Ophthalmic equipment and method of operating ophthalmic equipment

Abstract

The present invention provides an ophthalmic device and a method for operating the ophthalmic device that can reliably avoid the examination head (a pair of concave mirrors) coming into close proximity to the patient's nose. [Solution] The ophthalmic device (fundus camera 9) comprises an examination head 20, a pair of concave mirrors (concave mirror unit 50) provided on the examination head 20, a displacement mechanism (X-axis drive unit 14, Z-axis drive unit 15, Y-axis drive unit 16, swing rotation drive unit 17) for displacing the examination head 20, a drive control unit 93 that drives the displacement mechanism to displace the examination head 20 along the tilt axis TA to the examination position of the eye E under examination, a distance detection unit (stereo cameras 81L, 81R, detection control unit 93A) for detecting the face distance Fd while the examination head 20 is displaced along the tilt axis TA, and a retraction control unit 93B that drives the displacement mechanism to rotate the examination head 20 in a direction that increases the face distance Fd when the face distance Fd falls below a threshold.

Description

Technical Field

[0001] The present invention relates to an ophthalmic device including an inspection head provided with a pair of concave mirrors and a method of operating the ophthalmic device.

Background Art

[0002] In ophthalmology, ophthalmic examinations of the eye to be examined (acquisition of various eye characteristics such as the refractive power of the eye to be examined, intraocular pressure, and the number of corneal endothelial cells, fundus photography, tomographic imaging, etc.) are performed using an ophthalmic device. As one such ophthalmic device, a mirror-type fundus camera capable of wide-angle imaging of the fundus is known (see Patent Document 1). A pair of concave mirrors is provided on the front surface of the inspection head of this fundus camera. This pair of concave mirrors forms the optical path of the illumination light irradiated from the inspection head to the eye to be examined and the optical path of the return light incident from the eye to be examined to the inspection head between the inspection head and the eye to be examined.

[0003] When performing fundus photography with the fundus camera described in Patent Document 1, alignment of the inspection head with respect to the eye to be examined, that is, 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 eye to be examined is imaged with a stereo camera, and alignment detection for detecting the relative position of the inspection head with respect to the eye to be examined based on the anterior segment image obtained by this imaging is performed. Then, based on the result of this alignment detection, the inspection head is moved by an electric actuator to perform auto-alignment of the inspection head with respect to the eye to be examined.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

[0005] When performing auto-alignment of the examination head for the eye under examination 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 face of the subject, but in doing so, there is a risk that the pair of concave mirrors will come close to the nose of the subject.

[0006] This invention has been made in view of these circumstances, and aims to provide an ophthalmic device and a method for operating the ophthalmic device that can reliably avoid the examination head (a pair of concave mirrors) coming into close proximity to the nose of the patient. [Means for solving the problem]

[0007] An ophthalmic apparatus for achieving the object of the present invention comprises: an examination head comprising: an illumination optical system that emits illumination light to illuminate the eye to be examined; and an imaging optical system that guides the reflected light from the eye irradiated with illumination light to an image sensor; a pair of concave mirrors provided on the examination head that form optical paths for illumination light and reflected light between the examination head and the eye to be examined; a displacement mechanism that displaces the examination head relative to the eye to be examined; a drive control unit that drives the displacement mechanism to displace the examination head along the tilt axis to the examination position of the eye to be examined, when the reference axis is an axis parallel to the front-to-back direction which is the operating distance direction of the examination head and passing through the eye to be examined, and the tilt axis is an axis tilted outward from the reference axis with the eye to the center to move away from the nose of the person being examined; a distance detection unit that detects the face distance, which is the distance between the examination head and the face of the person being examined, while the examination head is being displaced along the tilt axis by the displacement mechanism; and a retraction control unit that drives the displacement mechanism to rotate the examination head in a direction that increases the face distance around a predetermined rotation axis when the face distance detected by the distance detection unit falls below a predetermined threshold.

[0008] This ophthalmic device allows for the avoidance of close proximity between the examination head (a pair of concave mirrors) and the patient's face by driving a rotation mechanism to rotate the examination head when the distance detected by the distance detection unit falls below a predetermined threshold.

[0009] In another aspect of the present invention, an ophthalmic device detects the distance between the examination head and the patient's nose as the facial distance. This makes it possible to avoid the examination head coming too close to the patient's nose.

[0010] In another aspect of the present invention, the ophthalmic apparatus includes a displacement mechanism that moves the examination head in the forward / backward, left / right, and up / down directions relative to the eye being examined, and a rotation mechanism that rotates the examination head about a rotation axis, and the retraction control unit performs a first retraction control that drives the rotation mechanism to rotate the examination head in a direction that increases the distance from the face, and a second retraction control that stops the drive of the movement mechanism or drives the movement mechanism to retract the examination head in a direction that moves it away from the face. This makes it possible to avoid the examination head coming into close proximity to the face of the person being examined.

[0011] In another aspect of the present invention, the ophthalmic apparatus includes a displacement mechanism that moves the examination head in the forward / backward, left / right, and up / down directions relative to the eye under examination, and a rotation mechanism that rotates the examination head about a rotation axis, wherein the rotation axis is provided below the examination head, and the movement mechanism moves the examination head and the rotation axis together in the forward / backward, left / right, and up / down directions. This allows the examination head to be arbitrarily displaced relative to the eye under examination.

[0012] In another aspect of the present invention, the axis of rotation is parallel to the vertical direction and the outward direction is parallel to the left-right direction.

[0013] In another aspect of the present invention, the ophthalmic apparatus is perpendicular to the vertical direction, and the outward direction is upward in the vertical direction.

[0014] In another aspect of the present invention, the ophthalmic apparatus includes a displacement mechanism that moves the examination head in the front-to-back, left-to-right, and up-and-down directions relative to the eye under examination, and a rotation mechanism that rotates the examination head about a rotation axis, wherein the rotation axis is located on the front side in the front-to-back direction, closer to the eye under examination than the examination head, and the movement mechanism moves the examination head and the rotation axis together in the front-to-back, left-to-right, and up-and-down directions. This makes it possible to arbitrarily displace the examination head relative to the eye under examination.

[0015] In another aspect of the present invention, the axis of rotation is parallel to the vertical direction and the outward direction is parallel to the left-right direction.

[0016] In another aspect of the present invention, the ophthalmic apparatus is perpendicular to the vertical direction, and the outward direction is upward in the vertical direction.

[0017] In another aspect of the present invention, the ophthalmic apparatus includes a distance detection unit comprising: a plurality of cameras provided on an examination head; a detection control unit that repeatedly performs: a shooting control that causes the plurality of cameras to photograph the face from multiple different directions while the examination head is displaced along the tilt axis by a displacement mechanism; and a calculation of the face distance based on the face images captured by each of the plurality of cameras. This makes it possible to continuously detect the face distance while the examination head is displaced along the tilt axis by the displacement mechanism.

[0018] In another aspect of the present invention, the ophthalmic apparatus includes a distance detection unit comprising: a plurality of cameras provided on an examination head; a pre-imaging control unit that causes one specific camera capable of capturing the nose among the plurality of cameras to capture the nose at the initial position of the examination head; and a detection control unit that repeatedly performs imaging control to capture the nose with the specific camera while the examination head is displaced along the tilt axis by a displacement mechanism, and calculation processing to calculate the face distance by comparing a newly captured image of the nose by the specific camera with an image of the nose captured at the initial position. As a result, even if only one camera (specific camera) is capable of capturing the nose while the examination head is displaced along the tilt axis by the displacement mechanism, the face distance can be continuously detected.

[0019] In another aspect of the present invention, the ophthalmic apparatus includes a distance detection unit comprising a non-contact distance measuring sensor provided on the examination head, and a detection control unit that repeatedly calculates the face distance based on the detection signal output from the distance measuring sensor while the examination head is being displaced along the tilt axis by a displacement mechanism. This makes it possible to continuously detect the face distance while the examination head is being displaced along the tilt axis by the displacement mechanism.

[0020] In another aspect of the present invention, the ophthalmic apparatus comprises a pair of concave mirrors, a first concave mirror and a second concave mirror connected by a concave mirror bracket, wherein the first concave mirror has a first reflective surface facing the eye under examination, and the second concave mirror has a second reflective surface that partially faces the first reflective surface and reflects illumination light from the illumination optical system to the first reflective surface, and reflects the reflected light from the first reflective surface to the imaging optical system, and the pair of concave mirrors is equipped with a switching mechanism that allows switching between a first position in which the first reflective surface is positioned in front of the left eye and the second reflective surface is positioned on the left side of the face when the eye under examination is the left eye, and a second position in which the first reflective surface is positioned in front of the right eye and the second reflective surface is positioned on the right side of the face when the eye under examination is the right eye. This enables wide-angle imaging of the observed portion of the eye under examination.

[0021] A method of operating an ophthalmic apparatus for achieving the object of the present invention includes an illumination optical system that emits illumination light for illuminating an eye to be examined, and an imaging optical system that guides return light from the eye to be examined irradiated with the illumination light to an imaging device. The method further includes an inspection head provided with a pair of concave mirrors that form optical paths of the illumination light and the return light between the inspection head and the eye to be examined, and a displacement mechanism that displaces the inspection head with respect to the eye to be examined. In the method of operating the ophthalmic apparatus, with a direction parallel to the front-rear direction, which is the operating distance direction of the inspection head, and an axis passing through the eye to be examined as a reference axis, and with an axis obtained by inclining the reference axis outward away from the nose of the subject around the eye to be examined as an inclination axis, a drive control step of driving the displacement mechanism to displace the inspection head along the inclination axis to an inspection position of the eye to be examined, a distance detection step of detecting a face distance, which is a distance between the inspection head and the face of the subject, while the inspection head is being displaced along the inclination axis by the displacement mechanism, and a retraction control step of driving the displacement mechanism to rotate the inspection head in a direction in which the face distance increases around a predetermined rotation axis when the face distance detected in the distance detection step becomes less than a predetermined threshold value.

Advantages of the Invention

[0022] The present invention can surely avoid the inspection head (pair of concave mirrors) from approaching the nose of the subject.

