Ophthalmologic apparatus, method for controlling ophthalmologic apparatus, program, and recording medium

Abstract

To provide a novel alignment method applicable to an ophthalmologic apparatus that performs anterior eye part scanning using slit light.SOLUTION: An ophthalmologic apparatus 1 performs coarse alignment by generating a frontal image of an anterior eye part using a first illumination system 2A and a first imaging system 3A and then performs fine alignment by generating a pair of Scheimpflug images of the anterior eye part using a second illumination system 2B and second imaging systems 3BL and 3BR. After fine alignment, the ophthalmologic apparatus 1 scans the anterior eye part using slit light through the second illumination system 2B and the second imaging systems 3BL and 3BR. The coarse alignment is performed to render Purkinje images caused by corneal reflection of light from the second illumination system 2B on the Scheimpflug images generated by the second imaging systems 3BL and 3BR. The fine alignment is performed using the Purkinje images rendered in the Scheimpflug images.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to an ophthalmic device, a method for controlling the ophthalmic device, a program, and a recording medium.

Background Art

[0002] In the field of ophthalmology, image diagnosis plays an important role. In ophthalmic image diagnosis, various types of ophthalmic devices (ophthalmic imaging devices) such as a slit lamp microscope, a fundus camera, a scanning laser ophthalmoscope (SLO), and an optical coherence tomography (OCT) are used. The ophthalmic devices having an imaging function are not limited to these ophthalmic imaging devices, and imaging functions are also incorporated in ophthalmic examination devices and ophthalmic measurement devices such as a refractometer, a keratometer, a tonometer, a specular microscope, a wavefront analyzer, and a microperimeter.

[0003] Many ophthalmic devices perform alignment of the device (optical system) with respect to the eye to be examined as a preparatory operation for imaging or examination. This alignment is called alignment. There are various alignment methods. For example, Patent Document 1 describes various conventional alignment methods such as a method using an alignment index, a method using a stereo camera, a method using a Purkinje image, and a method using a light lever.

[0004] In addition, Patent Document 2 describes an ophthalmic device (anterior eye segment imaging device, anterior eye segment scanner) configured to scan the anterior eye segment by moving a shine-proof optical system formed by an illumination system that projects slit light onto the anterior eye segment from a predetermined direction and an imaging system that images the anterior eye segment from another direction.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] One object of the present disclosure is to provide a novel alignment method applicable to an ophthalmic device that performs anterior eye segment scanning using slit light.

Means for Solving the Problems

[0007] One exemplary aspect of the embodiment is an ophthalmic device, including: an illumination unit including a first illumination system that projects first illumination light onto the anterior eye part of the eye to be examined and a second illumination system that projects second illumination light onto the anterior eye part from the front; an imaging unit including a first imaging system that images the anterior eye part from the front and a pair of second imaging systems that image the anterior eye part obliquely and from different directions; a moving mechanism that moves the illumination unit and the imaging unit; and a processor. Each of the second illumination system and the pair of second imaging systems is configured as a shine-proof optical system that satisfies shine-proof conditions. The processor executes a first alignment process including: a process of analyzing a first anterior eye part image obtained by imaging the anterior eye part onto which the first illumination light has been projected with the first imaging system to obtain a first relative position of the illumination unit and the imaging unit with respect to the eye to be examined; and a process of controlling the moving mechanism based on the first relative position. After the first alignment process, the processor executes a second alignment process including: a process of analyzing a pair of second anterior eye part images obtained by imaging the anterior eye part onto which the second illumination light has been projected with the pair of second imaging systems to obtain a second relative position of the illumination unit and the imaging unit with respect to the eye to be examined; and a process of controlling the moving mechanism based on the second relative position. After the second alignment, the processor executes an imaging process combining: a process of controlling the second illumination system to project slit light onto the anterior eye part from the front; a process of controlling the pair of second imaging systems to generate a time-series image of the anterior eye part onto which the slit light has been projected; and a process of controlling the moving mechanism to move the illumination unit and the imaging unit in the width direction of the slit light.

[0008] Another exemplary aspect of the embodiment is an ophthalmic device, comprising: an illumination unit including a first illumination system that projects first illumination light onto the anterior eye part of the eye to be examined, and a second illumination system that projects second illumination light onto the anterior eye part from the front; an imaging unit including a first imaging system that images the anterior eye part from the front, and a second imaging system that images the anterior eye part obliquely; a moving mechanism that moves the illumination unit and the imaging unit; and a processor. The second illumination system and the second imaging system are configured as a shine-proof optical system that satisfies shine-proof conditions. The processor executes a first alignment process including a process of analyzing an anterior eye part image obtained by imaging the anterior eye part onto which the first illumination light has been projected with the first imaging system to obtain a first relative position of the illumination unit and the imaging unit with respect to the eye to be examined, and a process of controlling the moving mechanism based on the first relative position. After the first alignment process, the processor executes a second alignment process including a process of analyzing a pair of anterior eye part images obtained by imaging the anterior eye part onto which the second illumination light has been projected with the first imaging system and the second imaging system to obtain a second relative position of the illumination unit and the imaging unit with respect to the eye to be examined, and a process of controlling the moving mechanism based on the second relative position. After the second alignment, the processor executes an imaging process combining a process of controlling the second illumination system to project slit light onto the anterior eye part from the front, a process of controlling the second imaging system to generate a time-series image of the anterior eye part onto which the slit light has been projected, and a process of controlling the moving mechanism to move the illumination unit and the imaging unit in the width direction of the slit light.

[0009] Still another exemplary aspect of the embodiment is a method of controlling an ophthalmic device for photographing the anterior segment of an eye to be examined. The ophthalmic device includes an illumination unit including a first illumination system that projects first illumination light onto the anterior segment of the eye to be examined and a second illumination system that projects second illumination light onto the anterior segment from the front, a photographing unit including a first photographing system that photographs the anterior segment from the front and a pair of second photographing systems that photograph the anterior segment obliquely and from different directions, a moving mechanism that moves the illumination unit and the photographing unit, and a processor. Each of the second illumination system and the pair of second photographing systems is configured as a shine-proof optical system that satisfies the shine-proof condition. The first illumination system is controlled to project the first illumination light onto the anterior segment, and the first photographing system is controlled to acquire a first anterior segment image. The processor is caused to execute a first alignment process including a process of analyzing the first anterior segment image to obtain a first relative position of the illumination unit and the photographing unit with respect to the eye to be examined and a process of controlling the moving mechanism based on the first relative position. After the first alignment process, the second illumination system is controlled to project the second illumination light onto the anterior segment, and the pair of second photographing systems is controlled to acquire a pair of second anterior segment images. The processor is caused to execute a second alignment process including a process of analyzing the pair of second anterior segment images to obtain a second relative position of the illumination unit and the photographing unit with respect to the eye to be examined and a process of controlling the moving mechanism based on the second relative position. After the second alignment, the processor is caused to execute a photographing process combining a process of controlling the second illumination system to project slit light onto the anterior segment from the front, a process of controlling the pair of second photographing systems to generate a time-series image of the anterior segment onto which the slit light is projected, and a process of controlling the moving mechanism to move the illumination unit and the photographing unit in the width direction of the slit light.

[0010] Yet another exemplary aspect of the embodiment is a method of controlling an ophthalmic device for photographing the anterior segment of an eye to be examined, the ophthalmic device including an illumination unit including a first illumination system that projects first illumination light onto the anterior segment of the eye to be examined and a second illumination system that projects second illumination light onto the anterior segment from the front, a photographing unit including a first photographing system that photographs the anterior segment from the front and a second photographing system that photographs the anterior segment obliquely, a moving mechanism that moves the illumination unit and the photographing unit, and a processor, wherein the second illumination system and the second photographing system are configured as a shine-proof optical system that satisfies shine-proof conditions, controlling the first illumination system to project the first illumination light onto the anterior segment and controlling the first photographing system to acquire an anterior segment image, causing the processor to execute a first alignment process including a process of analyzing the anterior segment image to obtain a first relative position of the illumination unit and the photographing unit with respect to the eye to be examined and a process of controlling the moving mechanism based on the first relative position, after the first alignment process, controlling the second illumination system to project the second illumination light onto the anterior segment and controlling the first photographing system and the second photographing system to acquire a pair of anterior segment images, causing the processor to execute a second alignment process including a process of analyzing the pair of anterior segment images to obtain a second relative position of the illumination unit and the photographing unit with respect to the eye to be examined and a process of controlling the moving mechanism based on the second relative position, after the second alignment, causing the processor to execute a photographing process combining a process of controlling the second illumination system to project slit light onto the anterior segment from the front, a process of controlling the second photographing system to generate a time-series image of the anterior segment onto which the slit light is projected, and a process of controlling the moving mechanism to move the illumination unit and the photographing unit in the width direction of the slit light.

