trajectory that combines linear and rotational movements during auto-alignment of the inspection head 20 and when switching between the left and right eyes.

[0038] The face support unit 30 is provided at the front end of the device stand 10, and is located further forward in the Z-axis direction than the concave mirror unit 50. The face support unit 30 supports the forehead and chin of the subject H so as to stabilize the position and orientation of the subject's eye E. The face support unit 30 has a main body 31, a forehead support frame 32 against which the forehead of the subject H contacts, a chin rest 33 against which the chin of the subject H contacts, a lifting rod 34 parallel to the Y-axis direction, and a chin rest drive unit 35.

[0039] The chin rest driver 35 is built into the main body 31 and drives the lifting rod 34 in the Y-axis direction. The chin rest driver 35 is configured with, for example, a motor and a motor drive circuit. A chin rest 33 is provided at the upper end of the lifting rod 34, and the position of the chin rest 33 in the Y-axis direction can be adjusted by driving the lifting rod 34 in the Y-axis direction by the chin rest driver 35.

[0040] The control panel 40 is provided at the rear end of the device stand 10. The control panel 40 has a touch panel screen 41 that displays in color a fundus image of the subject's eye E photographed by the photographing optical system 60 and an anterior eye image of the subject's eye E photographed by the alignment optical system 80 (stereo cameras 81L, 81R shown in FIG. 8, which will be described later).

[0041] The touch panel screen 41 accepts input of touch operations by the examiner on various images displayed on the screen (such as operation button images, anterior eye images, and fundus images), and outputs operation signals to the control device 90. Therefore, the control panel 40 (touch panel screen 41) functions as the operation unit of the present invention. A known tablet terminal may be used instead of the control panel 40. Also, various known operation units and display units other than the control panel 40 may be used.

[0042] The control panel 40 is used to adjust the position of the chin rest 33, move the examination head 20 in the XYZ axis directions, rotate the examination head 20, switch between auto-alignment and manual alignment, start the examination, and save the examination results (fundus images).

[0043] The concave mirror unit 50 is composed of a first concave mirror 51 and a second concave mirror 52, which correspond to a pair of concave mirrors of the present invention, and a concave mirror bracket 53 that connects the first concave mirror 51 and the second concave mirror 52. The concave mirror unit 50 is rotatably held at a position on the front side of the examination head 20 by a unit rotation drive unit 55 provided on the examination head 20, and faces the face support unit 30 (the face of the subject H).

[0044] The unit rotation drive unit 55 corresponds to the switching mechanism of the present invention and rotates the concave mirror unit 50 (concave mirror bracket 53) around a unit rotation axis 54 parallel to the Z-axis direction. The unit rotation drive unit 55 has, for example, a motor, a timing belt stretched over two pulleys, and a motor drive circuit. When the subject's eye E is the left eye, the concave mirror unit 50 is switched by the unit rotation drive unit 55 to a first position (see FIG. 4) described below, and when the subject's eye E is the right eye, the concave mirror unit 50 is switched by the unit rotation drive unit 55 to a second position (see FIG. 5) described below.

[0045] The imaging optical system 60 is provided on the upper surface side of the inspection head 20. The illumination optical system 70 is provided on the lower surface side of the inspection head 20. The alignment optical systems 80 are provided on the left and right positions on the lower surface side of the front end of the inspection head 20, respectively.

[0046] The control device 90 controls each part of the fundus camera 9 (such as the face support unit 30, the concave mirror unit 50, the photographing optical system 60, the illumination optical system 70, and the alignment optical system 80) based on input operations including touch operations on the control panel 40 (touch panel screen 41). The control device 90 is provided in the inspection head 20, and has, for example, a main board, a TRC (Time Ratio Control) control board, and a galvano driver board as its hardware configuration.

[0047] <Detailed configuration of the concave mirror unit> Fig. 4 is a top view of the concave mirror unit 50 rotated to a first position when photographing the fundus of the left eye. Fig. 5 is a top view of the concave mirror unit 50 rotated to a second position when photographing the fundus of the right eye. Note that the symbol CL in the figure indicates the central axis of the examination head 20. This central axis CL coincides (or roughly coincides, the same applies hereinafter) with the unit rotation axis 54 when the examination head 20 is viewed from one side in the Y-axis direction.

[0048] 4 and 5, the concave mirror unit 50 is rotatably held by a unit rotation drive unit 55 at a position between the subject's eye E and the front surface of the examination head 20 (dichroic mirrors 57L, 57R shown in FIG. 6 described later). The first concave mirror 51 and the second concave mirror 52 constituting the concave mirror unit 50 form a reflected optical path of illumination light from the illumination optical system 70 to the fundus of the subject's eye E, and a reflected optical path of return light from the fundus of the subject's eye E to the photographing optical system 60.

[0049] A first reflecting surface 51a having two optically conjugate focal points F1 and F2 is formed on the first concave mirror 51. The position of the focal point F1 is set to the position where the pupil of the subject's eye E is positioned when observing and photographing the fundus of the subject's eye E.

[0050] The second concave mirror 52 is formed with a second reflecting surface 52a having two optically conjugate focal points F3 and F4. This second reflecting surface 52a partially faces the first reflecting surface 51a. The position of the focal point F3 coincides with the position of the focal point F2. The position of the focal point F4 is the position where the optical paths of the imaging optical system 60 and the illumination optical system 70 branch off.

[0051] The concave mirror bracket 53 connects the first concave mirror 51 and the second concave mirror 52 while maintaining the positional relationship between the focal points F1 to F4. A unit rotation shaft 54 ​​of a unit rotation drive unit 55 is connected to the concave mirror bracket 53.

[0052] The concave mirror unit 50 is rotatable (pivotable) to a first position (see FIG. 4) when the subject's eye E is the left eye, and to a second position (see FIG. 5) when the subject's eye E is the right eye. By rotating the concave mirror unit 50 using a unit rotation drive section 55, the concave mirror unit 50 can be used for both the left and right eyes.

[0053] The "first position" is a horizontal arrangement state in which the first concave mirror 51 is placed in front of the left eye and the second concave mirror 52 is placed on the left side of the face, as shown in Fig. 4. The "second position" is a horizontal arrangement state in which the first concave mirror 51 is placed in front of the right eye and the second concave mirror 52 is placed on the right side of the face, as shown in Fig. 5. The concave mirror unit 50 has a reference position in addition to the first and second positions, and this "reference position" is a vertical arrangement state in which the first concave mirror 51 is placed at a lower position and the second concave mirror 52 is placed at an upper position in the Y-axis direction, as shown in Fig. 2 described above.

[0054] When photographing the fundus of the left eye, the examination head 20 is positioned closer to the left end of the device pedestal 10 as viewed from the subject H, with the central axis CL tilted at an angle relative to the Z-axis direction, as shown in Fig. 4. When photographing the fundus of the right eye, the examination head 20 is positioned closer to the right end of the device pedestal 10 as viewed from the subject H, with the central axis CL tilted at an angle relative to the Z-axis direction, as shown in Fig. 5.

[0055] Furthermore, before fundus photography begins, the examination head 20 is placed at an initial position, which is the center position of the device stand 10 in the X-axis direction (the center position of the movable range of the examination head 20 in the X-axis direction), and is a retracted position retracted (away) from the subject H in the Z-axis direction backward (see symbol XIIA in FIG. 12 ).

[0056] Fig. 6 is a top view of the imaging optical system 60 of the inspection head 20. Fig. 7 is a side view of the illumination optical system 70 of the inspection head 20. Fig. 8 is a front view of the illumination optical system 70 and alignment optical system 80 of the inspection head 20.

[0057] 6 to 8, the photographing optical system 60 has a left eye photographing optical system 60L that photographs the fundus of the left eye, and a right eye photographing optical system 60R that photographs the fundus of the right eye (see FIG. 6). The illumination optical system 70 is provided independently along the central axis CL of the inspection head 20 (see FIG. 7). The alignment optical system 80 has a left eye alignment optical system 80L that is used for auto-alignment before photographing the fundus of the left eye, and a right eye alignment optical system 80R that is used for auto-alignment before photographing the fundus of the right eye (see FIG. 8).

[0058] The photographing optical system 60 and the illumination optical system 70 employ a separate illumination system in which the observation light beam and the illumination light beam are offset within the pupil circle of the subject's eye E. Furthermore, dichroic mirrors 57L, 57R that merge the observation light path, the illumination light path, and the alignment light path are disposed at the optical path branching section of each optical system. Note that if a coaxial illumination system in which the observation light beam and the illumination light beam are aligned within the pupil circle as described above is employed instead of the separate illumination system, a perforated mirror may be disposed at the optical path branching section.

[0059] 6, the photographing optical system 60 captures an image of return light from the fundus of the subject's eye E, which enters through the concave mirror unit 50. The photographing optical system 60 includes a left-eye photographing optical system 60L and a right-eye photographing optical system 60R, a slide plate 68, and a focusing drive unit 69.

[0060] The left eye imaging optical system 60L and the right eye imaging optical system 60R have an axisymmetric structure with respect to the central axis CL on the upper surface of the inspection head 20. Furthermore, the left eye imaging optical system 60L and the right eye imaging optical system 60R are decentered optical systems with decentered optical paths.