Brief Description of the Drawings

[0023] [Figure 1] It is an external perspective view of the fundus camera according to the first embodiment. [Figure 2] It is a side view of the fundus camera according to the first embodiment. [Figure 3] It is a front view of the fundus camera according to the first embodiment as seen from the subject side. [Figure 4] It is a top view of the concave mirror unit rotated to the first position during fundus imaging of the left eye. [Figure 5] It is a top view of the concave mirror unit rotated to the second position during fundus imaging of the right eye. [Figure 6] It is a top view of the imaging optical system of the inspection head. [Figure 7]This is a side view of the illumination optical system of the inspection head. [Figure 8] This is a front view of the illumination optical system and alignment optical system of the inspection head. [Figure 9] This is a perspective view of the facial support area from the subject's side. [Figure 10] This is a functional block diagram of the control unit. [Figure 11] This is an explanatory diagram illustrating the method for auto-aligning the inspection head. [Figure 12] This is an explanatory diagram illustrating a first-first example of auto-alignment of the inspection head in the first embodiment. [Figure 13] This is an explanatory diagram illustrating the first and second examples of auto-alignment of the inspection head in the first embodiment. [Figure 14] This is an explanatory diagram illustrating the first to third examples of auto-alignment of the inspection head in the first embodiment. [Figure 15] This is an explanatory diagram illustrating the possibility of the examination head being in close proximity to the subject's face (especially the nose) during auto-alignment. [Figure 16] This is an explanatory diagram illustrating the retraction control of the inspection head in the first embodiment. [Figure 17] This is an explanatory diagram illustrating a modified example of the retraction control of the inspection head according to the first embodiment. [Figure 18] This is a flowchart showing the process of photographing the fundus of the eye being examined using the fundus camera of the first embodiment. [Figure 19] This is a flowchart illustrating the auto-alignment process for the inspection head. [Figure 20] This is an explanatory diagram illustrating the displacement of the inspection head after the auto-alignment process has started. [Figure 21] This is a side view of the main part of the fundus camera of the second embodiment. [Figure 22] This is an explanatory diagram illustrating a second-first example of auto-alignment of the inspection head in the second embodiment. [Figure 23]This is an explanatory diagram illustrating a second example of auto-alignment of the inspection head in the second embodiment. [Figure 24] This is an explanatory diagram illustrating an example of the retraction control of the inspection head in the second embodiment. [Figure 25] This is a side view of the main part of the fundus camera of the third embodiment. [Figure 26] This is an explanatory diagram illustrating a third example of auto-alignment of the inspection head in the third embodiment. [Figure 27] This is an explanatory diagram illustrating a fourth example of auto-alignment of the inspection head in the fourth embodiment. [Figure 28] This is a front view of the examination head of the fundus camera according to the fifth embodiment. [Modes for carrying out the invention]

[0024] [First Embodiment] <Overall configuration of the fundus camera> Figure 1 is an external perspective view of the fundus camera 9 of the first embodiment. Figure 2 is a side view of the fundus camera 9 of the first embodiment. Figure 3 is a front view of the fundus camera 9 of the first embodiment as seen from the subject H side. In the figures, the X-axis direction is the left-right direction with respect to the subject H, the Y-axis direction is the up-down direction, and the Z-axis direction is the front-back direction (also called the working distance direction) parallel to the forward direction towards the subject H (eye E) and the backward direction away from the subject H.

[0025] As shown in Figures 1 to 3, the fundus camera 9 corresponds to the ophthalmic device of the present invention and comprises a device 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, an imaging optical system 60, an illumination optical system 70, an alignment optical system 80, and a control device 90.

[0026] The device stand 10 is a base member that is placed on an optical table T whose height can be adjusted in the Y-axis direction. A face support part 30 is fixed to the front end of the device stand 10 on the Z-axis forward side (subject H side), and a control panel 40 is attached to the rear end of the device stand 10 on the Z-axis rear side (examiner side). In addition, an examination head 20 is positioned in the central area of ​​the device stand 10, sandwiched between the face support part 30 and the control panel 40.

[0027] An X-axis movable frame 11, which is movable in the X-axis direction relative to the device frame 10, is positioned in the central region of the device frame 10. A Z-axis movable frame 12, which is movable in the Z-axis direction relative to the X-axis movable frame 11, is positioned on the X-axis movable frame 11. A Y-axis movable frame 13, which is movable in the Y-axis direction relative to the Z-axis movable frame 12, is positioned on the Z-axis movable frame 12. The device frame 10 has an X-axis drive unit 14 that moves the X-axis movable frame 11 in the X-axis direction. The X-axis movable frame 11 has a Z-axis drive unit 15 that moves the Z-axis movable frame 12 in the Z-axis direction. The Z-axis movable frame 12 has a Y-axis drive unit 16 that moves the Y-axis movable frame 13 in the Y-axis direction. The X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16 constitute the movement mechanism of the present invention, and for example, a motor actuator is used.

[0028] The inspection head 20 is equipped with a concave mirror unit 50, an imaging optical system 60, an illumination optical system 70, and an alignment optical system 80. The inspection head 20 is mounted on a Y-axis movable frame 13. As a result, the inspection head 20 can move in the XYZ 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.

[0029] 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, Z-axis drive unit 15, and Y-axis drive unit 16 described above, constitute the displacement mechanism of the present invention.

[0030] 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 located on the lower side of the inspection head 20 in the Y-axis direction and moves and rotates together with the inspection head 20 in the XYZ axis directions.

[0031] Thus, the inspection head 20 is movable in the XYZ directions by the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16, and is also rotatable around the axis 21 centered by the swing rotation drive unit 17. This allows the inspection head 20 to be moved linearly in each axial direction, rotated around the rotation axis 21, or move in a trajectory that combines linear and rotational movement during auto-alignment and left / right eye switching.

[0032] The face support section 30 is provided at the front end of the device stand 10 and is located forward in the Z-axis direction from the concave mirror unit 50. The face support section 30 supports the forehead and chin of the subject H in order to stabilize the position and orientation of the eye E being examined. The face support section 30 includes a main body section 31, a forehead support frame 32 that contacts the forehead of the subject H, a chin support base 33 that contacts the chin of the subject H, a lifting rod 34 parallel to the Y-axis direction, and a chin support drive unit 35.

[0033] The jaw rest drive unit 35 is built into the main body 31 and drives the lifting rod 34 in the Y-axis direction. The jaw rest drive unit 35 is composed of, for example, a motor and a motor drive circuit. A jaw rest base 33 is provided at the upper end of the lifting rod 34, and the Y-axis position of the jaw rest base 33 can be adjusted by driving the lifting rod 34 in the Y-axis direction by the jaw rest drive unit 35.

[0034] The control panel 40 is located at the rear end of the device stand 10. This control panel 40 has a touch panel screen 41 that displays in color images of the fundus of the eye E taken by the imaging optical system 60 and images of the anterior segment of the eye E taken by the alignment optical system 80 (stereo cameras 81L, 81R shown in Figure 8 below).

[0035] The touch panel screen 41 receives touch input from the examiner on various images displayed on the screen (operation button images, anterior segment images, fundus images, etc.) and outputs operation signals to the control device 90. Therefore, the control panel 40 (touch panel screen 41) functions as an operation unit. A known tablet terminal may be used instead of the control panel 40. In addition, various known operation units and display units other than the control panel 40 may be used.

[0036] The control panel 40 is used for adjusting the position of the chin rest 33, moving the examination head 20 in the XYZ axis directions, rotating the examination head 20, switching between auto-alignment and manual alignment, starting the examination, and saving the examination results (fundus image).

[0037] The concave mirror unit 50 consists of a first concave mirror 51 and a second concave mirror 52, which correspond to the 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. This concave mirror unit 50 is rotatably held at a position on the front side of the inspection head 20 by a unit rotation drive unit 55 provided on the inspection head 20, and faces the face support unit 30 (the face of the subject H).

[0038] 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 includes, for example, a motor, a timing belt stretched across two pulleys, and a motor drive circuit. When the eye E under examination is the left eye, the concave mirror unit 50 is switched by the unit rotation drive unit 55 to the first position described later (see Figure 4), and when the eye E under examination is the right eye, the unit rotation drive unit 55 is switched to the second position described later (see Figure 5).

[0039] The imaging optical system 60 is located on the upper side of the inspection head 20. The illumination optical system 70 is located on the lower side of the inspection head 20. The alignment optical systems 80 are located on the left and right sides of the lower front end of the inspection head 20.

[0040] The control device 90 controls various parts of the fundus camera 9 (face support unit 30, concave mirror unit 50, imaging optical system 60, illumination optical system 70, alignment optical system 80, etc.) based on input operations, including touch operations on the control panel 40 (touch panel screen 41). This control device 90 is installed on the examination head 20 and, for example, has a hardware configuration that includes a main board, a TRC (Time Ratio Control) control board, and a galvanometer driver board.

[0041] <Detailed configuration of the concave mirror unit> Figure 4 is a top view of the concave mirror unit 50 rotated to the first position during fundus photography of the left eye. Figure 5 is a top view of the concave mirror unit 50 rotated to the second position during fundus photography of the right eye. In the figures, the symbol CL represents the central axis of the examination head 20. This central axis CL coincides with (approximately coincides with, and the same applies hereafter) the unit rotation axis 54 when the examination head 20 is viewed from one direction in the Y-axis direction.

[0042] As shown in Figures 4 and 5, the concave mirror unit 50 is rotatably held by the unit rotation drive unit 55 at a position between the eye E under examination and the front surface of the examination head 20 (the dichroic mirrors 57L and 57R shown in Figure 6, which will be described later). The first concave mirror 51 and the second concave mirror 52, which constitute the concave mirror unit 50, form a reflected light path for illumination light from the illumination optical system 70 to the fundus of the eye E under examination, and a reflected light path for return light from the fundus of the eye E under examination to the imaging optical system 60.

[0043] The first concave mirror 51 has a first reflective surface 51a formed thereon, which has two optically conjugate focal points F1 and F2. The position of focal point F1 is the position where the pupil of the eye under examination E is positioned when observing and photographing the fundus of the eye under examination E.

[0044] The second concave mirror 52 has a second reflective surface 52a formed thereon, which has two optically conjugate foci F3 and F4. This second reflective surface 52a partially faces the first reflective surface 51a. The position of focal spot F3 is the same as the position of focal spot F2. The position of focal spot F4 is the position of the optical path branching point between the optical path of the imaging optical system 60 and the optical path of the illumination optical system 70.

[0045] The concave mirror bracket 53 connects the first concave mirror 51 and the second concave mirror 52 while maintaining the relative positions of the focal points F1 to F4. The unit rotation shaft 54 ​​of the unit rotation drive unit 55 is connected to this concave mirror bracket 53.

[0046] The concave mirror unit 50 is rotatable (swivelable) to a first position when the eye E being examined is the left eye (see Figure 4) and to a second position when the eye E being examined is the right eye (see Figure 5). By rotating this concave mirror unit 50 with the unit rotation drive unit 55, the concave mirror unit 50 is configured to be usable for both the left and right eyes.

[0047] The "first position" is a horizontal arrangement where the first concave mirror 51 is positioned in front of the left eye and the second concave mirror 52 is positioned on the left side of the face, as shown in Figure 4. The "second position" is a horizontal arrangement where the first concave mirror 51 is positioned in front of the right eye and the second concave mirror 52 is positioned on the right side of the face, as shown in Figure 5. In addition to the first and second positions, the concave mirror unit 50 also has a reference position, which is a vertical arrangement where the first concave mirror 51 is in the lower position and the second concave mirror 52 is in the upper position in the Y-axis direction, as shown in Figure 2 described above.

[0048] When performing fundus photography of the left eye, the examination head 20 is positioned towards the left end of the device stand 10 as viewed from the subject H side, and is tilted at an angle with respect to the central axis CL relative to the Z-axis, as shown in Figure 4. When performing fundus photography of the right eye, the examination head 20 is positioned towards the right end of the device stand 10 as viewed from the subject H side, and is tilted at an angle with respect to the central axis CL relative to the Z-axis, as shown in Figure 5.

[0049] Furthermore, the examination head 20 is positioned in its initial position before the start of fundus photography. This initial position is the central position of the device stand 10 in the X-axis direction (the central position of the movable range of the examination head 20 in the X-axis direction), and is a retracted position that is moved backward (separated) from the subject H in the Z-axis direction (see symbol XIIA in Figure 12).

[0050] <Detailed configuration of the imaging optical system> Figure 6 is a top view of the imaging optical system 60 of the inspection head 20. Figure 7 is a side view of the illumination optical system 70 of the inspection head 20. Figure 8 is a front view of the illumination optical system 70 and alignment optical system 80 of the inspection head 20.