[0011] Yet another exemplary aspect of the embodiment is a program for causing a computer to execute the method according to any of the exemplary aspects.

[0012] Yet another exemplary aspect of the embodiment is a computer-readable non-transitory recording medium on which the program according to any of the exemplary aspects is recorded.

Advantages of the Invention

[0013] According to the embodiment, it is possible to provide a novel alignment method applicable to an ophthalmic apparatus that performs anterior eye segment scanning using slit light.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

[0015] Non-limiting embodiments according to the present disclosure will be described.

[0016] Any known technology can be combined with the embodiments. For example, any matter described in the documents cited in the present disclosure can be combined with any aspect of the embodiments. Further, at least one of any known document in the technical field of the present disclosure, any known technology in a technical field similar to the technical field of the present disclosure, and any known technology in a technical field different from the technical field of the present disclosure can be combined with any aspect of the embodiments.

[0017] For example, the matters disclosed in Patent Document 2 (Japanese Patent Application Laid-Open No. 2023-49320) can be incorporated into the present disclosure by reference. More generally, any technical matters (matters disclosed in patent applications, papers, etc.) disclosed by the applicant of the present application regarding the technology related to the present disclosure can be incorporated into the present disclosure by reference.

[0018] Any two or more of the various non-limiting aspects according to the embodiments can be at least partially combined.

[0019] At least a part of the functions of any of the aspects described in this disclosure is implemented using circuitry or processing circuitry. The circuitry or processing circuitry includes a general-purpose processor, a dedicated processor, an integrated circuit, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), a programmable logic device (e.g., any of a SPLD (Simple Programmable Logic Device), a CPLD (Complex Programmable Logic Device), an FPGA (Field Programmable Gate Array), a conventional circuitry, and any combination thereof) configured and / or programmed to execute at least a part of the disclosed functions. A processor is regarded as a processing circuitry or circuitry including transistors and / or other circuitry. In this disclosure, terms such as circuitry, unit, means, or the like refer to hardware that executes at least a part of the disclosed functions, or hardware programmed to execute at least a part of the disclosed functions. The hardware may be the hardware disclosed in this specification, or may be known hardware programmed and / or configured to execute at least a part of the described functions. When the hardware is a processor that can be regarded as a certain type of circuitry, the terms such as circuitry, unit, means, or the like refer to a combination of hardware and software, and this software is used to configure the hardware and / or the processor.

[0020] <Summary of Embodiments> Many ophthalmic devices can image the anterior eye with an optical system having a relatively wide angle of view while illuminating a wide range of the anterior eye, and perform preparatory operations such as alignment while referring to the obtained wide-angle image.

[0021] On the other hand, an ophthalmic device that functions as an anterior eye segment scanner for scanning the anterior eye segment using slit light is configured to project slit light onto the anterior eye segment from a predetermined direction and photograph the anterior eye segment from a direction inclined with respect to the slit light projection direction. The image obtained thereby depicts a cross-section of the anterior eye segment corresponding to the region where the slit light is projected. Therefore, such an ophthalmic device (anterior eye segment scanner) has a very narrow angle of view compared to many ophthalmic devices and it is difficult to perform preparatory operations. In particular, in alignment, it is necessary to align the optical axis of the optical system with characteristic points of the anterior eye segment (for example, the corneal apex, the pupil center) or adjust the distance between the eye under examination and the optical system, but it is difficult to precisely perform those operations while referring to the cross-sectional image.

[0022] One object of an embodiment according to the present disclosure is to provide a new method for causing an ophthalmic device that performs anterior eye segment scanning with slit light to execute high-quality alignment. Note that the effects of the embodiments according to the present disclosure are not limited to the effects achieved by the accomplishment of this object. In the present disclosure, several non-limiting aspects of the embodiments will be described, but those skilled in the art will be able to understand that each of these aspects exhibits effects corresponding to its features (configuration, operation, action, use, etc.).

[0023] A first aspect of the embodiment is an ophthalmic device including an illumination unit, a photographing unit, a moving mechanism, and a processor.

[0024] The illumination unit is configured to project illumination light onto the eye under examination. The illumination unit includes a first illumination system and a second illumination system. The first illumination system and the second illumination system may be separate elements or the same element. Also, a part of the first illumination system and a part of the second illumination system may be configured by a common element.

[0025] The imaging unit is configured to image the eye to be examined. The imaging unit includes a first imaging system and a pair of second imaging systems. The number of second imaging systems included in the imaging unit is not limited to two, and may be three or more. A part of the first imaging system and a part of the second imaging system may be composed of common elements.

[0026] The first illumination system is configured to project first illumination light onto the anterior segment of the eye to be examined. The first illumination light may be, for example, infrared light (near-infrared light) or visible light such as white light. The direction in which the first illumination light is projected onto the anterior segment may be arbitrary. For example, the first illumination light may be projected onto the anterior segment from the front, or the first illumination light may be projected onto the anterior segment obliquely. The first illumination light is used, for example, for the first alignment (coarse alignment) described later.

[0027] The second illumination system is configured to project second illumination light onto the anterior segment of the eye to be examined from the front. For example, the second illumination light may be a light beam emitted toward the anterior segment along the optical axis of the second illumination system, or may be slit light. The second illumination light is typically visible light such as white light, but may be infrared light (near-infrared light) or the like. The second illumination light is used, for example, for the second alignment (fine alignment) described later.

[0028] The first imaging system is configured to image the anterior segment of the eye to be examined from the front. The image (front image of the anterior segment) generated by the first imaging system is used, for example, for the first alignment (coarse alignment) described later.

[0029] A pair of second imaging systems are configured to image the anterior segment of the eye to be examined obliquely and from different directions. That is, one of the second imaging systems is configured to image the anterior segment from a direction other than the frontal direction, and the other second imaging system is configured to image the anterior segment from another direction other than the frontal direction. The inclination direction of each second imaging system with respect to the frontal direction may be, for example, the short side direction of the cross section of the slit light projected by the second illumination system (the width direction of the slit light). That is, each second imaging system may be configured to image the cross section where the slit light is projected from an obliquely lateral direction. Also, the pair of second imaging systems may be controlled (synchronized) to perform imaging substantially simultaneously. The images (cross-sectional images of the anterior segment) generated by the pair of second imaging systems are used, for example, for the second alignment (precision alignment) described later.

[0030] The second illumination system and each of the pair of second imaging systems are configured as a shine-proof optical system that satisfies the shine-proof condition. That is, the combination of the second illumination system and one of the second imaging optical systems is configured as one shine-proof optical system, and the combination of the second illumination system and the other second imaging optical system is configured as another shine-proof optical system.

[0031] The moving mechanism is configured to move the illumination unit and the imaging unit.

[0032] The processor executes a first alignment process, a second alignment process, and an imaging process. The second alignment process is executed after the first alignment process, and the imaging process is executed after the second alignment process. The second alignment process may be executed immediately after the first alignment process, or another process may be executed between the first alignment process and the second alignment process. Similarly, the imaging process may be executed immediately after the second alignment process, or another process may be executed between the second alignment process and the imaging process.

[0033] In the first alignment process, the processor controls the first illumination system to project first illumination light onto the anterior eye part, and causes the anterior eye part onto which the first illumination light is projected to be photographed from the front by the first imaging system. Further, the processor analyzes the frontal image (first anterior eye part image) acquired by the first imaging system to obtain the relative positions (first relative positions) of the illumination unit and the imaging unit with respect to the eye to be examined. In addition, the processor controls the movement mechanism based on the first relative positions. For example, the processor controls the movement mechanism to move the illumination unit and the imaging unit so as to cancel out the first relative positions (in other words, so that the deviation between the position related to the eye to be examined and the positions related to the illumination unit and the imaging unit disappears). Thereby, alignment (first alignment) based on the frontal image acquired using the first illumination system and the first imaging system is executed.

[0034] In the second alignment process, the processor controls the second illumination system to project second illumination light onto the anterior eye part, and causes the anterior eye part onto which the second illumination light is projected to be photographed obliquely from the front by a pair of second imaging systems. Further, the processor analyzes the pair of shine-proof images (pair of second anterior eye part images) acquired by the second imaging systems to obtain the relative positions (second relative positions) of the illumination unit and the imaging unit with respect to the eye to be examined. In addition, the processor controls the movement mechanism based on the second relative positions. For example, the processor controls the movement mechanism to move the illumination unit and the imaging unit so as to cancel out the second relative positions (in other words, so that the deviation between the position related to the eye to be examined and the positions related to the illumination unit and the imaging unit disappears). Thereby, alignment (second alignment) based on the pair of anterior eye part images (pair of shine-proof images) acquired using the second illumination system and the pair of second imaging systems is executed.