[0061] The left-eye photographing optical system 60L includes a dichroic mirror 57L, a photographing aperture 600L, a first reflecting mirror 61L, a first lens unit 62L, a second reflecting mirror 63L, a second lens unit 64L, a focusing lens 65L, a third lens unit 66L, and an imaging unit 67L, which are arranged along the optical path of the returned light indicated by the arrow in the figure. The photographing aperture 600L is arranged at a position conjugate with the pupil of the subject's eye E. In the imaging unit 67L, a fundus image sensor 671L (corresponding to an imaging element of the present invention) is arranged at an inclination angle that opens outward in a plan view due to the setting of the decentered optical system. The fundus image sensor 671L is arranged at a position conjugate with the fundus of the subject's eye E.

[0062] The right-eye photographing optical system 60R includes a dichroic mirror 57R, a photographing aperture 600R, a first reflecting mirror 61R, a first lens unit 62R, a second reflecting mirror 63R, a second lens unit 64R, a focusing lens 65R, a third lens unit 66R, and an imaging unit 67R, which are arranged along the optical path of the returned light indicated by the arrow in the figure. The photographing aperture 600R is arranged at a position conjugate with the pupil of the subject's eye E. In the imaging unit 67R, a fundus image sensor 671R (corresponding to an imaging element of the present invention) is arranged at an inclination angle that opens outward in a plan view due to the setting of the decentered optical system. The fundus image sensor 671R is arranged at a position conjugate with the fundus of the subject's eye E.

[0063] The slide plate 68 is provided so as to be movable in a direction along the central axis CL (the Z-axis direction in the drawing) on ​​the upper surface of the inspection head 20. On the upper surface of this slide plate 68, second lens units 64L, 64R, focusing lenses 65L, 65R, and third lens units 66L, 66R are provided.

[0064] The focusing drive unit 69 is, for example, a motor actuator, and performs focusing control to align the focus of the photographing optical system 60 with the fundus of the subject's eye E by displacing the slide plate 68 in a direction along the central axis CL when photographing the fundus of the subject's eye E.

[0065] 7 and 8, the illumination optical system 70 projects slit scanning light, which is illumination light, onto the fundus of the subject's eye E via the concave mirror unit 50. The illumination optical system 70 has a light source unit 71, a slit unit 72, a galvanometer scanner 73 (optical scanner), a first reflecting mirror 741, a second reflecting mirror 742, a left / right switching mirror 75, and dichroic mirrors 57L and 57R, which are arranged along the illumination light path shown in the figures.

[0066] The optical path from the left-right switching mirror 75 to the dichroic mirror 57L has a first lens unit 761L, a third reflecting mirror 763L, and a second lens unit 762L shown in Fig. 8, and a fourth reflecting mirror 744L shown in Fig. 7. Moreover, the optical path from the left-right switching mirror 75 to the dichroic mirror 57R has a first lens unit 761R, a third reflecting mirror 763R, and a second lens unit 762R shown in Fig. 8, and a fourth reflecting mirror 744R shown in Fig. 7.

[0067] The light source section 71 emits illumination light toward the slit unit 72. The light source section 71 has an iris diaphragm 71a in the vicinity of the slit unit 72. The iris diaphragm 71a is disposed at a position conjugate with the pupil of the eye E to be examined.

[0068] The slit unit 72 has a slit 72a and a projection lens 72b. The slit 72a is disposed at a position conjugate with the fundus of the subject's eye E. As a result, slit-shaped illumination light (slit light) is irradiated onto the fundus of the subject's eye E. The slit unit 72 is also provided with a slit driver 77. The slit driver 77 has a linear motion part and adjusts the focus of the slit 72a to match the subject's eye E.

[0069] The galvano scanner 73 scans the illumination light (slit light) that is irradiated onto the fundus of the subject's eye E. The scanner driving unit 78 controls the driving of the galvano scanner 73 (the scanning angle of the slit light).

[0070] The left-right switching mirror 75 is provided below the unit rotation axis 54 in the Y-axis direction, and is provided rotatable about a mirror rotation axis 75a (see FIG. 8) that is parallel to the Z-axis direction. A mirror rotation drive unit 79 is connected to the mirror rotation axis 75a. By rotating the mirror rotation axis 75a, the mirror rotation drive unit 79 can switch the tilt angle of the left-right switching mirror 75 between a first angle that reflects illumination light toward the first lens unit 761L and a second angle that reflects illumination light toward the first lens unit 761R.

[0071] The illumination optical system 70 may be provided with a fixation light projection system 770 (see FIG. 10) that projects fixation light onto the fundus of the eye E to fixate the eye E.

[0072] As shown in Fig. 8, the alignment optical systems 80 are provided at left and right positions at the front end of the examination head 20. The alignment optical systems 80 acquire an image of the anterior segment of the subject's eye E when performing auto-alignment to adjust the position of the subject's eye E to the position of the first focal point F1 of the first concave mirror 51. The alignment optical systems 80 include a left-eye alignment optical system 80L used for auto-alignment of the left eye, and a right-eye alignment optical system 80R used for auto-alignment of the right eye. The left-eye alignment optical system 80L and the right-eye alignment optical system 80R (stereo cameras 81L, 81R) function as the imaging unit of the present invention.

[0073] An alignment optical frame 22L is fixed to the inspection head 20 below the dichroic mirror 57L in the Y-axis direction, and this alignment optical frame 22L is provided with an alignment optical system 80L for the left eye. The alignment optical system 80L for the left eye has a stereo camera 81L and an alignment illumination lamp 82L arranged below the dichroic mirror 57L in the Y-axis direction. The alignment illumination lamp 82L irradiates illumination light onto the left eye, which is the eye E to be examined, via the dichroic mirror 57L. The stereo camera 81L has an anterior eye image sensor, and takes stereo images of the left eye irradiated with illumination light via the dichroic mirror 57L and outputs an anterior eye image of the left eye.

[0074] An alignment optical frame 22R is fixed to the inspection head 20 below the dichroic mirror 57R in the Y-axis direction, and this alignment optical frame 22R is provided with an alignment optical system 80R for the right eye. The alignment optical system 80R for the right eye has a stereo camera 81R and an alignment illumination lamp 82R, which are arranged below the dichroic mirror 57R in the Y-axis direction. The alignment illumination lamp 82R irradiates illumination light onto the right eye, which is the eye E to be examined, via the dichroic mirror 57R. The stereo camera 81R has an anterior eye image sensor, and takes stereoscopic images of the right eye irradiated with illumination light via the dichroic mirror 57R, and outputs an anterior eye image of the right eye.

[0075] <Detailed configuration of face support section> Fig. 9 is a perspective view of the face support unit 30 as seen from the side of the subject H. As shown in Fig. 9, the face support unit 30 supports the face of the subject H in different positions and postures when photographing the fundus of the left eye and when photographing the fundus of the right eye (see Figs. 4 and 5).

[0076] The forehead support frame 32 has a left-eye forehead support surface 32a against which the forehead of the subject H abuts when photographing the fundus of the left eye, and a right-eye forehead support surface 32b against which the forehead of the subject H abuts when photographing the fundus of the right eye. The left-eye forehead support surface 32a and the right-eye forehead support surface 32b are made of silicone rubber or the like.

[0077] The chin rest 33 has a left-eye chin rest surface 33a that supports the chin of the subject H when photographing the fundus of the left eye, and a right-eye chin rest surface 33b that supports the chin of the subject H when photographing the fundus of the right eye. The left-eye chin rest surface 33a and the right-eye chin rest surface 33b each have a concave curved shape corresponding to the shape of the chin, and are formed on the chin rest 33 so that they partially overlap each other.

[0078] <Detailed configuration of the control device> Fig. 10 is a functional block diagram of the control device 90. As shown in Fig. 10, in addition to the components of the fundus camera 9 described above, the control device 90 is connected to an image forming unit 120, a data processing unit 130, and a storage unit 131.

[0079] The image forming unit 120 forms a fundus image of the subject's eye E based on the imaging signals output from the fundus image sensors 671L and 671R. The data processing unit 130 performs various image processing such as brightness correction processing on the fundus image of the subject's eye E formed by the image forming unit 120.

[0080] The storage unit 131 is a recording medium (storage medium) that stores a program executed by the control device 90, and various known storages are used. The storage unit 131 also stores a fundus image of the subject's eye E and the like.

[0081] The control device 90 includes an arithmetic circuit configured with various processors, memories, etc. The various processors include a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), and a programmable logic device (e.g., simple programmable logic device (SPLD), complex programmable logic device (CPLD), and field programmable gate array (FPGA)). The various functions of the control device 90 may be realized by a single processor, or by multiple processors of the same or different types.

[0082] The control device 90 functions as an inclination angle determination unit 91, an alignment detection unit 92, a drive control unit 93, a fixation control unit 94, a fundus photography control unit 95, and a storage control unit 96 by executing a control program stored in the memory unit 131.

[0083] Since each component of the control device 90 functions during auto-alignment of the inspection head 20, a method for auto-aligning the inspection head 20 will first be described with reference to Fig. 11. Note that the symbol "OS" in Fig. 11 indicates the left eye (Oculus Sinister), and the symbol "OD" indicates the right eye (Oculus Dexter). As indicated by the symbol XIA in Fig. 11, when auto-aligning the inspection head 20, if the inspection head 20 is moved forward in the Z-axis direction from a position directly in front of the subject's eye E (here, the left eye OS), there is a risk that the inspection head 20 (first concave mirror 51) will come close to the nose N of the subject H.