[0051] As shown in Figures 6 to 8, the imaging optical system 60 includes a left-eye imaging optical system 60L for left eye fundus imaging and a right-eye imaging optical system 60R for right eye fundus imaging (see Figure 6). The illumination optical system 70 is provided independently along the central axis CL of the examination head 20 (see Figure 7). The alignment optical system 80 includes a left-eye alignment optical system 80L used for auto-alignment before left eye fundus imaging and a right-eye alignment optical system 80R used for auto-alignment before right eye fundus imaging (see Figure 8).

[0052] The imaging optical system 60 and the illumination optical system 70 employ a separated illumination method in which the observation light beam and the illumination light beam are offset within the pupil circle of the eye E under examination. In addition, dichroic mirrors 57L and 57R are placed at the optical path branching points of each optical system to merge the observation light path, illumination light path, and alignment light path. If a coaxial illumination method is adopted instead of the separated illumination method in which the observation light beam and illumination light beam are aligned within the pupil circle as described above, a perforated mirror may be placed at the optical path branching point.

[0053] As shown in Figure 6, the imaging optical system 60 images the reflected light from the fundus of the eye E that has been incident via the concave mirror unit 50. This imaging optical system 60 comprises an imaging optical system 60L for the left eye and an imaging optical system 60R for the right eye, a slide plate 68, and a focusing drive unit 69.

[0054] The left-eye imaging optical system 60L and the right-eye imaging optical system 60R have a symmetrical structure with respect to the central axis CL on the upper surface of the examination head 20. Furthermore, the left-eye imaging optical system 60L and the right-eye imaging optical system 60R are eccentric optical systems with eccentric optical paths.

[0055] The left eye imaging optical system 60L includes a dichroic mirror 57L arranged along the optical path of the reflected light indicated by the arrow in the figure, an imaging aperture 600L, a first reflective mirror 61L, a first lens unit 62L, a second reflective mirror 63L, a second lens unit 64L, a focusing lens 65L, a third lens unit 66L, and an imaging unit 67L. The imaging aperture 600L is positioned conjugate to the pupil of the eye under examination E. In the imaging unit 67L, a fundus image sensor 671L (corresponding to the image sensor of the present invention) is positioned at an outward-facing inclination angle in a plan view, in accordance with the setting of the eccentric optical system. The fundus image sensor 671L is positioned conjugate to the fundus of the eye under examination E.

[0056] The imaging optical system 60R for the right eye includes a dichroic mirror 57R arranged along the optical path of the reflected light indicated by the arrow in the figure, an imaging aperture 600R, a first reflective mirror 61R, a first lens unit 62R, a second reflective mirror 63R, a second lens unit 64R, a focusing lens 65R, a third lens unit 66R, and an imaging unit 67R. The imaging aperture 600R is positioned conjugate to the pupil of the eye under examination E. In the imaging unit 67R, a fundus image sensor 671R (corresponding to the image sensor of the present invention) is positioned at an inclination angle that is outwardly open in a plan view, in accordance with the setting of the eccentric optical system. The fundus image sensor 671R is positioned conjugate to the fundus of the eye under examination E.

[0057] The slide plate 68 is provided on the upper surface of the inspection head 20 so as to be movable in a direction along the central axis CL (in the Z-axis direction in the figure). The upper surface of the slide plate 68 is provided with second lens units 64L, 64R, focusing lenses 65L, 65R, and third lens units 66L, 66R.

[0058] The focusing drive unit 69 is, for example, a motor actuator, and performs focusing control to adjust the focus of the imaging optical system 60 to the fundus of the eye E by displacing the slide plate 68 in a direction along the central axis CL when the fundus of the eye E is being photographed.

[0059] <Detailed configuration of the illumination optical system> As shown in Figures 7 and 8, the illumination optical system 70 projects slit scan light, which is illumination light, onto the fundus of the eye E being examined via a concave mirror unit 50. This illumination optical system 70 includes a light source unit 71, a slit unit 72, a galvanometer scanner 73 (optical scanner), a first reflection mirror 741, a second reflection mirror 742, a left / right switching mirror 75, and dichroic mirrors 57L and 57R, all arranged along the illumination light path shown in the figures.

[0060] The optical path from the left / right switching mirror 75 to the dichroic mirror 57L includes the first lens unit 761L, the third reflective mirror 763L, and the second lens unit 762L shown in Figure 8, and the fourth reflective mirror 744L shown in Figure 7. Furthermore, the optical path from the left / right switching mirror 75 to the dichroic mirror 57R includes the first lens unit 761R, the third reflective mirror 763R, and the second lens unit 762R shown in Figure 8, and the fourth reflective mirror 744R shown in Figure 7.

[0061] The light source unit 71 emits illumination light toward the slit unit 72. This light source unit 71 has an iris diaphragm 71a located near the slit unit 72. The iris diaphragm 71a is positioned conjugate to the pupil of the eye E being examined.

[0062] The slit unit 72 includes a slit 72a and a projection lens 72b. The slit 72a is positioned conjugate to the fundus of the eye E being examined. This causes a slit-shaped illumination light (slit light) to be shone onto the fundus of the eye E being examined. The slit unit 72 is also provided with a slit drive unit 77. The slit drive unit 77 has a linear motion part that adjusts the focus of the slit 72a to match the eye E being examined.

[0063] The galvanoscanner 73 scans the illumination light (slit light) shining onto the fundus of the eye E being examined. The scanner drive unit 78 controls the drive of the galvanoscanner 73 (scan angle of the slit light).

[0064] The left / right switching mirror 75 is located on the lower side of the unit rotation axis 54 in the Y-axis direction and is rotatable around a mirror rotation axis 75a (see Figure 8) 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.

[0065] Furthermore, the illumination optical system 70 may be provided with a fixation light projection system 770 (see Figure 10) that projects fixation light onto the fundus of the eye E to cause the eye E to fixate.

[0066] <Detailed configuration of the alignment optical system> As shown in Figure 8, the alignment optical system 80 is provided at the left and right positions of the front end of the examination head 20. The alignment optical system 80 acquires an anterior segment image of the eye under examination E when performing auto-alignment, which adjusts the position of the eye under examination E to the position of the first focal point F1 of the first concave mirror 51. The alignment optical system 80 includes 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.

[0067] An alignment optical frame 22L is fixed to the lower Y-axis side of the dichroic mirror 57L in the examination head 20, and a left-eye alignment optical system 80L is provided in this alignment optical frame 22L. The left-eye alignment optical system 80L has a stereo camera 81L and an alignment illumination lamp 82L positioned on the lower Y-axis side of the dichroic mirror 57L. The alignment illumination lamp 82L illuminates the left eye, which is the eye under examination E, with illumination light via the dichroic mirror 57L. The stereo camera 81L has an anterior segment image sensor and stereographs the left eye, which is illuminated with illumination light via the dichroic mirror 57L, and outputs an anterior segment image of this left eye.

[0068] An alignment optical frame 22R is fixed to the lower Y-axis side of the dichroic mirror 57R in the examination head 20, and a right-eye alignment optical system 80R is provided in this alignment optical frame 22R. The right-eye alignment optical system 80R has a stereo camera 81R and an alignment illumination lamp 82R located on the lower Y-axis side of the dichroic mirror 57R. The alignment illumination lamp 82R illuminates the right eye, which is the eye under examination E, with illumination light via the dichroic mirror 57R. The stereo camera 81R has an anterior segment image sensor and stereographs the right eye, which is illuminated with illumination light via the dichroic mirror 57R, and outputs an anterior segment image of the right eye.

[0069] <Detailed configuration of the face support section> Figure 9 is a perspective view of the face support unit 30 from the subject H's side. As shown in Figure 9, the face support unit 30 supports the subject H's face in different positions and postures when taking fundus images of the left eye and when taking fundus images of the right eye (see Figures 4 and 5).

[0070] The forehead support frame 32 has a left-eye forehead support surface 32a that the subject H's forehead rests against during left-eye fundus photography, and a right-eye forehead support surface 32b that the subject H's forehead rests against during right-eye fundus photography. The left-eye forehead support surface 32a and the right-eye forehead support surface 32b are made of silicone rubber or the like.

[0071] The chin rest 33 has a left-eye chin rest surface 33a that supports the subject H's chin when the left eye is being photographed, and a right-eye chin rest surface 33b that supports the subject H's chin when the right eye is being photographed. The left-eye chin rest surface 33a and the right-eye chin rest surface 33b are each concave curved surfaces corresponding to the shape of the chin, and are formed on the chin rest 33 in such a way that they partially overlap each other.

[0072] <Control device detailed configuration> Figure 10 is a functional block diagram of the control device 90. As shown in Figure 10, in addition to the parts 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.

[0073] The image forming unit 120 forms a fundus image of the eye under examination 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, on the fundus image of the eye under examination E formed by the image forming unit 120.

[0074] The memory unit 131 is a recording medium (storage medium) that stores the program executed by the control device 90, and various known storage devices are used. The memory unit 131 also stores the fundus image of the eye E under examination.

[0075] The control device 90 includes an arithmetic circuit composed of various processors and memory. These processors include CPUs (Central Processing Units), GPUs (Graphics Processing Units), ASICs (Application Specific Integrated Circuits), and programmable logic devices [e.g., SPLDs (Simple Programmable Logic Devices), CPLDs (Complex Programmable Logic Devices), and FPGAs (Field Programmable Gate Arrays)]. The various functions of the control device 90 may be implemented by a single processor, or by multiple processors of the same or different types.

[0076] The control device 90 functions as a tilt angle determination unit 91, alignment detection unit 92, drive control unit 93, detection control unit 93A, retraction control unit 93B, fixation control unit 94, fundus imaging control unit 95, and storage control unit 96 by executing the control program stored in the memory unit 131.

[0077] Each component of the control device 90 functions during the auto-alignment of the inspection head 20. Therefore, the method of auto-aligning the inspection head 20 will first be explained with reference to Figure 11. In Figure 11, the symbol "OS" indicates the left eye (Oculus Sinister), and the symbol "OD" indicates the right eye (Oculus Dexter). As shown by the symbol XIA in Figure 11, when the inspection head 20 is moved forward in the Z-axis direction from the frontal position of the eye E (in this case, the left eye OS) during auto-alignment, there is a risk that the inspection head 20 (first concave mirror 51) will come into close proximity to the nose N of the subject H.

[0078] Therefore, as shown by reference numeral XIB in Figure 11, in the fundus camera 9 of this embodiment, when the examination head 20 is auto-aligned, the examination head 20 is approached from an oblique direction when viewed from one direction in the Y-axis direction (for example, the upper side in the Y-axis direction).

[0079] Specifically, the reference axis VA is defined as an axis parallel to the Z-axis and passing through the eye under examination E (for example, its center). The outward direction X1 is defined as the direction away from the nose N with respect to the eye under examination E (in this case, the left eye OS) in the X-axis direction. The tilt axis TA is defined as the axis obtained by tilting the reference axis VA outward by an angle θ with respect to the eye under examination E as the center. The examination head 20 is then displaced along the tilt axis TA to an examination position (hereinafter simply referred to as the examination position) where fundus photography of the eye under examination E can be performed when viewed from above in the Y-axis direction. "Displacement" here includes movement and rotation of the examination head 20 in the XYZ axis directions.

[0080] Returning to Figure 10, the tilt angle determination unit 91 determines the tilt angle θ of the tilt axis TA with respect to the reference axis VA in the XZ plane. For example, the tilt angle determination unit 91 determines the tilt angle θ as a value selected by the examiner on the control panel 40 from among several angles (10°, 15°, 20°, etc.), and outputs this tilt angle θ information to the drive control unit 93.

