Fundus camera and control method thereof

Abstract

To provide a fundus camera capable of reliably executing ophthalmography while the pupil of a subject eye is not miotic, and a control method of the fundus camera.SOLUTION: The fundus camera comprises: a camera body which images the fundus of a subject eye; an anterior eye image acquisition unit which repetitively acquires an anterior eye image of the subject eye at least before the camera body images the fundus; a pupil diameter detection unit which repetitively detects the pupil diameter of the subject eye based on the anterior eye image acquired repetitively by the anterior eye image acquisition unit; and an imaging control unit which when the pupil diameter detected by the pupil diameter detection unit is a predetermined first threshold value or more, controls the camera body to execute imaging of the fundus.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a fundus camera for photographing the fundus of a subject's eye and a control method thereof. [Background technology]

[0002] Fundus cameras that photograph the fundus of a subject's eye are well known (see Patent Documents 1 to 3). These fundus cameras illuminate the fundus of the subject's eye with observation illumination light (such as flash light) and photograph the fundus illuminated by the observation illumination light. Known methods for photographing the fundus with this fundus camera include continuous photography, in which multiple photographs of the same subject's eye are taken in succession, and left-right eye photography, in which the funduses of the left and right subjects' eyes are photographed in turn. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-171221 A [Patent Document 2] Japanese Patent Application Publication No. 5-199997 [Patent Document 3] JP 2013-248376 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, the observation illumination light (e.g., flash light) irradiated from the fundus camera to the fundus when photographing the fundus of the subject's eye contains light in the visible wavelength range and has a large amount of light. For this reason, in photographing the fundus of a non-mydriatic subject's eye, the pupil of the subject's eye constricts when the observation illumination light is irradiated from the fundus camera to the subject's eye when photographing the fundus, and it takes time for this constriction to subside (for the pupil diameter to return to its original size). For this reason, when the above-mentioned continuous photographing is performed with the fundus cameras described in the above patent documents, there is a risk that the pupil constriction will not subside when photographing the fundus of the subject's eye for the second or subsequent times, and good fundus images cannot be obtained.

[0005] In addition, since the pupil diameters of the left and right eyes change by the same amount, when photographing the left and right eyes with the fundus camera described in each of the above patent documents, that is, when photographing the fundus of one of the left and right eyes and then photographing the other of the left and right eyes, the pupil of the other eye may not have contracted. Furthermore, if illumination light is irradiated onto the subject's eye by another ophthalmic device before the fundus photographing of the subject's eye by the fundus camera, the pupil may not have contracted even in the first fundus photographing of the subject's eye by the fundus camera. As a result, a good fundus image may not be obtained.

[0006] The present invention has been made in consideration of the above circumstances, and has an object to provide a fundus camera and a control method thereof that can reliably photograph the fundus when the pupil of the test eye is not constricted. [Means for solving the problem]

[0007] A fundus camera for achieving the object of the present invention comprises a camera body for photographing the fundus of a test eye, an anterior segment image acquisition unit for repeatedly acquiring anterior segment images of the test eye at least before photographing the fundus by the camera body, a pupil diameter detection unit for repeatedly detecting the pupil diameter of the test eye based on the anterior segment images repeatedly acquired by the anterior segment image acquisition unit, and an imaging control unit for causing the camera body to photograph the fundus when the pupil diameter detected by the pupil diameter detection unit is equal to or greater than a predetermined first threshold value.

[0008] According to this fundus camera, fundus photography can be postponed until the pupil diameter of the subject's eye becomes equal to or larger than a first threshold value, and fundus photography can be performed when the pupil diameter becomes equal to or larger than the first threshold value.

[0009] In a fundus camera according to another aspect of the present invention, the camera body has an illumination optical system for illuminating the fundus with imaging illumination light in the visible wavelength range when imaging the fundus, and performs a first imaging of the fundus and a second imaging after the first imaging, and the imaging control unit waits for the camera body to perform the second imaging until the pupil diameter becomes equal to or greater than a first threshold based on a detection result of the pupil diameter repeatedly detected by the pupil diameter detection unit after the first imaging and before the start of the second imaging, and causes the camera body to perform the second imaging when the pupil diameter becomes equal to or greater than the first threshold. Thus, even if the pupil of the subject's eye contracts during the first imaging, the second imaging can be automatically performed when the contraction subsides.

[0010] In another aspect of the present invention, a fundus camera includes a threshold determination unit that determines a first threshold based on the pupil diameter detected by the pupil diameter detection unit before the first photographing, and an photographing control unit causes the camera body to perform the second photographing when the pupil diameter detected by the pupil diameter detection unit is equal to or greater than the first threshold determined by the threshold determination unit. This makes it possible to determine the first threshold corresponding to each subject individually even if there are individual differences in pupil diameter for each subject.

[0011] In a fundus camera according to another aspect of the present invention, the camera body performs a first photographing operation and a second photographing operation on the same subject's eye.

[0012] In a fundus camera according to another aspect of the present invention, when the subject eyes are left and right eyes, the camera body takes a first image of one of the left and right eyes and takes a second image of the other of the left and right eyes.

[0013] A fundus camera according to another aspect of the present invention includes a small pupil diameter aperture that is disposed in an optical path of an illumination optical system and corresponds to an eye with a small pupil diameter, and a first special photography control unit that, based on a pupil diameter repeatedly detected by a pupil diameter detection unit after a first photographing and before the start of a second photographing, causes the camera body to photograph the fundus with the small pupil diameter aperture disposed in the optical path when the pupil diameter is less than a first threshold value even after a predetermined fixed time has elapsed. This makes it possible to photograph a fundus image in a short time.

[0014] In another aspect of the present invention, a fundus camera includes a time prediction unit that predicts a return time until the pupil diameter expands to a first threshold based on a detection result of the pupil diameter detection unit when the camera body executes the first photographing, and a notification unit that notifies the return time predicted by the time prediction unit, thereby allowing the examiner to recognize the return time, i.e., the timing when the second photographing is started.

[0015] In a fundus camera according to another aspect of the present invention, the time prediction section predicts the return time based on the detection result of the pupil diameter detection section and the type of imaging illumination light.

[0016] In a fundus camera according to another aspect of the present invention, a time prediction unit detects a change in pupil diameter after the first photograph is taken based on the pupil diameter repeatedly detected by the pupil diameter detection unit, and calculates a return time based on the detection result of the change in pupil diameter.

[0017] In a fundus camera according to another aspect of the present invention, the camera body has an illumination optical system that illuminates the fundus with imaging illumination light in the visible wavelength range, and is equipped with a small pupil diameter determination unit that determines whether the eye to be examined is a small pupil diameter eye based on the detection result of the pupil diameter detection unit, a small pupil diameter aperture that is arranged so as to be positionable in the optical path of the illumination optical system and corresponds to the small pupil diameter eye, and a second special imaging control unit that causes the camera body to photograph the fundus with the small pupil diameter aperture positioned in the optical path when the small pupil diameter determination unit determines that the eye to be examined is a small pupil diameter eye. Thus, when the eye to be examined is a small pupil diameter eye, the small pupil diameter aperture can be automatically positioned in the optical path of the illumination light.

[0018] In a fundus camera according to another aspect of the present invention, a small pupil diameter determination unit determines whether or not the subject's eye is a small pupil diameter eye based on whether or not the pupil diameter detected by the pupil diameter detection unit is less than a second threshold value that is a predetermined second threshold value and is smaller than the first threshold value. 。

[0019] A control method for a fundus camera for achieving the object of the present invention is a control method for a fundus camera that photographs the fundus of a test eye, which includes an anterior segment image acquisition step of repeatedly acquiring anterior segment images of the test eye at least before photographing the fundus, a pupil diameter detection step of repeatedly detecting the pupil diameter of the test eye based on the anterior segment images repeatedly acquired in the anterior segment image acquisition step, and an imaging control step of performing fundus imaging when the pupil diameter detected in the pupil diameter detection step is equal to or greater than a predetermined first threshold value. Effect of the Invention

[0020] The present invention can reliably perform fundus photography when the pupil of the subject's eye is not constricted. [Brief description of the drawings]