[0084] Therefore, as shown by symbol XIB in Figure 11, in the fundus camera 9 of this embodiment, during auto-alignment of the examination head 20, the examination head 20 is approached from an oblique direction to the subject eye E when viewed from one side in the Y-axis direction (for example, from the upper side in the Y-axis direction).

[0085] Specifically, an axis parallel to the Z-axis direction and passing through the subject's eye E (for example, its center) is defined as the reference axis VA, a direction in the X-axis direction that is away from the nose N using the subject's eye E (here, the left eye OS) as a reference is defined as the outward direction X1, and an axis tilted by an angle θ from the reference axis VA toward the outward direction X1 with the subject's eye E as the center is defined as the tilt axis TA. Then, when viewed from above in the Y-axis direction, the examination head 20 is displaced along the tilt axis TA to an examination position (hereinafter simply referred to as the examination position) where fundus photography of the subject's eye E can be performed. The "displacement" here includes movement and rotation of the examination head 20 in the X, Y, and Z axes.

[0086] 10 , the tilt angle determination unit 91 determines the tilt angle θ of the tilt axis TA relative to the reference axis VA in the XZ plane. For example, the tilt angle determination unit 91 determines a value selected by the examiner on the control panel 40 from among a plurality of angles (10°, 15°, 20°, etc.) as the tilt angle θ, and outputs information about this tilt angle θ to the drive control unit 93.

[0087] The tilt angle determination unit 91 may detect the relative position of the nose N with respect to the inspection head 20 based on a captured image obtained by stereo-photographing the nose N with one of the stereo cameras 81L, 81R, and determine, based on this detection result, the tilt angle θ that can prevent the inspection head 20 (first concave mirror 51) from approaching the nose N. Here, "one of the stereo cameras 81L, 81R" refers to the stereo camera 81L when photographing the fundus of the left eye OS, and the stereo camera 81R when photographing the fundus of the right eye OD (the same applies hereinafter).

[0088] The alignment detection unit 92 detects the relative position of the subject's eye E with respect to the examination head 20 by identifying the pupil center position of the subject's eye E and calculating the three-dimensional coordinates of this pupil center position based on an anterior ocular segment image of the subject's eye E stereoscopically photographed by one of the stereo cameras 81L, 81R during auto-alignment of the examination head 20. Note that the method of alignment detection using the stereo cameras 81L, 81R is a known technique (see Patent Document 2 above), and therefore a detailed description thereof will be omitted here.

[0089] The drive control unit 93 controls the driving of each of the drive units 14 to 17, 35, 55, 69, 77 to 79 of the fundus camera 9. The drive control unit 93 then drives the X-axis drive unit 14, the Z-axis drive unit 15, the Y-axis drive unit 16, and the swing rotation drive unit 17 to align the examination head 20 with the subject's eye E and switch the subject's eye E to be examined (switch between left and right eyes). Furthermore, before the alignment of the examination head 20 is completed, the drive control unit 93 drives the unit rotation drive unit 55 to rotate the concave mirror unit 50 to the first position (when photographing the fundus of the left eye OS) or the second position (when photographing the fundus of the right eye OD).

[0090] Alignment of the inspection head 20 includes auto-alignment and manual alignment (corresponding to the manual control mode of the present invention). Auto-alignment is alignment performed by automatically driving the X-axis drive unit 14, Z-axis drive unit 15, Y-axis drive unit 16, and swing rotation drive unit 17. Manual alignment is alignment performed by driving the X-axis drive unit 14, Z-axis drive unit 15, Y-axis drive unit 16, and swing rotation drive unit 17 in response to input operations by the examiner via the control panel 40. Note that switching between auto-alignment and manual alignment is performed via the control panel 40.

[0091] During auto-alignment, the drive control unit 93 determines the tilt axis TA corresponding to the tilt angle θ based on the tilt angle θ initially determined by the tilt angle determination unit 91.

[0092] For example, the drive control unit 93 first determines the reference axis VA based on captured images obtained by stereoscopically capturing the face (eye E or nose N, etc.) of the subject H using one of the stereo cameras 81L, 81R. Alternatively, the drive control unit 93 estimates the reference axis VA based on the position of the chin rest 33 in the Y-axis direction and known information on distinguishing between the left eye OS and the right eye OD. Then, the drive control unit 93 determines an axis obtained by tilting the reference axis VA by an angle θ in the outward direction X1 around the eye E as the tilt axis TA.

[0093] Next, the drive control unit 93 drives the X-axis drive unit 14, the Z-axis drive unit 15, the Y-axis drive unit 16, and the swing rotation drive unit 17 to start auto-alignment, which automatically displaces the examination head 20 from the initial position at the time of power-on of the fundus camera 9 to the examination position.

[0094] Fig. 12 is an explanatory diagram for explaining a 1-1 example of auto-alignment of the inspection head 20 in the first embodiment. As indicated by reference symbol XIIA in Fig. 12, the inspection head 20 is, as described above, at its initial position, located at the center position (including an approximate center position or a position facing the face support part 30) of the movable range of the inspection head 20 in the X-axis direction, and at a retracted position retracted rearward in the Z-axis direction from the subject H. When the inspection head 20 is located at the initial position, the central axis CL of the inspection head 20 coincides with the above-mentioned central position when viewed from above in the Y-axis direction.

[0095] First, the drive control unit 93 drives the X-axis drive unit 14 to execute a first drive process to move the inspection head 20 in the outward direction X1 from the initial position to the tilt axis TA when viewed from above in the Y-axis direction.

[0096] As indicated by reference symbol XIIB in Fig. 12, after completing the first driving process, the drive control unit 93 drives the swing rotation driving unit 17 to execute a second driving process in which the inspection head 20 is rotated by the tilt angle θ around the rotation axis 21 (see arrow R). As a result, as indicated by reference symbol XIIC in Fig. 12, the central axis CL of the inspection head 20 becomes parallel to the tilt axis TA. Note that the second driving process may be executed before the first driving process.

[0097] Next, after completing the second driving process, the drive control unit 93 starts a third driving process (see arrow XZ1) in which the X-axis driving unit 14 and the Z-axis driving unit 15 are driven to move the examination head 20 to the examination position along the tilt axis TA when viewed from above in the Y-axis direction. As a result, the examination head 20 is moved toward the subject's eye E while keeping the tilt angle θ constant (including approximately constant; the same applies hereinafter).

[0098] During such auto-alignment, the inspection head 20 is displaced to a position where the stereo camera 81L can capture an image of the anterior segment of the left eye OS and the alignment detection unit 92 can identify the pupil center position of the left eye OS, i.e., a position where alignment can be detected. As a result, the alignment detection unit 92 inputs the alignment detection result to the drive control unit 93. Note that, to enable alignment detection by the alignment detection unit 92, the Y-axis position of the inspection head 20 may be adjusted by the Y-axis drive unit 16 even before alignment detection (at any stage of the first drive process to the third drive process).

[0099] 12, the drive control unit 93 drives the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16 based on the alignment detection result input from the alignment detection unit 92, and continues the third drive process until the inspection head 20 reaches the inspection position. In the third drive process executed based on this alignment detection result, the position of the inspection head 20 in the Y-axis direction is also adjusted.

[0100] FIG. 13 is an explanatory diagram for explaining a first-second example of auto-alignment of the inspection head 20 in the first embodiment. The drive control unit 93 drives the X-axis drive unit 14 and the Z-axis drive unit 15 to first move the inspection head 20 forward in the Z-axis direction (toward the subject H) by a predetermined distance (see arrow Z1), as indicated by reference numeral XIIIA in FIG. 13 , and then executes a first drive process to move the inspection head 20 outward in the X1 direction to the tilt axis TA, as indicated by reference numeral XIIIB in FIG. 13 . Note that the distance by which the inspection head 20 moves forward in the Z-axis direction is not particularly limited as long as a safe distance can be ensured between the inspection head 20 (first concave mirror 51) and the nose N. For example, the distance in the Z-axis direction from the inspection head 20 to the nose N may be calculated based on images obtained by stereoscopically photographing the nose N using the stereo camera 81L, and the movement distance may be determined based on the calculation result.

[0101] In this way, by first moving the inspection head 20 forward in the Z-axis direction and then moving it in the outward direction X1 to the inclined axis TA, the distance over which the inspection head 20 is moved in the outward direction X1 can be reduced compared to Example 1-1 shown in Figure 12 described above.

[0102] As shown by reference symbol XIIIC in Fig. 13, after completing the first drive process, the drive control unit 93 drives the swing rotation drive unit 17 to execute a second drive process similar to that of the above-described Example 1-1 (see reference symbol XIIB in Fig. 12) to make the central axis CL parallel to the tilt axis TA. Note that, in Example 1-2 as well, the second drive process may be executed before the first drive process.

[0103] As shown by reference symbol XIIID in Fig. 13, after completing the second drive process, the drive control unit 93 drives the X-axis drive unit 14 and the Z-axis drive unit 15 to execute a third drive process similar to the above-described Example 1-1 (see reference symbols XIIC and XIID in Fig. 12), thereby moving the inspection head 20 to the inspection position along the tilt axis TA when viewed from above in the Y-axis direction. Then, as shown by reference symbol XIIIE in Fig. 13, the drive control unit 93 drives the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16 based on the alignment detection detected by the alignment detection unit 92 during the auto-alignment, and continues the third drive process until the inspection head 20 reaches the inspection position.