[0035] In the imaging process, the processor executes a combination of a process of controlling a second illumination system so as to project slit light onto the anterior eye part from the front, a process of controlling a pair of second imaging systems so as to generate time-series images of the anterior eye part onto which the slit light has been projected, and a process of controlling a moving mechanism so as to move the illumination unit and the imaging unit in the width direction of the slit light (slit light width direction). As a result, an anterior eye part scan using slit light is executed, and a series of anterior eye part images (a series of shine-proof images) are collected. Note that, in the imaging process, time-series images may be generated using both of the pair of second imaging systems, or time-series images may be generated using only one of the second imaging systems.

[0036] The ophthalmic device according to the first aspect is configured to gradually execute alignment of a scan unit (second illumination system and second imaging system) that performs an anterior eye part scan using slit light. As described above, the angle of view of each shine-proof image obtained by the scan unit is narrow, and alignment using the same is not easy. In this aspect, before the second alignment using the scan unit, a first alignment using a first illumination system and a first imaging system different from the scan unit is executed. Thereby, it is possible to smooth and facilitate the start of the second alignment using the scan unit, and it is possible to improve the probability of successful alignment of the scan unit. Therefore, according to this aspect, it is possible to cause an ophthalmic device that performs an anterior eye part scan with slit light to execute high-quality alignment.

[0037] The second aspect of the embodiment provides an example of the stepwise alignment process (first alignment process and second alignment process) in the first aspect. This aspect is the ophthalmic device of the first aspect, and in the first alignment process, the processor executes a process so that Purkinje images due to corneal reflection of second illumination light are depicted in each of a pair of second anterior eye part images obtained by a pair of second imaging systems. Note that the first alignment process of this aspect can also be expressed, for example, as follows.

[0038] In the first alignment process, the processor executes the first alignment process such that the Purkinje image due to the corneal reflection of the second illumination light is included in the range (imaging field, imaging visual field, angle of view) imaged by the pair of second imaging systems (in other words, such that the Purkinje image is arranged in the range, induced in the range, or moved to the range).

[0039] In the first alignment process, the processor executes the first alignment process such that the Purkinje image due to the corneal reflection of the second illumination light is included in the range (illumination range) where the slit light for anterior eye segment scanning is projected (in other words, such that the Purkinje image is arranged in the range, induced in the range, or moved to the range).

[0040] In the first alignment process, the processor executes the first alignment process such that the corneal apex of the eye to be examined is arranged on the focal plane of the pair of second imaging systems.

[0041] In the first alignment process, the processor executes the first alignment process such that the corneal apex of the eye to be examined is arranged in the range (illumination range) where the slit light for anterior eye segment scanning is projected.

[0042] In the second alignment process executed after the first alignment process as described above, the processor analyzes each of the pair of second anterior eye segment images obtained by imaging the anterior eye segment onto which the second illumination light is projected with the pair of second imaging systems to detect a pair of Purkinje images. Further, the processor obtains the relative position (second relative position) of the illumination unit and the imaging unit with respect to the eye to be examined based on the detected pair of Purkinje images.

[0043] The ophthalmic device according to the second aspect performs the first alignment process so that Purkinje images are drawn on a pair of second anterior eye images obtained by a pair of second imaging systems, and then performs the second alignment process using these Purkinje images. As a result, it becomes possible to smoothly and easily start the second alignment using the Purkinje images. Therefore, according to this aspect, it becomes possible to execute high-quality alignment for an ophthalmic device that performs anterior eye scanning with slit light.

[0044] The third aspect of the embodiment provides an example of the second alignment process in the second aspect. This aspect is the ophthalmic device of the second aspect, and the processor, in the second alignment process, based on the coordinates (position information) of a pair of Purkinje images in a pair of second anterior eye images obtained by photographing the anterior eye on which the second illumination light is projected with a pair of second imaging systems, obtains the three-dimensional relative positions of the illumination unit and the imaging unit with respect to the eye to be examined. Further, the processor executes control of the movement mechanism based on the second relative position including the obtained three-dimensional relative position. As a result, the second alignment process is executed so that the second relative position is canceled, in other words, so that the deviation between the position regarding the eye to be examined and the positions regarding the illumination unit and the imaging unit disappears.

[0045] The three-dimensional relative position obtained from the Purkinje image may be, for example, a combination of the position in the moving direction of the illumination unit and the imaging unit moved by the movement mechanism, the position in a certain direction perpendicular to this moving direction, and the position in a direction perpendicular to both of these two directions. More generally, the three-dimensional relative position may be a position defined by a predetermined three-dimensional orthogonal coordinate system.

[0046] The second relative position may include only the three-dimensional relative position obtained from the Purkinje image, or may further include other position information. For example, the second relative position may include a three-dimensional relative position (three-dimensional position information) representing the position of the eye under examination in each direction of the three coordinate axes of a predetermined three-dimensional orthogonal coordinate system, and a rotational position (angular position information) representing the position of the eye under examination that changes due to eye rotation movement. The method for obtaining the angular position information may be arbitrary, and for example, it may be the method described in Japanese Patent Application Laid-Open No. 2023-24761.

[0047] According to the ophthalmic apparatus according to the third aspect, it is possible to provide one preferred example of a process for obtaining the three-dimensional relative position of the illumination unit and the imaging unit with respect to the eye under examination in the second alignment process using the second illumination system and the pair of second imaging systems.

[0048] The fourth aspect of the embodiment provides one example of the second alignment process in the third aspect. This aspect is the ophthalmic apparatus of the third aspect, and the pair of second imaging systems are arranged to be inclined in the slit light width direction by symmetrical angles with respect to the projection direction of the slit light onto the anterior segment of the eye under examination.

[0049] In other words, in this aspect, the optical axis of one of the second imaging systems is inclined by a certain angle in the slit light width direction (the moving direction of the illumination unit and the imaging unit by the moving mechanism) with respect to the projection direction of the light (the second illumination light, the slit light) projected onto the anterior segment by the second illumination system (that is, the optical axis of the second illumination system), and the optical axis of the other second imaging system is inclined by the same angle in the direction opposite to the optical axis of the one imaging system with respect to the optical axis of the second illumination system.

[0050] Furthermore, in this aspect, the processor obtains the three-dimensional relative position of the illumination unit and the imaging unit with respect to the eye under examination based on the coordinates (position information) of the pair of Purkinje images in the pair of second anterior segment images obtained by imaging the anterior segment onto which the second illumination light is projected with the pair of second imaging systems in the second alignment process and the reference information created in advance.

[0051] According to the ophthalmic apparatus according to the fourth aspect, regarding the process of obtaining the three-dimensional relative positions of the illumination unit and the imaging unit with respect to the eye to be examined in the second alignment process using the second illumination system and the pair of second imaging systems, one preferred example can be provided.

[0052] The fifth aspect of the embodiment provides one example of the second alignment process in the fourth aspect. This aspect is the ophthalmic apparatus of the fourth aspect, and the reference information records the relationship between the coordinates in the slit light width direction in the images generated by the pair of second imaging systems and the displacements of the pair of second imaging systems in the slit light width direction and the slit light projection direction with respect to a predetermined reference position (optical origin). This reference information is created, for example, by computer simulation (optical simulation) of the relationship between the positions of the Purkinje images in the pair of second anterior eye segment images obtained by the pair of second imaging systems and the displacements with respect to the optical origin.

[0053] Furthermore, in this aspect, the processor, in the second alignment process, determines the displacements corresponding to the coordinates of the pair of Purkinje images in the pair of second anterior eye segment images obtained by imaging the anterior eye segment onto which the second illumination light is projected with the pair of second imaging systems (that is, the displacements of the pair of second imaging systems in the slit light width direction and the slit light projection direction with respect to the optical origin) based on the reference information, thereby obtaining the relative position in the slit light width direction and the relative position in the slit light projection direction among the three-dimensional relative positions of the illumination unit and the imaging unit with respect to the eye to be examined.

[0054] According to the ophthalmic apparatus according to the fifth aspect, regarding the process of obtaining the three-dimensional relative positions of the illumination unit and the imaging unit with respect to the eye to be examined in the second alignment process using the second illumination system and the pair of second imaging systems, one preferred example can be provided.