[0021] [Figure 1] 1 is a front perspective view of an ophthalmic apparatus according to a first embodiment as viewed from a subject's side. [Diagram 2] FIG. 2 is a rear perspective view of the ophthalmologic apparatus as seen from the examiner's side. [Diagram 3] 2 is a schematic diagram showing an example of the configuration of a measurement head of an ophthalmologic apparatus. FIG. [Figure 4] 2 is a functional block diagram of an arithmetic control unit of the ophthalmologic apparatus of the first embodiment. FIG. [Diagram 5] 5 is an explanatory diagram for explaining detection of a pupil diameter by a pupil diameter detection unit; FIG. [Figure 6] 11 is an explanatory diagram for explaining the photographing control of the fundus camera unit in a continuous photographing mode by the photographing control unit. FIG. [Figure 7] 11 is an explanatory diagram for explaining the photographing control of the fundus camera unit in the left and right eye photographing mode by the photographing control unit. FIG. [Figure 8] 5 is a flowchart showing a flow of processing for photographing a fundus of an examinee's eye by the ophthalmologic apparatus of the first embodiment. [Figure 9] 10 is a flowchart showing a flow of processing for photographing the fundus of an examinee's eye by an ophthalmologic apparatus according to a second embodiment. [Figure 10] FIG. 11 is a functional block diagram of an arithmetic control unit of an ophthalmic apparatus according to a third embodiment. [Figure 11] 13 is a flowchart showing a flow of processing for photographing the fundus of an examinee's eye by an ophthalmologic apparatus according to a third embodiment. [Figure 12] FIG. 13 is a functional block diagram of an arithmetic control unit of an ophthalmic apparatus according to a fourth embodiment. [Figure 13] FIG. 4 is an explanatory diagram for explaining a first example of prediction of a return time by a time prediction unit. [Figure 14] FIG. 11 is an explanatory diagram for explaining a second example of prediction of a return time by the time prediction unit. [Figure 15] FIG. 11 is an explanatory diagram for explaining an example of display of return time information on a monitor. [Figure 16] 13 is a flowchart showing a flow of processing for photographing the fundus of an examinee's eye by an ophthalmologic apparatus according to a fourth embodiment. [Figure 17] 13 is a flowchart showing a flow of processing for photographing the fundus of an examinee's eye by an ophthalmologic apparatus according to a fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] [Overall configuration of the ophthalmic apparatus according to the first embodiment] Fig. 1 is a front perspective view of an ophthalmic device 10 of a first embodiment as viewed from the subject side. Fig. 2 is a rear perspective view of the ophthalmic device 10 as viewed from the examiner side. In the drawings, the X direction is the left-right direction based on the subject (the interpupillary direction of the subject's eye E shown in Fig. 3), the Y direction is the up-down direction, and the Z direction is the front-rear direction (also called the working distance direction) parallel to the front direction approaching the subject and the rear direction away from the subject.

[0023] As shown in Figures 1 and 2, the ophthalmologic apparatus 10 is a combination machine that combines a fundus camera (non-mydriatic fundus camera) and an optical coherence tomography (OCT) that obtains an OCT image, which is a tomographic image, using OCT.

[0024] The ophthalmic apparatus 10 performs fundus photography to photograph the fundus Ef (see FIG. 3) of a non-mydriatic subject's eye E (see FIG. 3), and also performs OCT measurement to obtain an OCT image of the fundus Ef of the subject's eye E. The ophthalmic apparatus 10 also has a continuous photography mode and a left and right eye photography mode as photography modes for photographing the fundus of the subject's eye E, in addition to a normal photography mode in which fundus photography is performed only once. The continuous photography mode is a mode in which fundus photography is performed multiple times consecutively for the same subject's eye E. The left and right eye photography mode is a mode in which fundus photography is performed sequentially for the left and right subject's eyes E (left and right eyes).

[0025] The ophthalmic apparatus 10 includes a base 11, a face support 12, a stand 13, and a measurement head 14.

[0026] The base 11 is provided with a face support part 12 and a stand 13 .

[0027] The face support part 12 is provided integrally with the base 11 at a position on the front side in the Z direction of the measurement head 14. This face support part 12 has a chin rest 12a and a forehead rest 12b whose positions can be adjusted in the Y direction (up and down direction), and supports the subject's face in a position facing the ophthalmic device main body such as the measurement head 14 (objective lens 43 described later).

[0028] In addition, the face support unit 12 is provided with an external fixation lamp 15. The external fixation lamp 15 has a light source that emits fixation light, and the position of the light source and the emission direction of the fixation light can be adjusted as desired. This external fixation lamp 15 is used for external fixation. External fixation is a fixation method in which the position of the light source of the external fixation lamp 15 is adjusted to rotate the subject's eye E (see FIG. 3) in any direction, or to rotate it more than in internal fixation, or to adjust the direction of the subject's eye E by guiding the line of sight of the subject's eye E or the fellow eye when internal fixation cannot be performed.

[0029] The stand 13 is provided so as to be movable in the X direction and the Z direction (front-back and left-right directions) with respect to the base 11. An operation unit 16 is provided on the stand 13. In addition, a measuring head 14 is provided on the stand 13 so as to be movable in the Y direction.

[0030] Further, the base 13 is provided with an electric drive mechanism 17. The electric drive mechanism 17 is a known actuator such as a motor drive mechanism, and moves the base 13 in the XZ directions and moves the measurement head 14 in the Y direction under the control of an arithmetic and control unit 22 (see FIG. 3) described later. This allows the measurement head 14 to move relatively in the XYZ directions with respect to the subject's eye E.

[0031] The operation unit 16 is provided on the stand 13 at a position on the rear side (examiner side) in the Z direction of the measurement head 14. The operation unit 16 is provided with an operation lever 16a in addition to operation buttons for performing various operations of the ophthalmologic apparatus 10 (switching between imaging modes, etc.).

[0032] The operating lever 16a is an operating member for manually moving the measuring head 14 in each of the X, Y and Z directions. For example, when the operating lever 16a is tilted in the Z direction (front-back direction) or the X direction (left-right direction), the measuring head 14 is moved in the Z direction or the X direction by the above-mentioned electric drive mechanism 17. When the operating lever 16a is rotated around its longitudinal axis, the measuring head 14 is moved in the Y direction (up-down direction) by the electric drive mechanism 17 according to the direction of the rotation.

[0033] The measurement head 14 has a built-in fundus camera unit 14a and an OCT unit 14b shown in Fig. 3 described later. A monitor 18 is provided on the rear side (examiner side) of the measurement head 14 in the Z direction. A lens housing section 19 is provided on the front side (subject side) of the measurement head 14 in the Z direction.

[0034] For example, a touch panel type liquid crystal display device is used as the monitor 18. This monitor 18 displays a screen of various photographed data of the subject's eye E (see FIG. 3), an input screen for various setting operations, etc. Note that the monitor 18 functions as the above-mentioned operation unit 16 when displaying the input screen.

[0035] The lens housing portion 19 houses an objective lens 43 which constitutes a part of the fundus camera unit 14a (see FIG. 3) and has an optical axis OA (see FIG. 3) parallel to the Z direction.

[0036] Although not shown, the lens housing section 19 is provided with a plurality of fixation holes (also called fixation lights) that are arranged at equal intervals along the circumferential direction so as to surround the objective lens 43. Each fixation hole is used for peripheral fixation and imaging of the angle (the edge of the iris Er in FIG. 5) of the subject's eye E (see FIG. 3), and selectively emits fixation light in the Z direction in response to an operation on the operation section 16. Note that peripheral fixation is a fixation method in which each fixation hole is selectively lit to largely rotate the subject's eye E in a desired direction.

[0037] Furthermore, a stereo camera 20 is provided in front of the measurement head 14 and in the vicinity of the lens housing portion 19. The stereo camera 20 has a first camera 20a and a second camera 20b. The first camera 20a and the second camera 20b are arranged to sandwich the objective lens 43 from the left and right. The first camera 20a and the second camera 20b will be described later.

[0038] [Measuring head] 3 is a schematic diagram showing an example of the configuration of the measurement head 14 of the ophthalmologic apparatus 10. As shown in FIG. 3, the measurement head 14 includes a fundus camera unit 14a, an OCT unit 14b, and a stereo camera 20, and is connected to an arithmetic and control unit 22.

[0039] The fundus camera unit 14a corresponds to the camera body of the present invention, and has an optical system similar to that of a conventional fundus camera. The fundus camera unit 14a irradiates the fundus Ef of the subject's eye E with photographing illumination light (such as flash light) through the objective lens 43, photographs the fundus Ef irradiated with the photographing illumination light, and outputs a fundus photographed image D1. The fundus camera unit 14a also photographs the anterior segment Ea of the subject's eye E through the objective lens 43, and outputs an anterior segment image D2, which is an observation image of the anterior segment Ea.

[0040] The OCT unit 14b acquires an OCT image of the fundus Ef through the objective lens 43 and a part of the optical system of the fundus camera unit 14a.

[0041] The arithmetic and control unit 22 is housed, for example, in the base 11 or the measuring head 14, and is an arithmetic processing device such as a computer that executes various arithmetic processes and control processes.

[0042] <Fundus camera unit> The fundus camera unit 14a includes an illumination optical system 30 and an imaging optical system 50 as optical systems for acquiring a fundus image D1 and an anterior eye image D2.

[0043] The illumination optical system 30 irradiates the fundus Ef with illumination light (observation illumination light and photographing illumination light). The imaging optical system 50 guides fundus reflection light of the illumination light reflected by the fundus Ef to, for example, CMOS (Complementary Metal Oxide Semiconductor) type or CCD (Charge Coupled Device) type imaging elements 57, 60 to capture an image. The imaging optical system 50 also guides signal light output from the OCT optical system 80 (OCT unit 14b) to the fundus Ef, and also guides signal light that has passed through the fundus Ef to the OCT optical system 80.

[0044] The illumination optical system 30 includes an observation light source 31, a reflecting mirror 32, a condenser lens 33, a visible cut filter 34, an imaging light source 35, a mirror 36, relay lenses 37 and 38, an aperture 39, a small pupil diameter aperture 39A, an aperture switching mechanism 39B, a relay lens 40, an aperture mirror 41, a dichroic mirror 42, and an objective lens 43.

[0045] The imaging optical system 50 includes, in addition to the objective lens 43, dichroic mirror 42, and aperture mirror 41 described above, a focusing lens 51, a mirror 52, a half mirror 53, an optotype display unit 54, a dichroic mirror 55, a condensing lens 56, an imaging element 57, a mirror 58, a condensing lens 59, and an imaging element 60.