[0104] 14 is an explanatory diagram for explaining a first-third example of auto-alignment of the inspection head 20 in the first embodiment. As indicated by symbols XIVA and XIVB in FIG. 14, the drive control unit 93 drives the X-axis drive unit 14, the Z-axis drive unit 15, the Y-axis drive unit 16, and the swing rotation drive unit 17 to execute a first drive process that simultaneously moves the inspection head 20 forward and outward in the Z-axis direction X1 and rotates the inspection head 20 through a tilt angle θ (see arrows XZ2 and R). This allows the inspection head 20 to be moved obliquely to the tilt axis TA when viewed from above in the Y-axis direction, and the central axis CL to be parallel to the tilt axis TA.

[0105] In the first driving process of Example 1-3, the inspection head 20 may be displaced over the shortest distance on the tilt axis TA to a position where the stereo camera 81L can capture an image of the anterior segment of the left eye OS.

[0106] As indicated by reference symbol XIVC in FIG. 14, after completing the first drive process, the drive control unit 93 drives the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16 to perform the second drive process. The second drive process in Example 1-3 is similar to the third drive process in Examples 1-1 and 1-2 described above, and moves the inspection head 20 to the inspection position along the tilt axis TA when viewed from above in the Y-axis direction. Then, as indicated by reference symbol XIVD in FIG. 14, the drive control unit 93 drives the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16 based on the alignment detection detected by the alignment detection unit 92 during the auto-alignment, and continues the second drive process until the inspection head 20 reaches the inspection position.

[0107] In the above-described auto-alignment examples 1-1 to 1-3, the auto-alignment of the inspection head 20 for the left eye OS has been described as an example, but the auto-alignment of the inspection head 20 for the right eye OD can also be performed in the same way.

[0108] Returning to Figure 10, when the fundus photographing of the test eye E is completed by the photographing optical system 60, the drive control unit 93 drives the Z-axis drive unit 15 to retract the examination head 20 a predetermined distance backward in the Z-axis direction (towards the examiner) (see symbols XVIID and XVIIG in Figure 17 described below).

[0109] The fixation control unit 94 causes the fixation light projection system 770 to project fixation light onto the subject's eye E at least from the start of auto-alignment of the examination head 20 until fundus photography of the subject's eye E by the examination head 20 is completed. This makes it possible to guide and fix the gaze direction of the subject H in the direction of the fixation light while the examination head 20 is moved from the initial position via the tilt axis TA to the examination position during auto-alignment. Therefore, for example, when the examination head 20 is moved from the initial position to the tilt axis TA, the subject's eye E can be rotated to follow this movement. As a result, the gaze direction of the subject's eye E can always be fixed to the examination head 20.

[0110] After completing the auto-alignment of the examination head 20, the fundus photography control unit 95 controls the fundus photography of the subject's eye E by the fundus camera 9. For example, the fundus photography control unit 95 drives the focusing drive unit 69 by a known method to focus the photographing optical system 60 (the photographing optical system for the left eye 60L or the photographing optical system for the right eye 60R) on the fundus of the subject's eye E, and also drives the slit drive unit 77 by a known method to perform focusing control to focus the illumination light (slit light) on the fundus of the subject's eye E.

[0111] Next, the fundus photography control unit 95 controls the scanner driving unit 78 and the photographing optical system 60 (the photographing optical system for the left eye 60L or the photographing optical system for the right eye 60R) by a known method to perform slit scan photography of the fundus, including scanning of the slit light on the fundus by the galvano scanner 37 and photographing the fundus at each scanning position of the slit light by the photographing optical system 60. As a result, the image forming unit 120 forms a fundus image of the subject's eye E based on the imaging signal output from one of the fundus image sensors 671L, 671R during slit scan photography, and the data processing unit 130 performs various image processing on this fundus image.

[0112] The storage control unit 96 displays the fundus image of the subject's eye E after image processing by the data processing unit 130 on the control panel 40. Furthermore, when the examiner inputs an image saving operation to the control panel 40, the storage control unit 96 saves the fundus image of the subject's eye E in the memory unit 131.

[0113] <Operation of the Fundus Camera of the First Embodiment> 15 is a flowchart showing the flow of fundus photographing processing of the subject's eye E by the fundus camera 9 of the first embodiment configured as described above. With the subject H previously resting his chin on the chin rest 33 and his forehead against the forehead rest frame 32, the examiner operates the control panel 40 to adjust the height position (position in the Y-axis direction) of the chin rest 33 to suit the subject H. The examiner also operates the control panel 40 to select auto-alignment mode as the alignment mode of the examination head 20. Furthermore, the fixation control unit 94 starts projecting fixation light onto the subject's eye E by the fixation light projection system 770. This makes it possible to guide and fix the gaze direction of the subject's eye E.

[0114] Furthermore, the examiner operates the control panel 40 to perform a selection operation to select, for example, the left eye OS (or the right eye OD) as the eye to be examined E. In response to this selection operation, the drive control unit 93 drives the unit rotation drive unit 55 to rotate the concave mirror unit 50 to a first position (see FIG. 4) corresponding to the left eye OS (step S1). Note that the processing of step S1 may be performed simultaneously with auto-alignment of the examination head 20 (step S2).

[0115] When the examiner inputs an examination start operation to the control panel 40, automatic alignment of the examination head 20 with respect to the subject's eye E (here, the left eye OS) starts (step S2).

[0116] Fig. 16 is a flowchart showing the flow of auto-alignment processing of the examination head 20 in accordance with the method for operating an ophthalmic apparatus of the present invention. Fig. 17 is an explanatory diagram for explaining the displacement of the examination head 20 after the start of auto-alignment. Note that the following description will be given taking as an example a case where auto-alignment of "Example 1-1" shown in Fig. 12 is performed.

[0117] 16 and 17, the tilt angle determination unit 91 determines the angle selected in advance by the examiner on the control panel 40 as the tilt angle θ, and then outputs information about this tilt angle θ to the drive control unit 93 (step S2A). As a result, the drive control unit 93 determines the tilt axis TA based on this tilt angle θ, and then starts auto-alignment of the inspection head 20 (step S2B).

[0118] First, the drive control unit 93 drives the X-axis drive unit 14 to execute a first drive process to move the inspection head 20 outward in the X1 direction from the initial position to the tilt axis TA when viewed from above in the Y-axis direction (step S2C). In addition, the alignment detection unit 92 starts stereo photography by the stereo camera 81L, and continuously acquires photographed images from the stereo camera 81L and analyzes each photographed image (step S2D).

[0119] Next, the drive control unit 93 executes a second drive process (step S2E) in which the swing rotation drive unit 17 rotates the inspection head 20 by the tilt angle θ around the rotation axis 21, thereby making the central axis CL of the inspection head 20 parallel to the tilt axis TA. As a result, the inspection head 20 is displaced from the initial position indicated by reference symbol XVIIA in Fig. 17 to the tilt axis TA as indicated by reference symbol XVIIB, and the central axis CL becomes parallel to the tilt axis TA. Note that the projection of fixation light by the fixation light projection system 770 allows the line of sight of the subject's eye E (left eye OS) to follow the displacement of the inspection head 20.

[0120] Then, the drive control unit 93 drives the X-axis drive unit 14 and the Z-axis drive unit 15 to start a third drive process (step S2F) in which the inspection head 20 is moved along the inclined axis TA to the inspection position when viewed from above in the Y-axis direction, as shown by symbol XVIIC in Figure 17.

[0121] While the first to third drive processes are being executed, the alignment detection unit 92 waits for alignment detection until it is possible to identify the pupil center position of the left eye OS from the captured image acquired by the stereo camera 81L (NO in step S2G). Then, during the auto-alignment, the stereo camera 81L captures an image of the anterior segment of the left eye OS, and the image of the anterior segment of the left eye OS is input from the stereo camera 81L to the alignment detection unit 92. This enables the alignment detection unit 92 to identify the pupil center position of the left eye OS based on the anterior segment image input from the stereo camera 81L (YES in step S2G).

[0122] Next, the alignment detection unit 92 converts the pupil center position of the left eye OS into three-dimensional coordinates, thereby performing alignment detection to detect the relative position of the left eye OS with respect to the inspection head 20 (step S2H). Then, the alignment detection unit 92 outputs the detection result of the alignment detection to the drive control unit 93.

[0123] Based on the alignment detection result input from the alignment detection unit 92, the drive control unit 93 drives the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16 to continue the third drive process until the inspection head 20 reaches the inspection position. Specifically, the drive control unit 93 calculates the difference between the three-dimensional coordinates (target coordinates) of the inspection position determined based on the alignment detection result and the three-dimensional coordinates (current coordinates) of the current inspection head 20, and continues the third drive process until this difference becomes equal to or less than a threshold value (step S2I, NO in step S2J, step S2K). As a result, the inspection head 20 is moved to the inspection position while maintaining the tilt angle θ.

[0124] When the difference between the target coordinates and the current coordinates becomes equal to or smaller than the threshold value, the drive control unit 93 stops driving the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16, and ends the auto-alignment (YES in step S2J). By displacing the inspection head 20 along the tilt axis TA to the inspection position during auto-alignment in this way, the inspection head 20 (first concave mirror 51) is prevented from approaching the nose N.