[0081] Alternatively, the tilt angle determination unit 91 may detect the relative position of the nose N with respect to the inspection head 20 based on the captured image obtained by stereo imaging the nose N with one of the stereo cameras 81L or 81R, and determine a tilt angle θ that avoids the inspection head 20 (first concave mirror 51) coming too close to the nose N based on this detection result. Here, "one of the stereo cameras 81L or 81R" refers to stereo camera 81L when photographing the fundus of the left eye OS, and stereo camera 81R when photographing the fundus of the right eye OD (the same applies hereafter).

[0082] During the auto-alignment of the examination head 20, the alignment detection unit 92 detects the relative position of the eye E with respect to the examination head 20 by determining the pupil center position of the eye E and calculating the three-dimensional coordinates of this pupil center position, based on the anterior segment image of the eye E stereo-captured by one of the stereo cameras 81L or 81R. Since the method of alignment detection using stereo cameras 81L and 81R is a known technique (see Patent Document 2 above), a detailed explanation is omitted here.

[0083] The drive control unit 93 controls the drive of each drive unit 14-17, 35, 55, 69, 77-79 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 eye to be examined E, and to switch the eye to be examined (switching between left and right eyes). In addition, 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 left eye OS) or the second position (when photographing the right eye OD).

[0084] The 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 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 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 the inspector's input operation to the control panel 40. Switching between auto-alignment and manual alignment is performed on the control panel 40.

[0085] During auto-alignment, the drive control unit 93 determines the tilt axis TA corresponding to the tilt angle θ initially determined by the tilt angle determination unit 91.

[0086] For example, the drive control unit 93 first stereo-captures the face of the subject H (such as the eye E or nose N) using one of the stereo cameras 81L or 81R and determines the reference axis VA based on the captured image. Alternatively, the drive control unit 93 estimates the reference axis VA based on the Y-axis position of the chin rest 33 and known discrimination information for the left eye OS and right eye OD. Then, the drive control unit 93 determines the tilt axis TA as an axis tilted by an angle θ in the outward direction X1 of the reference axis VA, with the eye E as the center.

[0087] 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 inspection head 20 from the initial position when the fundus camera 9 is powered on to the inspection position.

[0088] Figure 12 is an explanatory diagram illustrating a first example of auto-alignment of the inspection head 20 in the first embodiment. As indicated by the reference numeral XIIA in Figure 12, in its initial position, the inspection head 20 is located at the center of its movable range in the X-axis direction (including the approximate center position or the position facing the face support portion 30) and at a retracted position in the Z-axis direction, moved backward in the Z-axis direction from the subject H. When the inspection head 20 is in its initial position, the central axis CL of the inspection head 20 coincides with the aforementioned center position when viewed from above in the Y-axis direction.

[0089] First, the drive control unit 93 drives the X-axis drive unit 14 to perform a first drive process that moves the inspection head 20 outward in the X1 direction from its initial position to the inclination axis TA when viewed from above in the Y-axis direction.

[0090] As shown by the symbol XIIB in Figure 12, the drive control unit 93 drives the swing rotation drive unit 17 after the completion of the first drive process to perform a second drive process that rotates the inspection head 20 by an inclination angle θ around the rotation axis 21 (see arrow R). As a result, as shown by the symbol XIIC in Figure 12, the central axis CL of the inspection head 20 becomes parallel to the inclination axis TA. Note that the second drive process may be performed before the first drive process.

[0091] Next, after the completion of the second drive process, 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 that moves 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). As a result, the inspection head 20 is moved toward the eye E to be examined while maintaining a constant tilt angle θ (including approximately constant, the same applies hereinafter).

[0092] During this auto-alignment process, the inspection head 20 is displaced to a position where 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, based on the stereo camera 81L capturing an anterior segment image of the left eye OS. As a result, the alignment detection result is input from the alignment detection unit 92 to the drive control unit 93. In addition, to enable alignment detection by the alignment detection unit 92, the Y-axis drive unit 16 may perform Y-axis position adjustment of the inspection head 20 before alignment detection (at any stage from the first to the third drive process).

[0093] As shown by the symbol XIID in Figure 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 this third drive process performed based on the alignment detection result, the position of the inspection head 20 in the Y-axis direction is also adjusted.

[0094] Figure 13 is an explanatory diagram illustrating the first and second examples 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 a predetermined distance forward in the Z-axis direction (towards the subject H) as shown by the numeral XIIIA in Figure 13 (see arrow Z1), and then executes a first drive process to move the inspection head 20 outward in the inclination axis TA as shown by the numeral XIIIB in Figure 13. The distance the inspection head 20 moves forward in the Z-axis direction is not particularly limited as long as a safe distance can be secured 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 the captured image obtained by stereo imaging of the nose N with the stereo camera 81L, and the movement distance may be determined based on this calculation result.

[0095] By first moving the inspection head 20 forward in the Z-axis direction and then moving it outward in the X1 direction to the inclination axis TA, the distance the inspection head 20 needs to travel outward in the X1 direction can be reduced compared to the example 1-1 shown in Figure 12 described above.

[0096] As shown by the symbol XIIIC in Figure 13, the drive control unit 93 drives the swing rotation drive unit 17 after the completion of the first drive process and performs a second drive process similar to the first example described above (see symbol XIIB in Figure 12) to make the central axis CL parallel to the tilt axis TA. In the first example as well, the second drive process may be performed before the first drive process.

[0097] As shown by the symbol XIIID in Figure 13, after the completion of the second drive process, the drive control unit 93 drives the X-axis drive unit 14 and the Z-axis drive unit 15 to perform the third drive process in the same manner as in the previously described 1-1 example (see symbols XIIC and XIID in Figure 12), thereby moving the inspection head 20 to the inspection position along the inclination axis TA when viewed from above in the Y-axis direction. Then, as shown by the symbol XIIIE in Figure 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 result detected by the alignment detection unit 92 during the auto-alignment process, and continues the third drive process until the inspection head 20 reaches the inspection position.

[0098] Figure 14 is an explanatory diagram illustrating the first to third examples of auto-alignment of the inspection head 20 in the first embodiment. As shown by the labels XIVA and XIVB in Figure 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 perform 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 by an inclination angle θ (see arrows XZ2 and R). This allows the inspection head 20 to be moved diagonally to the inclination axis TA when viewed from above in the Y-axis direction, and the central axis CL to be parallel to the inclination axis TA.

[0099] In the first drive process of the first to third examples, the inspection head 20 may be displaced along the tilt axis TA by the shortest distance to a position where the stereo camera 81L can capture images of the anterior segment of the left eye OS.

[0100] As shown by the symbol XIVC in Figure 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 after the completion of the first drive process to execute the second drive process. The second drive process in the first to third examples is the same as the third drive process in the previously described "first to first example" and "first to second example," and moves the inspection head 20 to the inspection position along the inclination axis TA when viewed from above in the Y-axis direction. Then, as shown by the symbol XIVD in Figure 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 result 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.

[0101] In the above examples 1-1 to 1-3 of the auto-alignment process, the auto-alignment of the examination head 20 for the left eye OS was used as an example; however, the auto-alignment of the examination head 20 for the right eye OD can be performed in the same manner.

[0102] Returning to Figure 10, once fundus photography of the eye E by the imaging optical system 60 is complete, the drive control unit 93 drives the Z-axis drive unit 15 to retract the examination head 20 by a predetermined distance to the rear (examiner side) in the Z-axis direction (see symbols XXD and XXG in Figure 20, described later). Furthermore, under the control of the retraction control unit 93B, described later, if there is a risk that the examination head 20 will come into close proximity to the face of the subject H, the drive control unit 93 drives at least the swing rotation drive unit 17 to retract the examination head 20 away from the face (especially the nose N) of the subject H.

[0103] Figure 15 is an explanatory diagram illustrating the possibility of the inspection head 20 approaching the face (particularly the nose N) of the subject H during auto-alignment. As indicated by the symbol XVA in Figure 15, during auto-alignment, the inspection head 20 is displaced along the tilt axis TA to the examination position of the subject eye E (see arrow XZ1 in the figure), that is, it is brought close to the subject eye E. At this time, depending on the movement of the subject H's face or the size and shape of the nose N, the inspection head 20 may come into close proximity to the subject H's face, particularly the nose N, as shown by the symbol XVB in Figure 15. Therefore, in this embodiment, if there is a risk of the inspection head 20 coming into close proximity to the subject H's face (nose N) while the inspection head 20 is being displaced along the tilt axis TA to the examination position of the subject eye E, a retraction control is performed to move the inspection head 20 away from the subject H's face.

[0104] Figure 16 is an explanatory diagram illustrating the retraction control of the inspection head 20 in the first embodiment. As shown in Figure 16 and the previously described Figure 10, the detection control unit 93A, together with the stereo cameras 81L and 81R, constitutes the distance detection unit of the present invention. While the inspection head 20 is displaced along the tilt axis TA to the inspection position of the eye E under examination during auto-alignment, the detection control unit 93A controls one of the stereo cameras 81L and 81R to continuously detect the face distance Fd between the inspection head 20 and the face of the subject H. Here, the face distance Fd is, for example, the distance between the inspection head 20 (concave mirror unit 50) and, in particular, the nose N of the subject H, which is likely to be in close proximity to the inspection head 20.

[0105] Specifically, the detection control unit 93A repeatedly (continuously) performs the following actions: controlling the camera to simultaneously capture images of the subject H's face (nose N) from multiple different directions using one of the stereo cameras 81L and 81R while the inspection head 20 is displaced along the tilt axis TA; and acquiring images of the face from one of the stereo cameras 81L and 81R.

[0106] In this case, depending on the shooting conditions (angle of view, direction of the optical axis) of one of the stereo cameras 81L or 81R, it may be impossible to capture the nose N with all the cameras (not shown) that make up one of the stereo cameras 81L or 81R. In such cases, the detection control unit 93A repeatedly performs the following: capturing the face (nose N) with one or more cameras (if the stereo cameras 81L and 81R are composed of three or more cameras) that can capture the nose N on the tilt axis TA, and acquiring the captured images from one or more cameras that have captured the nose N.

[0107] Then, when a face (nose N) is captured by multiple cameras constituting one of the stereo cameras 81L, 81R, the detection control unit 93A repeatedly calculates the face distance Fd based on the face image captured by each camera each time a face image is acquired from each camera. For example, the detection control unit 93A analyzes the image captured by each camera using a known method to identify the nose contour from the background, the cheek contour of the subject H from the background, or the nostrils, thereby identifying the image of the nose N (tip of the nose) in each captured image.

[0108] Next, the detection control unit 93A calculates the face distance Fd (relative position of the nose N to the inspection head 20), which is the shortest distance from the inspection head 20 to the nose N, based on the identification result of the nose N image in the captured image for each camera. Note that the method for calculating the distance to various objects using stereo cameras 81L and 81R is a known technique (see, for example, Patent Document 2), so a detailed explanation is omitted here. As a result, the face distance Fd can be continuously detected while the inspection head 20 is displaced along the tilt axis TA to the inspection position of the eye E under examination (see code XVIA in Figure 16).

[0109] On the other hand, if there is one camera among the stereo cameras 81L and 81R that is capable of photographing the nose N on the tilt axis TA, the detection control unit 93A performs photography of the nose N with this camera (corresponding to the specific camera of the present invention) at the initial position of the inspection head 20 and acquires a photographic image of the nose N. In this case, the detection control unit 93A functions as a pre-photography control unit of the present invention.