[0046] The observation light source 31 is, for example, a halogen lamp or an LED (light emitting diode), and emits observation illumination light. The observation illumination light emitted from the observation light source 31 is reflected by a reflecting mirror 32, passes through a condenser lens 33, and becomes near-infrared light by passing through a visible light cut filter 34. The observation illumination light that passes through the visible light cut filter 34 is once focused near the imaging light source 35, reflected by a mirror 36, and passes through relay lenses 37 and 38, an aperture 39 (or a small pupil diameter aperture 39A), and a relay lens 40. The observation illumination light is then reflected by the peripheral portion (the area around the hole) of the aperture mirror 41, passes through a dichroic mirror 42, and is further refracted by an objective lens 43 to illuminate the fundus Ef.

[0047] The fundus reflected light of the observation illumination light is refracted by the objective lens 43, passes through the dichroic mirror 42, a hole formed in the central region of the aperture mirror 41, and the focusing lens 51, and is then reflected by the mirror 52. Furthermore, this fundus reflected light passes through the half mirror 53, and is reflected by the dichroic mirror 55, and is imaged on the light receiving surface of the image sensor 57 by the condenser lens 56. The image sensor 57 captures (receives) the fundus reflected light and outputs an observation image of the fundus Ef to the arithmetic and control unit 22 described below. The arithmetic and control unit 22 causes the monitor 18 to display the observation image of the fundus Ef.

[0048] When the focus of the imaging optical system 50 is adjusted to the anterior eye Ea of the subject's eye E, the imaging element 57 captures the anterior eye reflected light (corneal reflected light) and outputs the anterior eye image D2 to the arithmetic and control unit 22. In this case, the arithmetic and control unit 22 causes the monitor 18 to display the anterior eye image D2.

[0049] The imaging light source 35 is, for example, a xenon lamp or an LED light source, and emits imaging illumination light (flash light) including at least light in the visible wavelength range. The imaging illumination light emitted from the imaging light source 35 is irradiated onto the fundus Ef through the same path as the observation illumination light described above. The fundus reflection light of the imaging illumination light is guided to the dichroic mirror 55 through the same path as the fundus reflection light of the observation illumination light, and after transmitting through this dichroic mirror 55, is reflected by a mirror 58 and is imaged by a condenser lens 59 on the light receiving surface of the image sensor 60.

[0050] The imaging element 60 captures (receives) the fundus reflected light and outputs a fundus image D1 to the arithmetic and control unit 22. The arithmetic and control unit 22 displays the fundus image D1 based on the imaging signal output from the imaging element 60 on the monitor 18. Note that the monitor 18 displaying the various observation images and the monitor 18 displaying the fundus image D1 may be the same or different from each other.

[0051] The small pupil diameter diaphragm 39A corresponds to a small pupil diameter eye with a pupil diameter d (see FIG. 5) smaller than a standard pupil diameter (e.g., 3 to 4 mm) (e.g., less than 2 mm), and is held removably in the optical path of each illumination light by the diaphragm switching mechanism 39B. The small pupil diameter diaphragm 39A is formed with an opening diameter smaller than that of the standard diaphragm 39. The definitions of a small pupil diameter and a small pupil diameter eye, and the specific shape and function of the small pupil diameter diaphragm 39A are publicly known techniques, so a description thereof will be omitted here (see Patent Document 2 and JP 2013-165819 A). By inserting the small pupil diameter diaphragm 39A into the optical path of each illumination light, the fundus Ef can be illuminated with each illumination light even if the subject eye E is a small pupil diameter eye.

[0052] The aperture switching mechanism 39B is a known actuator such as a motor drive mechanism that selectively inserts (places) the aperture 39 and the small pupil diameter aperture 39A in the optical path of the illumination light under the control of the arithmetic and control unit 22. In the first embodiment, the arithmetic and control unit 22 drives the aperture switching mechanism 39B in response to a switching operation input to the operation unit 16, and is capable of selectively placing the aperture 39 and the small pupil diameter aperture 39A on the optical path of the illumination light. Note that in the first embodiment, the small pupil diameter aperture 39A and the aperture switching mechanism 39B may be omitted.

[0053] The target display unit 54 is used for internal fixation by projecting fixation light of a fixation target (bright spot image) onto the subject's eye E through the objective lens 43, and may be, for example, a dot matrix liquid crystal display (LCD: Liquid Crystal Display) or a matrix light emitting diode (LED). The target display unit 54 displays the fixation target. The target display unit 54 can arbitrarily set the display mode (shape, etc.) and display position of the fixation target.

[0054] A part of the fixation light of the fixation target displayed on the target display unit 54 is reflected by the half mirror 53, and then passes through the mirror 52, the focusing lens 51, the dichroic mirror 55, the hole of the aperture mirror 41, the dichroic mirror 42, and the objective lens 43 to be projected onto the subject's eye E. As a result, the fixation target and the visual acuity measuring target are presented to the subject's eye E through the objective lens 43.

[0055] The fundus camera unit 14a includes a focusing optical system 70. The focusing optical system 70 generates a split index for focusing on the fundus Ef. The focusing optical system 70 includes an LED 71, a relay lens 72, a split index plate 73, a two-hole aperture 74, a mirror 75, a condenser lens 76, and a reflecting rod 77 in addition to the objective lens 43, the dichroic mirror 42, and the aperture mirror 41 described above.

[0056] The reflecting surface of the reflecting rod 77 is set on the optical path of the illumination optical system 30 when focus adjustment is performed by the focus optical system 70. The focusing light emitted from the LED 71 passes through the relay lens 72 and is separated into two light beams by the split index plate 73, and then passes through the two-hole diaphragm 74, the mirror 75, and the condenser lens 76 to form an image on the reflecting surface of the reflecting rod 77, and is reflected by this reflecting surface toward the relay lens 40. The focusing light further passes through the relay lens 40, the aperture mirror 41, the dichroic mirror 42, and the objective lens 43 to be projected onto the fundus Ef.

[0057] The fundus reflection light of the focusing light passes through the objective lens 43, the dichroic mirror 42, and the hole of the aperture mirror 41, and after a part of it passes through the dichroic mirror 55, it passes through the focusing lens 51, the mirror 52, the half mirror 53, the dichroic mirror 55, and the condenser lens 56 and is imaged by the image sensor 57. The image sensor 57 images the fundus reflection light of the focusing light and outputs an image signal. As a result, the split index is displayed on the monitor 18 together with the observation image of the fundus Ef. The arithmetic and control unit 22 automatically performs focusing by analyzing the position of the split index and moving the focusing lens 51, etc., as in the conventional case. The examiner may also manually perform focusing based on the split index displayed on the monitor 18.

[0058] The dichroic mirror 42 branches the optical path of the OCT optical system 80 from the optical path for fundus imaging. The dichroic mirror 42 reflects light in the wavelength band used for OCT measurement and transmits light for fundus imaging. The optical path of the OCT optical system 80 includes, in order from the OCT unit 14b side, a collimator lens unit 81, an optical path length changer 82, a galvano scanner 83, a focusing lens 84, a mirror 85, and a relay lens 86.

[0059] The optical path length changing unit 82 includes, for example, a corner cube and a mechanism for moving the corner cube. The optical path length changing unit 82 is movable in the direction of the arrow shown in the figure, and changes the optical path length of the OCT optical system 80. This change in the optical path length is used for correcting the optical path length according to the axial length of the subject's eye E, adjusting the interference state, and the like.

[0060] The galvano scanner 83 changes the traveling direction of the signal light passing through the optical path of the OCT optical system 80. This allows the fundus Ef to be scanned with the signal light. The galvano scanner 83 includes, for example, a galvano mirror that scans the signal light in the X direction, a galvano mirror that scans the signal light in the Y direction, and a mechanism for independently driving these. This allows the signal light to be scanned in any direction on the XY plane.

[0061] <OCTユニット> The OCT unit 14b includes an interference optical system used to acquire an OCT image of the fundus Ef. As with known OCT devices, the OCT unit 14b splits low-coherence light into reference light and signal light, generates interference light by causing the signal light that has passed through the fundus Ef to interfere with the reference light that has passed through a reference light path, and detects the spectral components of the interference light. The detection result (detection signal) by the OCT unit 14b is output to the arithmetic and control unit 22. Note that the specific configuration of the OCT unit 14b is a known technique (see, for example, Patent Document 1 above), and therefore a detailed description thereof will be omitted here.

[0062] <Stereo camera> The first camera 20a and the second camera 20b constituting the stereo camera 20 simultaneously (including substantially simultaneously) and continuously capture (take video) the anterior eye portion Ea from different directions, that is, from the left and right directions in this embodiment, and output the anterior eye portion images D2 to the arithmetic and control unit 22. The symbol OB in the figure indicates the imaging optical axis of the first camera 20a and the second camera 20b.

[0063] [Calculation and control unit] Fig. 4 is a functional block diagram of the arithmetic control unit 22 of the ophthalmologic apparatus 10 of the first embodiment. As shown in Fig. 4, the arithmetic control unit 22 includes a general control unit 90, a storage unit 92, an image forming unit 94, and a data processing unit 96. The arithmetic control unit 22 is also connected to the fundus camera unit 14a, the OCT unit 14b, the operation unit 16, the electric drive mechanism 17, the monitor 18, the stereo camera 20, and the like.