[0125] Fig. 18 is a flowchart showing the flow of a modified example of auto-alignment of the inspection head 20. In Fig. 16, alignment detection is performed by the alignment detection unit 92 during auto-alignment, but there are cases where the alignment detection unit 92 is unable to detect alignment even when the inspection head 20 reaches an area where this alignment detection is possible.

[0126] 18, if the alignment detection unit 92 cannot identify the pupil center position of the left eye OS while the inspection head 20 moves for a predetermined time or a predetermined distance from the start of auto-alignment or the start of the third driving process, the drive control unit 93 determines that alignment detection is impossible (NO in step S2G, YES in step S2L). In this case, the drive control unit 93 switches the alignment mode of the inspection head 20 from auto-alignment mode to manual alignment mode and displays this on the control panel 40 (step S2M). This allows the examiner to operate the control panel 40 to perform manual alignment of the inspection head 20. By making it possible to switch to manual alignment in the middle of auto-alignment in this way, the inspection head 20 is prevented from approaching the face of the subject H when alignment detection is impossible.

[0127] 15 and 17, when the auto-alignment is completed, the fundus photography control unit 95 drives the focusing drive unit 69 and the slit drive unit 77 by a known method to perform focusing control to focus the photographing optical system 60 (here, the photographing optical system for the left eye 60L) and the illumination light (slit light) on the fundus of the left eye OS (step S3). Next, the fundus photography control unit 95 controls the scanner drive unit 78 and the photographing optical system for the left eye 60L by a known method to perform slit scan photography of the fundus of the left eye OS (step S4).

[0128] The image forming unit 120 forms a fundus image of the left eye OS based on the imaging signal output from the fundus image sensor 671L by slit scan photography, and the data processing unit 130 performs various image processing on the fundus image of the left eye OS. This fundus image of the left eye OS is output from the data processing unit 130 to the storage control unit 96.

[0129] On the other hand, when fundus photography of the left eye OS is completed, the drive control unit 93 drives the Z-axis drive unit 15 to retract the inspection head 20 backward in the Z-axis direction as shown by symbol XVIID in Figure 17 (step S5).

[0130] The storage control unit 96 displays the fundus image of the left eye OS input from the data processing unit 130 on the control panel 40. This allows the examiner to confirm whether or not the desired fundus image has been obtained. Then, when the desired fundus image has been obtained, the examiner inputs an image saving operation to the control panel 40. This causes the saving control unit 96 to save the fundus image of the left eye OS in the memory unit 131 (step S6).

[0131] If fundus photography of the right eye OD is to be performed subsequently, the processes of steps S1 to S6 are repeatedly executed (YES in step S7). In this case, under the control of the drive control unit 93, the concave mirror unit 50 is rotated to the second position corresponding to the right eye OD (see FIG. 5). The examination head 20 is also displaced to the tilt axis TA corresponding to the right eye OD (see symbol XVIIE in FIG. 17), and further moved along the tilt axis TA to the examination position for the right eye OD (see symbol XVIIF in FIG. 17). Then, when fundus photography of the right eye OD is completed, under the control of the drive control unit 93, the examination head 20 is retracted backward in the Z-axis direction (see symbol XVIIG in FIG. 17), and then displaced to the initial position (see symbol XVIIH in FIG. 17).

[0132] As described above, in the fundus camera 9 of the first embodiment, the examination head 20 can be moved obliquely along the tilt axis TA to the examination position of the subject's eye E during auto-alignment. This makes it possible to always ensure a sufficient distance between the examination head 20 (first concave mirror 51) and the nose N compared to when the examination head 20 is moved from a position directly in front of the subject's eye E to an examination position forward in the Z axis direction (see symbol XIA in FIG. 11 ). As a result, the examination of the subject's eye E by the examination head 20 can be performed without bringing the examination head 20 (first concave mirror 51) close to the nose N.

[0133] [Second embodiment] Fig. 19 is a side view of the main parts of the fundus camera 9 of the second embodiment. In the fundus camera 9 of the first embodiment, the examination head 20 is rotated (swinged) by the swing rotation drive unit 17 around a rotation axis 21 provided on the lower side of the examination head 20 in the Y-axis direction, but as shown in Fig. 19, in the fundus camera 9 of the second embodiment, the position of the rotation axis 21 is different from that of the first embodiment.

[0134] The fundus camera 9 of the second embodiment has basically the same configuration as the fundus camera 9 of the first embodiment, except for the position of the rotation axis 21. Therefore, parts that are the same in function or configuration as the fundus camera 9 of the first embodiment are given the same reference numerals and their description will be omitted.

[0135] The swing rotation drive unit 17 and the rotation axis 21 in the second embodiment are provided at a position closer to the subject's eye E than the examination head 20, i.e., on the front side in the Z axis direction of the examination head 20. As a result, by adjusting the XZ position of the swing rotation drive unit 17 using the X axis drive unit 14 and the Z axis drive unit 15, it is possible to align the rotation axis 21 with the subject's eye E (center of rotation) when viewed from above in the Y axis direction. In this case, the swing rotation drive unit 17 rotates (swings) the examination head 20 around the center of rotation of the subject's eye E.

[0136] The control device 90 of the second embodiment is basically the same as the control device 90 of the first embodiment, except that the method of auto-alignment of the inspection head 20 by the drive control unit 93 is different from that of the first embodiment.

[0137] As in the first embodiment, the drive control unit 93 of the second embodiment determines the tilt axis TA based on the tilt angle θ determined by the tilt angle determination unit 91, and then drives the X-axis drive unit 14, the Z-axis drive unit 15, the Y-axis drive unit 16, and the swing rotation drive unit 17 to perform auto-alignment of the inspection head 20.

[0138] 20 is an explanatory diagram for explaining Example 2-1 of auto-alignment of the inspection head 20 in the second embodiment. As shown by the reference symbol XXA in Fig. 20, the inspection head 20 is initially placed in the same initial position as in the first embodiment.

[0139] 20, the drive control unit 93 executes a first drive process (see arrow XZ2) in which the X-axis drive unit 14 and the Z-axis drive unit 15 are driven to move the examination head 20 (the swing rotation drive unit 17 and the rotation axis 21) from the initial position in the XZ-axis direction (see arrow XZ2). Specifically, the examination head 20 is moved in the XZ-axis direction to a position where the rotation axis 21 coincides with the center of rotation of the subject's eye E when viewed from above in the Y-axis direction.

[0140] After completing the first driving process, the drive control unit 93 drives the swing rotation driving unit 17 to execute a second driving process (see arrow R) in which the examination head 20 is rotated by the tilt angle θ around the rotation axis 21 (the center of rotation of the subject's eye E) as shown by reference symbol XXB in Fig. 20. As a result, as shown by reference symbol XXC in Fig. 20, the examination head 20 is moved to the tilt axis TA and the central axis CL becomes parallel to the tilt axis TA.

[0141] Next, after completing the second driving process, the drive control unit 93 drives the X-axis driving unit 14 and the Z-axis driving unit 15 to start a third driving process in which the inspection head 20 is moved to the inspection position along the tilt axis TA when viewed from above in the Y-axis direction, as in the first embodiment (see arrow XZ1). Note that, unlike the first embodiment, the third driving process in the second embodiment mainly involves moving the inspection head 20 along the Z axis by the X-axis driving unit 14 and the Z-axis driving unit 15. As a result, the inspection head 20 is moved toward the eye E while maintaining a constant tilt angle θ.

[0142] Then, as shown by the symbol XXD in Figure 20, the drive control unit 93 drives the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16 based on the alignment detection detected by the alignment detection unit 92 during the auto-alignment, and continues the third drive process until the inspection head 20 reaches the inspection position.

[0143] As explained above in Figure 18, if the alignment detection unit 92 is unable to perform alignment detection while the inspection head 20 moves for a predetermined fixed time or distance from the start of auto alignment or the start of the third drive process, the drive control unit 93 switches the alignment mode of the inspection head 20 to manual alignment mode.

[0144] FIG. 21 is an explanatory diagram for explaining Example 2-2 of auto-alignment of the inspection head 20 in the second embodiment. As indicated by reference numerals XXIA and XXIB in FIG. 21, the drive control unit 93 simultaneously drives the X-axis drive unit 14, the Z-axis drive unit 15, the Y-axis drive unit 16, and the swing rotation drive unit 17 to perform a first drive process that simultaneously moves the inspection head 20 in the XZ axis directions (see arrow XZ2) and rotates the inspection head 20 through a tilt angle θ (see arrow R). Note that the first drive process of Example 2-2 is a process that simultaneously executes the first drive process and the second drive process of Example 2-1 described in FIG. 20. As a result, the inspection head 20 is moved to the tilt axis TA, and the central axis CL of the inspection head 20 becomes parallel to the tilt axis TA.

[0145] In the first drive process, the inspection head 20 may be displaced over the shortest distance on the tilt axis TA to a position where the stereo cameras 81L and 81R can photograph the anterior segment of the subject's eye E (here, the left eye OS), or to a position where an observation optical system (not shown) in the inspection head 20 can photograph the anterior segment of the subject's eye E.

[0146] After completing the first drive process, the drive control unit 93 drives the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16 to execute a second drive process similar to the third drive process of the above-described "Example 2-1," thereby moving the inspection head 20 to the inspection position along the tilt axis TA when viewed from above in the Y-axis direction (see arrow XZ1). Then, as shown by symbol XXIC in Fig. 21, the drive control unit 93 drives the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16 based on the alignment detection detected by the alignment detection unit 92 during the auto-alignment, and continues the second drive process until the inspection head 20 reaches the inspection position.