[0110] Then, each time the detection control unit 93A acquires a new image of the nose N from one camera that has captured the nose N while the inspection head 20 is displaced along the tilt axis TA, it performs a calculation process to calculate the face distance Fd by comparing the size (magnification) of the contour of the nose N image contained in the image of the nose N at the initial position with the contour of the nose N image contained in the image of the nose N at the initial position. This makes it possible to continuously detect the face distance Fd.

[0111] The retraction control unit 93B operates when the face distance Fd, which is continuously detected by the detection control unit 93A, falls below a predetermined threshold while the examination head 20 is displaced along the tilt axis TA to the examination position of the eye E being examined (see symbol XVIB in Figure 16). The retraction control unit 93B drives the swing rotation drive unit 17 to perform retraction control, which moves the examination head 20 away from the face (nose N) of the subject H.

[0112] Specifically, the retraction control unit 93B drives the swing rotation drive unit 17, as shown by the symbol XVIC in Figure 16, to perform retraction control, which rotates the inspection head 20 in the direction that increases the face distance Fd (see arrow R). The direction of rotation of the inspection head 20 that increases the face distance Fd can be determined based on left / right eye information indicating whether the eye E being examined is the left eye OS or the right eye OD, or the outward direction X1 (see the symbol XIIA in Figure 12), etc.

[0113] Figure 17 is an explanatory diagram illustrating a modified example of the retraction control of the inspection head 20 in the first embodiment. As shown by the reference numerals XVIIA and XVIIB in Figure 17, the retraction control unit 93B may drive the swing rotation drive unit 17, the X-axis drive unit 14, and the Z-axis drive unit 15 to perform retraction control when the face distance Fd continuously detected by the detection control unit 93A falls below a threshold.

[0114] Specifically, as shown by the symbol XVIIC in Figure 17, the retraction control unit 93B simultaneously executes a first retraction control and a second retraction control as retraction control. In the first retraction control, the retraction control unit 93B drives the swing rotation drive unit 17 to rotate the inspection head 20 in a direction that increases the face distance Fd, as described in Figure 16 (see arrow R). In the second retraction control, the retraction control unit 93B drives the X-axis drive unit 14 and the Z-axis drive unit 15 to move the inspection head 20 away from the subject H's face (nose N) (in at least one direction in the X-axis direction and the Z-axis direction) (see arrow XZ3).

[0115] The retraction control unit 93B may also drive the X-axis drive unit 14 and the Z-axis drive unit 15 to retract the inspection head 20 in a direction away from the face of the subject H (in at least one direction in the X-axis direction and the Z-axis direction) without driving the swing rotation drive unit 17. In this case, for example, the inspection head 20 may be retracted along the inclination axis TA.

[0116] Furthermore, when the retraction control unit 93B executes the second retraction control, it may drive the Y-axis drive unit 16 in place of, or together with, the X-axis drive unit 14 and the Z-axis drive unit 15, to move the inspection head 20 in the Y-axis direction so that it moves away from the face (nose N) of the subject H. In addition, when the retraction control unit 93B executes the second retraction control, it may stop the driving of the X-axis drive unit 14, the Z-axis drive unit 15, and the Y-axis drive unit 16.

[0117] Returning to Figure 10, once fundus photography of the eye E by the imaging optical system 60 is complete, the drive control unit 93 drives the Z-axis drive unit 15 to retract the examination head 20 by a predetermined distance to the rear (examiner side) in the Z-axis direction (see symbols XXD and XXG in Figure 20, described later).

[0118] The fixation control unit 94 causes the fixation light projection system 770 to project fixation light onto the eye E by the subject eye E, at least from the start of auto-alignment of the examination head 20 until fundus photography of the eye E by the examination head 20 is completed. This allows the subject H's line of sight to be guided and fixed in the direction of the fixation light while the examination head 20 is moved from the initial position through the tilt axis TA to the examination position during auto-alignment. For example, when the examination head 20 is moved from the initial position to the tilt axis TA, the eye E can be rotated to follow this movement. As a result, the line of sight of the eye E can always be fixed to the examination head 20.

[0119] After the auto-alignment of the examination head 20 is completed, the fundus imaging control unit 95 controls the fundus imaging of the eye E under examination using the fundus camera 9. For example, the fundus imaging control unit 95 drives the focusing drive unit 69 in a known manner to focus the imaging optical system 60 (left eye imaging optical system 60L or right eye imaging optical system 60R) on the fundus of the eye E under examination, and also drives the slit drive unit 77 in a known manner to perform focusing control to focus the illumination light (slit light) on the fundus of the eye E under examination.

[0120] Next, the fundus imaging control unit 95 controls the scanner drive unit 78 and the imaging optical system 60 (left eye imaging optical system 60L or right eye imaging optical system 60R) in a known manner to perform slit scan imaging of the fundus, which includes scanning of the slit light on the fundus by the galvanoscanner 37 and fundus imaging at each scanning position of the slit light by the imaging optical system 60. As a result, the image forming unit 120 forms a fundus image of the eye under examination E based on the imaging signal output from one of the fundus image sensors 671L or 671R during the slit scan imaging, and the data processing unit 130 performs various image processing on this fundus image.

[0121] The storage control unit 96 displays the fundus image of the eye E after image processing by the data processing unit 130 on the control panel 40. Furthermore, if the examiner inputs an image saving operation to the control panel 40, the storage control unit 96 saves the fundus image of the eye E to the storage unit 131.

[0122] <Operation of the fundus camera in the first embodiment> Figure 18 is a flowchart showing the flow of fundus imaging of the eye E being examined using the fundus camera 9 of the first embodiment of the above configuration. With the subject H already resting their chin on the chin rest 33 and their forehead against the forehead support frame 32, the examiner operates the control panel 40 to adjust the height position (Y-axis position) of the chin rest 33 to match the subject H. The examiner also operates the control panel 40 to select the auto-alignment mode as the alignment mode for the examination head 20. Furthermore, the fixation control unit 94 starts projecting fixation light onto the eye E being examined using the fixation light projection system 770. This allows the gaze direction of the eye E being examined to be guided and fixed.

[0123] Furthermore, the examiner operates the control panel 40 to select, for example, the left eye OS (or right eye OD) as the eye to be examined E. In response to this selection, the drive control unit 93 drives the unit rotation drive unit 55 to rotate the concave mirror unit 50 to the first position corresponding to the left eye OS (see Figure 4) (step S1). Note that this step S1 may be performed simultaneously with the auto-alignment of the examination head 20 (step S2).

[0124] When the examiner inputs the start of the examination operation to the control panel 40, the auto-alignment of the examination head 20 for the eye under examination E (in this case, the left eye OS) begins (step S2).

[0125] Figure 19 is a flowchart showing the flow of the auto-alignment process of the examination head 20 according to the operating method of the ophthalmic device of the present invention. Figure 20 is an explanatory diagram for illustrating the displacement of the examination head 20 after the start of auto-alignment. Here, the case of performing the auto-alignment described in "Example 1-1" in Figure 12 above will be used as an example for explanation.

[0126] As shown in Figures 19 and 20, the tilt angle determination unit 91 determines the tilt angle θ as the angle previously selected by the inspector on the control panel 40, and then outputs this tilt angle θ information to the drive control unit 93 (step S2A). Based on this tilt angle θ, the drive control unit 93 determines the tilt axis TA and then starts auto-aligning the inspection head 20 (step S2B).

[0127] First, the drive control unit 93 drives the X-axis drive unit 14 to perform a first drive process that moves the inspection head 20 outward in the direction X1 from its initial position to the tilt axis TA when viewed from above in the Y-axis direction (step S2C). Also, the alignment detection unit 92 starts stereo imaging with the stereo camera 81L and repeatedly performs the acquisition of images from the stereo camera 81L and the analysis of each captured image (step S2D).

[0128] Next, the drive control unit 93 drives the swing rotation drive unit 17 to rotate the inspection head 20 around the rotation axis 21 by an inclination angle θ, performing a second drive process (step S2E) to make the central axis CL of the inspection head 20 parallel to the inclination axis TA. As a result, the inspection head 20 is displaced from the initial position shown by the reference numeral XXA in Figure 20 to the inclination axis TA as shown by the reference numeral XXB, and the central axis CL becomes parallel to the inclination axis TA. Furthermore, by projecting fixation light by the fixation light projection system 770, the line of sight direction of the eye under examination E (left eye OS) can also be made to follow the displacement of the inspection head 20.

[0129] 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) that moves the inspection head 20 to the inspection position along the inclination axis TA when viewed from above in the Y-axis direction, as shown by the numeral XXC in Figure 20. By displacing the inspection head 20 to the inspection position along the inclination axis TA during auto-alignment in this way, unlike when the inspection head 20 is displaced along the reference axis VA, the inspection head 20 is prevented from coming into close proximity to the nose N.

[0130] Furthermore, in conjunction with the start of the third drive process, the detection control unit 93A repeatedly performs the following actions: controlling the stereo camera 81L to capture the subject H's face (nose N), and acquiring the face image from the camera that captured the nose N among the multiple cameras constituting the stereo camera 81L. If there are multiple cameras capable of capturing the nose N, the detection control unit 93A repeatedly performs the calculation of the face distance Fd based on the face image captured by each camera (step S2G, corresponding to the distance detection step of the present invention).

[0131] On the other hand, if the nose N cannot be captured by multiple cameras, the detection control unit 93A calculates the face distance Fd based on the result of comparing the newly captured image of the nose N with the image of the nose N at the initial position each time a new image of the nose N is acquired from one camera capable of capturing the nose N is obtained.

[0132] The retraction control unit 93B remains in standby mode until the face distance Fd falls below a threshold during the third drive process (NO in step S2H).

[0133] While the first to third drive processes are being executed, the alignment detection unit 92 waits for alignment detection until the pupil center position of the left eye OS can be determined from the captured image acquired from the stereo camera 81L (NO in step S2I). Then, during auto-alignment, the stereo camera 81L captures the anterior segment of the left eye OS, and this anterior segment image of the left eye OS is input to the alignment detection unit 92 as an captured image from the stereo camera 81L. As a result, the alignment detection unit 92 can determine the pupil center position of the left eye OS based on the anterior segment image input from the stereo camera 81L (YES in step S2I).

[0134] Next, the alignment detection unit 92 performs alignment detection by converting the pupil center position of the left eye OS into three-dimensional coordinates, thereby detecting the relative position of the left eye OS with respect to the inspection head 20 (step S2J). The alignment detection unit 92 then outputs the detection result of the alignment detection to the drive control unit 93.

[0135] Furthermore, if the alignment detection unit 92 is unable to perform alignment detection while the inspection head 20 is moving for a predetermined period of 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 (the same applies to the second embodiment and subsequent embodiments described later). This prevents the inspection head 20 from approaching the eye E under examination while alignment detection is not possible.

[0136] The retraction control unit 93B maintains a standby state even after alignment detection by the alignment detection unit 92 until the face distance Fd detected by the detection control unit 93A falls below a threshold (NO in step S2K).

[0137] The drive control unit 93 drives the X-axis drive unit 14, Z-axis drive unit 15, and 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. Specifically, the drive control unit 93 calculates the difference between the 3D coordinates of the inspection position (target coordinates) determined based on the alignment detection result and the current 3D coordinates of the inspection head 20 (current coordinates), and continues the third drive process until this difference falls below a threshold (steps S2L, S2M, and S2N). As a result, the inspection head 20 is moved to the inspection position while maintaining the tilt angle θ.

