Microscope and operation method of the same

Abstract

To provide a microscope and an operation method of the same capable of easily determining whether, the eyelid of an eye to be examined is opened, in short term.SOLUTION: A microscope comprises: a reference image acquisition part (image acquisition part 120) for acquiring, as a reference image 105, a picked up image (SP image DR, DL) of the eye to be examined E whose eyelid is opened, at a scanning start position; a comparison image acquisition part (image acquisition part 120) for acquiring as a comparison image 106, a picked up image from an imaging system at the scanning start position, before start of movement of an illumination system 20 and imaging systems 30R, 30L by a movement mechanism 14; a difference calculation part 122 for calculating difference between luminance values of pixels for pixels in the same coordinate in the comparison image and the reference image; an integration value calculation part 124 for calculating a difference integration value BD obtained by integrating the differences for pixels in the same coordinate calculated by the difference calculation part; and an eyelid determination part 130 for determining whether the eyelid of the eye to be examined is opened, on the basis of the difference integration value calculated by the integration value calculation part.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a microscope that functions as a Scheimpflug camera and a method of operating the microscope.

Background Art

[0002] The slit lamp microscopes described in Patent Document 1 and Patent Document 2 have a Scheimpflug camera including an illumination system that irradiates a slit light onto an eye to be examined, and a photographing system including a lens system and an imaging device. These illumination system and photographing system are configured to satisfy the Scheimpflug condition in which a plane including an object plane (a plane in focus on an imaging plane described later) including an illumination optical axis of the illumination system, a plane including a principal plane of the lens system, and a plane including an imaging plane of the imaging device intersect on the same straight line. Thereby, it is possible to perform photographing with focus adjusted at all positions within the object plane. For example, in the slit lamp microscopes described in Patent Document 1 and 2, photographing is performed with focus adjusted on a cross-section (from the front surface of the cornea to the rear surface of the lens) of the anterior segment of the eye to be examined.

[0003] Further, in the slit lamp microscopes described in Patent Document 1 and 2, while moving the illumination system and the photographing system in a direction perpendicular to the object plane (illumination optical axis), continuous cross-section photographing of the anterior segment of the eye by the photographing system is performed to obtain a Scheimpflug Principle (SP) image, which is a cross-sectional image (tomographic image) of the anterior segment of the eye in time series. And the slit lamp microscopes described in Patent Document 1 and 2 can generate a three-dimensional image of the anterior segment of the eye based on the obtained time-series SP images.

[0004] When continuously performing cross-section photographing of the anterior segment of the eye in such slit lamp microscopes described in Patent Document 1 and 2, if a blink of the eye to be examined occurs at the start or during the process, the cross-section of the anterior segment of the eye may not be photographed in a part of the time-series SP images. For this reason, it is normal to start cross-section photographing of the anterior segment of the eye with the slit lamp microscope after confirming that the eye to be examined is in a normal eyelid-open state.

[0005] Patent Document 3 describes a method of photographing an anterior eye segment image of an eye to be examined and detecting the eyelid opening state of the eye to be examined from this anterior eye segment image using known image processing techniques. Specifically, a method of detecting the eyelid opening state of the eye to be examined using a pattern matching method, a method of detecting the eyelid opening state of the eye to be examined by specifying boundary points between the eyelid and the iris or the pupil from the change in the luminance value of the anterior eye segment image, a method of detecting the eyelid opening state of the eye to be examined based on the ratio of the horizontal width to the vertical length of the eye to be examined, a method of detecting the eyelid opening state of the eye to be examined based on the positional relationship between the eyelid (upper eyelid) and the pupil, etc. are described. Also, a method of detecting the eyelid opening state of the eye to be examined by irradiating the eye to be examined with various patterns (dots, rings, etc.) and detecting a pattern image from an observation image obtained by imaging the return light from this eye to be examined is also known.

[0006] By applying such a method for detecting the eyelid opening state of the eye to be examined to the slit lamp microscope described in Patent Documents 1 and 2, it becomes possible to start cross-sectional imaging of the anterior eye segment by the slit lamp microscope in a state where the eye to be examined is normally open.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0008] By the way, when applying the method for detecting the eyelid opening state of the eye to be examined described in Patent Document 3 to the slit lamp microscopes described in Patent Documents 1 and 2, there is a problem that complicated image processing needs to be performed on the anterior eye segment image, which is time-consuming and laborious.

[0009] The present invention has been made in view of such circumstances, and an object thereof is to provide a microscope and an operating method of the microscope capable of easily and quickly determining whether or not the eye to be examined is open.

Means for Solving the Problems

[0010] The microscope for achieving the object of the present invention has an illumination optical axis, an illumination system that irradiates illumination light to the eye to be examined along the illumination optical axis, an imaging device, and an optical system that guides the return light from the eye to be examined irradiated with the illumination light to the imaging surface of the imaging device. A photographing system that captures the return light with the imaging device to obtain a captured image, a moving mechanism that moves the illumination system and the photographing system from the scanning start position to perform scanning of the eye to be examined with the illumination light, and during the execution of the scanning, for each of a plurality of scanning positions of the illumination light with respect to the eye to be examined, a photographing control unit that executes a photographing process of obtaining a captured image by the photographing system, and in a microscope in which an object plane including the illumination optical axis, a principal plane of the optical system, and the imaging surface satisfy the Scheimpflug condition, a reference image acquisition unit that pre-acquires, as a reference image, a captured image of the open eye to be examined that the photographing system has pre-acquired at the scanning start position, and a comparison image acquisition unit that acquires, as a comparison image, a captured image from the photographing system at the scanning start position before the moving mechanism moves the illumination system and the photographing system from the scanning start position, a difference calculation unit that calculates the difference in luminance values between pixels for each pixel at the same coordinates in the comparison image acquired by the comparison image acquisition unit and the reference image acquired by the reference image acquisition unit, an integrated value calculation unit that calculates a difference integrated value obtained by integrating the differences for each pixel at the same coordinates calculated by the difference calculation unit, and an eyelid opening determination unit that determines whether or not the eye to be examined is open based on the difference integrated value calculated by the integrated value calculation unit.

[0011] According to this microscope, it is possible to execute an eyelid opening determination as to whether or not the eye to be examined is open only by calculating the difference integrated value between the comparison image and the reference image without executing complicated image processing.

[0012] In a microscope according to another aspect of the present invention, the microscope includes a plurality of imaging systems. For each imaging system, the object plane, the principal plane, and the imaging plane satisfy the Schimperf condition. A reference image acquisition unit pre-acquires a reference image for each imaging system. A comparison image acquisition unit acquires a comparison image for each imaging system. A difference calculation unit calculates the difference for each pixel at the same coordinates between the comparison image and the reference image corresponding to the comparison image for each comparison image. An integrated value calculation unit calculates a difference integrated value for each comparison image based on the calculation result of the difference calculation unit for each comparison image. An eyelid opening determination unit determines whether or not the eye to be examined has its eyelid open based on at least any one of the difference integrated values for each comparison image calculated by the integrated value calculation unit. Thereby, it is possible to perform the eyelid opening determination of the eye to be examined without performing complicated image processing.

[0013] In a microscope according to another aspect of the present invention, the microscope includes an observation system that captures an image of the eye to be examined from a direction different from the direction of the illumination optical axis and the direction of the imaging optical axis of the imaging system to obtain an observation image of the eye to be examined. The reference image acquisition unit acquires, as reference images, an imaging image of the eye to be examined with its eyelid open pre-acquired by the imaging system at the scanning start position and an observation image of the eye to be examined with its eyelid open pre-acquired by the observation system. The comparison image acquisition unit acquires, as comparison images, the imaging image acquired by the imaging system at the scanning start position and the observation image acquired by the observation system before the movement starts. The difference calculation unit calculates the difference for each pixel at the same coordinates between the comparison image and the reference image corresponding to the comparison image for each comparison image. The integrated value calculation unit calculates a difference integrated value for each comparison image based on the calculation result of the difference calculation unit for each comparison image. The eyelid opening determination unit determines whether or not the eye to be examined has its eyelid open based on the difference integrated value for each comparison image calculated by the integrated value calculation unit. Thereby, it is possible to perform the eyelid opening determination of the eye to be examined without performing complicated image processing.

[0014] In a microscope according to another aspect of the present invention, the microscope includes a plurality of imaging systems. For each imaging system, the object plane, the principal plane, and the imaging plane satisfy the Schimperf condition. The reference image acquisition unit acquires, as reference images, the captured images of the subject eye with the eyelids open that have been acquired in advance for each imaging system at the scanning start position, and the observation images of the subject eye with the eyelids open that have been acquired in advance by the observation system. The comparison image acquisition unit acquires, as comparison images, the captured images acquired for each imaging system at the scanning start position and the observation images acquired by the observation system before the start of movement. Thereby, the eyelid opening determination of the subject eye can be performed with higher accuracy.

[0015] A microscope for achieving the object of the present invention includes an illumination system having an illumination optical axis and irradiating illumination light to a subject eye along the illumination optical axis, an imaging element, and an optical system that guides the return light from the subject eye irradiated with the illumination light to the imaging plane of the imaging element. The microscope further includes an imaging system that captures the return light with the imaging element to acquire a captured image, a movement mechanism that moves the illumination system and the imaging system from a scanning start position to perform scanning of the subject eye with the illumination light, an imaging control unit that executes an imaging process of acquiring a captured image with the imaging system for each of a plurality of scanning positions of the illumination light on the subject eye while the scanning is being performed, an observation system that captures the subject eye from a direction different from the direction of the illumination optical axis and the direction of the imaging optical axis of the imaging system to acquire an observation image of the subject eye, and a reference image acquisition unit that acquires in advance, as a reference image, an observation image of the subject eye with the eyelids open. The microscope further includes a comparison image acquisition unit that acquires an observation image from the observation system as a comparison image before the movement mechanism moves the illumination system and the imaging system from the scanning start position, a difference calculation unit that calculates the difference in luminance values between pixels for each pixel at the same coordinate in the comparison image acquired by the comparison image acquisition unit and the reference image acquired by the reference image acquisition unit, an integrated value calculation unit that calculates an integrated difference value obtained by integrating the differences for each pixel at the same coordinate calculated by the difference calculation unit, and an eyelid opening determination unit that determines whether or not the subject eye has the eyelids open based on the integrated difference value calculated by the integrated value calculation unit.

[0016] According to this microscope, it is possible to perform an eyelid opening determination as to whether or not the eye to be examined has its eyelids open, simply by calculating the differential integration value between the comparison image and the reference image without performing complicated image processing.