[0147] As described above, in the fundus camera 9 of the second embodiment, as in the first embodiment, the examination head 20 can be moved obliquely along the tilt axis TA to the examination position of the subject's eye E during auto-alignment, thereby achieving the same effect as in the first embodiment.

[0148] [Third embodiment] 22 is a side view of the main parts of the fundus camera 9 of the third embodiment. In the fundus camera 9 of the first embodiment, the examination head 20 approaches the subject's eye E along an inclined axis TA obtained by inclining the reference axis VA in the X-axis direction (outward direction X1) during auto-alignment of the examination head 20. In contrast, in the fundus camera 9 of the third embodiment, the examination head 20 approaches the subject's eye E along an inclined axis TA obtained by inclining the reference axis VA in a direction different from the X-axis direction during auto-alignment of the examination head 20.

[0149] 22, the fundus camera 9 of the third embodiment has basically the same configuration as the fundus camera 9 of the first embodiment, except that the examination head 20 is rotatable about the rotation axes 21, 140, that it is provided with a tilt rotation drive unit 141, and that it performs auto-alignment of the examination head 20, which is different from the first embodiment. Therefore, components that are the same in function or configuration as the fundus camera 9 of the first embodiment are given the same reference numerals and their description will be omitted.

[0150] The rotation shaft 140 is provided between the bottom surface of the inspection head 20 and the tip of the rotation shaft 21. The rotation shaft 140 is perpendicular to the Y-axis direction and holds the inspection head 20 rotatably around an axis perpendicular to the Y-axis direction. This allows the inspection head 20 to rotate (tilt: see arrow TL) around the rotation shaft 140 and rotate (swing: see arrow SW) around the rotation shaft 21. Note that the configurations of the rotation shafts 21 and 140 are not particularly limited as long as the inspection head 20 can be swung and tilted.

[0151] The tilt rotation drive unit 141 corresponds to the rotation mechanism of the present invention. The tilt rotation drive unit 141, together with the already-described X-axis drive unit 14, Z-axis drive unit 15, Y-axis drive unit 16, and swing rotation drive unit 17, constitutes a displacement mechanism of the present invention. The tilt rotation drive unit 141 includes, for example, a motor, a worm gear, and a motor drive circuit, and rotates (tilts) the inspection head 20 around the rotation axis 140.

[0152] As described above, the examination head 20 of the third embodiment can rotate (swing and tilt) on two axes by the swing rotation drive unit 17 and the tilt rotation drive unit 141. For this reason, in the third embodiment, a direction other than the outward direction X1 of the first embodiment (a direction perpendicular to the Z-axis direction and away from the nose N), for example, an upward direction in the Y-axis direction, is defined as the "outward direction Y1 (see FIG. 23)," and an axis obtained by tilting the reference axis VA in the "outward direction Y1" around the subject's eye E is defined as the tilt axis TA.

[0153] The control device 90 of the third embodiment is basically the same as the control device 90 of the first embodiment, except that the tilt direction of the tilt axis TA is different from that of the first embodiment.

[0154] The tilt angle determination unit 91 of the third embodiment determines the tilt angle θ of the tilt axis TA in the outward direction Y1 (see FIG. 23) with respect to the reference axis VA when viewed from one side in the X-axis direction, i.e., the tilt angle θ of the tilt axis TA with respect to the reference axis VA in the YZ plane. Note that the specific method for determining the tilt angle θ is the same as the method for determining the tilt angle θ in the first embodiment, except for the tilt direction of the tilt axis TA, and therefore a detailed description thereof will be omitted here.

[0155] The drive control unit 93 of the third embodiment determines the tilt axis TA based on the tilt angle θ determined by the tilt angle determination unit 91, and then drives the X-axis drive unit 14, the Z-axis drive unit 15, the Y-axis drive unit 16, the swing rotation drive unit 17, and the tilt rotation drive unit 141 to perform auto-alignment of the inspection head 20.

[0156] 23 is an explanatory diagram for explaining a third example of auto-alignment of the inspection head 20 in the third embodiment. Note that this third example is basically the same as Example 1-1 (see FIG. 12) described in the first embodiment above, except that the tilt direction of the tilt axis TA is different.

[0157] 23A, the inspection head 20 is initially placed in the same initial position as in the first embodiment. The drive control unit 93 of the third embodiment drives the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16 to execute a first drive process that moves the inspection head 20 from the initial position to the tilt axis TA in the outward direction Y1 (upward in the Y-axis direction) when viewed from one side in the X-axis direction.

[0158] As shown by reference symbol XXIIIB in Fig. 23, after completing the first driving process, the drive control unit 93 drives the tilt rotation driving unit 141 to execute a second driving process in which the inspection head 20 is rotated by the tilt angle θ around the rotation axis 140 (see arrow R). As a result, as shown by reference symbol XXIIIC in Fig. 23, the central axis CL of the inspection head 20 becomes parallel to the tilt axis TA. Note that the second driving process may be executed before the first driving process.

[0159] Next, after completing the second driving process, the drive control unit 93 starts a third driving process in which the X-axis driving unit 14, the Z-axis driving unit 15, and the Y-axis driving unit 16 are driven to move the examination head 20 to the examination position along the tilt axis TA when viewed from one side in the X-axis direction (see arrow YZ1). As a result, the examination head 20 is moved toward the subject's eye E while keeping the tilt angle θ constant (including approximately constant; the same applies hereinafter).

[0160] Then, as shown by symbol XXIIID in Figure 23, the drive control unit 93 drives the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16 based on the alignment detection detected by the alignment detection unit 92 during the auto-alignment, and continues the third drive process until the inspection head 20 reaches the inspection position.

[0161] At this time, if the alignment detection unit 92 is unable to perform alignment detection while the inspection head 20 moves for a predetermined fixed time or a predetermined distance from the start of auto-alignment or the start of the third drive process, the drive control unit 93 switches the alignment mode of the inspection head 20 to manual alignment mode (see Figure 18).

[0162] As in Example 1-2 of the auto-alignment of the inspection head 20 of the first embodiment (see FIG. 13), the inspection head 20 may first be moved a predetermined distance forward in the Z-axis direction (toward the eye E to be inspected), and then the above-described first driving process may be started. Also, as in Example 1-3 of the auto-alignment of the inspection head 20 of the first embodiment (see FIG. 14), the first driving process may be executed to simultaneously move the inspection head 20 forward in the Z-axis direction and outward in the Y1 direction and rotate the inspection head 20 by the tilt angle θ.

[0163] As described above, in the fundus camera 9 of the third embodiment, the examination head 20 can also be moved along the tilt axis TA from an oblique direction (diagonally upward) to the examination position of the subject's eye E during auto-alignment, preventing the examination head 20 (first concave mirror 51) from approaching the nose N. As a result, the same effects as in the first embodiment can be obtained.

[0164] In the third embodiment, during auto-alignment of the examination head 20, the examination head 20 is moved toward the subject's eye E along the tilt axis TA, which is obtained by tilting the reference axis VA in the outward direction Y1 (upward in the Y-axis direction) with the subject's eye E as the center, but the tilt direction of this tilt axis TA is not particularly limited as long as it is perpendicular to the Z-axis direction and away from the nose N. Furthermore, the direction and configuration of the rotation axes 21, 140 can also be changed as appropriate depending on this tilt direction.

[0165] Furthermore, in the fundus camera 9 of the third embodiment, when the tilt direction of the tilt axis TA is fixed to the outward direction Y1, the swing rotation drive unit 17 may be omitted.

[0166] [Fourth embodiment] Next, a fundus camera 9 according to a fourth embodiment of the present invention will be described. In the fundus camera 9 according to the second embodiment (see FIG. 19), the examination head 20 approaches the subject's eye E along an inclined axis TA obtained by inclining the reference axis VA in the X-axis direction (outward direction X1) during auto-alignment of the examination head 20. In contrast, in the fundus camera 9 according to the fourth embodiment, the examination head 20 approaches the subject's eye E along an inclined axis TA obtained by inclining the reference axis VA in the outward direction Y1 (upward in the Y-axis direction), similar to the fundus camera 9 according to the third embodiment (see FIGS. 22 and 23).

[0167] Although not shown, the fundus camera 9 of the fourth embodiment has basically the same configuration as the fundus camera 9 of the second embodiment, except that, like the fundus camera 9 of the third embodiment (see FIG. 22), the examination head 20 can be rotated (swing-tilt) about two axes, a rotation axis 21 (corresponding to the first rotation axis of the present invention) and a rotation axis 140 (corresponding to the second rotation axis of the present invention). Therefore, components identical in function or configuration to those of the fundus camera 9 of each of the above-described embodiments are denoted by the same reference numerals, and a description thereof will be omitted. The specific configuration of the tilt mechanism (rotation axis 140 and tilt rotation drive unit 141) employed in the fundus camera 9 of the fourth embodiment is a known technique (see, for example, JP 2022-112637 A), and therefore a detailed description thereof will be omitted here.