[0064] The storage unit 92 stores the control program executed by the general control unit 90, as well as image data of the fundus image D1 and image data of the OCT image. The storage unit 92 also stores an imaging threshold T1 determined by a threshold determination unit 106, which will be described later. The storage unit 92 may be constructed in an external server (database) instead of inside the ophthalmologic apparatus 10.

[0065] The image forming unit 94 is used to obtain an OCT image of the fundus Ef of the subject's eye E together with the OCT unit 14b, and forms an OCT image of the fundus Ef by analyzing a detection signal input from the OCT unit 14b. Note that a specific method for forming the OCT image is similar to that of a conventional OCT device, and therefore a description thereof will be omitted here. The data processing unit 96 performs image processing and the like on the OCT image formed by the image forming unit 94 and the fundus photographed image D1 obtained by the fundus camera unit 14a.

[0066] The overall control unit 90 overall controls the operation of each unit of the ophthalmologic apparatus 10. Furthermore, the overall control unit 90 judges whether or not the pupil Ep (see FIG. 5) of the subject's eye E is miotic based on the anterior eye image D2 before the fundus is photographed by the fundus camera unit 14a. If the overall control unit 90 judges that the pupil Ep is miotic, the overall control unit 90 waits to perform fundus photography of the subject's eye E until the miosis subsides, and performs photography control to perform fundus photography of the subject's eye E when the overall control unit 90 judges that the miosis of the pupil Ep has subsided. Note that in the first embodiment, in order to perform fundus photography of a normal eye with the above-mentioned standard pupil diameter, not a small pupil diameter eye, as the subject's eye E, the above-mentioned photography control is performed when photographing the fundus from the second time onwards in the continuous photography mode or the right and left eye photography mode.

[0067] The functions of the general control unit 90 are realized by using various processors. The various processors include a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), and a programmable logic device (e.g., simple programmable logic devices (SPLD), complex programmable logic devices (CPLD), and field programmable gate arrays (FPGA)). The various functions of the general control unit 90 may be realized by one processor, or may be realized by multiple processors of the same type or different types.

[0068] The general control unit 90 functions as an anterior eye image acquisition unit 100, an alignment control unit 102, a pupil diameter detection unit 104, a threshold determination unit 106, and an imaging control unit 108 during fundus imaging of the subject's eye E (continuous imaging mode, left and right eye imaging mode). Note that what is described as a "part" of the arithmetic and control unit 22 may be a "circuit", a "device", or a "equipment". In other words, what is described as a "part" may be firmware, software, hardware, or a combination of these. Also, in FIG. 4, only the functions of the general control unit 90 related to fundus imaging of the subject's eye E are illustrated, and other functions are well-known techniques and therefore are not specifically illustrated.

[0069] The anterior eye image acquisition unit 100 is connected via a wired or wireless connection to at least one of the fundus camera unit 14a (image sensor 57) and the stereo camera 20 via a communication interface not shown, and acquires an anterior eye image D2 from at least one of the fundus camera unit 14a and the stereo camera 20.

[0070] The anterior eye image D2 is used for auto-alignment of the measurement head 14 with respect to the subject's eye E. The anterior eye image D2 is also used to confirm the size of the pupil Ep (see FIG. 5) of the subject's eye E before fundus photography by the fundus camera unit 14a. Note that in this embodiment, the description will be given assuming that auto-alignment and confirmation of the size of the pupil Ep of the subject's eye E before fundus photography are performed based on the anterior eye image D2 photographed by the stereo camera 20. When a measurement start operation is inputted at the operation unit 16, the anterior eye image acquisition unit 100 repeatedly acquires the anterior eye image D2 from the stereo camera 20 until fundus photography of the subject's eye E is completed.

[0071] The alignment control unit 102 calculates the relative position (three-dimensional position) of the subject's eye E with respect to the measurement head 14 based on the anterior eye image D2 acquired by the anterior eye image acquisition unit 100 from the stereo camera 20 in response to a measurement start operation (see Patent Document 3 above). Next, the alignment control unit 102 drives the electric drive mechanism 17 based on the calculation result of the relative position of the subject's eye E to perform auto-alignment of the measurement head 14 with respect to the subject's eye E.

[0072] When the fundus photography mode is the continuous photography mode or the left and right eye photography mode, the pupil diameter detection unit 104 operates at least before the first fundus photography of the subject eye E by the fundus camera unit 14a and before the second or subsequent fundus photography.

[0073] Note that "before the first fundus photography" refers to the period until the first fundus photography of the subject's eye E is started, regardless of the type of photography mode. In addition, "before the second or subsequent fundus photography" in the continuous photography mode refers to the period from the completion of the Nth fundus photography to the start of the N+1th fundus photography, where "N" is any natural number. Furthermore, "before the second or subsequent fundus photography" in the left and right eye photography mode refers to the period from the completion of the fundus photography of one of the left and right eyes to the start of the fundus photography of the other eye.

[0074] Fig. 5 is an explanatory diagram for explaining detection of a pupil diameter d by the pupil diameter detection unit 104. As shown in Fig. 5 and the already described Fig. 4, the pupil diameter detection unit 104 detects a pupil diameter d, which is the diameter of the pupil Ep of the subject's eye E, based on an anterior eye image D2 acquired from at least one of the first camera 20a and the second camera 20b of the stereo camera 20.

[0075] For example, the pupil diameter detection unit 104 detects the pupil margin Eb from the anterior eye image D2 acquired from at least one of the first camera 20a and the second camera 20b. This pupil margin Eb can be detected based on the difference in brightness between the pupil Ep and the iris Er in the anterior eye image D2.

[0076] Next, the pupil diameter detection unit 104 detects (calculates) the pupil diameter d by calculating an ellipse approximation and center coordinates of the pupil margin Eb based on the detection result of the pupil margin Eb from the anterior eye image D2. Note that the method of detecting the pupil diameter d from the anterior eye image D2 captured by the stereo camera 20 is a publicly known technique, and therefore a detailed description thereof will be omitted here (see, for example, JP 2019-62982 A).

[0077] The pupil diameter detection unit 104 detects the pupil diameter d at least once before the first fundus photography of the subject's eye E, and repeatedly detects the pupil diameter d a plurality of times before the second or subsequent fundus photography. This makes it possible to detect a change in the pupil diameter d of the subject's eye E in real time, at least before the second or subsequent fundus photography of the subject's eye E.

[0078] The threshold determination unit 106 determines the photographing threshold T1 (corresponding to the first threshold of the present invention) which is the lower limit of the pupil diameter d at which a good fundus photographed image D1 can be obtained, based on the pupil diameter d detected by the pupil diameter detection unit 104 before the first fundus photographing of the subject's eye E. The photographing threshold T1 is a threshold for determining whether or not the second or subsequent fundus photographing of the subject's eye E is performed. Here, since the subject's eye E in this embodiment is a normal eye, the pupil Ep does not contract before the first fundus photographing, that is, in a state where the subject's eye E has not been irradiated with the photographing illumination light (flash light) even once, and the pupil diameter d is also a size at which a good fundus photographed image D1 can be obtained. Therefore, the pupil diameter d of the subject's eye E before the first fundus photographing can be used as a judgment criterion (photographing threshold T1) for judging whether or not the pupil Ep has contracted.

[0079] Specifically, the threshold determination unit 106 determines the pupil diameter d detected by the pupil diameter detection unit 104 before the first fundus photography of the subject's eye E as the photography threshold T1 as it is. When the pupil diameter detection unit 104 detects the pupil diameter d multiple times, the threshold determination unit 106 may determine the minimum value, average value, or the like as the photography threshold T1 as it is.

[0080] Furthermore, the threshold determination unit 106 may determine, as the photographing threshold T1, a value that is a certain percentage smaller than the pupil diameter d detected by the pupil diameter detection unit 104 before the first fundus photographing of the subject's eye E, taking into consideration a detection error of the pupil diameter d by the pupil diameter detection unit 104 and a fluctuation in the pupil diameter d of the subject's eye E. By thus determining the photographing threshold T1 based on the pupil diameter d detected by the pupil diameter detection unit 104, the threshold determination unit 106 can individually determine the photographing threshold T1 corresponding to the subject even if there is an individual difference in the pupil diameter d of each subject.

[0081] 4, the photography control unit 108 controls the fundus camera unit 14a and the OCT 14b to control photography of a fundus image D1 and an OCT image of the fundus Ef of the subject's eye E. When the photography mode for fundus photography is the normal mode, the photography control unit 108 drives the fundus camera unit 14a after completion of auto-alignment to perform fundus photography of the subject's eye E, thereby obtaining a fundus image D1. Note that photography control of the fundus camera unit 14a by the photography control unit 108 when the photography mode is the continuous photography mode or the left and right eye photography mode will be described later.

[0082] When performing OCT measurement of the fundus Ef, the imaging control unit 108 drives the OCT optical system 80, the OCT unit 14b, the image forming unit 94, etc. after completing auto-alignment to obtain an OCT image of the fundus Ef.

[0083] FIG. 6 is an explanatory diagram for explaining the photographing control of the fundus camera unit 14a by the photographing control unit 108 in the continuous photographing mode.