[0017] In a microscope according to another aspect of the present invention, until the eyelid opening determination unit determines that the eye to be examined has its eyelids open, the comparison image acquisition unit, the differential calculation unit, the integration value calculation unit, and the eyelid opening determination unit are repeatedly operated, and when the eyelid opening determination unit determines that the eye to be examined has its eyelids open, an automatic start control unit is provided that starts the scanning by the movement mechanism and the imaging process by the imaging control unit. Thereby, it is possible to automatically start the scanning by the movement mechanism and the imaging process by the imaging control unit.

[0018] In a microscope according to another aspect of the present invention, an imaging start operation for starting the scanning and the imaging process, an operation unit that receives an input of the imaging start operation that is executed in a state where the illumination system and the imaging system are at the scanning start position and the eye to be examined has its eyelids open, and when the imaging start operation is input to the operation unit, a manual start control unit that controls the movement mechanism and the imaging system to start the scanning by the movement mechanism and the imaging process by the imaging control unit, and a blink eyelid opening determination unit that determines the presence or absence of blinking of the eye to be examined during the imaging process based on the captured images acquired for each scanning position by the imaging system in the imaging process. When the blink eyelid opening determination unit determines that the eye to be examined is blinking, a re-imaging preparation unit that stops the scanning by the movement mechanism and the imaging process by the imaging control unit, drives the movement mechanism to move the illumination system and the imaging system to the scanning start position, and sets it to the imaging standby state is provided. The reference image acquisition unit executes the acquisition of the reference image when the imaging start operation is input to the operation unit, and in the imaging standby state, the comparison image acquisition unit, the differential calculation unit, the integration value calculation unit, the eyelid opening determination unit, and the automatic start control unit operate. Thereby, it is possible to acquire the reference image in the first imaging process and perform the eyelid opening determination of the eye to be examined in the imaging standby state of the subsequent imaging processes.

[0019] In the microscope according to another aspect of the present invention, the difference calculation unit calculates the difference for each pixel at the same coordinates that satisfies a predetermined pixel condition, and the pixel condition includes that neither of the pixels at the same coordinates is saturated. Thereby, pixels saturated due to the influence of the illumination light can be excluded from the target of the difference calculation.

[0020] In the microscope according to another aspect of the present invention, the illumination system irradiates the eye to be examined with slit light as illumination light.

[0021] In the microscope according to another aspect of the present invention, the moving mechanism moves the illumination system and the imaging system in a scanning direction perpendicular to the object plane.

[0022] A method of operating a microscope for achieving the object of the present invention includes an illumination system having an illumination optical axis and irradiating illumination light along the illumination optical axis to an eye to be examined, an imaging device, and an optical system that guides the return light from the eye to be examined irradiated with the illumination light to the imaging surface of the imaging device. A photographing system that acquires a photographed image by imaging the return light with the imaging device, a moving mechanism that moves the illumination system and the photographing system from the scanning start position to perform scanning of the eye to be examined with the illumination light, and during the scanning is being executed, for each of a plurality of scanning positions of the illumination light with respect to the eye to be examined, a photographing control unit that executes a photographing process of acquiring a photographed image by the photographing system. In the method of operating a microscope in which the object plane including the illumination optical axis, the principal plane of the optical system, and the imaging surface satisfy the Scheimpflug condition, a reference image acquisition step of acquiring in advance, as a reference image, a photographed image of the open eye of the eye to be examined acquired in advance by the photographing system at the scanning start position, a comparison image acquisition step of acquiring, as a comparison image, a photographed image from the photographing system at the scanning start position before the moving mechanism moves the illumination system and the photographing system from the scanning start position, a difference calculation step of calculating the difference in luminance values between pixels for each pixel at the same coordinates in the comparison image acquired in the comparison image acquisition step and the reference image acquired in the reference image acquisition step, an integrated value calculation step of calculating a difference integrated value obtained by integrating the differences for each pixel at the same coordinates calculated in the difference calculation step, and an open eye determination step of determining whether or not the eye to be examined is open based on the difference integrated value calculated in the integrated value calculation step.

[0023] In the method of operating a microscope according to another aspect of the present invention, until it is determined in the eyelid opening determination step that the eye to be examined has the eyelids open, the comparison image acquisition step, the difference calculation step, the integrated value calculation step, and the eyelid opening determination step are repeatedly executed. When it is determined in the eyelid opening determination step that the eye to be examined has the eyelids open, an automatic start control step is provided to start the scanning by the moving mechanism and the imaging process by the imaging control unit.

Advantages of the Invention

[0024] The present invention can easily and quickly determine whether the eye to be examined has the eyelids open.

Brief Description of the Drawings

[0025]

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Embodiments for Carrying Out the Invention

[0026] [Overall Configuration of the Slit Lamp Microscope] FIG. 1 is a side view of the slit lamp microscope 10 as viewed from the X - direction side. FIG. 2 is a top view of the slit lamp microscope 10 as viewed from the Y - direction side. Among the mutually orthogonal XYZ directions in the figure, the Z - direction is the front - rear direction (also referred to as the working distance direction) parallel to the forward direction approaching the eye to be examined E and the rearward direction moving away from the subject, the X - direction is the left - right direction based on the subject, and the Y - direction is the direction perpendicular to both the X - and Z - directions (here, the up - down direction).

[0027] As shown in FIGS. 1 and 2, the slit lamp microscope 10 corresponds to the microscope of the present invention and performs cross - sectional imaging of the anterior eye segment Ea of the eye to be examined E. This slit lamp microscope 10 is roughly composed of a shine - proof optical system 12, a moving mechanism 14, an observation system 50, and a control device 100.

[0028] [Shine - Proof Optical System] The shine-proof optical system 12 is held so as to be movable in the X direction by a moving mechanism 14 described later, and performs cross-sectional imaging along the YZ plane of the anterior eye part Ea of the eye to be examined E. This shine-proof optical system 12 is composed of an illumination system 20 and imaging systems 30R and 30L. In FIG. 1, illustration of the imaging systems 30R and 30L is omitted in order to prevent complication of the drawing.

[0029] <Illumination system> The illumination system 20 has an illumination optical axis O1 parallel to the Z direction, and irradiates slit-shaped illumination light L (slit light LS) onto the anterior eye part Ea of the eye to be examined E along this illumination optical axis O1. The illumination system 20 may have the same configuration as the illumination system of a conventional slit lamp microscope, and includes, for example, an illumination light source 22, a slit forming unit 24, and an objective lens 26 arranged along the illumination optical axis O1.

[0030] As the illumination light source 22, for example, an LED (light emitting diode) is used to emit the illumination light L. Visible light is used as the illumination light L, but infrared light (near-infrared light) may also be used. The illumination light L emitted from the illumination light source 22 enters the slit forming unit 24 after passing through a lens (not shown) or the like.

[0031] Note that the illumination light source 22 may be composed of a plurality of light sources. For example, the illumination light source 22 may include a light source that outputs continuous light and an illumination light source that outputs flash light. Also, the illumination light source 22 may include an anterior eye part illumination light source and a posterior eye part illumination light source. Furthermore, the illumination light source 22 may include a plurality of light sources having mutually different output wavelengths of the illumination light L.

[0032] The slit forming unit 24 has, for example, a pair of slit blades parallel to the Y direction, and changes the width of the region through which the illumination light L passes by changing the interval (slit width) in the X direction between these slit blades. Thereby, the illumination light L that has passed through the slit forming unit 24 becomes slit light LS having the X direction as the width direction and the Y direction as the length direction at the anterior eye part position during focusing.

[0033] The length of the slit light LS in the Y direction is set to be equal to or greater than the corneal diameter on the surface of the anterior eye part Ea. Note that the slit forming unit 24 may be configured to be able to change the length of the slit light LS in the Y direction.

[0034] The objective lens 26 irradiates the anterior eye part Ea with the illumination light L that has passed through the slit forming unit 24. As a result, the anterior eye part Ea is irradiated with the slit light LS.

[0035] Note that the illumination system 20 may further include a focusing optical system (not shown) for changing the focus position of the slit light LS. Also, the illumination system 20 may include an alignment light projection optical system (see Patent Document 2 above) (not shown) that irradiates alignment light (for example, spot light) for alignment detection.

[0036] <Imaging system> The imaging systems 30R and 30L image the anterior eye part Ea irradiated with the slit light LS from two different directions. The imaging systems 30R and 30L may have the same configuration as the imaging system of a conventional slit lamp microscope. For example, the imaging system 30R includes an optical system 32R and an image sensor 34R arranged along the imaging optical axis O2R. Also, the imaging system 30L includes an optical system 32L and an image sensor 34L arranged along the imaging optical axis O2L.

[0037] The imaging optical axis O2R is parallel to the ZX plane and is inclined at an angle θR to one side in the X direction with respect to the Z direction when viewed from the Y direction side. Also, the imaging optical axis O2L is parallel to the ZX plane and is inclined at an angle θL to the other side in the X direction with respect to the Z direction when viewed from the Y direction side. The angle θR and the angle θL may be equal to each other or different from each other. And the illumination optical axis O1, the imaging optical axis O2R, and the imaging optical axis O2L intersect at one point.

[0038] Although not shown in the drawings, the optical system 32R includes, for example, an objective lens, a zoom optical system, and an imaging lens in this order from the side closer to the eye E to be examined, and guides the return light LA from the anterior eye segment Ea to the imaging device 34R. The return light LA passes through the objective lens and the zoom optical system of the optical system 32R, and is imaged on the imaging surface 36R of the imaging device 34R by the imaging lens of the optical system 32R. Note that the optical system 32R may further include a focusing optical system (not shown).

[0039] The return light LA from the anterior eye segment Ea includes the return light of the slit light LS irradiated on the anterior eye segment Ea, and may further include other light. Examples of the return light LA include reflected light, scattered light, and fluorescence. Examples of other light include light from the installation environment of the slit lamp microscope 10 (room light, sunlight, etc.). Further, when an anterior eye segment illumination system (not shown) for illuminating the entire anterior eye segment Ea is provided separately from the illumination system 20, the return light (reflected light) of the anterior eye segment illumination light from this anterior eye segment illumination system may be included in the "other light".

[0040] The imaging device 34R is a CMOS (complementary metal oxide semiconductor) type or CCD (Charge Coupled Device) type area sensor having a two-dimensional imaging surface 36R. The imaging device 34R images the return light LA imaged on the imaging surface 36R by the optical system 32R, and outputs an SP image DR, which is an imaging image of this return light LA, to the control device 100. This SP image DR is a cross-sectional image of the anterior eye segment in the YZ cross-section at the slit light irradiation position of the anterior eye segment Ea.