[0055] The sixth aspect of the embodiment provides an example of the second alignment process in the third to fifth aspects. This aspect is an ophthalmic device according to any of the third to fifth aspects, and the processor, in the second alignment process, based on the magnification (imaging magnification, optical magnification) of the pair of second imaging systems, determines the relative position in the direction (slit light length direction) perpendicular to both the slit light projection direction and the slit light width direction among the three-dimensional relative positions of the illumination unit and the imaging unit with respect to the eye to be examined.

[0056] According to the ophthalmic device according to the sixth aspect, it is possible to provide a preferred example of the process of determining the three-dimensional relative position of the illumination unit and the imaging unit with respect to the eye to be examined in the second alignment process using the second illumination system and the pair of second imaging systems.

[0057] By combining the fifth aspect and the sixth aspect, it is possible to determine the relative position in the slit light projection direction, the relative position in the slit light width direction, and the relative position in the slit light length direction. That is, by combining the fifth aspect and the sixth aspect, it is possible to provide a preferred example of the process of determining the three-dimensional relative position of the illumination unit and the imaging unit with respect to the eye to be examined defined by the three-dimensional coordinate system spanned by the three coordinate axes of the coordinate axis in the slit light projection direction, the coordinate axis in the slit light width direction, and the coordinate axis in the slit light length direction.

[0058] The seventh aspect of the embodiment provides an example of the first alignment process in the first to sixth aspects. This aspect is an ophthalmic device according to any of the first to sixth aspects, and the processor, in the first alignment process, analyzes the first anterior eye image obtained by imaging the anterior eye part of the eye to be examined onto which the first illumination light is projected with the first imaging system, thereby calculating the focus degree for a predetermined region of the anterior eye part.

[0059] The area of the anterior eye segment considered in the calculation of the focusing degree may be any area (part, position, tissue) of the anterior eye segment, for example, the pupil or a part thereof, or the iris or a part thereof. The focusing degree may be any parameter indicating how well focused the examined eye is with respect to the area. In other words, the focusing degree may be any parameter indicating the focusing state of the examined eye with respect to the area (the relative positional relationship between the area and the focus, the convergence state of the returning light from the area).

[0060] Furthermore, the processor obtains the relative position in the projection direction of the slit light with respect to the anterior eye segment of the examined eye based on the calculated focusing degree. Then, the processor controls the moving mechanism based on the first relative position including the relative position in the projection direction of the slit light obtained. Thereby, the first alignment process is executed so that the first relative position is canceled, in other words, so that the deviation between the position regarding the examined eye and the positions regarding the illumination unit and the imaging unit disappears. The first relative position may include only the relative position in the projection direction of the slit light obtained from the focusing degree, or may further include other position information (for example, the relative position in the slit light width direction and / or the relative position in the slit light length direction). Also, the first relative position may include the rotational position (angular position information) representing the position of the examined eye that changes due to the rotational movement of the eyeball.

[0061] According to the ophthalmic apparatus according to the seventh aspect, a preferred example can be provided for the first alignment process using the first illumination system and the first imaging system.

[0062] The eighth aspect of the embodiment provides an example of the first alignment process in the seventh aspect. This aspect is an ophthalmic device according to the seventh aspect, and in the first alignment process, the processor calculates the defocus degree from the first anterior eye segment image obtained by photographing the anterior eye segment of the eye to be examined onto which the first illumination light is projected with the first imaging system, in order to determine the target position (destination) of the illumination unit and the imaging unit in the slit light projection direction, and executes a combined process of a process of moving the illumination unit and the imaging unit in the slit light projection direction by controlling the movement mechanism.

[0063] The mode of combination of the defocus degree calculation process and the movement process may be arbitrary. For example, the defocus degree calculation process and the movement process may be performed alternately, or the movement process may be performed after satisfying a predetermined condition by the defocus degree calculation process, or the defocus degree calculation process may be performed after satisfying a predetermined condition by the movement process, or the movement process may be performed by evaluating the defocus degree obtained by the defocus degree calculation process, or the defocus degree calculation process may be performed by evaluating the positions of the illumination unit and the imaging unit moved by the movement process, or only a part of any of these modes may be performed, or at least partially combining two or more of these modes may be performed.

[0064] According to the ophthalmic device according to the eighth aspect, one suitable example can be provided for the first alignment process using the first illumination system and the first imaging system.

[0065] The ninth aspect of the embodiment provides an example of the first alignment process in the eighth aspect. This aspect is an ophthalmic device according to the eighth aspect, and in the first alignment process, the processor applies a Laplacian filter to the first anterior eye segment image obtained by photographing the anterior eye segment of the eye to be examined onto which the first illumination light is projected with the first imaging system to obtain a dispersion value. The processor determines the target position of the illumination unit and the imaging unit in the slit light projection direction by searching for the position in the slit light projection direction at which the dispersion value thus obtained becomes maximum by a combined process of a process of calculating the defocus degree and a process of moving the illumination unit and the imaging unit in the slit light projection direction.

[0066] The ophthalmic apparatus according to the ninth aspect provides a preferred example of the process for determining the moving target positions of the illumination unit and the imaging unit in the slit light projection direction. Therefore, according to the ophthalmic apparatus according to the ninth aspect, a preferred example can be provided for the first alignment process using the first illumination system and the first imaging system.

[0067] The tenth aspect of the embodiment provides an example of the first alignment process in the seventh aspect. This aspect is the ophthalmic apparatus of the seventh aspect, and the processor, in the first alignment process, uses the dispersion value obtained by applying a Laplacian filter to the first anterior eye segment image acquired by photographing the anterior eye segment of the eye to be examined onto which the first illumination light is projected, as the focusing degree for a predetermined region of the anterior eye segment.

[0068] According to the ophthalmic apparatus according to the tenth aspect, a preferred example can be provided for the first alignment process using the first illumination system and the first imaging system.

[0069] The eleventh aspect of the embodiment provides an example of the first alignment process in the first to tenth aspects. This aspect is the ophthalmic apparatus of any one of the first to tenth aspects, and the processor, in the first alignment process, analyzes the first anterior eye segment image acquired by photographing the anterior eye segment of the eye to be examined onto which the first illumination light is projected, to identify the image position corresponding to a predetermined feature position of the anterior eye segment of the eye to be examined. This feature position may be any position of the anterior eye segment, for example, the position of the pupil or a part thereof, or the position of the iris or a part thereof.

[0070] Furthermore, the processor obtains the relative position in the two-dimensional direction perpendicular to the projection direction of the slit light with respect to the anterior eye segment of the eye to be examined, based on the image position identified from the first anterior eye segment image. This two-dimensional direction consists of two directions on a plane perpendicular to the slit light projection direction, and may be, for example, the slit light width direction and the slit light length direction described above.

[0071] Then, based on the first relative position including the relative position obtained in the two-dimensional direction perpendicular to the slit light projection direction, the processor executes control of the moving mechanism. As a result, the first alignment process is executed so that the first relative position is canceled out, in other words, so that the deviation between the position regarding the eye to be examined and the positions regarding the illumination unit and the imaging unit disappears. The first relative position may include only the relative position in the two-dimensional direction perpendicular to the slit light projection direction, or may further include other position information (for example, the relative position in the slit light projection direction). Further, the first relative position may include a rotational position (angular position information) representing the position of the eye to be examined that changes due to the eye rotation movement.

[0072] According to the ophthalmic apparatus according to the eleventh aspect, a preferred example of the first alignment process using the first illumination system and the first imaging system can be provided.

[0073] The twelfth aspect of the embodiment provides an example of the first alignment process in the first to sixth aspects. This aspect is an ophthalmic apparatus according to any one of the first to sixth aspects, and in the first alignment process, the processor first executes a process for alignment in a two-dimensional direction (for example, the slit light width direction and the slit light length direction) perpendicular to the slit light projection direction, and then executes a process for alignment in the slit light projection direction.

[0074] First, in order to perform alignment in the two-dimensional direction perpendicular to the slit light projection direction, the processor executes the same process as in the eleventh aspect. That is, the processor analyzes the first anterior eye image obtained by photographing the anterior eye part of the eye to be examined onto which the first illumination light is projected with the first imaging system to identify the image position corresponding to the predetermined feature position of the anterior eye part, obtains the relative position in the two-dimensional direction perpendicular to the slit light projection direction based on the identified image position, and executes control of the moving mechanism based on the relative position obtained for the two-dimensional direction. As a result, alignment in the two-dimensional direction perpendicular to the slit light projection direction is performed.