[0084] As shown by reference symbol 6A in Fig. 6, when the continuous photographing mode is selected as the photographing mode, the photographing control unit 108 executes the first fundus photographing of the subject's eye E (first photographing of the present invention) by the fundus camera unit 14a after the completion of auto-alignment. As described above, since the subject's eye E is a normal eye, the pupil Ep does not constrict during the first fundus photographing, and the fundus photographing can be performed in the same manner as in the normal mode. Then, when the first fundus photographing of the subject's eye E is executed, the pupil Ep constricts due to irradiation with the photographing illumination light (flash light).

[0085] 6, before the second fundus photography of the subject's eye E, the photography control unit 108 refers to the photography threshold T1 in the storage unit 92 based on the detection result of the pupil diameter d repeatedly detected by the pupil diameter detection unit 104, and determines whether the pupil diameter d of the subject's eye E is equal to or greater than the photography threshold T1. If the pupil diameter d is less than the photography threshold T1, the photography control unit 108 waits to execute the second fundus photography. In this case, the photography control unit 108 waits until the pupil diameter d repeatedly detected by the pupil diameter detection unit 104 becomes equal to or greater than the photography threshold T1.

[0086] 6, when the pupil diameter d of the subject's eye E repeatedly detected by the pupil diameter detection unit 104 becomes equal to or larger than the photographing threshold T1, the photographing control unit 108 executes a second fundus photographing of the subject's eye E (second photographing of the present invention) by the fundus camera unit 14a. This allows the second fundus photographing of the subject's eye E by the fundus camera unit 14a to be automatically executed in accordance with the convergence of the miosis of the pupil Ep of the subject's eye E.

[0087] Thereafter, for the third and subsequent fundus photographs of the subject eye E, the photographing control unit 108 similarly waits until the pupil diameter d of the subject eye E, which is repeatedly detected by the pupil diameter detection unit 104, becomes equal to or greater than the photographing threshold value T1, and when the pupil diameter d becomes equal to or greater than the photographing threshold value T1, performs fundus photographing of the subject eye E using the fundus camera unit 14a.

[0088] FIG. 7 is an explanatory diagram for explaining the photographing control of the fundus camera unit 14a by the photographing control unit 108 in the left and right eye photographing mode.

[0089] As shown by reference symbol 7A in FIG. 7, when the right and left eye photographing mode is selected as the photographing mode, the photographing control unit 108 executes the first fundus photographing of the subject's eye E by the fundus camera unit 14a, that is, the fundus photographing of one of the left and right eyes (for example, the right eye) (corresponding to the first photographing of the present invention) after the completion of the auto-alignment. As described above, since the subject's eye E is a normal eye, the fundus photographing can be performed in the same manner as the first fundus photographing in the continuous photographing mode. Then, when the fundus photographing of one of the left and right eyes is executed, the pupil Ep of one of the left and right eyes contracts due to the irradiation of the photographing illumination light (flash light), and the pupil Ep of the other of the left and right eyes (for example, the left eye) also contracts in conjunction with this contraction. Also, when the fundus photographing of one of the left and right eyes is executed, the alignment control unit 102 executes the auto-alignment of the measurement head 14 with respect to the other of the left and right eyes.

[0090] 7, after completion of auto-alignment and before photographing the other of the left and right eyes, the photographing control unit 108 determines whether or not the pupil diameter d of the other of the left and right eyes is equal to or greater than the photographing threshold value T1, similarly to the second and subsequent fundus photographing in the continuous photographing mode, based on the detection result of the pupil diameter d repeatedly detected by the pupil diameter detection unit 104. If the pupil diameter d of the other of the left and right eyes is less than the photographing threshold value T1, the photographing control unit 108 waits to photograph the other of the fundus until the pupil diameter d becomes equal to or greater than the photographing threshold value T1.

[0091] 7, when the pupil diameter d repeatedly detected by the pupil diameter detection unit 104 becomes equal to or larger than the photographing threshold T1, the photographing control unit 108 executes a second fundus photographing of the subject eye E by the fundus camera unit 14a, that is, photographing the other fundus of the left or right eye (corresponding to the second photographing of the present invention). This allows the fundus camera unit 14a to automatically photograph the other fundus in accordance with the convergence of the pupil constriction of the other of the left or right eyes.

[0092] [Function of the Ophthalmic Apparatus of the First Embodiment] 8 corresponds to a control method of the fundus camera of the present invention, and is a flowchart showing a flow of fundus photographing processing of the subject's eye E by the ophthalmologic apparatus 10 of the first embodiment. Note that, here, the explanation will be given taking as an example a case where the continuous photographing mode or the right and left eye photographing mode is selected as the photographing mode for fundus photographing.

[0093] After the subject's face is supported by the face support unit 12, the examiner inputs an operation to start photographing with the operation unit 16 (step S1), and the general control unit 90 functions as an anterior eye image acquisition unit 100, an alignment control unit 102, a pupil diameter detection unit 104, a threshold determination unit 106, and an photographing control unit 108. Then, the anterior eye image acquisition unit 100 starts continuous photographing of the anterior eye Ea of the subject's eye E by the stereo camera 20. As a result, the anterior eye image acquisition unit 100 repeatedly acquires anterior eye images D2 from the stereo camera 20 (step S2).

[0094] Then, the alignment control unit 102 detects the relative position of the test eye E with respect to the measurement head 14 based on the anterior eye image D2 acquired by the anterior eye image acquisition unit 100 from the stereo camera 20, and then drives the electric drive mechanism 17 to perform auto-alignment of the measurement head 14 with respect to the test eye E (step S3).

[0095] Furthermore, the pupil diameter detection unit 104 detects the pupil diameter d of the subject's eye E at least once (step S5, corresponding to the pupil diameter detection step of the present invention) based on the anterior eye image D2 acquired by the anterior eye image acquisition unit 100 (step S4, corresponding to the anterior eye image acquisition step of the present invention). Then, the threshold determination unit 106 determines the photographing threshold T1 based on the detection result of the pupil diameter d by the pupil diameter detection unit 104 and stores it in the storage unit 92 (step S6). Note that the timing of steps S4 and S5 is not particularly limited as long as it is before the first fundus photographing of the subject's eye E by the fundus camera unit 14a, and may be performed before or during auto-alignment.

[0096] When the auto-alignment and storage of the photographing threshold T1 are completed, as shown by reference numeral 6A in Fig. 6 and reference numeral 7A in Fig. 7, the photographing control unit 108 causes the fundus camera unit 14a to perform the first fundus photographing of the subject's eye E (step S7). As a result, the fundus camera unit 14a irradiates the fundus Ef of the subject's eye E with photographing illumination light (flash light) and photographs the fundus Ef, and outputs the fundus photographed image D1 to the arithmetic and control unit 22. At this time, since the subject's eye E is a normal eye and has not contracted before the first fundus photographing, a good fundus photographed image D1 can be obtained.

[0097] When the first fundus photography of the test eye E is performed, as shown by reference numeral 6B in Figure 6 and reference numeral 7B in Figure 7, the pupil Ep of the test eye E (both eyes) constricts due to the irradiation of the photography illumination light from the fundus camera unit 14a.

[0098] When the photographing mode is the continuous photographing mode, after the first fundus photographing of the subject's eye E is completed, the anterior eye image acquiring unit 100 acquires an anterior eye image D2 from the stereo camera 20 (step S8, which corresponds to the anterior eye image acquiring step of the present invention), and the pupil diameter d is detected by the pupil diameter detecting unit 104 (step S9, which corresponds to the pupil diameter detecting step of the present invention). Diameter On the other hand, when the fundus photography mode is the right / left eye photography mode, the alignment control unit 102 performs auto-alignment of the measurement head 14 with respect to the other of the right and left eyes in parallel with the above-mentioned processes of steps S8 and S9, although not shown in the figure.

[0099] Then, the photographing control unit 108 goes into a standby state until the pupil diameter d repeatedly detected by the pupil diameter detection unit 104 becomes equal to or greater than the photographing threshold T1, and repeat control is performed in which the processes of the above-mentioned steps S8 and S9 are repeatedly executed (NO in step S10).

[0100] Next, as shown by reference numeral 6C in FIG. 6 and reference numeral 7C in FIG. 7, when the pupil diameter d repeatedly detected by the pupil diameter detection unit 104 becomes equal to or greater than the photographing threshold value T1, the photographing control unit 108 causes the fundus camera unit 14a to perform a second fundus photographing of the subject's eye E (the other of the right and left eyes) (YES in step S10, step S11). As a result, the fundus camera unit 14a irradiates the fundus Ef of the subject's eye E with photographing illumination light (flash light) and photographs the fundus Ef, and outputs a fundus photographed image D1 to the arithmetic control unit 22. The second fundus photographing is automatically performed by the fundus camera unit 14a in accordance with the convergence of the pupil contraction of the subject's eye E, so that a good fundus photographed image D1 can be obtained. Note that step S11 corresponds to the photographing control step of the present invention.

[0101] Hereinafter, when performing the third or subsequent fundus photographing of the subject's eye E (continuous photographing mode), the processes from step S8 to step S11 are repeatedly executed (step S12).