[0041] The optical system 32L has the same configuration as the above-described optical system 32R. Although not shown in the drawings, it includes an objective lens, a zoom optical system, and an imaging lens, etc., and may further include a focusing optical system. Thereby, the return light LA from the anterior eye segment Ea irradiated with the slit light LS passes through the objective lens and the zoom optical system of the optical system 32L, and is imaged on the imaging surface 36L of the imaging device 34L by the imaging lens of the optical system 32L.

[0042] The imaging device 34L is a CMOS type or CCD type area sensor having a two-dimensional imaging surface 36L, which captures the return light LA imaged on the imaging surface 36L by the optical system 32L, and outputs an SP image DL, which is an imaging image of this return light LA, to the control device 100. This SP image DL is a cross-sectional image of the anterior eye part in the YZ cross-section at the slit light irradiation position of the anterior eye part Ea.

[0043] <Shine-proof camera> FIG. 3 is an explanatory diagram for explaining the respective configurations and arrangement conditions of the illumination system 20 and the photographing systems 30R and 30L. As shown in FIG. 3, the illumination system 20 and the photographing system 30L function as a shine-proof camera, and the illumination system 20 and the photographing system 30R also function as a shine-proof camera.

[0044] As shown by reference numeral 3A in FIG. 3, the illumination system 20 and the photographing system 30L are configured such that an object plane SP (a plane in focus on the imaging surfaces 36R and 36L) including the illumination optical axis O1 and parallel to the YZ plane, the principal plane SL of the optical system 32L, and the imaging surface 36L satisfy the conditions (principles) of shine-proof. More specifically, a plane H1 including the object plane SP, a plane H2L including the principal plane SL, and a plane H3L including the imaging surface 36L intersect on the same straight line. Thereby, the photographing system 30L focuses on all positions within the object plane SP (for example, the range from the front surface of the cornea to the rear surface of the lens of the anterior eye part Ea) and performs cross-sectional photographing of the anterior eye part Ea, so that the SP image DL is obtained.

[0045] Similarly, as shown by reference numeral 3B in FIG. 3, the illumination system 20 and the photographing system 30R are configured such that the object plane SP, the principal plane SR of the optical system 32R, and the imaging surface 36R satisfy the conditions of shine-proof. More specifically, the plane H1, a plane H2R including the principal plane SR, and a plane H3R including the imaging surface 36R intersect on the same straight line. Thereby, the photographing system 30R also focuses on all positions within the object plane SP (the range from the front surface of the cornea to the rear surface of the lens of the anterior eye part Ea) and performs cross-sectional photographing of the anterior eye part Ea, so that the SP image DR is obtained.

[0046] The configurations of the illumination system 20 and the imaging systems 30R and 30L that satisfy such anti-glare conditions are realized by the configuration and arrangement of the elements included in the illumination system 20, the configuration and arrangement of the elements included in the imaging systems 30R and 30L, and the relative positions between the illumination system 20 and the imaging systems 30R and 30L. The parameters indicating the relative positions between the illumination system 20 and the imaging systems 30R and 30L include, for example, the aforementioned angles θR and θL. The angles θR and θL are set to, for example, 17.5 degrees, 30 degrees, or 45 degrees. Note that the angles θR and θL may be variable.

[0047] [Moving mechanism] Although not shown in the figure, the moving mechanism 14 is composed of a stage on which the anti-glare optical system 12 is mounted and an actuator such as a motor that moves this stage in the XYZ directions.

[0048] When aligning the anti-glare optical system 12 with respect to the eye to be examined E, the moving mechanism 14 performs position adjustment of the anti-glare optical system 12 in the XYZ directions under the control of a control device 100 described later, thereby executing alignment (auto-alignment) of the anti-glare optical system 12 with respect to the eye to be examined E.

[0049] Further, after the auto-alignment of the anti-glare optical system 12 is completed, the moving mechanism 14 moves the anti-glare optical system 12 in response to a photographing start operation by the examiner. In this case, the moving mechanism 14 moves the anti-glare optical system 12 in a direction perpendicular to the illumination optical axis O1 in accordance with the irradiation of the slit light LS on the anterior eye part Ea by the illumination system 20 and the photographing of the SP images DR and DL by the imaging systems 30R and 30L under the control of the control device 100.

[0050] More specifically, the moving mechanism 14 moves the Schlein-proof optical system 12 in the X direction, which is the direction perpendicular to the object plane SP. As a result, the anterior eye part Ea can be scanned (scanned) in the X direction by the slit light LS parallel to the YZ plane with the X direction as the width direction and the Y direction as the length direction. At this time, in this embodiment, the moving range of the Schlein-proof optical system 12 in the X direction by the moving mechanism 14, that is, the scanning range of the slit light LS in the X direction with respect to the anterior eye part Ea, is set to at least the range including the cornea of the anterior eye part Ea. Therefore, the entire cornea can be scanned with the slit light LS. Note that the position of the Schlein-proof optical system 12 corresponding to the start end of the scanning range of the slit light LS in the X direction is referred to as the "scanning start position", and the position of the Schlein-proof optical system 12 corresponding to the end of this scanning range is referred to as the "scanning end position".

[0051] While the moving mechanism 14 scans the slit light LS from the illumination system 20 in the X direction with respect to the anterior eye part Ea, by performing imaging (video imaging) of the return light LA by the imaging systems 30R and 30L and continuous output of the SP images DR and DL for each of a plurality of scanning positions, the SP images DR and DL of the anterior eye part Ea for each scanning position can be obtained (see Patent Document 1 and Patent Document 2 above). Hereinafter, the scanning of the slit light LS in the X direction by the moving mechanism 14 and the continuous imaging of the return light LA for each scanning position by the imaging systems 30R and 30L and the continuous output of the SP images DR and DL are simply abbreviated as "SP image photographing process".

[0052] Note that the moving mechanism 14 used for alignment and the moving mechanism 14 that moves the Schlein-proof optical system 12 in the X direction may be separate bodies.

[0053] [Observation system] Returning to FIG. 1, the observation system 50 is provided independently of the Schlein-proof optical system 12, and its position is fixed within the slit lamp microscope 10, that is, its relative position with respect to the eye to be examined E is fixed.

[0054] The observation system 50 has an observation optical axis O3 and includes an optical system 52 and an image sensor 54 arranged along the observation optical axis O3 in order from the side closer to the eye to be examined E.

[0055] The observation optical axis O3 is parallel to the illumination optical axis O1 when viewed from the Y direction and is inclined by an inclination angle θ downward (or upward) in the Y direction with respect to the illumination optical axis O1 when viewed from the X direction. This inclination angle θ is set to an appropriate angle, for example, about 8 degrees, such that the slit light LS irradiated from the illumination system 20 to the anterior eye part Ea is not cut off by the observation system 50. Thereby, a decrease in the amount of light of the slit light LS irradiated from the illumination system 20 to the anterior eye part Ea is prevented.

[0056] The optical system 52 includes an imaging lens or the like (not shown in the figure) and forms an image of the return light LB (corresponding to the second return light) from the eye to be examined E on the imaging device 54. Note that the optical system 52 may include a focusing optical system.

[0057] The return light LB from the eye to be examined E includes the anterior eye part reflected light, which is the reflected light of the anterior eye part illumination light irradiated from the above-described anterior eye part illumination system (not shown in the figure) to the anterior eye part Ea, and the reflected light from the anterior eye part Ea projected from the above-described alignment light projection optical system (not shown in the figure).

[0058] The imaging device 54 is a CMOS type or CCD type area sensor. This imaging device 54 images the return light LB imaged by the optical system 52 and outputs an anterior eye part image D, which is an observation image of the anterior eye part Ea of the eye to be examined E, to the control device 100.

[0059] [Control Device] FIG. 4 is a functional block diagram of the control device 100. As shown in FIG. 4, the control device 100 includes an arithmetic circuit composed of various processors and a memory. The various processors include a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), and programmable logic devices [such as SPLD (Simple Programmable Logic Devices), CPLD (Complex Programmable Logic Device), and FPGA (Field Programmable Gate Arrays)]. Note that the various functions of the control device 100 may be realized by one processor or by a plurality of processors of the same type or different types.

[0060] The control device 100 controls the alignment detection and alignment of the Shine Prove optical system 12 with respect to the eye E to be examined, the irradiation of the slit light LS on the anterior eye part Ea by the illumination system 20, the SP image capturing process (scanning of the slit light LS, capturing of the SP images DR and DL, etc.), the blink determination of the eye E to be examined during the SP image capturing process, and the display of each SP image DR and DL.

[0061] Further, the control device 100 controls the re - execution of the SP image capturing process when a blink of the eye E to be examined occurs during the SP image capturing process, the eyelid opening determination of the eye E to be examined in the imaging standby state (imaging Ready) before starting the re - execution of the SP image capturing process, and the automatic start of the re - execution of the SP image capturing process.

[0062] In addition to the illumination system 20 (illumination light source 22), the imaging systems 30R and 30L (image sensors 34R and 34L), the moving mechanism 14, and the observation system 50 (image sensor 54), a storage unit 101, an operation unit 102, and a display unit 104 are connected to the control device 100.

[0063] In the memory unit 101, in addition to a control program (not shown) of the control device 100, SP images DR and DL for each scanning position captured by the SP image capturing process, and a reference image 105 are stored. The reference image 105 is an image used for the eyelid opening determination of the eye to be examined E described later, and is acquired at the start of the first (initial) SP image capturing process started in response to a capturing start operation by the examiner. The reference image 105 includes the SP images DR and DL acquired by the imaging systems 30R and 30L at the scanning start position described above, and the anterior eye segment image D acquired by the observation system 50 at a fixed position.

[0064] The operation unit 102 is used for various operations of the slit lamp microscope 10, such as an adjustment operation (manual alignment operation) of the position and orientation of the shine-proof optical system 12, a start operation of the auto-alignment of the shine-proof optical system 12, a capturing start operation which is a start operation of the SP image capturing process, and a switching operation of the observation mode of the slit lamp microscope 10. The operation unit 102 includes various operation devices such as hardware keys (switches, buttons) provided on the slit lamp microscope 10, operation levers, mice, keyboards, and operation panels (including the display surface of the display unit 104).

[0065] As the display unit 104, various known display devices such as a liquid crystal display device are used. The display unit 104 displays each of the SP images DR and DL continuously captured by the imaging systems 30R and 30L, and the anterior eye segment image D of the anterior eye segment Ea captured by the observation system 50.