[0138] If the difference between the target coordinates and the current coordinates falls below the threshold while the face distance Fd detected by the detection control unit 93A remains above the threshold, 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 to terminate auto-alignment (YES in step S2M).

[0139] On the other hand, if the face distance Fd detected by the detection control unit 93A during the third drive process falls below a threshold, the retraction control unit 93B is activated (YES in step S2H ​​or step S2K). The retraction control unit 93B performs retraction control by driving the swing rotation drive unit 17 to rotate the inspection head 20 as shown in Figure 16, or by driving the swing rotation drive unit 17, the X-axis drive unit 14, and the Z-axis drive unit 15 to simultaneously execute the first retraction control and the second retraction control as shown in Figure 17 (step S2O). Step S2O corresponds to the retraction control step of the present invention. This prevents the inspection head 20 from coming into close proximity to the nose N due to the movement of the subject H's face, the shape and size of the subject H's nose N, etc.

[0140] If the retraction control unit 93B performs retraction control, the tilt angle determination unit 91 may determine a new tilt angle θ (for example, an angle larger than the previous tilt angle θ), and the third drive process may be re-executed along the tilt axis TA corresponding to this new tilt angle θ, i.e., the process from step S2F onward may be repeatedly executed (the same applies to the second embodiment and subsequent embodiments described later).

[0141] Returning to Figures 18 and 20, once auto-alignment is complete, the fundus imaging control unit 95 drives the focus drive unit 69 and the slit drive unit 77 in a known manner to perform focus control to adjust the focus of the imaging optical system 60 (in this case, the left eye imaging optical system 60L) and the illumination light (slit light) to the fundus of the left eye OS (step S3). Next, the fundus imaging control unit 95 controls the scanner drive unit 78 and the left eye imaging optical system 60L in a known manner to perform slit scan imaging of the fundus of the left eye OS (step S4).

[0142] Then, 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 during slit scan imaging, 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.

[0143] Meanwhile, once fundus imaging of the left eye OS is complete, the drive control unit 93 drives the Z-axis drive unit 15 to retract the inspection head 20 to the rear in the Z-axis direction, as shown by the numeral XXD in Figure 20 (step S5).

[0144] 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 the desired fundus image has been obtained. If the desired fundus image has been obtained, the examiner inputs an image saving operation to the control panel 40. As a result, the storage control unit 96 saves the fundus image of the left eye OS to the storage unit 131 (step S6).

[0145] If fundus photography of the right eye OD is to be performed next, the processes from step S1 to step S6 are repeated (YES in step S7). In this case, under the control of the drive control unit 93, the concave mirror unit 50 is rotated to a second position corresponding to the right eye OD (see Figure 5). The inspection head 20 is also displaced to the tilt axis TA corresponding to the right eye OD (see symbol XXE in Figure 20), and then moved along the tilt axis TA to the inspection position of the right eye OD (see symbol XXF in Figure 20). At this time, if the face distance Fd detected by the detection control unit 93A falls below the threshold, the retraction control unit 93B performs retraction control. When fundus photography of the right eye OD is completed, under the control of the drive control unit 93, the inspection head 20 is retracted to the rearward side in the Z-axis direction (see symbol XXG in Figure 20), and then displaced to the initial position (see symbol XXH in Figure 20).

[0146] As described above, in the fundus camera 9 of the first embodiment, if the face distance Fd falls below a threshold while the examination head 20 is moving along the tilt axis TA to the examination position of the eye E during auto-alignment, at least the swing rotation drive unit 17 can be driven to perform retraction control of the examination head 20. This makes it possible to reliably avoid the examination head 20 coming close to the nose N during auto-alignment, regardless of the movement of the subject H's face or the shape and size of the subject H's nose N.

[0147] [Second Embodiment] Figure 21 is a side view of the main part of the fundus camera 9 of the second embodiment. In the fundus camera 9 of the first embodiment described above, the inspection head 20 is rotated (swinged) by a swing rotation drive unit 17 around a rotation axis 21 provided on the lower side of the inspection head 20 in the Y-axis direction. However, as shown in Figure 21, the position of the rotation axis 21 is different in the fundus camera 9 of the second embodiment compared to the first embodiment.

[0148] The fundus camera 9 of the second embodiment has basically the same configuration as the fundus camera 9 of the first embodiment, except that the position of the rotation axis 21 is different. For this reason, parts that are functionally or structurally identical to those of the fundus camera 9 of the first embodiment are denoted by the same reference numerals and their descriptions are omitted.

[0149] In the second embodiment, the swing rotation drive unit 17 and the rotation axis 21 are located closer to the eye under examination E than the examination head 20, that is, on the Z-axis forward side of the examination head 20. This allows the rotation axis 21 and the eye under examination E (center of rotation) to be aligned when viewed from above in the Y-axis direction 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. In this case, the swing rotation drive unit 17 rotates (swings) the examination head 20 around the center of rotation of the eye under examination E.

[0150] 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-aligning the inspection head 20 by the drive control unit 93 is different from that of the first embodiment.

[0151] In the second embodiment, the drive control unit 93, similar to the first 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, Z-axis drive unit 15, Y-axis drive unit 16 and swing rotation drive unit 17 to perform auto-alignment of the inspection head 20.

[0152] Figure 22 is an explanatory diagram illustrating a second-first example of auto-alignment of the inspection head 20 in the second embodiment. As indicated by reference numeral XXIIA in Figure 22, the inspection head 20 is initially positioned in the same initial position as in the first embodiment.

[0153] Next, as shown by the symbols XXIIA and XXIIB in Figure 22, the drive control unit 93 drives the X-axis drive unit 14 and the Z-axis drive unit 15 to perform a first drive process that moves the inspection head 20 (swing rotation drive unit 17 and rotation axis 21) from its initial position in the XZ axis direction (see arrow XZ2). Specifically, the inspection head 20 is moved in the XZ axis direction until the rotation axis 21 coincides with the rotation center of the eye E being examined when viewed from above in the Y axis direction.

[0154] After the completion of the first drive process, the drive control unit 93 drives the swing rotation drive unit 17 to perform a second drive process that rotates the examination head 20 by an inclination angle θ around the rotation axis 21 (the rotation center of the eye being examined E), as shown by the symbol XXIB in Figure 22 (see arrow R). As a result, as shown by the symbol XXIIC in Figure 22, the examination head 20 moves to the inclination axis TA and the central axis CL becomes parallel to the inclination axis TA.

[0155] Next, after the completion of the second drive process, 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 that moves the inspection head 20 to the inspection position along the inclination axis TA when viewed from above in the Y-axis direction, similar to the first embodiment (see arrow XZ1). In the third drive process of the second embodiment, unlike the first embodiment, the Z-axis movement of the inspection head 20 by the X-axis drive unit 14 and the Z-axis drive unit 15 is mainly performed. As a result, the inspection head 20 is moved toward the eye to be examined E while maintaining a constant inclination angle θ.

[0156] Then, as shown by the symbol XXIID in Figure 22, unless the retraction control shown in Figure 24, which will be described later, is executed during auto-alignment, 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 detected by the alignment detection unit 92, and continues the third drive process until the inspection head 20 reaches the inspection position.

[0157] Figure 23 is an explanatory diagram illustrating a second-second example of auto-alignment of the inspection head 20 in the second embodiment. As shown by reference numerals XXIIIA and XXIIIB in Figure 23, 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 direction (see arrow XZ2) and rotates the inspection head 20 by an inclination angle θ (see arrow R). Note that the first drive process in the second-second example is a process that simultaneously performs the first drive process and the second drive process of the "second-first example" described in Figure 22. As a result, the inspection head 20 is moved to the inclination axis TA, and the central axis CL of the inspection head 20 becomes parallel to the inclination axis TA.

[0158] In the first drive process, the inspection head 20 may be displaced along the tilt axis TA by the shortest distance to a position where the stereo cameras 81L and 81R can capture images of the anterior segment of the eye E (in this case, the left eye OS).

[0159] Then, after the completion of 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 a second drive process similar to the third drive process in the previously described "Example 2-1," thereby moving the inspection head 20 to the inspection position along the inclination axis TA when viewed from above in the Y-axis direction (see arrow XZ1). Then, as shown by the symbol XXIIIC in Figure 23, unless the retraction control shown in Figure 24, which will be described later, is performed during the auto-alignment, 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 detected by the alignment detection unit 92, and continues the second drive process until the inspection head 20 reaches the inspection position.

[0160] Figure 24 is an explanatory diagram illustrating an example of the retraction control of the inspection head 20 in the second embodiment. As shown by the reference numerals XXIVA and XXIVB in Figure 24, the detection control unit 93A in the second embodiment repeatedly performs the calculation of the face distance Fd, similar to the first embodiment, while the inspection head 20 is displaced along the tilt axis TA to the inspection position of the eye E under examination.

[0161] In the second embodiment, the retraction control unit 93B drives the swing rotation drive unit 17 when the face distance Fd detected by the detection control unit 93A falls below a predetermined threshold, and performs retraction control to rotate the inspection head 20 around the rotation axis 21 in the direction in which the face distance Fd increases (see arrow R). As described in Figure 17 above, the retraction control unit 93B may also drive at least one of the X-axis drive unit 14, Z-axis drive unit 15, and Y-axis drive unit 16 simultaneously with the swing rotation drive unit 17 to rotate the inspection head 20 and move it in the direction in which the face distance Fd increases. Alternatively, the retraction control unit 93B may drive at least one of the X-axis drive unit 14, Z-axis drive unit 15, and Y-axis drive unit 16 to move the inspection head 20 in the direction in which the face distance Fd increases without rotating it.

[0162] As described above, in the fundus camera 9 of the second embodiment, by performing retraction control when the face distance Fd falls below a threshold, it is possible to reliably avoid the examination head 20 coming into close proximity to the nose N of the subject H during auto-alignment, similar to the first embodiment.

[0163] [Third Embodiment] Figure 25 is a side view of the main part of the fundus camera 9 of the third embodiment. In the fundus camera 9 of the first embodiment, the examination head 20 is brought close to the eye under examination E along the tilt axis TA, which is tilted in the X-axis direction (outward direction X1) when the reference axis VA is tilted during the auto-alignment of the examination head 20. In contrast, in the fundus camera 9 of the third embodiment, the examination head 20 is brought close to the eye under examination E along the tilt axis TA, which is tilted in a direction different from the X-axis direction when the reference axis VA is tilted during the auto-alignment of the examination head 20.

[0164] As shown in Figure 25, 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 around the axis of rotation shafts 21,140, ​​it is equipped with a tilt rotation drive unit 141, and it performs auto-alignment of the examination head 20, which is different from that of the first embodiment. For this reason, components that are functionally or structurally identical to those of the fundus camera 9 of the first embodiment are denoted by the same reference numerals and their descriptions are omitted.

[0165] The rotating shaft 140 is provided between the bottom surface of the inspection head 20 and the tip of the rotating shaft 21. The rotating shaft 140 is perpendicular to the Y-axis direction and holds the inspection head 20 so that it can rotate freely around the axis perpendicular to the Y-axis direction. This allows the inspection head 20 to rotate (tilt: see arrow TL) around the rotating shaft 140 and to rotate (swing: see arrow SW) around the rotating shaft 21. The configuration of the rotating shafts 21 and 140 is not particularly limited as long as the inspection head 20 can swing and tilt.