[0102] [Effects of the first embodiment] As described above, in the first embodiment, in the second and subsequent fundus photographs in which miosis of the subject's eye E occurs, fundus photographing is put on hold until the pupil diameter d of the subject's eye E becomes equal to or larger than the photographing threshold T1 based on the detection result of the pupil diameter detection unit 104, and fundus photographing can be performed when the pupil diameter d becomes equal to or larger than the photographing threshold T1. As a result, fundus photographing can be reliably performed in a state in which the pupil Ep of the subject's eye E is not miotically constricted, and a good fundus image D1 can be obtained.

[0103] [Second embodiment] Next, an ophthalmic apparatus 10 according to a second embodiment of the present invention will be described. In the ophthalmic apparatus 10 according to the first embodiment, when the pupil Ep of the subject's eye E is constricted by irradiation with the photographing illumination light, fundus photography is put on hold until the pupil diameter d of the subject's eye E becomes equal to or larger than the photographing threshold T1. However, depending on the subject's eye E (subject), it may take a long time for the pupil Ep to stop constricting. Therefore, in the ophthalmic apparatus 10 according to the second embodiment, when it takes a long time for the pupil Ep to stop constricting by irradiation with the photographing illumination light, the small pupil diameter aperture 39A is used to photograph the fundus of the subject's eye E.

[0104] The ophthalmic device 10 of the second embodiment has basically the same configuration as the ophthalmic device 10 of the first embodiment, except for some differences in the functions of the shooting control unit 108. Therefore, parts that are the same in function or configuration as the first embodiment are given the same symbols and their descriptions are omitted.

[0105] 9 is a flowchart showing a flow of fundus photographing processing of the subject's eye E by the ophthalmologic apparatus 10 of the second embodiment. Note that the processing from step S1 to step S9 is the same as that of the first embodiment described with reference to FIG. 8, and therefore a detailed description thereof will be omitted.

[0106] 9, in the second embodiment, if the pupil diameter d repeatedly detected by the pupil diameter detection unit 104 after the first fundus photographing of the subject's eye E is less than the photographing threshold T1, the photographing control unit 108 waits for the execution of the second fundus photographing of the subject's eye E (NO in step S10). Then, the photographing control unit 108 starts measuring the waiting time. If the pupil diameter d of the subject's eye E becomes equal to or greater than the photographing threshold T1 within a predetermined fixed time based on the detection result of the pupil diameter detection unit 104, the photographing control unit 108 executes the processes of steps S11 and S12 as in the first embodiment (see FIG. 8) (NO in step S10A).

[0107] On the other hand, when the pupil diameter d is less than the photographing threshold T1 even after a predetermined time has elapsed based on the detection result of the pupil diameter detection unit 104, the photographing control unit 108 drives the aperture switching mechanism 39B to insert the small pupil diameter aperture 39A into the optical path of the illumination light (YES in step S10A, step S10B). As a result, even in a state in which the pupil Ep of the subject eye E has not yet contracted, the small pupil diameter aperture 39A corresponding to the small pupil diameter eye can be used to illuminate the fundus Ef with each illumination light (photographing illumination light, etc.).

[0108] Next, the photography control unit 108 controls the fundus camera unit 14a to perform a second fundus photography of the subject's eye E (step S11). In this case, the photography control unit 108 functions as the first special photography control unit of the present invention. Since the fundus Ef irradiated with the photography illumination light by the small pupil diameter diaphragm 39A can be photographed by the fundus camera unit 14a, a good fundus photographed image D1 can be obtained. When the fundus photography is completed, the photography control unit 108 drives the diaphragm switching mechanism 39B to retract the small pupil diameter diaphragm 39A from the optical path of the illumination light and insert the diaphragm 39 into this optical path.

[0109] Hereinafter, when the third or subsequent fundus photographing (continuous photographing mode) of the subject's eye E is performed, the above-described series of processes are repeatedly executed (step S12).

[0110] As described above, in the second embodiment, if it takes a long time for the miosis of the pupil Ep of the test eye E caused by the irradiation of the photographing illumination light to subside, the fundus image D1 can be captured in a short time by performing fundus photography of the test eye E with the small pupil diameter aperture 39A inserted in the optical path of the illumination light.

[0111] In the second embodiment, the small pupil diameter diaphragm 39A is inserted (placed) in the optical path of the illumination light when it takes time for the miosis of the pupil Ep of the subject's eye E to subside, but the small pupil diameter diaphragm 39A in the second embodiment is not particularly limited as long as it has a diameter at least smaller than that of the diaphragm 39, and a diaphragm having a diameter larger than that of a general small pupil diameter diaphragm 39A may be used. Also, a variable diaphragm (including a liquid crystal shutter) capable of adjusting the diaphragm diameter according to the amount of miosis of the pupil Ep of the subject's eye E may be used as the small pupil diameter diaphragm 39A in the second embodiment.

[0112] [Third embodiment] 10 is a functional block diagram of the arithmetic control unit 22 of the ophthalmic apparatus 10 of the third embodiment. The ophthalmic apparatus 10 of each of the above embodiments photographs the fundus of a normal eye as the subject's eye E, but the ophthalmic apparatus 10 of the third embodiment photographs the fundus of an eye with a small pupil as the subject's eye E. Specifically, when photographing the fundus of an eye with a small pupil, the ophthalmic apparatus 10 of the third embodiment photographs the fundus of the subject's eye E in a state in which a small pupil aperture 39A is automatically inserted into the optical path of the illumination light.

[0113] The ophthalmic apparatus 10 of the third embodiment has basically the same configuration as the ophthalmic apparatus 10 of each of the above-mentioned embodiments, except that the general control unit 90 functions as a small pupil diameter determination unit 109, the function of the imaging control unit 108 is partially different, and a determination threshold value T2 is stored in the storage unit 92. For this reason, the same reference numerals are used to designate the same components in function or configuration as those of the above-mentioned embodiments, and the description thereof will be omitted.

[0114] The small pupil diameter determination unit 109 determines whether or not the subject eye E is a small pupil diameter eye before the first fundus photography of the subject eye E. The determination threshold T2 (corresponding to the second threshold of the present invention) is a threshold used for the determination by the small pupil diameter determination unit 109, and is set to a value smaller than the photography threshold T1, for example, 2 mm (see JP 2013-165819 A). Note that the determination threshold T2 may be prepared individually for each of various conditions related to the pupil diameter d of a small pupil diameter eye, such as the subject's age.

[0115] The imaging control unit 108 of the third embodiment functions as a second special imaging control unit of the present invention when the subject's eye E is a small pupil diameter eye, and performs fundus imaging of the subject's eye E using the small pupil diameter aperture 39A.

[0116] 11 is a flowchart showing a flow of fundus photographing processing of the subject's eye E by the ophthalmologic apparatus 10 of the third embodiment. Note that the processing from step S1 to step S5 is the same as that of the first embodiment described with reference to FIG. 8, and therefore a detailed description thereof will be omitted.

[0117] 11, before the first fundus photography of the subject's eye E, the small pupil diameter determination unit 109 determines whether or not the subject's eye E is a small pupil diameter eye by referring to the determination threshold T2 in the storage unit 92 based on the pupil diameter d detected by the pupil diameter detection unit 104 (step S5A). Specifically, the small pupil diameter determination unit 109 determines whether or not the subject's eye E is a small pupil diameter eye based on whether or not the pupil diameter d is less than the determination threshold T2.

[0118] When the small pupil diameter determination unit 109 determines that the subject eye E is a normal eye, the same processing as in each of the above-described embodiments (see FIGS. 8 and 9) is executed (NO in step S5A).

[0119] On the other hand, if the small pupil diameter determination unit 109 determines that the eye E is a small pupil diameter eye, the photographing control unit 108 drives the aperture switching mechanism 39B to insert the small pupil diameter aperture 39A into the optical path of the illumination light (YES in step S5A, step S5B). Then, the photographing control unit 108 causes the fundus camera unit 14a to perform a first fundus photograph of the eye E with the small pupil diameter aperture 39A inserted into this optical path (step S5C). By photographing the fundus of the eye E using the small pupil diameter aperture 39A corresponding to a small pupil diameter eye, a good fundus image D1 can be obtained even if the eye E is a small pupil diameter eye.

[0120] In addition, when the shooting mode is the left and right eye shooting mode, although not shown in the figure, when the first fundus photography of the test eye E is completed, the alignment control unit 102 performs automatic alignment of the measurement head 14 with the other of the left and right eyes.

[0121] Next, the photographing control unit 108 causes the fundus camera unit 14a to perform a second fundus photographing of the subject's eye E with the small pupil diameter diaphragm 39A inserted in the optical path of the illumination light (step S5D). As a result, a good fundus image D1 can be obtained, similar to the first fundus photographing.

[0122] Thereafter, when performing the third or subsequent fundus photographing of the subject's eye E (continuous photographing mode), the process of step S5D is repeatedly executed (step S5E).

[0123] As described above, in the third embodiment, it is determined whether the subject's eye E is a small pupil diameter eye based on the detection result of the pupil diameter detection unit 104, and if the subject's eye E is a small pupil diameter eye, the small pupil diameter aperture 39A is automatically inserted into the optical path of the illumination light, and then the fundus of the subject's eye E is photographed by the fundus camera unit 14a. As a result, even if the subject's eye E is a small pupil diameter eye, a good fundus photographed image D1 can be obtained. In addition, the small pupil diameter aperture 39A can be automatically inserted into the optical path of the illumination light without the examiner performing a switching operation on the operation unit 16.