[0066] By reading and executing a control program (not shown) in the memory unit 101, the control device 100 functions as an alignment detection unit 110, an alignment control unit 112, a scanning control unit 114, an illumination control unit 116, a capturing control unit 118, an image acquisition unit 120, a manual start control unit 121, a difference calculation unit 122, an integrated value calculation unit 124, a blink determination unit 126, a re-capturing preparation unit 128, an eyelid opening determination unit 130, an automatic start control unit 132, and a display control unit 134.

[0067] The alignment detection unit 110 controls the detection of the alignment of the eye E to be examined in the XYZ directions with respect to the shine-proof optical system 12. For example, in response to the input of an auto-alignment start operation to the operation unit 102, the alignment detection unit 110 controls an alignment light projection optical system (not shown) to start projecting alignment light onto the eye E to be examined, and causes the observation system 50 to capture an image of the anterior eye part Ea. As a result, an anterior eye part image D of the anterior eye part Ea onto which the alignment light is projected is captured by the observation system 50, and this anterior eye part image D is output from the observation system 50 to the alignment detection unit 110.

[0068] Next, the alignment detection unit 110 performs XYZ-direction alignment detection for detecting the relative position of the eye E to be examined in the XYZ directions with respect to the shine-proof optical system 12 by a known method based on the anterior eye part image D input from the observation system 50 (see, for example, Patent Document 2 above).

[0069] The alignment control unit 112 performs XYZ-direction alignment (hereinafter simply referred to as XYZ alignment) of the shine-proof optical system 12 with respect to the eye E to be examined by driving the moving mechanism 14 to adjust the XYZ-direction position of the shine-proof optical system 12 based on the XYZ-direction alignment detection result input from the alignment detection unit 110. As a result, the shine-proof optical system 12 is position-adjusted to the scanning start position of the slit light LS with respect to the anterior eye part Ea.

[0070] The scanning control unit 114 controls the driving of the moving mechanism 14 during SP image capturing processing (during the X-direction scanning of the slit light LS with respect to the anterior eye part Ea). Under the control of a manual start control unit 121 and an automatic start control unit 132, which will be described later, the scanning control unit 114 drives the moving mechanism 14 to move the shine-proof optical system 12 in the X direction from the scanning start position to the scanning end position.

[0071] The illumination control unit 116 controls the emission of illumination light L from the illumination light source 22, that is, the irradiation of slit light LS from the illumination system 20 to the anterior eye part Ea. This illumination control unit 116 emits illumination light L from the illumination light source 22 at least until the X-axis movement of the Scheimpflug optical system 12 by the movement mechanism 14 (SP image capturing process) is completed after at least the XYZ alignment is completed. Thereby, the anterior eye part Ea is scanned in the X direction by the slit light LS.

[0072] The imaging control unit 118 controls the imaging of SP images DR and DL by the imaging systems 30R and 30L (imaging of the return light LA) and the imaging of the anterior eye part Ea by the observation system 50. This imaging control unit 118 continuously executes the imaging process (video imaging process) of the SP images DR and DL by the imaging systems 30R and 30L from the start to the completion of the SP image capturing process under the control of the manual start control unit 121 and the automatic start control unit 132 described later. Thereby, during the scanning of the anterior eye part Ea by the slit light LS, the SP images DR and DL are captured by the imaging systems 30R and 30L for each scanning position of the slit light LS in the X direction.

[0073] In this embodiment, for example, the time required for scanning the anterior eye part Ea by the slit light LS is 2 seconds, and the imaging of the SP images DR and DL by the imaging systems 30R and 30L is executed at 50 frames per second during this scanning. As a result, 100 SP images DR and 100 SP images DL are obtained at 100 scanning positions of the slit light LS.

[0074] In addition, the imaging control unit 118 causes the observation system 50 to image the anterior eye part Ea in addition to imaging the SP images DR and DL by the imaging systems 30R and 30L in response to the input of an imaging start operation to the operation unit 102.

[0075] The image acquisition unit 120 functions as an image input interface that receives inputs of various images from the imaging systems 30R and 30L and the observation system 50. Each time the imaging systems 30R and 30L capture SP images DR and DL during the SP image capture process, the image acquisition unit 120 sequentially acquires the SP images DR and DL from the imaging systems 30R and 30L, sequentially stores the SP images DR and DL in the storage unit 101, and sequentially outputs them to the difference calculation unit 122.

[0076] Also, at the start of the first (initial) SP image capture process started in response to a capture start operation by the examiner, the image acquisition unit 120 stores the SP images DR and DL acquired at the scan start position by the imaging systems 30R and 30L in the storage unit 101 as the reference image 105. Further, at the start of the first (initial) SP image capture process, the image acquisition unit 120 also stores the anterior eye segment image D acquired by the observation system 50 in the storage unit 101 as the reference image 105. In this case, the image acquisition unit 120, the imaging systems 30R and 30L, and the observation system 50 function as the reference image acquisition unit of the present invention.

[0077] When the examiner inputs a capture start operation for the SP image capture process to the operation unit 102, the manual start control unit 121 controls the scan control unit 114, the illumination control unit 116, the capture control unit 118, and the image acquisition unit 120 to execute the SP image capture process and the acquisition of the SP images DR and DL and the anterior eye segment image D for the reference image 105 by the image acquisition unit 120.

[0078] At this time, the capture start operation for the SP image capture process by the examiner is executed with the test eye E being normally opened. Therefore, both the SP images DR and DL acquired by the imaging systems 30R and 30L at the scan start position in response to the capture start operation and the anterior eye segment image D acquired by the observation system 50 in response to the capture start operation are images captured with the test eye E being normally opened. Therefore, the SP images DR and DL and the anterior eye segment image D that the image acquisition unit 120 stores in the storage unit 101 as the reference image 105 are images that are guaranteed to include an image of the normally opened test eye E.

[0079] The differential calculation unit 122, the integrated value calculation unit 124, and the blink determination unit 126 determine the presence or absence of blinking of the subject eye E during SP image capturing (while scanning the anterior eye part Ea with the slit light LS) based on the SP images DR and DL that the image acquisition unit 120 continuously acquires from the imaging systems 30R and 30L during SP image capturing processing.

[0080] FIG. 5 is an explanatory diagram for explaining the differential calculation process by the differential calculation unit 122. As shown in FIG. 5 and the aforementioned FIG. 4, each time the image acquisition unit 120 newly acquires an SP image DR at a scanning position after the second (from the second sheet onwards) from the imaging system 30R, the differential calculation unit 122 executes a differential calculation process. The differential calculation process is a process of calculating the difference in luminance values between pixels for each pixel at the same coordinates in the newly acquired SP image DR from the imaging system 30R by the image acquisition unit 120 and the SP image DR (the immediately previous image) acquired from the imaging system 30R immediately before that.

[0081] For example, taking the differential calculation process by the differential calculation unit 122 when the image acquisition unit 120 newly acquires the SP image DR at the (N + 1)-th scanning position (the (N + 1)-th sheet) from the imaging system 30R as an example, where N and n are arbitrary natural numbers. Here, let the luminance value of an arbitrary pixel in the (N + 1)-th SP image DR be ImgN+1, and the luminance value of an arbitrary pixel in the N-th SP image DR be ImgN. The differential calculation unit 122 calculates the difference in luminance values between pixels [(ImgN+1) - (ImgN)] for each pixel at the same coordinates (Xn, Yn) in the (N + 1)-th and N-th SP images DR that satisfy the pixel conditions described below.

[0082] The above-mentioned pixel conditions include at least that neither the pixel of the (N + 1)-th SP image DR that is the object of the differential calculation process nor the pixel of the N-th SP image DR is saturated. Therefore, in this embodiment, the first pixel condition and the second pixel condition are set as the pixel conditions.

[0083] The first pixel condition is that both ImgN+1 and ImgN are less than 255 when the SP image DR is an 8-bit image. Also, the second pixel condition is that the difference in luminance values [(ImgN+1)-(ImgN)] satisfies 48 or more and less than 108. Note that the individual threshold values of the first pixel condition and the second pixel condition can be changed as appropriate. Also, pixel conditions other than the first pixel condition and the second pixel condition may be set.

[0084] Also, each time the image acquisition unit 120 newly acquires the SP image DL at the scanning positions from the second onwards (from the second sheet onwards) from the imaging system 30L, the difference calculation unit 122 executes a difference calculation process similar to the difference calculation process of the above-described SP image DR. In this difference calculation process, for each pixel at the same coordinates that satisfies each of the above pixel conditions in the SP image DL newly acquired by the image acquisition unit 120 from the imaging system 30L and the SP image DL (immediately previous image) acquired from the imaging system 30L immediately before (one before), the difference in luminance values between the pixels is calculated.

[0085] FIG. 6 is an explanatory diagram for explaining the calculation process of the difference integration value AD by the integration value calculation unit 124. Note that the difference integration value AD obtained by integrating the differences for each pixel at the same coordinates of the SP images DR of the (N+1)-th and N-th sheets is referred to as "difference integration value AD(N+1)".

[0086] As shown in FIG. 6 and the aforementioned FIG. 4, each time the difference calculation unit 122 executes the difference calculation process in response to the acquisition of the SP image DR from the second sheet onwards by the image acquisition unit 120, the integration value calculation unit 124 calculates the difference integration value AD obtained by integrating the differences for each pixel at the same coordinates calculated by the difference calculation unit 122. Similarly, each time the difference calculation unit 122 executes the difference calculation process in response to the acquisition of the SP image DL from the second sheet onwards by the image acquisition unit 120, the integration value calculation unit 124 calculates the difference integration value AD obtained by integrating the differences for each pixel at the same coordinates calculated by the difference calculation unit 122. As a result, the difference integration values AD [AD(2), AD(3), AD(4),… AD(N+1),…] are calculated for each of the SP images DR and DL from the second sheet onwards by the integration value calculation unit 124.

[0087] Note that the difference calculation unit 122 and the integrated value calculation unit 124 also operate during the eyelid opening determination by the eyelid opening determination unit 130 described later.

[0088] FIG. 7 is a graph showing the change in the differential integrated value AD calculated by the integrated value calculation unit 124 for each of the SP images DR and DL when no blink of the subject eye E occurs during the shooting of the SP images DR and DL by the imaging systems 30R and 30L. FIG. 8 is a graph showing the change in the differential integrated value AD calculated by the integrated value calculation unit 124 for each of the SP images DR and DL when a blink of the subject eye E occurs during the shooting of the SP images DR and DL by the imaging systems 30R and 30L.

[0089] Note that the horizontal axis of the graphs in FIGS. 7 and 8 indicates the shooting order (scanning position of the slit light LS) of the SP image DR (or SP image DL), and the vertical axis indicates the magnitude of the differential integrated value AD (here, displayed as the differential integrated value AD / 1000). Also, in the graph of FIG. 8, "OPEN" indicates the state where the eyelid of the subject eye E is open, and "CLOSE" indicates the state where the eyelid of the subject eye E is closed.