[0075] After performing alignment in the two-dimensional direction perpendicular to the slit light projection direction, the processor executes the same processing as in the seventh aspect in order to perform alignment in the slit light projection direction. That is, the processor analyzes a first anterior eye image obtained by photographing the anterior segment of the eye to which the first illumination light is projected with the first imaging system, calculates the focus degree for a predetermined region of the anterior segment, obtains the relative position in the slit light projection direction based on the calculated focus degree, and executes control of the moving mechanism based on the relative position obtained for the slit light projection direction. Thereby, alignment in the slit light projection direction is performed. Note that any one of the alignment processes of the eighth to tenth aspects can be combined with the alignment process in the slit light projection direction of this aspect.

[0076] The first anterior eye image processed by the alignment in the slit light projection direction is a different image from the first anterior eye image processed by the alignment in the two-dimensional direction perpendicular to the slit light projection direction. Typically, the first anterior eye image processed by the alignment in the slit light projection direction is an anterior eye image obtained using the first illumination system and the second imaging system after the alignment in the two-dimensional direction perpendicular to the slit light projection direction is completed. Thereby, since alignment in the slit light projection direction can be performed using the first anterior eye image obtained in a state where alignment in the two-dimensional direction perpendicular to the slit light projection direction has been performed, it becomes possible to perform alignment in the slit light projection direction with higher quality.

[0077] According to the ophthalmic apparatus according to the twelfth aspect, a preferred example can be provided for the first alignment process using the first illumination system and the first imaging system.

[0078] The 13th aspect of the embodiment provides an example of the second alignment process in the 2nd to 12th aspects. This aspect is an ophthalmic device according to any one of the 2nd to 12th aspects, and in the second alignment process, the processor causes the first imaging system to acquire a third anterior eye image in parallel with the acquisition of a pair of second anterior eye images using the second illumination system and the pair of second imaging systems. Thereby, for the second alignment, a pair of second anterior eye images (shine-proof images) and a third anterior eye image (frontal image) are acquired in parallel.

[0079] The processor applies an analysis process for detecting Purkinje images to each of the pair of second anterior eye images acquired in parallel with the third anterior eye image.

[0080] When Purkinje images are detected from both of the pair of second anterior eye images acquired in parallel with the third anterior eye image, the processor executes the second alignment process according to, for example, any one of the 2nd to 12th aspects.

[0081] When Purkinje images are not detected from both of the pair of second anterior eye images acquired in parallel with the third anterior eye image, the processor causes, for example, the acquisition of the pair of second anterior eye images (and the acquisition of the third anterior eye image by the first imaging system) to be executed again by the second illumination system and the pair of second imaging systems.

[0082] When a Purkinje image is not detected from one of the pair of second anterior eye images acquired in parallel with the third anterior eye image and a Purkinje image is detected from the other second anterior eye image, the processor analyzes the other second anterior eye image from which the Purkinje image is detected and the third anterior eye image to obtain the second relative positions of the illumination unit and the imaging unit with respect to the eye to be examined.

[0083] The ophthalmic apparatus according to the 13th aspect operates so as to execute the second alignment process using a combination of the other second anterior eye image and the third anterior eye image when the Purkinje image is not reflected in one of the pair of second anterior eye images. Accordingly, the possibility that the second alignment ends in failure is reduced. According to the ophthalmic apparatus of the present aspect, a preferred example can be provided for the second alignment process using the second illumination system and the second imaging system.

[0084] The 14th aspect of the embodiment provides a modification of the 1st aspect. The 1st aspect includes two or more second imaging systems and is configured to execute the second alignment using these second imaging systems, whereas the 14th aspect includes one (or two or more) second imaging systems and is configured to execute the second alignment using the first imaging system and the second imaging system. Specifically, the ophthalmic apparatus of the 14th aspect is configured as follows.

[0085] The 14th aspect is an ophthalmic apparatus including an illumination unit, an imaging unit, a movement mechanism, and a processor.

[0086] The illumination unit is configured to project illumination light onto the eye to be examined. The illumination unit includes a first illumination system and a second illumination system. The first illumination system and the second illumination system may be separate elements or the same element. Also, a part of the first illumination system and a part of the second illumination system may be configured by a common element.

[0087] The imaging unit is configured to image the eye to be examined. The imaging unit includes a first imaging system and a second imaging system. A part of the first imaging system and a part of the second imaging system may be configured by a common element.

[0088] The first illumination system is configured to project first illumination light onto the anterior eye segment of the eye to be examined. The first illumination light may be, for example, infrared light (near-infrared light) or visible light such as white light. The direction in which the first illumination light is projected onto the anterior eye segment may be arbitrary. For example, the first illumination light may be projected onto the anterior eye segment from the front, or the first illumination light may be projected onto the anterior eye segment obliquely. The first illumination light is used, for example, for the first alignment (coarse alignment).

[0089] The second illumination system is configured to project second illumination light onto the anterior eye segment of the eye to be examined from the front. For example, the second illumination light may be a light beam emitted toward the anterior eye segment along the optical axis of the second illumination system, or may be slit light. The second illumination light is used, for example, for the second alignment (fine alignment).

[0090] The first imaging system is configured to image the anterior eye segment of the eye to be examined from the front. The image (front image of the anterior eye segment) generated by the first imaging system is used, for example, for the first alignment (coarse alignment).

[0091] The second imaging system is configured to image the anterior eye segment of the eye to be examined obliquely. The inclination direction of the second imaging system with respect to the front direction may be, for example, the short side direction of the cross section of the slit light projected by the second illumination system (slit light width direction). That is, the second imaging system may be configured to image the cross section on which the slit light is projected from an obliquely lateral direction. The image (cross-sectional image of the anterior eye segment) generated by the second imaging system is used, for example, for the fine alignment described later.

[0092] The second illumination system and the second imaging system are configured as a shine-proof optical system that satisfies the shine-proof conditions.

[0093] The moving mechanism is configured to move the illumination unit and the imaging unit.

[0094] The processor executes a first alignment process, a second alignment process, and a photographing process. The second alignment process is executed after the first alignment process, and the photographing process is executed after the second alignment process. The second alignment process may be executed immediately after the first alignment process, or another process may be executed between the first alignment process and the second alignment process. Similarly, the photographing process may be executed immediately after the second alignment process, or another process may be executed between the second alignment process and the photographing process.

[0095] In the first alignment process, the processor controls the first illumination system to project first illumination light onto the anterior eye part, and causes the first imaging system to photograph the anterior eye part onto which the first illumination light has been projected from the front. Further, the processor analyzes the anterior eye part image (front image) acquired by the first imaging system to obtain the relative positions (first relative positions) of the illumination unit and the imaging unit with respect to the eye to be examined. In addition, the processor controls the movement mechanism based on the first relative positions. For example, the processor controls the movement mechanism to move the illumination unit and the imaging unit so as to cancel out the first relative positions (in other words, so that the deviation between the position regarding the eye to be examined and the positions regarding the illumination unit and the imaging unit disappears). Thereby, alignment (first alignment) based on the front image acquired using the first illumination system and the first imaging system is executed.

[0096] In the second alignment process, the processor controls the second illumination system to project second illumination light onto the anterior eye part, causes the anterior eye part onto which the second illumination light is projected to be photographed from the front by the first imaging system, and causes it to be photographed obliquely from the side by the second imaging system. Further, the processor analyzes a pair of anterior eye part images acquired by the first imaging system and the second imaging system, that is, the anterior eye part image (front image) acquired by the first imaging system and the anterior eye part image (shine-proof image) acquired by the second imaging system, and obtains the relative positions (second relative positions) of the illumination unit and the imaging unit with respect to the eye to be examined. In addition, the processor controls the movement mechanism based on the second relative position. For example, the processor controls the movement mechanism to move the illumination unit and the imaging unit so as to cancel the second relative position (in other words, so that the deviation between the position related to the eye to be examined and the positions related to the illumination unit and the imaging unit disappears). Thereby, alignment (second alignment) based on a pair of anterior eye part images (front image and shine-proof image) acquired using the second illumination system, the first imaging system, and the second imaging system is executed.

[0097] In the imaging process, the processor executes a combination of a process of controlling the second illumination system to project slit light onto the anterior eye part from the front, a process of controlling the second imaging system to generate a time-series image of the anterior eye part onto which the slit light is projected, and a process of controlling the movement mechanism to move the illumination unit and the imaging unit in the width direction of the slit light (slit light width direction). Thereby, anterior eye part scanning using slit light is executed, and a series of anterior eye part images (a series of shine-proof images) are collected.