[0168] The control device 90 of the fourth embodiment is basically the same as the control device 90 of the second embodiment, except that the tilt direction of the tilt axis TA is different from that of the second embodiment. Similarly to the tilt angle determination unit 91 of the third embodiment, the tilt angle determination unit 91 of the fourth embodiment determines the tilt angle θ of the tilt axis TA in the outward direction Y1 with respect to the reference axis VA. Furthermore, the drive control unit 93 of the fourth embodiment drives the X-axis drive unit 14, the Z-axis drive unit 15, the Y-axis drive unit 16, the swing rotation drive unit 17, and the tilt rotation drive unit 141 to perform auto-alignment of the inspection head 20.

[0169] 24 is an explanatory diagram for explaining a fourth example of auto-alignment of the inspection head 20 in the fourth embodiment. Note that this fourth example is basically the same as Example 2-1 (see FIG. 20) described in the second embodiment above, except for the tilt direction of the tilt axis TA. As shown by reference symbol XIVA in FIG. 24, the inspection head 20 is initially placed in the same initial position as in the first embodiment.

[0170] Next, as shown by symbols XIVA and XXIVB in Figure 24, the drive control unit 93 drives the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16 to perform a first drive process in which the examination head 20 is moved in the XYZ axis directions to a position where the rotation axis 21 and the rotation axis 140 coincide with the center of rotation of the test eye E.

[0171] After completing the first driving process, the drive control unit 93 drives the tilt rotation driving unit 141 to execute a second driving process (see arrow R) in which the examination head 20 is rotated in the outward direction Y1 by the tilt angle θ around the rotation axis 140 (the center of rotation of the subject's eye E). As a result, as shown by symbol XXIVC in Fig. 24 , the examination head 20 is moved to the tilt axis TA and the central axis CL becomes parallel to the tilt axis TA.

[0172] Next, after completing the second driving process, the drive control unit 93 starts a third driving process in which the X-axis driving unit 14, the Z-axis driving unit 15, and the Y-axis driving unit 16 are driven to move the examination head 20 to the examination position along the tilt axis TA when viewed from one side in the X-axis direction (see arrow YZ1). As a result, the examination head 20 is moved toward the subject's eye E while keeping the tilt angle θ constant (including approximately constant; the same applies hereinafter).

[0173] Then, as shown by symbol XXIVD in Figure 24, the drive control unit 93 drives the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16 based on the alignment detection detected by the alignment detection unit 92 during the auto-alignment, and continues the third drive process until the inspection head 20 reaches the inspection position.

[0174] At this time, if the alignment detection unit 92 is unable to perform alignment detection while the inspection head 20 moves for a predetermined fixed time or a predetermined distance from the start of auto-alignment or the start of the third drive process, the drive control unit 93 switches the alignment mode of the inspection head 20 to manual alignment mode (see Figure 18).

[0175] It should be noted that the first drive process and the second drive process may be executed simultaneously, as in Example 2-2 of the auto-alignment of the inspection head 20 of the second embodiment (see FIG. 21).

[0176] As described above, in the fundus camera 9 of the fourth embodiment, the examination head 20 can also be moved along the tilt axis TA from an oblique direction (diagonally upward) to the examination position of the subject's eye E during auto-alignment, preventing the examination head 20 (first concave mirror 51) from approaching the nose N. As a result, the same effects as those of the second embodiment can be obtained.

[0177] In the fourth embodiment, during auto-alignment of the examination head 20, the examination head 20 is moved closer to the subject's eye E along the tilt axis TA, which is obtained by tilting the reference axis VA in the outward direction Y1 (upward in the Y-axis direction) with the subject's eye E as the center, but the tilt direction of the tilt axis TA with the subject's eye E as the center is not particularly limited as long as it is perpendicular to the Z-axis direction and points away from the nose N. Furthermore, the direction and configuration of the rotation axes 21, 140 can also be changed as appropriate depending on this tilt direction.

[0178] Furthermore, in the fundus camera 9 of the fourth embodiment, when the tilt direction of the tilt axis TA is fixed to the outward direction Y1, the swing rotation drive unit 17 may be omitted.

[0179] [others] In each of the above embodiments, alignment detection is performed using the stereo cameras 81L and 81R, but alignment detection may also be performed using various imaging units other than the stereo cameras 81L and 81R provided in the inspection head 20. In this case, the stereo cameras 81L and 81R can be omitted.

[0180] In each of the above embodiments, during auto-alignment, the inspection head 20 is moved obliquely along the tilt axis TA to the inspection position of the subject's eye E, but during manual alignment, the inspection head 20 may also be moved obliquely along the tilt axis TA to the inspection position of the subject's eye E.

[0181] In the above-described embodiments, the displacement mechanism for displacing the examination head 20 relative to the subject's eye E is configured by the X-axis drive unit 14, the Z-axis drive unit 15, the Y-axis drive unit 16, and the swing rotation drive unit 17, and is further configured by the tilt rotation drive unit 141. However, the configuration and type of this displacement mechanism are not particularly limited. For example, a robot arm (multi-joint arm) may be used as the displacement mechanism of the present invention.

[0182] In each of the above embodiments, a fundus camera 9 has been used as an example of an ophthalmic device of the present invention, but the present invention is not limited to this, and can be applied to various ophthalmic devices that perform examinations (eye characteristic measurements, photography, observation, etc.) of various parts of the subject's eye E via a pair of concave mirrors. [Explanation of symbols]

[0183] 9. Fundus camera 10...Device stand 11...X-axis movable frame 12...Z-axis movable frame 13...Y-axis movable frame 14...X-axis drive unit 15...Z-axis drive unit 16...Y-axis drive unit 17...Swing rotation drive unit 20...Inspection head 21...Rotation axis 22L, 22R...Alignment optical frame 30...Face support part 31...Main body 32...Frame holder 32a...Forehead support for left eye 32b...Forehead surface for right eye 33...Chin rest 33a...Chin rest for left eye 33b…Right eye chin rest surface 34...Lifting rod 35...Chin rest drive unit 37...Galvanometer scanner 40...Control Panel 41...Touch panel screen 50...Concave mirror unit 51...1st concave mirror 51a...first reflective surface 52…Second concave mirror 52a…Second reflective surface 53...Concave mirror bracket 54...Unit rotation axis 55...Unit rotation drive part 57L...Dichroic mirror 57R...Dichroic mirror 60...Photographing optical system 60L...Left-eye imaging optical system 60R…Photography optical system for right eye 61L, 61R...First reflecting mirror 62L, 62R...First lens unit 63L, 63R...Second reflecting mirror 64L, 64R...Second lens unit 65L, 65R...Focusing lenses 66L, 66R...Third lens unit 67L, 67R...imaging unit 68...Slide plate 69...Focusing drive unit 70...Illumination optical system 71...Light source section 71a...Iris diaphragm 72...Slit unit 72a...Slit 72b...Projection lens 73...Galvanometer scanner 75...Left and right switchable mirror 75a...Mirror rotation axis 77...Slit drive unit 78...Scanner drive unit 79...Mirror rotation drive unit 80...Alignment optical system 80L: Alignment optical system for left eye 80R...Alignment optical system for the right eye 81L, 81R...Stereo camera 82L, 82R...Alignment lighting lamp 90...Control device 91...Tilt angle determination unit 92...Alignment detection unit 93...Drive control unit 94...Fixation control unit 95...Fundus photography control unit 96...Storage control unit 120...Image forming unit 130...Data processing unit 131...Storage section 140...Rotation axis 141...Tilt rotation drive unit 600L...shooting aperture 600R...Aperture 671L, 671R...Fundus image sensor 741...First reflecting mirror 742...Second reflecting mirror 744L, 744R...4th reflecting mirror 761L, 761R...First lens unit 762L, 762R... Second lens unit 763L, 763R...Third reflecting mirror 770…Fixation light projection system CL…Central axis E...Examined eye F1…1st focal point F2…Second focal point F3…Third focal point F4…4th focal point H...Subject N…Nose OD…Right eye OS…Left eye T...Optical table TA...Tilt axis VA: Reference axis X1…outward direction Y1…outward direction θ...Tilt angle

Claims

1. an examination head including an illumination optical system that emits illumination light to illuminate the subject's eye, and an imaging optical system that guides return light from the subject's eye illuminated with the illumination light to an imaging element; a pair of concave mirrors provided in the examination head and forming optical paths of the illumination light and the return light between the examination head and the subject's eye; a displacement mechanism that displaces the examination head relative to the eye to be examined; Equipped with An ophthalmic device in which an axis that is parallel to the front-to-back direction, which is the working distance direction of the examination head, and that passes through the subject's eye is defined as a reference axis, and an axis that is tilted outward from the reference axis, away from the subject's nose, with the subject's eye as the center, is defined as an inclination axis, and the displacement mechanism displaces the examination head along the inclination axis to an examination position for the subject's eye.

2. 2. The ophthalmologic apparatus according to claim 1, wherein the displacement mechanism displaces the examination head to the examination position while maintaining a constant tilt angle of the tilt axis relative to the reference axis.

3. The displacement mechanism a movement mechanism that moves the examination head in the front-back direction, the left-right direction, and the up-down direction relative to the eye to be examined; a rotation mechanism that rotates the inspection head around a predetermined rotation axis; The ophthalmic device of claim 2 .

4. the rotation axis is parallel to the vertical direction, The ophthalmic apparatus according to claim 3 , wherein the outward direction is parallel to the left-right direction.

5. the rotation axis is perpendicular to the up-down direction, The ophthalmic apparatus according to claim 3 , wherein the outward direction is an upward direction in the vertical direction.