[0090] As shown in FIG. 7, when no blink of the subject eye E occurs during the shooting of the SP images DR and DL by the imaging systems 30R and 30L (hereinafter simply abbreviated as "during SP image shooting"), the change in the differential integrated value AD calculated by the integrated value calculation unit 124 for each of the SP images DR and DL falls within a substantially constant range. On the other hand, as shown in FIG. 8, when a blink of the subject eye E occurs during SP image shooting, due to this blink, the change in the differential integrated value AD calculated by the integrated value calculation unit 124 for each of the SP images DR and DL becomes large.

[0091] As described above, when a blink of the subject eye E occurs during SP image shooting (see FIG. 8), the change in the differential integrated value AD for each of the SP images DR and DL becomes larger compared to the case where no blink of the subject eye E occurs (see FIG. 7). Therefore, based on the differential integrated value AD calculated by the integrated value calculation unit 124 for each of the SP images DR and DL during SP image shooting, it is possible to determine the presence or absence of a blink of the subject eye E during SP image shooting (during the scanning of the anterior eye part Ea by the slit light LS).

[0092] Returning to FIG. 4, the blink determination unit 126 determines the presence or absence of blinking of the eye E under examination during the SP image capturing process based on the differential integrated value AD calculated by the integrated value calculation unit 124 for each of the SP images DR and DL. This blink determination unit 126 executes the calculation of the index value 140 shown in FIG. 9 described later and the calculation with the evaluation value dParam based on the calculation result of the integrated value calculation unit 124, and then determines the presence or absence of blinking of the eye E under examination based on the calculation result of the evaluation value dParam.

[0093] FIG. 9 is an explanatory diagram for explaining the calculation of the index value 140 and the evaluation value dParam by the blink determination unit 126. Here, the calculation of the index value 140 and the evaluation value dParam at the time of acquisition of the fifth SP images DR and DL is taken as an example for explanation. Also, the evaluation value dParam corresponding to the Nth SP images DR and DL is referred to as "evaluation value dParamN".

[0094] As shown in FIG. 9 and the aforementioned FIG. 4, each time the image acquisition unit 120 acquires a new (third and subsequent) SP image DR or DL, and the differential calculation unit 122 performs differential calculation processing and the integrated value calculation unit 124 performs differential integrated value AD calculation processing, the blink determination unit 126 calculates the index value 140. The index value 140 represents the statistical quantity of all the differential integrated values AD that have been calculated before the differential integrated value AD newly calculated by the integrated value calculation unit 124.

[0095] For example, when the calculation process of the new differential integrated value AD(5) by the integrated value calculation unit 124 is executed, the blink determination unit 126 calculates the index value 140 based on the differential integrated values AD(2) to AD(4) that have been calculated before that. Specifically, when the average value of the differential integrated values AD(2) to AD(4) is "Avg" and the standard deviation of the differential integrated values AD(2) to AD(4) is "SD", the blink determination unit 126 calculates (Avg + SD) as the index value 140.

[0096] Also, when a new differential integrated value AD(N) is calculated by the integrated value calculation unit 124, the blink determination unit 126 calculates an index value 140 (= Avg + SD) based on the "Avg" and "SD" of the differential integrated values AD(2) to AD(N - 1) from the previously calculated differential integrated value AD(2). Further, when a new differential integrated value AD(N + 1) is calculated by the integrated value calculation unit 124, the blink determination unit 126 calculates an index value 140 (= Avg + SD) based on the "Avg" and "SD" of the differential integrated values AD(2) to AD(N) from the previously calculated differential integrated value AD(2).

[0097] Similarly hereinafter, every time a new differential integrated value AD is calculated by the integrated value calculation unit 124, the blink determination unit 126 calculates the index value 140 based on all the differential integrated values AD that have been previously calculated by the integrated value calculation unit 124.

[0098] In this embodiment, (Avg + SD) is taken as an example to explain the index value 140 representing the statistic of the calculated differential integrated value AD, but (Avg - SD) or Avg may be used as the index value 140.

[0099] Every time the image acquisition unit 120 acquires new SP images DR, DL, the blink determination unit 126 subtracts the index value 140 from the newly calculated differential integrated value AD by the integrated value calculation unit 124 to calculate an evaluation value dParam (also referred to as an evaluation parameter value) of the newly acquired SP images DR, DL. The evaluation value dParam is used to determine whether the eye E under examination blinks.

[0100] For example, the blink determination unit 126 calculates an evaluation value dParam5 of the fifth SP images DR, DL based on the calculation result of the differential integrated value AD(5) by the integrated value calculation unit 124 and the calculation results of the index values 140 of the differential integrated values AD(2) to AD(4). Specifically, the blink determination unit 126 calculates the absolute value of the value obtained by subtracting the index value 140 from the differential integrated value AD(5) [dParam5 = |differential integrated value AD(5) - (Avg + SD)|].

[0101] Further, the blink determination unit 126 calculates an evaluation value dParamN (= |differential integrated value AD(N) - (Avg + SD)|) of the Nth SP images DR and DL based on the calculation result of the differential integrated value AD(N) by the integrated value calculation unit 124 and the calculation result of the index value 140 of the differential integrated values AD(2) to AD(N-1). Further, the blink determination unit 126 calculates an evaluation value dParamN+1 (= |differential integrated value AD(N+1) - (Avg + SD)|) of the (N+1)th SP images DR and DL based on the calculation result of the differential integrated value AD(N+1) by the integrated value calculation unit 124 and the calculation result of the index value 140 of the differential integrated values AD(2) to AD(N).

[0102] Similarly hereinafter, every time the calculation process of the differential integrated value AD by the integrated value calculation unit 124 is executed, the blink determination unit 126 repeatedly executes the calculation process of the index value 140 and the calculation process of the evaluation value dParam of the newly acquired SP images DR and DL.

[0103] Returning to FIG. 4, the blink determination unit 126 determines the presence or absence of blinking of the eye E to be examined during the SP image shooting process based on the evaluation value dParam for each of the SP images DR and DL. Specifically, when the blink determination unit 126 calculates a new evaluation value dParam, it determines whether three consecutive evaluation values dParam including this evaluation value dParam satisfy the following two first determination conditions and second determination conditions. Hereinafter, the evaluation value dParam newly calculated by the blink determination unit 126 is referred to as the "first evaluation value dParam", the evaluation value dParam calculated immediately before the first evaluation value dParam is referred to as the "second evaluation value dParam", and the evaluation value dParam calculated immediately before the second evaluation value dParam is referred to as the "third evaluation value dParam".

[0104] Based on whether the first evaluation value dParam to the third evaluation value dParam satisfy both of the following two first determination conditions and second determination conditions, the blink determination unit 126 determines the presence or absence of blinking of the eye E to be examined at the timing when the imaging systems 30R and 30L acquire the SP images DR and DL corresponding to the second evaluation value dParam.

[0105] The first determination condition is that (the second evaluation value dParam - the first evaluation value dParam) is 20 or more, and (the third evaluation value dParam - the second evaluation value dParam) is 20 or less. Also, the second determination condition is that the second evaluation value dParam is 200 or more. Note that the thresholds for the first determination condition and the second determination condition can be changed as appropriate.

[0106] Hereinafter, after the fifth SP images DR and DL are acquired by the image acquisition unit 120, a determination process will be described by taking as an example the determination by the blink determination unit 126 of the presence or absence of a blink of the eye E to be examined at the timing when the imaging systems 30R and 30L acquire the fourth SP images DR and DL.

[0107] When the blink determination unit 126 newly calculates the evaluation value dParam5 of the fifth SP images DR and DL, the blink determination unit 126 acquires this evaluation value dParam5 (the first evaluation value dParam), the evaluation value dParam4 (the second evaluation value dParam) and the evaluation value dParam3 (the third evaluation value dParam) that have already been calculated by the blink determination unit 126. Next, the blink determination unit 126 determines whether the evaluation values dParam3 to dParam5 satisfy the following two first determination conditions and second determination conditions: · First determination condition: (the evaluation value dParam4 - the evaluation value dParam3) is 20 or more, and (the evaluation value dParam5 - the evaluation value dParam4) is 20 or less. · Second determination condition: the evaluation value dParam4 is 200 or more. both at the same time.

[0108] Then, when both the first determination condition and the second determination condition are satisfied, the blink determination unit 126 determines that there is a blink of the eye E to be examined at the time of taking the fourth SP images DR and DL. Conversely, when at least one of the first determination condition and the second determination condition is not satisfied, the blink determination unit 126 determines that there is no blink of the eye E to be examined at the time of taking the fourth SP images DR and DL.

[0109] Similarly, each time the blink determination unit 126 calculates a new first evaluation value dParam, it determines the presence or absence of a blink of the subject eye E at the acquisition timing of the SP images DR and DL corresponding to the second evaluation value dParam based on the first evaluation value dParam, the calculated second evaluation value dParam, and the third evaluation value dParam.

[0110] Note that the method for determining the presence or absence of a blink of the subject eye E during the SP image capturing process by the blink determination unit 126 is not limited to the above method, and the presence or absence of a blink of the subject eye E may be determined by analyzing the SP images DR and DL using a known image processing method. In this case, it is not necessary to operate the difference calculation unit 122 and the integrated value calculation unit 124 during the SP image capturing process.

[0111] The reshooting preparation unit 128 operates when the blink determination unit 126 determines that the subject eye E has blinked during the SP image capturing process. The reshooting preparation unit 128 controls the scanning control unit 114 (moving mechanism 14) and the imaging control unit 118 (imaging systems 30R and 30L) to abort the SP image capturing process. Further, the reshooting preparation unit 128 drives the moving mechanism 14 to move the ShineProve optical system 12 to the scanning start position, thereby switching the ShineProve optical system 12 to a shooting standby state waiting for a retry (re - execution) of the SP image capturing process.

[0112] Furthermore, when the reshooting preparation unit 128 switches the ShineProve optical system 12 to the shooting standby state, it activates the image acquisition unit 120 (imaging systems 30R and 30L and observation system 50), the difference calculation unit 122, the integrated value calculation unit 124, and the eyelid opening determination unit 130 to start an eyelid opening determination for determining whether the subject eye E is normally open. As a result, the eyelid opening determination is started before the ShineProve optical system 12 starts moving from the scanning start position.