[0124] [Fourth embodiment] 12 is a functional block diagram of the arithmetic control unit 22 of the ophthalmic apparatus 10 of the fourth embodiment. The ophthalmic apparatus 10 of each of the above embodiments waits to perform fundus photography until the pupil diameter d becomes equal to or larger than the photography threshold T1 in the second or subsequent fundus photography of the subject's eye E (excluding eyes with small pupil diameters), but in this case, it is unclear when the fundus photography will be performed. Therefore, the ophthalmic apparatus 10 of the fourth embodiment predicts the return time t required for the pupil diameter d of the subject's eye E, which has contracted due to irradiation with photography illumination light, to expand to the photography threshold T1, and notifies the user of this return time t.

[0125] The ophthalmic apparatus 10 of the fourth embodiment has basically the same configuration as the ophthalmic apparatus 10 of each of the above-mentioned embodiments, except that a speaker 119 is connected to the arithmetic control unit 22, and the general control unit 90 functions as a time prediction unit 110 and a notification control unit 112. Therefore, the same reference numerals are used for the same components in terms of function or configuration as those of the above-mentioned embodiments, and the description thereof will be omitted. In addition, the fourth embodiment will be described assuming that the subject's eye E is a normal eye.

[0126] Fig. 13 is an explanatory diagram for explaining a first example of prediction of return time t by the time prediction unit 110. As shown in Fig. 13 and the already described Fig. 12, when the first fundus photography of the subject's eye E is performed, the time prediction unit 110 predicts the return time t based on pupil diameter information 120 indicating the detection result of a new pupil diameter d by the pupil diameter detection unit 104, light source information 122 indicating the type of the photography light source 35, and subject information 124 indicating the age, disease, etc. of the subject.

[0127] The return time t varies depending on the degree of pupil constriction of the pupil Ep (pupil diameter d) at the time of the first fundus photographing of the subject's eye E, and for example, the greater the degree of pupil constriction, the longer the return time t. The return time t also varies depending on the type of the photographing light source 35 (type of photographing illumination light), and for example, the return time t may be longer or shorter for a specific photographing light source 35. The return time t also varies depending on the age and illness of the subject. For example, if the subject is elderly or has an illness such as eye fatigue, the return time t will be longer. Therefore, the time prediction unit 110 can predict the return time t based on the pupil diameter information 120, the light source information 122, and the subject information 124. The light source information 122 is stored in the storage unit 92 in advance, and the subject information 124 can be input via the operation unit 16 or acquired from a hospital database or the like.

[0128] For example, the time prediction unit 110 predicts the return time t by referring to a data table generated in advance based on the pupil diameter information 120, the light source information 122, and the subject information 124. The time prediction unit 110 may also predict the return time t using a trained model that receives the pupil diameter information 120, the light source information 122, and the subject information 124 as input and outputs the return time t. Then, the time prediction unit 110 outputs return time information 126 indicating the prediction result of the return time t to the notification control unit 112. The return time t predicted by the time prediction unit 110 (return time information 126) is updated every time the pupil diameter detection unit 104 detects a new pupil diameter d, that is, every time the pupil diameter information 120 is updated.

[0129] Note that the time prediction unit 110 of the present embodiment predicts the return time t based on the pupil diameter information 120, the light source information 122, and the subject information 124, but the light source information 122 and the subject information 124 are not essential, and the return time t may be predicted based only on the pupil diameter information 120. In other words, the time prediction unit 110 can predict the return time t based on at least the pupil diameter information 120.

[0130] FIG. 14 is an explanatory diagram for explaining a second example of prediction of the return time t by the time prediction unit 110. As shown in FIG. 14, the change in the pupil diameter d from when the pupil Ep of the subject's eye E contracts due to irradiation with the photographing illumination light until it returns to the original state is generally represented by the illustrated waveform W. Therefore, the time prediction unit 110 can calculate a predicted value PV (shown by a dotted line in the figure) of the change in the pupil diameter d over time by calculating the waveform W using a known fitting method or the like based on the change in the actual measured value MV of the pupil diameter d repeatedly detected by the pupil diameter detection unit 104 after the first photographing of the subject's eye E (shown by a solid line in the figure). As a result, the time prediction unit 110 can predict the return time t and output the return time information 126 to the notification control unit 112 before the pupil contraction of the pupil Ep of the subject's eye E subsides (before the pupil diameter d reaches the photographing threshold T1).

[0131] Fig. 15 is an explanatory diagram for explaining an example of display of return time information 126 on the monitor 18. As shown in Fig. 15 and the already described Figs. 12 and 13, the notification control unit 112, together with the monitor 18 and the speaker 119, constitutes the notification unit of the present invention. The notification control unit 112 outputs the return time information 126 input from the time prediction unit 110 to the monitor 18 and the speaker 119. As a result, the return time information 126 is displayed on the monitor 18 together with, for example, the anterior eye image D2 (moving image). In addition, the return time information 126 is output as sound from the speaker 119.

[0132] 16 is a flowchart showing a flow of fundus photographing processing of the subject's eye E by the ophthalmologic apparatus 10 of the fourth embodiment. Note that the processing from step S1 to step S9 is the same as that of the first embodiment (see FIG. 8) and the second embodiment (see FIG. 12) described above, and therefore a detailed description thereof will be omitted.

[0133] 16, after the first fundus photography of the subject's eye E by the fundus camera unit 14a is completed, if the pupil diameter d repeatedly detected by the pupil diameter detection unit 104 is less than the photography threshold T1 (NO in step S10), the time prediction unit 110 is activated. The time prediction unit 110 predicts the return time t based on the detection result of the pupil diameter detection unit 104, as described in FIG. 13 or FIG. 14, and outputs the return time information 126 to the notification control unit 112 (step S10α).

[0134] Then, the notification control unit 112 outputs the return time information 126 input from the time prediction unit 110 to the monitor 18 and the speaker 119 (step S10β). As a result, as shown in FIG. 15, the return time information 126 is notified (screen display and audio output) from the monitor 18 and the speaker 119.

[0135] Thereafter, the processes of steps S8 to S10, S10α, and S10β are repeatedly executed until the pupil diameter d repeatedly detected by the pupil diameter detection unit 104 becomes equal to or larger than the photographing threshold value T1. As a result, the time prediction unit 110 repeatedly updates the prediction result of the return time t, and the notification control unit 112 repeatedly notifies the return time information 126 (NO in step S10).

[0136] The process after the pupil diameter d becomes equal to or larger than the photographing threshold T1 is the same as that in the first embodiment, and therefore will not be described here. If the pupil diameter d remains smaller than the photographing threshold T1 for a certain period of time, the small pupil diameter aperture 39A may be used to photograph the fundus of the subject's eye E, as in the second embodiment.

[0137] As described above, in the fourth embodiment, when the second or subsequent fundus photographing of the subject's eye E is performed, the return time t required for the miosis of the pupil Ep of the subject's eye E to subside can be predicted and notified to the examiner, etc. This allows the examiner to recognize the return time t, i.e., the timing at which the second or subsequent fundus photographing of the subject's eye E will start.

[0138] In the fourth embodiment, the return time information 126 (return time t) is notified using the monitor 18 and the speaker 119. However, the return time information 126 may be notified using only one of the monitor 18 and the speaker 119.

[0139] [Fifth embodiment] Next, an ophthalmologic apparatus 10 according to a fifth embodiment of the present invention will be described. In each of the above-mentioned embodiments, the photographing threshold T1 is determined based on the pupil diameter d before the first fundus photographing of the subject's eye E, and the above-mentioned photographing control is executed in the second and subsequent fundus photographing based on this photographing threshold T1. In the fifth embodiment, however, the above-mentioned photographing control is executed from the first fundus photographing of the subject's eye E.

[0140] The ophthalmic apparatus 10 of the fifth embodiment has basically the same configuration as the ophthalmic apparatus 10 of each of the above-mentioned embodiments, except that the shooting threshold value T1 is stored in advance in the storage unit 92. Therefore, the same reference numerals are used to designate the same components as those of the above-mentioned embodiments in terms of function or configuration, and the description thereof will be omitted.

[0141] The imaging threshold T1 in the fifth embodiment is, for example, a threshold determined based on a standard pupil diameter d, or a threshold determined individually for various conditions such as the age and disease of the subject. The pupil diameter d of the pupil Ep of each subject may be measured in advance and stored in a hospital database or the like, so that the threshold determination unit 106 may access the database to acquire information on the pupil diameter d of the subject, and may determine the imaging threshold T1 based on the acquired information and store it in the storage unit 92.

[0142] 17 is a flowchart showing a flow of fundus photographing processing of the subject's eye E by the ophthalmologic apparatus 10 of the fifth embodiment. Note that the processing from step S1 to step S3 is the same as that of the first embodiment described with reference to FIG. 8, and therefore a detailed description thereof will be omitted.

[0143] 17, before the first (N=1) fundus photography of the subject's eye E (step S3A), the photography control unit 108 of the fifth embodiment acquires the photography threshold value T1 from the storage unit 92. Then, when the anterior-segment image acquisition unit 100 acquires the anterior-segment image D2 and the pupil diameter detection unit 104 detects the pupil diameter d (steps S4 and S5), the photography control unit 108 waits to execute the first fundus photography of the subject's eye E based on the detection result of the pupil diameter d until the pupil diameter d becomes equal to or larger than the photography threshold value T1 (NO in step S10C).