[0166] The tilt rotation drive unit 141 corresponds to the rotation mechanism of the present invention. Furthermore, the tilt rotation drive unit 141, together with the X-axis drive unit 14, Z-axis drive unit 15, Y-axis drive unit 16 and swing rotation drive unit 17 described above, constitute the displacement mechanism of the present invention. The tilt rotation drive unit 141 has, for example, a motor, a worm gear, and a motor drive circuit, and rotates (tilts) the inspection head 20 around the rotation axis 140.

[0167] Thus, in the third embodiment, the inspection head 20 can be rotated (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, upward in the Y-axis direction, is defined as "outward direction Y1 (see Figure 26)," and the axis tilted with the reference axis VA tilted in the "outward direction Y1" with the eye E under examination as the center is defined as the tilt axis TA.

[0168] 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.

[0169] The inclination angle determination unit 91 of the third embodiment determines the inclination angle θ of the inclination axis TA in the outward direction Y1 (see Figure 26) with respect to the reference axis VA when viewed from one direction in the X-axis direction, that is, the inclination angle θ of the inclination axis TA with respect to the reference axis VA in the YZ plane. The specific method for determining the inclination angle θ is the same as the method for determining the inclination angle θ of the first embodiment described above, except that the inclination direction of the inclination axis TA is different, so a detailed explanation is omitted here.

[0170] In the third embodiment, the drive control unit 93 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, Z-axis drive unit 15, Y-axis drive unit 16, swing rotation drive unit 17, and tilt rotation drive unit 141 to perform auto-alignment of the inspection head 20.

[0171] Figure 26 is an explanatory diagram illustrating a third example of auto-alignment of the inspection head 20 in the third embodiment. This third example is basically the same as the 1-1 example (see Figure 12) described in the first embodiment, except that the inclination direction of the tilt axis TA is different.

[0172] As shown by reference numeral XXVIA in Figure 26, the inspection head 20 is initially positioned 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 perform a first drive process that moves the inspection head 20 outward Y1 (upward in the Y-axis direction) from the initial position to the inclination axis TA when viewed from one side in the X-axis direction.

[0173] As shown by the symbol XXVIB in Figure 26, the drive control unit 93 drives the tilt rotation drive unit 141 after the completion of the first drive process to perform a second drive process that rotates the inspection head 20 by an inclination angle θ around the rotation axis 140 (see arrow R). As a result, as shown by the symbol XXVIC in Figure 26, the central axis CL of the inspection head 20 becomes parallel to the inclination axis TA. Note that the second drive process may be performed before the first drive process.

[0174] Next, after the completion of the second 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 start a third drive process that moves the inspection head 20 to the inspection position along the tilt axis TA when viewed from one direction in the X-axis direction (see arrow YZ1). As a result, the inspection head 20 is moved toward the eye E under examination while maintaining a constant tilt angle θ. If the face distance Fd detected by the detection control unit 93A falls below a threshold during this third drive process, the retraction control unit 93B performs retraction control as in each of the embodiments described above.

[0175] Then, as shown by the symbol XXVID in Figure 26, unless retraction control is performed during auto-alignment, 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 detected by the alignment detection unit 92, and continues the third drive process until the inspection head 20 reaches the inspection position.

[0176] In addition, similar to the first and second examples of auto-alignment of the inspection head 20 in the first embodiment (see Figure 13), the inspection head 20 may first be moved a predetermined distance forward in the Z-axis direction (towards the eye E being examined) before starting the first drive process described above. Furthermore, similar to the first and third examples of auto-alignment of the inspection head 20 in the first embodiment (see Figure 14), the first drive process may be performed 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 an inclination angle θ.

[0177] As described above, in the fundus camera 9 of the third embodiment, when the examination head 20 is moved along the tilt axis TA from diagonally above to the examination position of the eye E under examination, retraction control is performed if the face distance Fd falls below a threshold, thus achieving the same effects as in each of the above embodiments.

[0178] In the third embodiment described above, during auto-alignment of the examination head 20, the examination head 20 is brought closer to the eye E by following the tilt axis TA, which is tilted outward Y1 (upward in the Y-axis direction) with the reference axis VA centered on the eye E. However, 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 and 140 can be appropriately changed according to this tilt direction.

[0179] Furthermore, in the fundus camera 9 of the third embodiment described above, if the tilt direction of the tilt axis TA is fixed to the outward direction Y1, the swing rotation drive unit 17 may be omitted.

[0180] [Fourth Embodiment] Next, the fundus camera 9 of the fourth embodiment of the present invention will be described. In the fundus camera 9 of the second embodiment described above (see Figure 21), the examination head 20 is brought close to the eye under examination E along the tilt axis TA, which is tilted in the X-axis direction (outward X1) when the reference axis VA is tilted during auto-alignment of the examination head 20. In contrast, the fundus camera 9 of the fourth embodiment brings the examination head 20 close to the eye under examination E along the tilt axis TA, which is tilted in the outward Y1 direction (upward in the Y-axis direction), similar to the fundus camera 9 of the third embodiment described above (see Figures 25 and 26).

[0181] The fundus camera 9 of the fourth embodiment, although not shown in the figures, has basically the same configuration as the fundus camera 9 of the second embodiment, except that the examination head 20 can be rotated (swing and tilted) on two axes, a rotation axis 21 and a rotation axis 140, similar to the fundus camera 9 of the third embodiment (see Figure 25). For this reason, components that are functionally or structurally identical to those of the fundus camera 9 of each of the above embodiments are given the same reference numerals and their descriptions are omitted. The specific configuration of the tilt mechanism (rotation axis 140 and tilt rotation drive unit 141) used in the fundus camera 9 of the fourth embodiment is known technology (see, for example, Japanese Patent Application Publication No. 2022-112637), so a specific description is omitted here.

[0182] 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. Furthermore, 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, similar to the tilt angle determination unit 91 of the third embodiment. In addition, 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.

[0183] Figure 27 is an explanatory diagram illustrating a fourth example of auto-alignment of the inspection head 20 in the fourth embodiment. This fourth example is basically the same as the 2-1 example (see Figure 21) described in the second embodiment, except that the inclination direction of the tilt axis TA is different. As indicated by the reference numeral XXVIIA in Figure 27, the inspection head 20 is initially positioned in the same initial position as in the first embodiment.

[0184] Next, as shown by the symbols XXVIIA and XXVIIB in Figure 27, 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 that moves the examination head 20 in the XYZ directions until the rotation axis 21 and the rotation axis 140 coincide with the rotation center of the eye under examination E.

[0185] After the completion of the first drive process, the drive control unit 93 drives the tilt rotation drive unit 141 to perform a second drive process that rotates the inspection head 20 outward by an angle θ around the rotation axis 140 (the rotation center of the eye being examined E) in the direction Y1 (see arrow R). As a result, as shown by the symbol XXVIIC in Figure 27, the inspection head 20 moves to the tilt axis TA and the central axis CL becomes parallel to the tilt axis TA.

[0186] Next, after the completion of the second 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 start a third drive process that moves the inspection head 20 to the inspection position along the tilt axis TA when viewed from one direction in the X-axis direction (see arrow YZ1). As a result, the inspection head 20 is moved toward the eye E under examination while maintaining a constant tilt angle θ. If the face distance Fd detected by the detection control unit 93A falls below a threshold during this third drive process, the retraction control unit 93B performs retraction control as in each of the embodiments described above.

[0187] Then, as shown by the symbol XXVIID in Figure 27, unless retraction control is performed during auto-alignment, 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 detected by the alignment detection unit 92, and continues the third drive process until the inspection head 20 reaches the inspection position.

[0188] Furthermore, the first drive process and the second drive process may be executed simultaneously, similar to the second example of auto-alignment of the inspection head 20 in the second embodiment described above (see Figure 23).

[0189] As described above, in the fundus camera 9 of the fourth embodiment, when the examination head 20 is moved along the tilt axis TA from diagonally above to the examination position of the eye E under examination, retraction control is performed if the face distance Fd falls below a predetermined threshold, thus achieving the same effects as in each of the above embodiments.

[0190] In the fourth embodiment described above, during auto-alignment of the examination head 20, the examination head 20 is brought closer to the eye E by following the tilt axis TA, which is tilted outward Y1 (upward in the Y-axis direction) with the reference axis VA centered on the eye E. However, the tilt direction of the 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 and 140 can be appropriately changed according to this tilt direction.

[0191] Furthermore, in the fundus camera 9 of the fourth embodiment described above, if the tilt direction of the tilt axis TA is fixed to the outward direction Y1, the swing rotation drive unit 17 may be omitted.

[0192] [Fifth Embodiment] Figure 28 is a front view of the inspection head 20 of the fundus camera 9 of the fifth embodiment. In each of the above embodiments, the detection control unit 93A of the fundus camera 9 detects the face distance Fd using stereo cameras 81L and 81R, but the face distance Fd may be detected using other methods.

[0193] As shown in Figure 28, the fundus camera 9 of the fifth embodiment has basically the same configuration as the fundus camera 9 of each of the above embodiments, except that it is equipped with a plurality of non-contact distance measuring sensors 150. For this reason, components that are functionally or structurally identical to the fundus camera 9 of each of the above embodiments are denoted by the same reference numerals and their descriptions are omitted.

[0194] Each distance measuring sensor 150, together with the detection control unit 93A, constitutes the distance detection unit of the present invention and is provided, for example, on the front surface of the inspection head 20. The position of each distance measuring sensor 150 on the inspection head 20 is not particularly limited as long as it is a position in which the face of the subject H supported by the face support unit 30 can be detected. Furthermore, there may be as few as one distance measuring sensor 150. As each distance measuring sensor 150, various known distance measuring sensors such as photoelectric sensors, optical fiber sensors, laser sensors, camera-integrated laser displacement sensors, ultrasonic sensors, or capacitive sensors can be used. Alternatively, a stereo camera (multi-lens camera) for measuring face distance Fd may be used as the distance measuring sensor 150.

[0195] In the fifth embodiment, the detection control unit 93A repeatedly performs the acquisition of detection signals output from each distance measuring sensor 150 and the calculation of the face distance Fd based on the detection signals from each distance measuring sensor 150 while the inspection head 20 is displaced along the tilt axis TA to the inspection position of the eye E being examined. As a result, the retraction control unit 93B of the fifth embodiment can drive at least the swing rotation drive unit 17 to perform retraction control of the inspection head 20 in the same manner as in the above embodiments when the face distance Fd detected by the detection control unit 93A falls below a threshold. As a result, the same effects as in the above embodiments can be obtained. Furthermore, the fifth embodiment is also effective when the face distance Fd falls below a threshold due to a shift in the position of the subject H's face during auto-alignment.

[0196] [others] In each of the above embodiments, alignment detection and measurement of face distance Fd are performed using stereo cameras 81L and 81R. However, alignment detection and measurement of face distance Fd may also be performed using various imaging units provided on the inspection head 20 other than the stereo cameras 81L and 81R. In this case, the stereo cameras 81L and 81R can be omitted.

[0197] In each of the above embodiments, the inspection head 20 is moved to the inspection position of the eye E under examination from an oblique direction along the tilt axis TA during auto-alignment. However, the inspection head 20 may also be moved to the inspection position of the eye E under examination from an oblique direction along the tilt axis TA during manual alignment. In this case as well, if the face distance Fd detected by the detection control unit 93A falls below a threshold, the retraction control unit 93B performs retraction control in the same manner as in each of the above embodiments.

[0198] In each of the above embodiments, the distance between the inspection head 20 and the nose N is detected as the face distance Fd under the control of the detection control unit 93A. However, the distance between the inspection head 20 and parts of the subject H's face other than the nose N may also be detected.