[0113] In the imaging standby state, the image acquisition unit 120 acquires the SP images DR and DL from the imaging systems 30R and 30L at the scanning start positions, and the anterior eye segment image D from the observation system 50, and outputs these SP images DR and DL and the anterior eye segment image D to the difference calculation unit 122 as the comparison image 106 (see FIG. 10). In this case, the image acquisition unit 120, the imaging systems 30R and 30L, and the observation system 50 function as the comparison image acquisition unit of the present invention.

[0114] Note that the acquisition of the comparison image 106 (SP images DR and DL and the anterior eye segment image D) by the image acquisition unit 120 and the output to the difference calculation unit 122 are repeatedly executed until the eyelid opening determination unit 130 described later determines that the subject eye E is normally open.

[0115] FIGS. 10 and 11 are explanatory diagrams for explaining the difference calculation process by the difference calculation unit 122 and the difference integrated value calculation process by the integrated value calculation unit 124 in the imaging standby state.

[0116] As shown in FIGS. 10 and 11, when a new comparison image 106 is input from the image acquisition unit 120, the difference calculation unit 122 in the imaging standby state executes a difference calculation process between the comparison image 106 and the reference image 105 previously stored in the storage unit 101. The difference calculation process in this case is a process of calculating the difference in luminance values between pixels for each pixel at the same coordinates in the comparison image 106 and the reference image 105 in the storage unit 101 corresponding to the type of the comparison image 106 (SP images DR and DL and the anterior eye segment image D), as shown in FIG. 5 described above.

[0117] For example, let the luminance of an arbitrary pixel of the comparison image 106 (SP image DR) be "ImgR1", and the luminance of an arbitrary pixel of the reference image 105 (SP image DR) be "ImgR2". The difference calculation unit 122 calculates the difference in luminance values between pixels (ImgR1 - ImgR2) for each pixel at the same coordinates (Xn, Yn) of the comparison image 106 and the reference image 105 that satisfy the above-described first pixel condition (both ImgR1 and ImgR2 are less than 255) and the second pixel condition [the difference in luminance values (ImgR1 - ImgR2) is 48 or more and less than 108] (see FIG. 10).

[0118] Also, let the luminance of an arbitrary pixel of the comparison image 106 (SP image DL) be "ImgL1", and the luminance of an arbitrary pixel of the reference image 105 (SP image DL) be "ImgL2". The difference calculation unit 122 calculates the difference in luminance values between pixels (see FIG. 10) for each pixel at the same coordinates (Xn, Yn) of the comparison image 106 and the reference image 105 that satisfy the above-described first pixel condition (both ImgL1 and ImgL2 are less than 255) and the second pixel condition [the difference in luminance values (ImgL1 - ImgL2) is 48 or more and less than 108].

[0119] Furthermore, let the luminance of an arbitrary pixel of the comparison image 106 (front eye image D) be "ImgF1", and the luminance of an arbitrary pixel of the reference image 105 (front eye image D) be "ImgF2". The difference calculation unit 122 calculates the difference in luminance values between pixels (see FIG. 11) for each pixel at the same coordinates (Xn, Yn) of the comparison image 106 and the reference image 105 that satisfy the above-described first pixel condition (both ImgF1 and ImgF2 are less than 255) and the second pixel condition [the difference in luminance values (ImgF1 - ImgF2) is 48 or more and less than 108].

[0120] Also in the difference calculation process by the difference calculation unit 122 in the imaging standby state, by setting the first pixel condition and the second image condition, pixels saturated due to the influence of the illumination light L are excluded from the target of the difference calculation. Note that pixel conditions other than the first pixel condition and the second pixel condition may be set.

[0121] In the imaging standby state, the integration value calculation unit 124 calculates a difference integration value BD obtained by integrating the differences for each pixel at the same coordinates calculated by the difference calculation unit 122 for each type of the comparison image 106 (SP image DR, DL, and front eye image D). As a result, the difference integration value BD is calculated for each type of the comparison image 106. Then, the integration value calculation unit 124 outputs the difference integration value BD to the eyelid opening determination unit 130 for each type of the comparison image 106.

[0122] The difference calculation process by the difference calculation unit 122 in the imaging standby state and the calculation process of the difference integrated value BD by the integrated value calculation unit 124 in the imaging standby state are repeatedly executed under the control of the automatic start control unit 132 described later each time the image acquisition unit 120 acquires a new comparison image 106 (SP images DR, DL, and anterior eye image D). Therefore, these difference calculation process and the calculation process of the difference integrated value BD are repeatedly executed until the eyelid opening determination unit 130 described later determines that the subject eye E is normally open.

[0123] Returning to FIG. 4, the eyelid opening determination unit 130 determines whether the subject eye E is normally open based on the calculation result of the difference integrated value BD for each type of the comparison image 106 by the integrated value calculation unit 124.

[0124] Here, as described above, the reference image 105 (SP images DR, DL, and anterior eye image D) is an image guaranteed to include an image of the subject eye E that is normally open. In addition, since the acquisition of the comparison image 106 (SP images DR, DL, and anterior eye image D) is performed in the imaging standby state (the state where the shine-proof optical system 12 is set at the scanning start position), the imaging conditions (imaging position) of the comparison image 106 and the reference image 105 are almost the same.

[0125] Therefore, if the difference integrated value BD between the comparison image 106 and the reference image 105 is small, it can be determined that the comparison image 106 includes an image similar to the reference image 105, that is, an image of the subject eye E that is normally open. Conversely, if the difference integrated value BD between the comparison image 106 and the reference image 105 is large, it can be determined that the comparison image 106 includes an image different from the reference image 105, for example, an image in which a blink of the subject eye E has occurred (the eyelid is closed). Therefore, the eyelid opening determination unit 130 determines whether the subject eye E is normally open based on the magnitude of the difference integrated value BD for each type of the comparison image 106.

[0126] Specifically, the eyelid opening determination unit 130 first calculates a parameter value ParamR, which is the value obtained by dividing the differential integration value BD corresponding to the comparison image 106 (SP image DR) by 1000, and a parameter value ParamL, which is the value obtained by dividing the differential integration value BD corresponding to the comparison image 106 (SP image DL) by 1000. Further, the eyelid opening determination unit 130 calculates a parameter value ParamF, which is the value obtained by dividing the differential integration value BD corresponding to the comparison image 106 (anterior eye image D) by 1000. Here, the parameter value ParamR, the parameter value ParamL, and the parameter value ParamF may be the differential integration value BD, or may be a value obtained by dividing the parameter value ParamF by a number other than 1000.

[0127] Next, the eyelid opening determination unit 130 determines that the eye E under test is normally opened if all the parameter values ParamR, ParamL, and ParamF are less than a predetermined threshold value, for example, less than 50. Conversely, the eyelid opening determination unit 130 determines that the eye E under test is not normally opened if at least one of the parameter values ParamR, ParamL, and ParamF is greater than or equal to the predetermined threshold value (50).

[0128] Note that the eyelid opening determination unit 130 may determine whether the eye E under test is normally opened based on whether at least one of the parameter values ParamR, ParamL, and ParamF is less than the threshold value. However, as described above, performing the eyelid opening determination using all the parameter values ParamR, ParamL, and ParamF can improve the determination accuracy more.

[0129] The eyelid opening determination process by the eyelid opening determination unit 130 is repeatedly executed under the control of the automatic start control unit 132 described later every time a new differential integrated value BD is calculated by the integrated value calculation unit 124, that is, every time the image acquisition unit 120 acquires a new comparison image 106 (SP images DR, DL, and anterior eye segment image D). Therefore, the eyelid opening determination process by the eyelid opening determination unit 130 is repeatedly executed until the eyelid opening determination unit 130 determines that the subject eye E is normally open.

[0130] The automatic start control unit 132 repeatedly executes the acquisition of the comparison image 106 by the image acquisition unit 120, the differential calculation process by the differential calculation unit 122, the calculation process of the differential integrated value BD by the integrated value calculation unit 124, and the eyelid opening determination process by the eyelid opening determination unit 130 until the eyelid opening determination unit 130 determines that the subject eye E is normally open. Thereby, when the subject eye E is normally open, this can be detected immediately.

[0131] In addition, when the eyelid opening determination unit 130 determines that the subject eye E is normally open, the automatic start control unit 132 controls the scanning control unit 114, the imaging control unit 118, etc. to automatically start redoing the SP image imaging process. Thereby, the redoing of the SP image imaging process can be automatically started.

[0132] The display control unit 134 controls the display of the display unit 104. When the SP image imaging process (including redoing) is completed, that is, when the imaging of the 100th SP images DR, DL is completed, the display control unit 134 causes the display unit 104 to display all (here, 100) SP images DR, DL acquired by the image acquisition unit 120 in the SP image imaging process in a predetermined display format. In addition, the display control unit 134 can also generate a three-dimensional image of the anterior eye segment Ea based on all the SP images DR, DL acquired by the image acquisition unit 120 in the SP image imaging process and display it on the display unit 104.

[0133] [Function of the slit lamp microscope] FIG. 12 is a flowchart showing the flow of SP image capturing processing of the anterior eye part Ea by the slit lamp microscope 10 having the above-described configuration according to the operation method of the microscope of the present invention. FIG. 13 is a flowchart showing the flow of the process (eyelid opening determination process) in step S12 in FIG. 12.

[0134] As shown in FIG. 12, when the examiner performs an auto-alignment start operation on the operation unit 102, the alignment detection unit 110 causes the alignment light projection optical system (not shown) to project alignment light onto the eye to be examined E and causes the observation system 50 to capture an image of the anterior eye part Ea. Next, the alignment detection unit 110 performs alignment detection in the XYZ directions by a known method based on the anterior eye part image D output from the observation system 50 (step S1).

[0135] Then, based on the alignment detection results in the XYZ directions by the alignment detection unit 110, the alignment control unit 112 drives the moving mechanism 14 to perform auto-alignment of the Schiempfruh optical system 12 in the XYZ directions with respect to the eye to be examined E (step S2). Note that manual alignment may be performed instead of performing auto-alignment. Thereby, the Schiempfruh optical system 12 is position-adjusted to the scanning start position of the slit light LS with respect to the anterior eye part Ea, and becomes a state waiting for an instruction to start the SP image capturing processing.

[0136] After the auto-alignment is completed, the examiner checks whether or not the eye to be examined E is normally opened, and when the eye to be examined E is normally opened, inputs a capturing start operation of the SP image capturing processing to the operation unit 102 (step S3). In response to this capturing start operation, the manual start control unit 121 controls the scanning control unit 114, the illumination control unit 116, the capturing control unit 118, and the image acquisition unit 120 to start the SP image capturing processing, the acquisition of the SP images DR and DL by the image acquisition unit 120, and the storage thereof in the storage unit 101 (step S4).