[0144] Then, when the pupil diameter d repeatedly detected by the pupil diameter detection unit 104 becomes equal to or larger than the photographing threshold T1, the photographing control unit 108 controls the fundus camera unit 14a to perform the first fundus photographing of the subject's eye E (YES in step S10C, step S11). As a result, even if the pupil Ep is constricted due to illumination light being irradiated onto the subject's eye E in another examination or the like prior to the fundus photographing, the first fundus photographing can be automatically performed by the fundus camera unit 14a as the constriction subsides. As a result, a good fundus photographed image D1 can be obtained.

[0145] As in the second embodiment, when the state in which the pupil diameter d is less than the photographing threshold T1 continues for a certain period of time or more, the fundus of the subject's eye E may be photographed using the small pupil diameter aperture 39A.

[0146] Hereinafter, when performing second or subsequent fundus photography (N≧2) of the subject's eye E, the processes from step S4 to step S11C are repeatedly executed (steps S12, S13).

[0147] As described above, in the ophthalmologic apparatus 10 of the fifth embodiment, by determining the photographing threshold value T1 in advance, the above-mentioned photographing control can be executed from the first fundus photographing of the subject's eye E. As a result, even if miosis of the pupil Ep of the subject's eye E occurs due to another examination performed before the fundus photographing, a good fundus image D1 can be obtained.

[0148] [others] In each of the above-mentioned embodiments, the pupil diameter detection unit 104 detects the pupil diameter d of the subject's eye E based on the anterior eye image D2 captured by the stereo camera 20, but the pupil diameter d may be detected based on the anterior eye image D2 captured by the fundus camera unit 14a. Even in this case, the above-mentioned photography control by the photography control unit 108 can be performed.

[0149] In each of the above embodiments, the stereo camera 20 or the fundus camera unit 14a repeatedly (continuously) captures the anterior eye image D2 from the time the photographing start operation is performed until all fundus photographing of the test eye E is completed, but photographing of the anterior eye image D2 may also be repeatedly performed for a predetermined period of time before photographing the fundus of the test eye E.

[0150] In each of the above embodiments, the diaphragm 39 and the small pupil diameter diaphragm 39A are provided separately, but a variable diaphragm whose diameter is adjustable may function as the diaphragm 39 and the small pupil diameter diaphragm 39A.

[0151] In each of the above embodiments, a combined fundus camera and optical coherence tomography device has been used as an example, but the present invention can also be applied to a fundus camera (non-mydriatic fundus camera) that photographs the fundus of a non-mydriatic test eye E. [Explanation of symbols]

[0152] 10 Ophthalmological equipment 11. Base 12 Face support 12a Chin rest 12b Forehead protector 13 Mounting stand 14 Measuring Head 14a Fundus camera unit 14b OCT unit 15 External Fixation Light 16 Control section 16a Operating lever 17 Electric drive mechanism 18 Monitors 19 Lens housing 20 Stereo Camera 20a 1st Camera 20b Second Camera 22 Calculation and control unit 30 Illumination optical system 31 Observation light source 32 Reflective Mirror 33 Condenser Lens 34 Visible light cut filter 35 Light source 36 Mirror 37 Relay Lens 38 Relay Lens 39 Aperture 39A Small pupil aperture 39B Aperture switching mechanism 40 Relay Lens 41 Perforated Mirror 42 Dichroic Mirror 43 Objective Lens 50 Imaging optical system 51 Focusing Lens 52 Mirror 53 Half Mirror 54 Visual target display section 55 Dichroic Mirror 56 Condenser Lens 57 Image sensor 58 Mirror 59 Condenser Lens 60 Image sensor 70 Focus Optical System 71 LED 72 Relay Lens 73 Split indicator plate 74 Two-hole aperture 75 Mirror 76 Condenser Lens 77 Reflector rod 80 OCT optics 81 Collimator lens unit 82 Optical path length change unit 83 Galvanometer Scanner 84 Focusing Lens 85 Mirror 86 Relay Lens 90 General Control Unit 92 Memory section 94 Image forming section 96 Data Processing Section 100 Anterior segment image acquisition unit 102 Alignment control unit 104 Pupil diameter detection unit 106 Threshold determination unit 108 Shooting control section 109 Small pupil diameter determination section 110 Time Prediction Section 112 Notification control unit 119 Speaker 120 Pupil diameter information 122 Light source information 124 Subject information 126 Return time information D1 Fundus image D2 Anterior segment image E. Examined eye Ea anterior segment Eb Pupil edge Ef fundus Ep pupil Er iris MV Actual value OA optical axis PV forecast value T1 imaging threshold T2 decision threshold W waveform d Pupil diameter t Return time

Claims

1. a camera body for photographing a fundus of a subject's eye, the camera body performing a first photographing of the fundus and a second photographing subsequent to the first photographing; an anterior segment image acquisition unit that repeatedly acquires an anterior segment image of the subject's eye at least before the fundus is photographed by the camera body; a pupil diameter detection unit that repeatedly detects a pupil diameter of the subject's eye based on the anterior-segment images repeatedly acquired by the anterior-segment image acquisition unit; an imaging control unit that causes the camera body to capture an image of the fundus when the pupil diameter detected by the pupil diameter detection unit is equal to or larger than a predetermined first threshold; a small pupil diameter aperture that is disposed in an optical path of an illumination optical system that illuminates the fundus with imaging illumination light in a visible wavelength range when imaging the fundus, the small pupil diameter aperture corresponding to an eye with a small pupil diameter; a first special photography control unit that, when the pupil diameter is smaller than the first threshold even after a predetermined period of time has elapsed based on the pupil diameter repeatedly detected by the pupil diameter detection unit after the first photography and before the start of the second photography, causes the camera body to execute the second photography with the small pupil diameter aperture disposed in the optical path; A fundus camera comprising:

2. the camera body has the illumination optical system, The fundus camera of claim 1, wherein the photographing control unit waits to perform the second photographing by the camera body until the pupil diameter becomes equal to or greater than the first threshold within the certain period of time based on the detection result of the pupil diameter repeatedly detected by the pupil diameter detection unit after the first photographing and before the start of the second photographing, and causes the camera body to perform the second photographing when the pupil diameter becomes equal to or greater than the first threshold.

3. a threshold value determining unit that determines the first threshold value based on the pupil diameter detected by the pupil diameter detecting unit before the first photographing; The fundus camera according to claim 2 , wherein the photographing control unit causes the camera body to perform the second photographing when the pupil diameter detected by the pupil diameter detection unit is equal to or greater than the first threshold determined by the threshold determination unit.

4. The fundus camera according to claim 3 , wherein the camera body performs the first photographing and the second photographing of the same subject's eye.

5. 4. The fundus camera according to claim 3, wherein, when the subject eyes are left and right eyes, the camera body performs the first photographing of one of the left and right eyes and the second photographing of the other of the left and right eyes.

6. a time prediction unit that predicts a return time until the pupil diameter expands to the first threshold value based on a detection result of the pupil diameter detection unit when the camera body executes the first photographing; a notification unit that notifies the return time predicted by the time prediction unit; The fundus camera according to claim 1 , further comprising:

7. The fundus camera according to claim 6 , wherein the time prediction section predicts the return time based on a detection result from the pupil diameter detection section and a type of the photographing illumination light.

8. The fundus camera described in claim 6, wherein the time prediction unit detects a change in the pupil diameter since the first photograph is taken based on the pupil diameter repeatedly detected by the pupil diameter detection unit, and calculates the return time based on the detection result of the change in the pupil diameter.

9. the camera body has the illumination optical system, a small pupil diameter determination unit that determines whether the subject's eye has a small pupil diameter based on a detection result of the pupil diameter detection unit; a small pupil diameter diaphragm that is disposed in an optical path of the illumination optical system and corresponds to the small pupil diameter eye; a second special photography control unit that, when the small pupil diameter determination unit determines that the subject's eye is the small pupil diameter eye, causes the camera body to photograph the fundus with the small pupil diameter aperture disposed in the optical path; The fundus camera according to claim 1 , further comprising:

10. The fundus camera of claim 9, wherein the small pupil diameter determination unit determines whether the test eye is a small pupil diameter eye based on whether the pupil diameter detected by the pupil diameter detection unit is less than a predetermined second threshold value that is smaller than the first threshold value.

11. A method for controlling a fundus camera that photographs a fundus of a subject's eye, comprising: an anterior segment image acquiring step of repeatedly acquiring an anterior segment image of the subject's eye at least before photographing the fundus; a pupil diameter detecting step of repeatedly detecting a pupil diameter of the subject's eye based on the anterior-segment images repeatedly acquired in the anterior-segment image acquiring step; an imaging control step of performing imaging of the fundus when the pupil diameter detected in the pupil diameter detection step is equal to or larger than a predetermined first threshold; a first special photography control step of performing the second photography with a small pupil diameter aperture disposed in an optical path of an illumination optical system that illuminates the fundus with photography illumination light in a visible wavelength range, when the pupil diameter is less than the first threshold value even after a predetermined period of time has elapsed based on the pupil diameter repeatedly detected in the pupil diameter detection step after the first photography of the fundus and before the start of the second photography; A method for controlling a fundus camera comprising the steps of:

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