6. the rotation shaft is provided below the inspection head, The ophthalmologic apparatus according to claim 3 , wherein the movement mechanism moves the examination head and the rotation shaft together in the front-rear direction, the left-right direction, and the up-down direction.

7. the rotation axis is parallel to the up-down direction and the outward direction is parallel to the left-right direction, the inspection head is at the center of the range of movement of the movement mechanism in the left-right direction at its initial position; When the inspection head is in the initial position, a central axis of the inspection head is parallel to the front-rear direction and is located at the central position when viewed from one side in the up-down direction, a drive control unit for controlling the drive of the displacement mechanism, The drive control unit a first driving process for driving the moving mechanism to move the inspection head in the outward direction from the initial position to the tilt axis; a second driving process of driving the rotation mechanism to rotate the inspection head around the rotation axis so that the central axis is parallel to the tilt axis; a third driving process of driving the moving mechanism after the first driving process and the second driving process are completed, to move the inspection head along the tilt axis to the inspection position; The ophthalmic apparatus according to claim 6, wherein the ophthalmic apparatus executes the above.

8. the rotation axis is parallel to the up-down direction and the outward direction is parallel to the left-right direction, the inspection head is at the center of the range of movement of the movement mechanism in the left-right direction at its initial position; When the inspection head is in the initial position, a central axis of the inspection head is parallel to the front-rear direction and is located at the central position when viewed from one side in the up-down direction, a drive control unit for controlling the drive of the displacement mechanism, The drive control unit a first driving process of driving the moving mechanism to move the examination head from the initial position toward the eye to be examined in the front-rear direction, and then moving the examination head in the outward direction to the tilt axis; a second driving process of driving the rotation mechanism to rotate the inspection head around the rotation axis so that the central axis is parallel to the tilt axis; a third driving process of driving the moving mechanism after the first driving process and the second driving process are completed, to move the inspection head along the tilt axis to the inspection position; The ophthalmic apparatus according to claim 6, wherein the ophthalmic apparatus executes the above.

9. the rotation axis is parallel to the up-down direction and the outward direction is parallel to the left-right direction, the inspection head is at the center of the range of movement of the movement mechanism in the left-right direction at its initial position; When the inspection head is in the initial position, a central axis of the inspection head is parallel to the front-rear direction and is located at the central position when viewed from one side in the up-down direction, a drive control unit for controlling the drive of the displacement mechanism, The drive control unit a first driving process that drives the moving mechanism and the rotating mechanism to simultaneously move the examination head forward in the front-to-back direction toward the eye to be examined, move the examination head in the outward direction, and rotate the examination head around the rotation axis, thereby moving the examination head to the tilt axis and making the central axis parallel to the tilt axis; a second driving process for driving the moving mechanism after completion of the first driving process to move the inspection head along the tilt axis to the inspection position; The ophthalmic apparatus according to claim 6, wherein the ophthalmic apparatus executes the above.

10. the rotation axis is perpendicular to the vertical direction and the outward direction is above the vertical direction, the inspection head is at the center of the range of movement of the movement mechanism in the left-right direction at its initial position; When the inspection head is in the initial position, a central axis of the inspection head is parallel to the front-rear direction and is located at the central position when viewed from one side in the up-down direction, a drive control unit for controlling the drive of the displacement mechanism, The drive control unit a first driving process for driving the moving mechanism and the rotating mechanism to move the inspection head to the tilt axis and make the central axis parallel to the tilt axis; a second driving process for driving the moving mechanism after completion of the first driving process to move the inspection head along the tilt axis to the inspection position; The ophthalmic apparatus according to claim 6, wherein the ophthalmic apparatus executes the above.

11. the rotation axis is located on the front side in the front-rear direction closer to the eye to be examined than the examination head, The ophthalmologic apparatus according to claim 3 , wherein the movement mechanism moves the examination head and the rotation shaft together in the front-rear direction, the left-right direction, and the up-down direction.

12. the rotation axis is parallel to the up-down direction and the outward direction is parallel to the left-right direction, the inspection head is at the center of the range of movement of the movement mechanism in the left-right direction at its initial position; When the inspection head is in the initial position, a central axis of the inspection head is parallel to the front-rear direction and is located at the central position when viewed from one side in the up-down direction, a drive control unit for controlling the drive of the displacement mechanism, The drive control unit a first driving process for driving the moving mechanism to move the examination head to a position where the rotation axis coincides with the eye to be examined when viewed from the one direction; a second driving process in which, after completion of the first driving process, the rotation mechanism is driven to rotate the inspection head around the rotation axis, thereby moving the inspection head to the tilt axis and making the central axis parallel to the tilt axis; a third driving process of driving the moving mechanism after completion of the second driving process to move the inspection head along the tilt axis to the inspection position; The ophthalmic apparatus according to claim 11, wherein the ophthalmic apparatus executes the above.

13. the rotation axis is parallel to the up-down direction and the outward direction is parallel to the left-right direction, the inspection head is at the center of the range of movement of the movement mechanism in the left-right direction at its initial position; When the inspection head is in the initial position, a central axis of the inspection head is parallel to the front-rear direction and is located at the central position when viewed from one side in the up-down direction, a drive control unit for controlling the drive of the displacement mechanism, The drive control unit a first driving process that simultaneously executes a process of driving the moving mechanism to move the examination head to a position where the rotation axis coincides with the eye to be examined when viewed from the one direction side, and a process of driving the rotation mechanism to rotate the examination head around the rotation axis, thereby moving the examination head to the tilt axis and making the central axis parallel to the tilt axis; a second driving process for driving the moving mechanism after completion of the first driving process to move the inspection head along the tilt axis to the inspection position; The ophthalmic apparatus according to claim 11, wherein the ophthalmic apparatus executes the above.

14. The ophthalmic apparatus according to claim 11, wherein the rotation mechanism is capable of rotating the examination head about a first rotation axis that is parallel to the vertical direction and a second rotation axis that is perpendicular to the vertical direction.

15. the inspection head is at the center of the range of movement of the movement mechanism in the left-right direction at its initial position; When the inspection head is in the initial position, a central axis of the inspection head is parallel to the front-rear direction and is located at the central position when viewed from one side in the up-down direction, a drive control unit for controlling the drive of the displacement mechanism, The drive control unit a first driving process that executes a process of driving the moving mechanism to move the examination head to a position where the first rotation axis and the second rotation axis coincide with the eye to be examined, and a process of driving the rotation mechanism to rotate the examination head around at least one of the first rotation axis and the second rotation axis, thereby moving the examination head to the tilt axis and making the central axis parallel to the tilt axis; a second driving process for driving the moving mechanism after completion of the first driving process to move the inspection head along the tilt axis to the inspection position; The ophthalmic device according to claim 14, wherein the ophthalmic device executes the following.

16. The ophthalmologic apparatus according to claim 1 , further comprising a fixation light projection system that projects fixation light onto the subject's eye.

17. an imaging unit provided in the examination head and configured to image an anterior segment of the subject's eye during displacement of the examination head by the displacement mechanism; an alignment detection unit that detects a relative position of the subject's eye with respect to the examination head based on an anterior ocular segment image of the subject's eye captured by the imaging unit; a drive control unit that controls the drive of the displacement mechanism; Equipped with 16. The ophthalmic apparatus according to claim 1, wherein the drive control unit drives the displacement mechanism based on the detection result of the alignment detection unit to move the inspection head along the tilt axis to the inspection position.

18. Equipped with an operating unit, the drive control unit is switchable to a manual control mode in which the drive control unit drives the displacement mechanism in response to an input operation on the operation unit to displace the inspection head, The ophthalmic apparatus according to claim 17, wherein the drive control unit switches to the manual control mode if the alignment detection unit does not detect the relative position while the displacement mechanism moves the inspection head for a predetermined period of time or a predetermined distance.

19. the pair of concave mirrors are a first concave mirror and a second concave mirror connected by a concave mirror bracket, the first concave mirror has a first reflecting surface facing the eye to be examined, the second concave mirror has a second reflecting surface that is partially opposed to the first reflecting surface, and that reflects the illumination light from the illumination optical system to the first reflecting surface and reflects the return light from the first reflecting surface to the imaging optical system, 16. An ophthalmic device according to claim 1, further comprising a switching mechanism that can switch the pair of concave mirrors between a first position in which the first reflecting surface is positioned in front of the left eye and the second reflecting surface is positioned on the left side of the face when the subject's eye is the left eye, and a second position in which the first reflecting surface is positioned in front of the right eye and the second reflecting surface is positioned on the right side of the face when the subject's eye is the right eye.

20. an examination head including an illumination optical system that emits illumination light to illuminate the subject's eye, and an imaging optical system that guides return light from the subject's eye illuminated with the illumination light to an imaging element; a pair of concave mirrors provided in the examination head and forming optical paths of the illumination light and the return light between the examination head and the subject's eye; a displacement mechanism that displaces the examination head relative to the eye to be examined; A method for operating an ophthalmic device comprising: A method for operating an ophthalmic device, in which an axis that is parallel to the front-to-back direction, which is the working distance direction of the examination head, and that passes through the subject's eye is defined as a reference axis, and an axis that is tilted outward from the reference axis, away from the subject's nose, with the subject's eye as the center, is defined as an inclined axis, and the displacement mechanism is driven to displace the examination head along the inclined axis to an examination position for the subject's eye.

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