[0137] At the same time, in response to the shooting start operation, the image acquisition unit 120 causes the storage unit 101 to store, as a reference image 105, the SP images DR and DL acquired by the imaging systems 30R and 30L at the scanning start position at the start of the SP image shooting process and the anterior eye image D acquired by the observation system 50 in a distinguishable manner (step S5, corresponding to the reference image acquisition step of the present invention). By acquiring the reference image 105 in response to the shooting start operation, a reference image 105 including an image of the subject eye E with the eyelids normally opened can be surely obtained.

[0138] When the SP image shooting process is started, the image acquisition unit 120 starts acquiring the SP images DR and DL continuously output from the imaging systems 30R and 30L (step S6, NO in step S7). Then, when the image acquisition unit 120 acquires the second and subsequent SP images DR and DL, the difference calculation unit 122, the integrated value calculation unit 124, and the blink determination unit 126 operate, and a blink determination process for determining the presence or absence of a blink of the subject eye E is started (YES in step S7, step S8).

[0139] Hereinafter, every time the image acquisition unit 120 newly acquires the second and subsequent SP images DR and DL from the imaging systems 30R and 30L, the difference calculation process by the difference calculation unit 122 (see FIG. 5), the calculation process of the difference integrated value AD by the integrated value calculation unit 124 (see FIG. 6), and the calculation process of the evaluation value dParam by the blink determination unit 126 (see FIG. 9) are repeatedly executed. Then, every time the blink determination unit 126 calculates the evaluation value dParam (the first evaluation value dParam to the third evaluation value Param), it determines the presence or absence of a blink of the subject eye E during the SP image shooting process (step S8).

[0140] When the blink determination unit 126 determines that there is no blink of the subject eye E (NO in step S9), the processes from step S6 to step S9 described above are repeatedly executed (NO in step S10).

[0141] On the other hand, when the blink determination unit 126 determines that the subject eye E has blinked (YES in step S9), the reshooting preparation unit 128 controls the scanning control unit 114 and the imaging control unit 118 to cancel the SP image capturing process, and drives the moving mechanism 14 to move the Schlein-proof optical system 12 to the scanning start position. As a result, the Schlein-proof optical system 12 is switched to the imaging standby state (step S11).

[0142] After the Schlein-proof optical system 12 is switched to the imaging standby state, the image acquisition unit 120, the difference calculation unit 122, the integrated value calculation unit 124, and the eyelid opening determination unit 130 operate to start the eyelid opening determination process for the subject eye E (step S12).

[0143] As shown in FIG. 13, first, the image acquisition unit 120 acquires comparison images 106 (SP images DR, DL, and anterior eye image D) from the imaging systems 30R, 30L and the observation system 50 respectively, and outputs these comparison images 106 to the difference calculation unit 122 (step S12A, corresponding to the comparison image acquisition step of the present invention).

[0144] Next, as shown in FIGS. 10 and 11 described above, the difference calculation unit 122 performs a difference calculation process between the newly input comparison image 106 from the image acquisition unit 120 and the reference image 105 previously stored in the storage unit 101 for each type of the comparison image 106 (step S12B, corresponding to the difference calculation step of the present invention). As a result, for each pixel of the same coordinates that satisfy the above-described first pixel condition and second pixel condition in the comparison image 106 and the reference image 105, the difference in luminance values between the pixels is calculated. At this time, by setting the first pixel condition and the second pixel condition, pixels saturated due to the influence of the illumination light L are excluded from the target of the difference calculation.

[0145] Then, as shown in FIGS. 10 and 11 described above, the integrated value calculation unit 124 calculates a difference integrated value BD based on the difference calculation process result by the difference calculation unit 122 for each type of the comparison image 106 (step S12C, corresponding to the integrated value calculation step of the present invention).

[0146] When the integrated value calculation unit 124 calculates the differential integrated value BD for each type of comparison image 106, the eyelid opening determination unit 130 divides these differential integrated values BD by 1000 to calculate a parameter value ParamR, a parameter value ParamL, and a parameter value ParamF, respectively (step S12D).

[0147] Next, the eyelid opening determination unit 130 executes an eyelid opening determination to determine whether the test eye E is normally opened based on whether all of the parameter values ParamR, the parameter value ParamL, and the parameter value ParamF are less than a predetermined threshold value (less than 50) (step S12E, corresponding to the eyelid opening determination step of the present invention). By performing the eyelid opening determination using all of the parameter values ParamR, the parameter value ParamL, and the parameter value ParamF, the determination accuracy of the eyelid opening determination becomes higher.

[0148] Note that, as described above, the eyelid opening determination unit 130 may execute the eyelid opening determination of the test eye E based on whether one or two selected from among the parameter value ParamR, the parameter value ParamL, and the parameter value ParamF are less than the threshold value. In this case, since it is not necessary to perform the arithmetic processing (including the differential arithmetic processing and the differential integrated value BD arithmetic processing) of all of the parameter values ParamR, the parameter value ParamL, and the parameter value ParamF, the eyelid opening determination can be executed in a shorter time.

[0149] When the eyelid opening determination unit 130 determines that the test eye E is not normally opened, the automatic start control unit 132 controls the image acquisition unit 120, the differential arithmetic unit 122, the integrated value calculation unit 124, and the eyelid opening determination unit 130 to repeatedly execute the processing from the aforementioned step S12A to step S12E (NO in step S12E, step S12F). Similarly hereinafter, until the eyelid opening determination unit 130 determines that the test eye E is normally opened (YES in step S12E), the processing from the aforementioned step S12A to step S12E is repeatedly executed.

[0150] On the other hand, when the eyelid opening determination unit 130 determines that the test eye E is normally opened (YES in step S12E, step S12G), the automatic start control unit 132 ends the eyelid opening determination process.

[0151] Then, returning to FIG. 12, the automatic start control unit 132 controls the scanning control unit 114, the imaging control unit 118, etc., to automatically start the retry of the SP image imaging process (step S4, corresponding to the automatic start control step of the present invention). As a result, the processes after step S6 are executed again. Since the retry of the SP image imaging process can be automatically started without missing the optimal imaging timing, the labor of the examiner can be reduced and the imaging time can be shortened.

[0152] Hereinafter, until the SP image imaging process is completed, that is, until the Shine-proof optical system 12 reaches the scanning end position and the imaging of the specified number of SP images DR and DL (here, 100 images) is completed, the above-described processes are repeatedly executed (NO in step S10).

[0153] When the imaging process of the specified number of SP images is completed (YES in step S10), the display control unit 134 causes the display unit 104 to display each of the SP images DR and DL acquired and stored by the image acquisition unit 120 in a predetermined display format, or causes the display unit 104 to display a three-dimensional image of the anterior eye part Ea generated based on each of the SP images DR and DL (step S13).

[0154] As described above, in the slit lamp microscope 10 of the present embodiment, by repeatedly executing the acquisition of the comparison image 106 in the imaging standby state and the calculation of the differential integration value BD (parameter value ParamR, parameter value ParamL, and parameter value ParamF) of the comparison image 106 and the reference image 105, it is possible to determine whether or not the test eye E is opened. As a result, it is possible to execute the eyelid opening determination only by calculating the differential integration value BD without performing complicated image processing on the anterior eye part image D as in the prior art. As a result, the eyelid opening determination can be executed more simply and in a shorter time than in the prior art, so that the SP image imaging process can be efficiently executed.

[0155] [Modification Example of Eyelid Opening Determination Process] FIG. 14 is a flowchart showing a modification example of the process (eyelid opening determination process) in step S12 in FIG. 13. As shown in FIG. 14, when re - executing the SP image capturing process in response to the determination (step S12G) of the eyelid opening determination unit 130 that the subject eye E is normally opened, the reference image 105 stored in the storage unit 101 may be updated. That is, when the eyelid opening determination unit 130 determines that the subject eye E is normally opened, the image acquisition unit 120 causes the storage unit 101 to store the comparison images 106 (SP images DR, DL, anterior eye segment image D) used for the determination as a new reference image 105. Thereby, in the next imaging standby state, the eyelid opening determination process is executed using the new reference image 105.

[0156] [Others] In the above - described embodiment, in the imaging standby state before re - executing the SP image capturing process, the automatic start control of the eyelid opening determination process and the SP image capturing process is executed. However, the automatic start control of the eyelid opening determination process and the SP image capturing process may also be executed at the time of the first SP image capturing process. In this case, for example, after the image acquisition unit 120 acquires the reference image 105 in response to the examiner's imaging start operation or the like after the completion of auto - alignment, the above - described automatic start control of the eyelid opening determination process and the SP image capturing process, etc. is executed.

[0157] In the above - described embodiment, after the completion of auto - alignment, the image acquisition unit 120 acquires the reference image 105 (SP images DR, DL, anterior eye segment image D) in response to the examiner's imaging start operation. However, the present invention is not limited to this. For example, when the SP image capturing process of the subject eye E is executed regularly or irregularly, it is not necessary to execute the acquisition of the reference image 105 every time, and the eyelid opening determination process may be executed using the reference image 105 acquired in the past. In this case, the image acquisition unit 120 acquires the reference image 105 captured in the past from a medical server or the like.

[0158] In the above-described embodiment, the eyelid opening determination process is executed by comparing the comparison image 106 and the reference image 105 obtained by photographing the eye E to be examined of the same subject. However, as the reference image 105, an image obtained by photographing the eye of a model (a person other than the subject) or a model eye simulating a human eye may be used in the photographing systems 30R and 30L and the observation system 50.

[0159] In the above-described embodiment, the Shine-proof optical system 12 is moved in the X direction by the moving mechanism 14 to scan the slit light LS parallel to the YZ plane in the X direction. However, the length direction and the scanning direction of the slit light LS can be arbitrarily changed. Note that the anterior eye part Ea may be scanned by the slit light LS by rotating the Shine-proof optical system 12 around the illumination optical axis O1.

[0160] In the above-described embodiment, the anterior eye part Ea is irradiated with the slit light LS. However, the irradiation position of the slit light LS in the eye E to be examined may be appropriately changed. Further, in the above-described embodiment, the eye E to be examined is irradiated with the slit light LS. However, the eye E to be examined may be irradiated with illumination light L having various shapes other than the slit light LS.

[0161] In the above-described first embodiment, two photographing systems 30R and 30L are provided in the Shine-proof optical system 12. However, the number of photographing systems may be one or three or more.