[0098] The ophthalmic apparatus according to the 14th aspect is configured to gradually perform alignment of a scanning unit (a second illumination system and a second imaging system) that performs anterior segment scanning using slit light. As described above, the angular field of view of each shine-proof image obtained by the scanning unit is narrow, and alignment using it is not easy. In this aspect, before the second alignment using the scanning unit (and the first imaging system), a first alignment using a first illumination system and a first imaging system different from the scanning unit is performed. Thereby, it is possible to smooth and facilitate the start of the second alignment using the scanning unit, and it is possible to improve the probability of successful alignment of the scanning unit. Therefore, according to this aspect, it is possible to cause an ophthalmic apparatus that performs anterior segment scanning with slit light to perform high-quality alignment.

[0099] Any two or more matters regarding the 1st to 14th aspects can be at least partially combined. Also, any matter described in the present disclosure can be at least partially combined with the 1st to 14th aspects. The method of the aspect obtained by such a combination exhibits the operational effects based on each combined matter and also exhibits the synergistic operational effects of the two or more combined matters.

[0100] The 15th aspect of the embodiment provides an invention of a method corresponding to the ophthalmic apparatus of the 1st aspect. The method of this aspect is a method for controlling an ophthalmic apparatus for photographing the anterior segment of an eye to be examined.

[0101] The ophthalmic device controlled by the method of this aspect includes an illumination unit, an imaging unit, a moving mechanism, and a processor. The illumination unit includes a first illumination system that projects first illumination light onto the anterior eye segment of the eye to be examined, and a second illumination system that projects second illumination light onto the anterior eye segment of the eye to be examined from the front. The imaging unit includes a first imaging system that images the anterior eye segment of the eye to be examined from the front, and a pair of second imaging systems that image the anterior eye segment of the eye to be examined obliquely and from different directions. The moving mechanism moves the illumination unit and the imaging unit. Each of the second illumination system and the pair of second imaging systems is configured as a shine-proof optical system that satisfies the shine-proof condition. The method of this aspect includes the following series of steps.

[0102] The first step is to control the first illumination system to project first illumination light onto the anterior eye segment of the eye to be examined, and to control the first imaging system to acquire a first anterior eye segment image.

[0103] The second step is to cause the processor to execute a first alignment process. The first alignment process includes a process of analyzing the first anterior eye segment image acquired in the first step to obtain a first relative position of the illumination unit and the imaging unit with respect to the eye to be examined, and a process of controlling the moving mechanism based on the obtained first relative position.

[0104] The third step is, after the first alignment process, to control the second illumination system to project second illumination light onto the anterior eye segment of the eye to be examined, and to control the pair of second imaging systems to acquire a pair of second anterior eye segment images.

[0105] The fourth step is to cause the processor to execute a second alignment process. The second alignment process includes a process of analyzing the pair of second anterior eye segment images acquired in the third step to obtain a second relative position of the illumination unit and the imaging unit with respect to the eye to be examined, and a process of controlling the moving mechanism based on the obtained second relative position.

[0106] In the fifth step, after the second alignment, the processor is made to execute imaging processing. The imaging processing is a combined process of controlling the second illumination system so as to project slit light from the front onto the anterior segment of the eye to be examined, controlling a pair of second imaging systems so as to generate time-series images of the anterior segment of the eye to which the slit light is projected, and controlling a moving mechanism so as to move the illumination unit and the imaging unit in the width direction of the slit light. In the imaging processing, time-series images may be generated using both of the pair of second imaging systems, or may be generated using only one of the second imaging systems.

[0107] According to the method according to the 15th aspect, similarly to the ophthalmic apparatus according to the 1st aspect, it becomes possible to execute high-quality alignment on an ophthalmic apparatus that performs anterior segment scanning with slit light.

[0108] Any matter regarding the 1st to 14th aspects can be at least partially combined with the 15th aspect. Also, any matter described in the present disclosure can be at least partially combined with the 15th aspect. The method of the aspect obtained by such a combination exhibits the operational effects based on each combined matter, and also exhibits the synergistic operational effects of two or more combined matters.

[0109] The 16th aspect of the embodiment provides an invention of a method corresponding to the ophthalmic apparatus of the 14th aspect. The method of this aspect is a method of controlling an ophthalmic apparatus for imaging the anterior segment of the eye to be examined.

[0110] The ophthalmic device controlled by the method of this aspect includes an illumination unit, an imaging unit, a movement mechanism, and a processor. The illumination unit includes a first illumination system that projects first illumination light onto the anterior eye segment of the eye to be examined, and a second illumination system that projects second illumination light onto the anterior eye segment of the eye to be examined from the front. The imaging unit includes a first imaging system that images the anterior eye segment of the eye to be examined from the front, and a second imaging system that images the anterior eye segment of the eye to be examined obliquely. The movement mechanism moves the illumination unit and the imaging unit. The second illumination system and the second imaging system are configured as a shine-proof optical system that satisfies the shine-proof conditions. The method of this aspect includes the following series of steps.

[0111] The first step is to control the first illumination system to project first illumination light onto the anterior eye segment of the eye to be examined, and to control the first imaging system to acquire a first anterior eye segment image.

[0112] The second step is to cause the processor to execute a first alignment process. The first alignment process includes a process of analyzing the first anterior eye segment image acquired in the first step to obtain a first relative position of the illumination unit and the imaging unit with respect to the eye to be examined, and a process of controlling the movement mechanism based on the obtained first relative position.

[0113] The third step is, after the first alignment process, to control the second illumination system to project second illumination light onto the anterior eye segment of the eye to be examined, and to control the first imaging system and the second imaging system to acquire a pair of anterior eye segment images.

[0114] The fourth step is to cause the processor to execute a second alignment process. The second alignment process includes a process of analyzing the pair of anterior eye segment images acquired in the third step to obtain a second relative position of the illumination unit and the imaging unit with respect to the eye to be examined, and a process of controlling the movement mechanism based on the obtained second relative position.

[0115] In the fifth step, after the second alignment, the processor is made to execute imaging processing. The imaging processing is a combined process of controlling the second illumination system so as to project slit light from the front onto the anterior eye segment of the eye to be examined, controlling the second imaging system so as to generate time-series images of the anterior eye segment of the eye to be examined onto which the slit light is projected, and controlling the moving mechanism so as to move the illumination unit and the imaging unit in the width direction of the slit light.

[0116] According to the method according to the 16th aspect, similar to the ophthalmic device according to the 14th aspect, it becomes possible to perform high-quality alignment on an ophthalmic device that performs anterior eye segment scanning with slit light.

[0117] Any matter regarding the 1st to 14th aspects can be at least partially combined with the 16th aspect. Also, any matter described in the present disclosure can be at least partially combined with the 16th aspect. The method of the aspect obtained by such combination exhibits the operational effects based on each combined matter and also exhibits the synergistic operational effects of two or more combined matters.

[0118] The 17th aspect of the embodiment is a program for causing a computer to execute the method of the 15th or 16th aspect. The computer of the 17th aspect includes the processor of the 15th or 16th aspect.

[0119] According to the program according to the 17th aspect, similar to the method of the 15th or 16th aspect, it becomes possible to perform high-quality alignment on an ophthalmic device that performs anterior eye segment scanning with slit light.

[0120] Any matter regarding the 1st to 15th aspects can be at least partially combined with the 17th aspect. Also, any matter described in the present disclosure can be at least partially combined with the 17th aspect. The program of the aspect obtained by such combination exhibits the operational effects based on each combined matter and also exhibits the synergistic operational effects of two or more combined matters.

[0121] The 18th aspect of the embodiment is a computer-readable non-transitory recording medium on which the program of the 17th aspect is recorded.

[0122] According to the recording medium according to the 18th aspect, similarly to the program of the 17th aspect, it is possible to execute high-quality alignment on an ophthalmic apparatus that performs anterior eye segment scanning with slit light.

[0123] Any matter regarding the 1st to 15th aspects can be at least partially combined with the 18th aspect. Also, any matter described in the present disclosure can be at least partially combined with the 18th aspect. The recording medium of the aspect obtained by such a combination exhibits the operational effects based on each combined matter and also exhibits the synergistic operational effects of two or more combined matters.

[0124] In the present disclosure, various non-limiting aspects including the 1st to 18th aspects are described. In the present disclosure, exemplary aspects of an ophthalmic apparatus, an exemplary aspect of a method for controlling an ophthalmic apparatus, an exemplary aspect of a program, and an exemplary aspect of a recording medium are mainly described. However, the category of the aspects of the embodiment is not limited to these. For example, those skilled in the art will be able to understand that the embodiments according to the present disclosure can provide various aspects of medical methods, various aspects of imaging methods, various aspects of data processing methods, and the like.