[0199] In the embodiments described above, the displacement mechanism for displacing the examination head 20 relative to the eye E under examination was described using an X-axis drive unit 14, a Z-axis drive unit 15, a Y-axis drive unit 16, and a swing rotation drive unit 17, and also using a tilt rotation drive unit 141 as an example. However, the configuration and type of this displacement mechanism are not particularly limited. For example, a robot arm (articulated arm) may be used as the displacement mechanism of the present invention.

[0200] In the retraction control of the inspection head 20 in each of the above embodiments, the inspection head 20 is rotated (swing, tilt) in the direction of the rotation axis 21,140. However, the inspection head 20 may be retracted from the face of the subject H without rotating the inspection head 20. In this case, the inspection head 20 may be retracted in at least one direction in the XYZ axis direction (for example, outward X1, outward Y1, upward in the Y direction, backward in the Z direction), or retracted along the tilt axis TA.

[0201] In the embodiments described above, a fundus camera 9 was used as an example of the ophthalmic device of the present invention. However, the present invention is not limited thereto, and can be applied to various ophthalmic devices that perform examinations (measurement of ocular characteristics, photography, observation, etc.) of various parts of the eye E to be examined via a pair of concave mirrors.

[0202] <Note> As can be seen from the descriptions of the embodiments detailed above, this specification includes disclosures of a variety of technical ideas, including the inventions shown below.

[0203] (Additional note 1) An examination head comprising: an illumination optical system that emits illumination light to illuminate the eye under examination; and an imaging optical system that guides the reflected light from the eye irradiated with the illumination light to an image sensor; A pair of concave mirrors are provided on the inspection head, which form an optical path between the inspection head and the eye under examination for the illumination light and the reflected light, A displacement mechanism for displacing the examination head relative to the eye being examined, A drive control unit drives the displacement mechanism to displace the inspection head along the inclined axis to the inspection position of the eye under examination, when the reference axis is parallel to the front-to-back direction which is the operating distance direction of the inspection head and passes through the eye under examination, and the inclined axis is an axis tilted outward from the reference axis with the eye under examination as the center and away from the nose of the person under examination, While the inspection head is displaced along the tilt axis by the displacement mechanism, a distance detection unit detects the face distance, which is the distance between the inspection head and the face of the person being examined. When the face distance detected by the distance detection unit falls below a predetermined threshold, the retraction control unit drives the displacement mechanism to retract the inspection head away from the face, An ophthalmic device equipped with the following features.

[0204] (Additional note 2) An examination head comprising: an illumination optical system that emits illumination light to illuminate the eye under examination; and an imaging optical system that guides the reflected light from the eye irradiated with the illumination light to an image sensor; A pair of concave mirrors are provided on the inspection head, which form an optical path between the inspection head and the eye under examination for the illumination light and the reflected light, A displacement mechanism for displacing the examination head relative to the eye being examined, In a method for operating an ophthalmic device equipped with the following features, A drive control step in which the displacement mechanism is driven to displace the inspection head along the inclined axis to the inspection position of the eye under examination, with the reference axis being an axis parallel to the front-to-back direction which is the operating distance direction of the inspection head and passing through the eye under examination, and the tilt axis being an axis tilted outward from the reference axis with the eye under examination as the center and away from the nose of the person under examination, While the inspection head is displaced along the tilt axis by the displacement mechanism, a distance detection step is performed to detect the face distance, which is the distance between the inspection head and the face of the subject. If the face distance detected in the distance detection step falls below a predetermined threshold, the displacement mechanism is driven to retract the inspection head away from the face in a retraction control step; A method for operating an ophthalmic device having a specific feature. [Explanation of symbols]

[0205] 9… Fundus camera 10… Equipment 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... Picture frame support 32a... Forehead support surface for the left eye 32b...Forehead surface for right eye 33... Chin rest 33a... Chin rest surface for the left eye 33b…Right eye chin rest surface 34…Lifting rod 35...Jaw support drive unit 37... Galvanometer Scanner 40... Control Panel 41…Touchscreen 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 Unit 57L, 57R... Dichroic mirrors 60…Photography Optical System 60L…Left eye imaging optical system 60R…Photography optical system for right eye 61, 61R...First Reflecting Mirror 62L, 62R…First lens unit 63L, 63R... Second reflective 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 Diameter 72... Slit Unit 72a... Slit 72b…Projection lens 73... Galvanometer Scanner 75…Left / Right Switching Mirror 75a... Mirror rotation axis 77... Slit drive unit 78... Scanner drive unit 79...Mirror rotation drive unit 80… Alignment Optics 80L… Alignment optics for the left eye 80R… Right eye alignment optics 81L, 81R… Stereo Camera 82L, 82R… Alignment lighting lamps 90...Control device 91... Inclination angle determination unit 92... Alignment detection unit 93... Drive control unit 93A...Detection and Control Unit 93B... Evacuation Control Unit 94…Fixation control unit 95... Fundus imaging 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 150... Distance measuring sensor 600L, 600R... Shooting aperture 671L, 671R... Fundus image sensor 741...First Reflecting Mirror 742...Second Reflecting Mirror 744L, 744R… Fourth reflective 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...Eye being examined F1…1st focal point F2, F3, F4…Focus Fd...Facial distance H... Subject N…Nose OD…Right eye OS…Left eye T... Optical Table TA... Inclined axis VA…Reference axis θ...angle of inclination

Claims

1. An examination head comprising: an illumination optical system that emits illumination light to illuminate the eye under examination; and an imaging optical system that guides the reflected light from the eye irradiated with the illumination light to an image sensor; A pair of concave mirrors are provided on the inspection head, which form an optical path between the inspection head and the eye under examination for the illumination light and the reflected light, A displacement mechanism for displacing the examination head relative to the eye being examined, A drive control unit drives the displacement mechanism to displace the inspection head along the inclined axis to the inspection position of the eye under examination, when the reference axis is parallel to the front-to-back direction which is the operating distance direction of the inspection head and passes through the eye under examination, and the inclined axis is an axis tilted outward from the reference axis with the eye under examination as the center and away from the nose of the person under examination, While the inspection head is displaced along the tilt axis by the displacement mechanism, a distance detection unit detects the face distance, which is the distance between the inspection head and the face of the person being examined. When the face distance detected by the distance detection unit falls below a predetermined threshold, the retraction control unit drives the displacement mechanism to rotate the inspection head around a predetermined rotation axis in a direction that increases the face distance, An ophthalmic device equipped with the following features.

2. The ophthalmic apparatus according to claim 1, wherein the distance detection unit detects the distance between the examination head and the nose of the subject as the face distance.

3. The aforementioned displacement mechanism, A movement mechanism for moving the examination head in the forward / backward, left / right, and up / down directions relative to the eye being examined, A rotation mechanism that rotates the inspection head around the aforementioned rotation axis, Includes, The ophthalmic apparatus according to claim 1, wherein the retraction control unit performs a first retraction control, which drives the rotation mechanism to rotate the inspection head in a direction that increases the distance to the face, and a second retraction control, which stops the drive of the movement mechanism or drives the movement mechanism to retract the inspection head in a direction that moves it away from the face.

4. The aforementioned displacement mechanism, A movement mechanism for moving the examination head in the forward / backward, left / right, and up / down directions relative to the eye being examined, A rotation mechanism that rotates the inspection head around the aforementioned rotation axis, Includes, The aforementioned rotating shaft is provided on the lower side of the inspection head, The ophthalmic apparatus according to any one of claims 1 to 3, wherein the moving mechanism moves the inspection head and the rotation axis together in the front-to-back direction, the left-to-right direction and the up-and-down direction.

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

6. The rotation axis is perpendicular to the vertical direction, The ophthalmic apparatus according to claim 4, wherein the outward direction is upward in the vertical direction.

7. The aforementioned displacement mechanism, A movement mechanism for moving the examination head in the forward / backward, left / right, and up / down directions relative to the eye being examined, A rotation mechanism that rotates the inspection head around the aforementioned rotation axis, Includes, The rotation axis is located on the front side in the front-to-back direction, closer to the eye being examined than the examination head. The ophthalmic apparatus according to any one of claims 1 to 3, wherein the moving mechanism moves the inspection head and the rotation axis together in the front-to-back direction, the left-to-right direction and the up-and-down direction.

8. The rotation axis is parallel to the vertical direction, The ophthalmic apparatus according to claim 7, wherein the outward direction is parallel to the left-right direction.

9. The rotation axis is perpendicular to the vertical direction, The ophthalmic apparatus according to claim 7, wherein the outward direction is upward in the vertical direction.

10. The distance detection unit, Multiple cameras are provided on the inspection head, While the inspection head is displaced along the tilt axis by the displacement mechanism, the detection control unit repeatedly performs the following: shooting control to cause the multiple cameras to photograph the face from multiple different directions, and calculation of the face distance based on the captured images of the face taken by each of the multiple cameras. An ophthalmic apparatus according to any one of claims 1 to 3, comprising:

11. The distance detection unit, Multiple cameras are provided on the inspection head, A pre-shooting control unit causes the nose to be photographed by one specific camera capable of photographing the nose among a plurality of cameras at the initial position of the inspection head, A detection control unit repeatedly performs the following: taking a picture of the nose with the specific camera while the inspection head is displaced along the tilt axis by the displacement mechanism; and calculating the face distance by comparing the newly taken image of the nose with the image of the nose taken at the initial position with the image of the nose taken at the initial position. The ophthalmic apparatus according to claim 2, comprising:

12. The distance detection unit, A non-contact distance measuring sensor is provided on the inspection head, While the inspection head is displaced along the tilt axis by the displacement mechanism, a detection control unit repeatedly performs the calculation of the face distance based on the detection signal output from the distance measuring sensor, An ophthalmic apparatus according to any one of claims 1 to 3, comprising:

13. 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 reflective surface facing the eye being examined, The second concave mirror has a second reflective surface that partially faces the first reflective surface and reflects the illumination light from the illumination optical system to the first reflective surface and the reflected light from the first reflective surface to the imaging optical system. The ophthalmic apparatus according to any one of claims 1 to 3, comprising a switching mechanism that allows the pair of concave mirrors to be switched between a first position in which the first reflective surface is positioned in front of the left eye and the second reflective surface is positioned on the left side of the face when the eye being examined is the left eye, and a second position in which the first reflective surface is positioned in front of the right eye and the second reflective surface is positioned on the right side of the face when the eye being examined is the right eye.

14. An examination head comprising: an illumination optical system that emits illumination light to illuminate the eye under examination; and an imaging optical system that guides the reflected light from the eye irradiated with the illumination light to an image sensor; A pair of concave mirrors are provided on the inspection head, which form an optical path between the inspection head and the eye under examination for the illumination light and the reflected light, A displacement mechanism for displacing the examination head relative to the eye being examined, In a method for operating an ophthalmic device equipped with the following features, A drive control step in which the displacement mechanism is driven to displace the inspection head along the inclined axis to the inspection position of the eye under examination, with the reference axis being an axis parallel to the front-to-back direction which is the operating distance direction of the inspection head and passing through the eye under examination, and the tilt axis being an axis tilted outward from the reference axis with the eye under examination as the center and away from the nose of the person under examination, While the inspection head is displaced along the tilt axis by the displacement mechanism, a distance detection step is performed to detect the face distance, which is the distance between the inspection head and the face of the subject. If the face distance detected in the distance detection step falls below a predetermined threshold, the displacement mechanism is driven to rotate the inspection head around a predetermined rotation axis in a direction that increases the face distance (retraction control step), A method for operating an ophthalmic device having a specific feature.

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