Explanation of Reference Numerals

[0162] 10… Slit lamp microscope 12… Shine-proof optical system 14… Moving mechanism 20… Illumination system 22… Illumination light source 24… Slit forming portion 26… Objective lens 30L, 30R… Photographing system 32L, 32R… Optical system 34L, 34R… Image sensor 36L, 36R… Imaging plane 50… Observation system 52… Optical system 54… Image sensor 100…Control device 101…Memory unit 102…Operation unit 104…Display unit 105…Reference image 106…Comparison image 110…Alignment detection unit 112…Alignment control unit 114…Scanning control unit 116…Illumination control unit 118…Photographing control unit 120…Image acquisition unit 121…Manual start control unit 122…Difference calculation unit 124…Integrated value calculation unit 126…Judgment unit 128…Reshooting preparation unit 130…Eyelid opening judgment unit 132…Automatic start control unit 134…Display control unit 140…Index value AD, BD…Differential integrated value D…Anterior eye segment image DL, DR…Image E…Eye to be examined Ea…Anterior eye segment H1…Plane H2L, H2R…Plane H3L, H3R…Plane L…Illumination light LA, LB…Return light LS…Slit light O1…Illumination optical axis O2L, O2R…Photographing optical axis O3…Observation optical axis SL, SR…Principal plane SP…Object plane

Claims

1. An illumination system having an illumination optical axis and irradiating illumination light to an eye to be examined along the illumination optical axis, an imaging device, and an optical system that guides return light from the eye to be examined irradiated with the illumination light to an imaging surface of the imaging device, and a photographing system that acquires an imaging image by imaging the return light with the imaging device, a moving mechanism that moves the illumination system and the photographing system from a scanning start position to perform scanning of the eye to be examined with the illumination light, a photographing control unit that executes a photographing process of acquiring the imaging image by the photographing system for each of a plurality of scanning positions of the illumination light with respect to the eye to be examined while the scanning is being executed, comprising: In a microscope in which an object plane including the illumination optical axis, a principal plane of the optical system, and the imaging surface satisfy the Schimperf condition, a reference image acquisition unit that pre-acquires, as a reference image, the imaging image of the eye to be examined with the eyelids open that has been pre-acquired by the photographing system at the scanning start position, a comparison image acquisition unit that acquires, as a comparison image, the imaging image from the photographing system at the scanning start position before the moving mechanism moves the illumination system and the photographing system from the scanning start position, a difference calculation unit that calculates a difference in luminance value between pixels for each pixel at the same coordinate in the comparison image acquired by the comparison image acquisition unit and the reference image acquired by the reference image acquisition unit, an integrated value calculation unit that calculates a difference integrated value obtained by integrating the differences for each pixel at the same coordinate calculated by the difference calculation unit, an eyelid opening determination unit that determines whether or not the eye to be examined has its eyelids open based on the difference integrated value calculated by the integrated value calculation unit, A microscope comprising:

2. Comprising a plurality of the photographing systems, wherein for each photographing system, the object plane, the principal plane, and the imaging surface satisfy the Schimperf condition, the reference image acquisition unit pre-acquires the reference image for each photographing system, the comparison image acquisition unit acquires the comparison image for each photographing system, the difference calculation unit calculates, for each comparison image, the difference between pixels at the same coordinate in the comparison image and the reference image corresponding to the comparison image, the integrated value calculation unit calculates a difference integrated value for each comparison image based on the calculation result of the difference calculation unit for each comparison image, The microscope according to claim 1, wherein the eyelid opening determination unit determines whether or not the eye to be examined has its eyelids open based on at least any one of the difference integrated values for each comparison image calculated by the integrated value calculation unit.

3. An observation system that photographs the eye to be examined from a direction different from the direction of the illumination optical axis and the direction of the imaging optical axis of the imaging system, and acquires an observation image of the eye to be examined. The reference image acquisition unit acquires, as the reference image, the captured image of the eye to be examined with the eyelids open, which has been acquired in advance by the imaging system at the scanning start position, and the observation image of the eye to be examined with the eyelids open, which has been acquired in advance by the observation system. Before the start of movement, the comparison image acquisition unit acquires, as the comparison image, the captured image acquired by the imaging system at the scanning start position and the observation image acquired by the observation system. The difference calculation unit calculates the difference for each pixel at the same coordinates between the comparison image and the reference image corresponding to the comparison image for each comparison image. Based on the calculation result of the difference calculation unit for each comparison image, the integrated value calculation unit calculates the difference integrated value for each comparison image. The microscope according to claim 1, wherein the eyelid opening determination unit determines whether or not the eye to be examined has its eyelids open based on the difference integrated value for each comparison image calculated by the integrated value calculation unit.

4. It includes a plurality of the imaging systems, and for each imaging system, the object plane, the principal plane, and the imaging plane satisfy the Schimperf condition. The reference image acquisition unit acquires, as the reference image, the captured image of the eye to be examined with the eyelids open, which has been acquired in advance for each imaging system at the scanning start position, and the observation image of the eye to be examined with the eyelids open, which has been acquired in advance by the observation system. The microscope according to claim 3, wherein before the start of movement, the comparison image acquisition unit acquires, as the comparison image, the captured image acquired for each imaging system at the scanning start position and the observation image acquired by the observation system.

5. An illumination system having an illumination optical axis and irradiating illumination light to the eye to be examined along the illumination optical axis. An imaging system having an imaging element and an optical system that guides the return light from the eye to be examined irradiated with the illumination light to the imaging plane of the imaging element, and the imaging element captures the return light to acquire a captured image. A movement mechanism that moves the illumination system and the imaging system from the scanning start position to perform scanning of the eye to be examined with the illumination light. During the execution of the scanning, an imaging control unit that executes an imaging process of acquiring the captured image by the imaging system for each of a plurality of scanning positions of the illumination light with respect to the eye to be examined. An observation system that captures an image of the eye to be examined from a direction different from the direction of the illumination optical axis and the direction of the imaging optical axis of the imaging system, and obtains an observation image of the eye to be examined. Comprising In a microscope in which an object plane including the illumination optical axis, the principal plane of the optical system, and the imaging plane satisfy the Schimperf condition A reference image acquisition unit that pre-acquires the observation image of the eye to be examined with the eyelid open as a reference image A comparison image acquisition unit that acquires the observation image from the observation system as a comparison image before the moving mechanism moves the illumination system and the imaging system from the scanning start position A difference calculation unit that calculates the difference in luminance values between pixels for each pixel at the same coordinates in the comparison image acquired by the comparison image acquisition unit and the reference image acquired by the reference image acquisition unit An integrated value calculation unit that calculates a difference integrated value obtained by integrating the differences for each pixel at the same coordinates calculated by the difference calculation unit An eyelid opening determination unit that determines whether the eye to be examined has its eyelid open based on the difference integrated value calculated by the integrated value calculation unit A microscope comprising

6. Until the eyelid opening determination unit determines that the eye to be examined has its eyelid open, the comparison image acquisition unit, the difference calculation unit, the integrated value calculation unit, and the eyelid opening determination unit are repeatedly operated. When the eyelid opening determination unit determines that the eye to be examined has its eyelid open, an automatic start control unit that starts the scanning by the moving mechanism and the imaging process by the imaging control unit is provided. The microscope according to any one of claims 1 to 5.

7. An imaging start operation for starting the scanning and the imaging process, and an operation unit that receives an input of the imaging start operation that is executed in a state where the illumination system and the imaging system are at the scanning start position and the eye to be examined has its eyelid open A manual start control unit that controls the moving mechanism and the imaging system when the imaging start operation is input to the operation unit, and starts the scanning by the moving mechanism and the imaging process by the imaging control unit A blink eyelid opening determination unit that determines the presence or absence of blinking of the eye to be examined during the imaging process based on the captured image acquired for each scanning position by the imaging system in the imaging process When the blink eyelid opening determination unit determines that the eye to be examined has blinked, a re-imaging preparation unit that aborts the scanning by the moving mechanism and the imaging process by the imaging control unit, drives the moving mechanism, and moves the illumination system and the imaging system to the scanning start position to enter an imaging standby state Comprising When the reference image acquisition unit executes acquisition of the reference image when the shooting start operation is input to the operation unit, The microscope according to claim 6, wherein in the shooting standby state, the comparison image acquisition unit, the difference calculation unit, the integrated value calculation unit, the eyelid opening determination unit, and the automatic start control unit operate.

8. The difference calculation unit calculates the difference for each pixel at the same coordinates that satisfy a predetermined pixel condition, The microscope according to any one of claims 1 to 5, wherein the pixel condition includes that neither of the pixels at the same coordinates is saturated.

9. The microscope according to any one of claims 1 to 5, wherein the illumination system irradiates the eye to be examined with slit light as the illumination light.

10. The microscope according to any one of claims 1 to 5, wherein the moving mechanism moves the illumination system and the imaging system in a scanning direction perpendicular to the object plane.

11. An illumination system having an illumination optical axis and irradiating illumination light to the eye to be examined along the illumination optical axis, An imaging device, and an optical system that guides the return light from the eye to be examined irradiated with the illumination light to the imaging surface of the imaging device, and an imaging system that acquires an imaging image by imaging the return light with the imaging device, A moving mechanism that moves the illumination system and the imaging system from a scanning start position to perform scanning of the eye to be examined with the illumination light, A shooting control unit that executes a shooting process of acquiring the imaging image by the imaging system for each of a plurality of scanning positions of the illumination light with respect to the eye to be examined while the scanning is being executed, Comprising, In a method of operating a microscope in which an object plane including the illumination optical axis, a principal plane of the optical system, and the imaging surface satisfy the Scheimpflug condition, A reference image acquisition step of acquiring in advance, as a reference image, the imaging image of the eye to be examined with the eyelids open acquired in advance by the imaging system at the scanning start position, A comparison image acquisition step of acquiring, as a comparison image, the imaging image from the imaging system at the scanning start position before the moving mechanism moves the illumination system and the imaging system from the scanning start position, A difference calculation step of calculating the difference in luminance values between pixels for each pixel at the same coordinates in the comparison image acquired in the comparison image acquisition step and the reference image acquired in the reference image acquisition step, An integrated value calculation step of calculating an integrated difference value obtained by integrating the differences for each pixel at the same coordinates calculated in the difference calculation step An eyelid opening determination step of determining whether or not the eye to be examined has its eyelid open based on the differential integrated value calculated in the integrated value calculation step; An operating method of a microscope having the same.

12. Until it is determined in the eyelid opening determination step that the eye to be examined has its eyelid open, the comparison image acquisition step, the difference calculation step, the integrated value calculation step, and the eyelid opening determination step are repeatedly executed. When it is determined in the eyelid opening determination step that the eye to be examined has its eyelid open, an automatic start control step of starting the scanning by the moving mechanism and the imaging process by the imaging control unit is provided. The operating method of the microscope according to claim 11.

Images