[0125] <Ophthalmic Apparatus> Regarding the ophthalmic apparatus according to the embodiment, some non-limiting aspect examples will be described. The ophthalmic apparatus according to the embodiment includes an anterior eye segment scanner of a type that moves a Schlein-proof optical system using slit light as illumination light, but any matter described in the present disclosure may be applied to another type of anterior eye segment scanner. In the present disclosure, some examples of a slit lamp microscope configured to enable anterior eye segment scanning will be described in detail, but the method of anterior eye segment scanning and the applicable configurations are not limited to these examples.

[0126] FIG. 1 shows a configuration example of an ophthalmic apparatus according to one aspect. The ophthalmic apparatus 1 of this aspect is used for anterior eye imaging of the eye E to be examined, and includes an illumination unit 2, an imaging unit 3, a moving mechanism 6, a control unit 7, a data processing unit 8, a communication unit 9, and a user interface (UI) 10. The cornea of the eye E to be examined is denoted by reference numeral Co, the iris by reference numeral Ir, and the lens by reference numeral Cr. The ophthalmic apparatus 1 may further include elements not shown, such as a fixation optical system and an observation system.

[0127] In accordance with common practice in the ophthalmic field, the direction along the axis of the eye E to be examined is defined as the Z direction (Z axis), and the plane perpendicular to the Z direction is defined as the XY plane. The left-right direction (horizontal direction) for the subject is defined as the X direction (X axis), and the direction perpendicular to both the X direction and the Z direction (vertical direction, body axis direction) is defined as the Y direction (Y axis).

[0128] The communication unit 9 performs data communication between the ophthalmic apparatus 1 and other devices. That is, the communication unit 9 transmits data to other devices and receives data transmitted from other devices. The data communication method executed by the communication unit 9 is arbitrary. For example, the communication unit 9 includes one or more of various communication interfaces, such as a communication interface compliant with the Internet, a communication interface compliant with a dedicated line, a communication interface compliant with a LAN, and a communication interface compliant with short-range communication. The data communication may be wired communication or wireless communication.

[0129] The data transmitted or received by the communication unit 9 may be encrypted data. The control unit 7 and / or the data processing unit 8 may include either or both of an encryption processing unit that encrypts the data transmitted by the communication unit 9 and a decryption processing unit that decrypts the data received by the communication unit 9.

[0130] The user interface 10 includes any user interface device such as a display device and an operation device. Users such as doctors, examinees, and assistants can operate the ophthalmic apparatus 1 and input information into the ophthalmic apparatus 1 by using the user interface 10. At least a part of the user interface 10 may be a peripheral device of the ophthalmic apparatus 1.

[0131] The display device displays various information under the control of the control unit 7. The display device may include a flat panel display such as a liquid crystal display (LCD). The operation device includes a device for operating the ophthalmic apparatus 1 and a device for inputting information. The operation device includes, for example, buttons, switches, levers, dials, handles, knobs, mice, keyboards, trackballs, operation panels, etc. A device in which the display device and the operation device are integrated, such as a touch screen, may be used.

[0132] The illumination unit 2 is configured to project illumination light onto the anterior eye part of the eye E to be examined. The illumination system 2 includes a first illumination system 2A and a second illumination system 2B.

[0133] The first illumination system 2A is configured to project first illumination light onto the anterior eye part of the eye E to be examined. The first illumination light is infrared light (near-infrared light) or visible light. The first illumination system 2A projects the first illumination light onto the anterior eye part of the eye E to be examined from a predetermined direction. The projection direction of the first illumination light may be arbitrary. For example, the first illumination light is projected onto the anterior eye part from the front or obliquely.

[0134] The second illumination system is configured to project second illumination light onto the anterior eye part of the eye E to be examined from the front. The second illumination light is visible light (light beam or slit light) emitted toward the anterior eye part along the optical axis of the second illumination system.

[0135] The imaging unit 3 is configured to image the eye E to be examined. The imaging unit 3 includes a first imaging system 3A and a second imaging system 3B.

[0136] The first imaging system 3A is configured to image the anterior segment of the eye E to be examined from the front.

[0137] The second imaging system 3B is configured to image the anterior segment of the eye E to be examined obliquely and from different directions. In this embodiment, the second imaging system 3B includes two second imaging systems 3BL and 3BR (see FIG. 3), but may include three or more.

[0138] As shown in FIG. 2, the first illumination system 2A and the first imaging system 3A form the first imaging unit 4. The first imaging system 3A is disposed at the front position of the eye E to be examined. The optical axis (imaging optical axis) 3Aa of the first imaging system 3A is disposed parallel to the Z direction. The arrangement of the first illumination system 2A may be arbitrary.

[0139] The first imaging unit 4 projects the first illumination light onto the anterior segment of the eye E to be examined by the first illumination system 2A, and images the anterior segment onto which the first illumination light is projected from the front by the first imaging system 3A. Thereby, a front image of the anterior segment of the eye E to be examined is acquired.

[0140] In the example shown in FIG. 3, the second imaging system 3B includes two second imaging systems 3BL and 3BR. The second illumination system 2B, and the second imaging systems 3BL and 3BR, together with the scanning mechanism 5B, form the second imaging unit 5.

[0141] The combination of the second illumination system 2B and the second imaging system 3BL forms a shine-proof optical system that satisfies the shine-proof condition. That is, the second illumination system 2B and the second imaging system 3BL are configured such that the object plane including the optical axis (illumination optical axis) 2Ba of the second illumination system 2B, the principal plane of the optical system of the second imaging system 3BL, and the imaging plane of the imaging element of the second imaging system 3BL intersect on the same straight line. The same applies to the combination of the second illumination system 2B and the second imaging system 3BR.

[0142] The illumination optical axis 2Ba of the second illumination system 2B is arranged parallel to the Z direction. The optical axis (imaging optical axis) 3BLa of the second imaging system 3BL is inclined by an angle θL in a first direction (+X direction or -X direction) defined by the X axis with respect to the illumination optical axis 2Ba. On the other hand, the optical axis (imaging optical axis) 3BRa of the second imaging system 3BR is inclined by an angle θR in a second direction (-X direction or +X direction) opposite to the first direction with respect to the illumination optical axis 2Ba. The angle θL and the angle θR may be equal to each other or different from each other. In this embodiment, the angle θL and the angle θR are assumed to be equal to each other.

[0143] The second imaging unit 5 projects second illumination light onto the anterior eye part of the eye E to be examined by the second illumination system 2B, and images the anterior eye part onto which the second illumination light has been projected obliquely from the side by the second imaging systems 3BL and 3BR. Thereby, a pair of Scheimpflug images of the anterior eye part of the eye E to be examined are acquired.

[0144] Also, the second imaging unit 5 is used for scanning the anterior eye part of the eye E to be examined. The second illumination system 2B and the second imaging systems 3BL and 3BR form a movable unit 5A that is moved by a scanning mechanism 5B. The scanning mechanism 5B moves the movable unit 5A in the X direction. The scanning mechanism 5B includes an actuator such as a motor and a mechanism for moving the movable unit 5A in the X direction by the driving force generated by this actuator.

[0145] In the anterior eye segment scan, the second illumination system 2B projects slit light onto the anterior eye segment of the eye to be examined E from the front. The shape of the cross-section of the slit light projected onto the anterior eye segment (i.e., the projection image of the slit light on the anterior eye segment) is a substantially slit shape (thin line shape, narrow band shape) with the Y direction as the longitudinal direction (slit light length direction) and the X direction as the short side direction (slit width direction). Each of the second imaging systems 3BL and 3BR performs iterative imaging (video imaging) to generate time-series images. The scanning mechanism 5B moves the movable unit 5A in the X direction (slit width direction). By applying the anterior eye segment scan combining these operations to the anterior eye segment of the eye to be examined E, the second imaging unit 5 acquires time-series images collected while moving the projection area of the slit light. That is, the second imaging unit 5 collects a series of shine-proof images in which a plurality of different cross-sections of the anterior eye segment of the eye to be examined E are respectively depicted.

[0146] The series of shine-proof images collected by such an anterior eye segment scan includes the series of shine-proof images collected by the second imaging system 3BL and the series of shine-proof images collected by the second imaging system 3BR. For example, the imaging timing (frame acquisition timing) of the second imaging system 3BL and the imaging timing of the second imaging system 3BR are synchronized with each other. Thus, in the anterior eye segment scan of this example, two groups of shine-proof images obtained by imaging the anterior eye segment of the eye to be examined E from two different directions are acquired, and moreover, the two groups of shine-proof images are temporally associated. Note that the anterior eye segment scan may be performed using only one of the second imaging systems 3BL and 3BR.

[0147] The method of anterior eye segment scanning in this example is the same as that described in Patent Document 2 (Japanese Patent Application Laid-Open No. 2023-49320). Also, the second illumination system 2B and the imaging systems 22L and 22R may have the same configuration as the slit lamp microscope described in Patent Document 2 (Japanese Patent Application Laid-Open No. 2023-49320). In that case, the second illumination system 2B includes an illumination light source that generates visible light, a slit forming portion that forms a slit opening for converting the generated visible light into slit light, an objective lens that projects the formed slit light onto the anterior eye segment of the eye to be examined E, and the like. Also, the second imaging system 3BL includes an optical system including an objective lens, a zoom optical system, and an imaging lens, an imaging element that detects the light guided by this optical system, and the like. The imaging element is an area sensor such as a charge-coupled device (CCD) image sensor or a complementary metal-oxide-semiconductor (CMOS) image sensor. The second imaging system 3BR has the same configuration as the second imaging system 3BL.

[0148] One non-limiting example of the optical system of the ophthalmic apparatus 1 is shown in FIG. 4. The optical system in this example includes an illumination optical system 20, a left imaging optical system 30L and a right imaging optical system 30R, a front imaging optical system 40, and anterior eye segment illumination light sources 50L and 50R.

[0149] The illumination optical system 20 is an example of the second illumination system 2B, and the left imaging optical system 30L and the right imaging optical system 30R are examples of the second imaging system 3B. The left imaging optical system 30L is an example of the second imaging system BL, and the right imaging optical system 30R is an example of the second imaging system BR. Also, the anterior eye segment illumination light sources 50L and 50R are examples of the first illumination system 2A, and the front imaging optical system 40 is an example of the second imaging system 3B.

[0150] Reference numeral 20a indicates the optical axis (illumination optical axis) of the illumination optical system 20, reference numeral 30La indicates the optical axis (left imaging optical axis) of the left imaging optical system 30L, and reference numeral 30Ra indicates the optical axis (right imaging optical axis) of the right imaging optical system 30R. The illumination optical system 20 and the left imaging optical system 30L are arranged such that the illumination optical axis 20a and the left imaging optical axis 30La form an angle θL. The illumination optical system 20 and the right imaging optical system 30R are arranged such that the illumination optical axis 20a and the right imaging optical axis 30Ra form an angle θR. In this embodiment, the angle θL and the angle θR are equal to each other. The position Z0 (coordinate Z0) on the Z-axis indicates the intersection of the illumination optical axis 20a, the left imaging optical axis 30La, and the right imaging optical axis 30Ra.

[0151] The illumination light source 21 of the illumination optical system 20 outputs illumination light (visible light). The illumination light refracted by the positive lens 22 is projected onto the slit forming unit 23. The slit forming unit 23 forms an aperture (slit) that allows a part of the illumination light to pass through. The illumination light (slit light) that has passed through the slit is refracted by the objective lens groups 24 and 25, reflected by the beam splitter 47, and projected onto the anterior eye part of the eye E to be examined.

[0152] The slit forming unit 23 can change the dimensions (slit width, slit length) of the slit. Thereby, the dimensions (width, length) of the slit light projected onto the eye E to be examined can be changed. The slit forming unit 23 can change the orientation of the slit. The illumination optical system 20 may be capable of generating a light beam that travels on the illumination optical axis 20a and is projected onto the eye E to be examined, for example, by changing the form of the aperture of the slit forming unit 23 or by providing another element (light source, optical system, etc.).

[0153] The reflector 31L and the imaging lens 32L of the left imaging optical system 30L guide the light from the anterior eye part onto which the slit light has been projected by the illumination optical system 20 (the light traveling in the direction of the left imaging optical system 30L) to the imaging element 33L. The imaging element 33L receives the guided light on the imaging surface 34L.

[0154] Similarly, the right imaging optical system 30R guides the light from the anterior eye part onto which the slit light is projected by the illumination optical system 20 (the light traveling in the direction of the right imaging optical system 30R) to the imaging element 33R by the reflector 31R and the imaging lens 32R, and receives the light on the imaging surface 34R of the imaging element 33R.

[0155] The object plane along the illumination optical axis 20a, the optical system including the reflector 31L and the imaging lens 32L, and the imaging surface 34L satisfy the Shine-proof condition. Similarly, the object plane along the illumination optical axis 20a, the optical system including the reflector 31R and the imaging lens 32R, and the imaging surface 34R satisfy the Shine-proof condition.

[0156] The anterior eye part illumination light sources 50L and 50R are light-emitting elements that output light for illuminating the anterior eye part, and may be, for example, light-emitting diodes (LEDs) that generate visible light or infrared light (near-infrared light). In this example, two anterior eye part illumination light sources 50L and 50R are provided, but the number may be arbitrary. Also, in this example, the anterior eye part illumination light sources 50L and 50R are respectively arranged outside the left imaging optical system 30L and the right imaging optical system 30R, but the positions where they are provided are arbitrary.

[0157] The front imaging optical system 40 images the anterior eye part of the eye to be examined E from the front. The optical path of the front imaging optical system 40 is coupled coaxially with the optical path of the illumination optical system 20 by the beam splitter 47. The arrangement relationship between the illumination optical system 20 and the front imaging optical system 40 with respect to the beam splitter 47 may be reversed.

[0158] The light from the anterior eye part onto which the illumination light is projected by the anterior eye part illumination light sources 50L and 50R (the light traveling in the direction of the front imaging optical system 40) is guided to the beam splitter 47. The light transmitted through the beam splitter 47 is reflected by the reflector 48, refracted by the objective lens 41, and imaged on the imaging surface of the imaging element 43 (area sensor) by the imaging lens 42.

[0159] Depending on the relationship between the wavelength of the illumination light from the illumination optical system 20 and the wavelengths of the illumination lights from the anterior eye illumination light sources 50L and 50R, a half mirror or a dichroic mirror can be used as the beam splitter 47.

[0160] As described above, the optical system shown in FIG. 4 can perform a first anterior eye imaging using the anterior eye illumination light sources 50L and 50R and the front imaging optical system 40, a second anterior eye imaging using the illumination optical system 20 and the left and right imaging optical systems 30L and 30R, and an anterior eye scan using the illumination optical system 20 and the left and right imaging optical systems 30L and 30R. The first anterior eye imaging is executed for the first alignment process, the second anterior eye imaging is executed for the second alignment process, and the anterior eye scan is executed for the imaging process.

[0161] Returning to the reference of FIG. 1, the moving mechanism 6 moves the illumination unit 2 and the imaging unit 3. The moving mechanism 6 can move the illumination unit 2 and the imaging unit 3 three-dimensionally (i.e., in the X direction, Y direction, and Z direction). The structure (including the illumination unit 2 and the imaging unit 3) moved by the moving mechanism 6 is called an optical head or the like.

[0162] The control unit 7 controls each part of the ophthalmic apparatus 1. For example, the control unit 7 controls elements of the illumination unit 2 (such as a light source, an optical element, a mechanism, etc.), elements of the imaging unit 3 (such as an imaging device, an optical element, a mechanism, etc.), the moving mechanism 6, the data processing unit 8, the communication unit 9, the user interface 10, and the like.

[0163] The control unit 7 includes a processor, a main storage device, an auxiliary storage device, and the like. The auxiliary storage device stores computer programs such as various control programs. These computer programs may be stored in a computer or a storage device accessible by the ophthalmic apparatus 1. The functions of the control unit 7 are realized by the cooperation of software such as control programs and hardware such as a processor.

[0164] The data processing unit 8 executes various data processes. The data to be processed may be either data acquired by the ophthalmic apparatus 1 or data input from the outside.

[0165] The data processing unit 8 includes a processor, a main storage device, an auxiliary storage device, etc. The auxiliary storage device stores computer programs such as various data processing programs. These computer programs may be stored in a computer or a storage device accessible by the ophthalmic apparatus 1. The functions of the data processing unit 8 are realized by the cooperation of software such as data processing programs and hardware such as a processor.

[0166] The processes executed by the data processing unit 8 will be described later together with the processes executed by the control unit 7. The control unit 7 and the data processing unit 8 function as an example of a processor of the ophthalmic apparatus according to the embodiment.

[0167] Some non-limiting operation examples of the ophthalmic apparatus 1 of this aspect will be further described with reference to FIGS. 5 to 7. The flowchart of FIG. 5 shows an outline of the operation example. FIG. 6 shows a specific example of step S2 in FIG. 5. FIG. 7 shows a specific example of step S3 in FIG. 5.

[0168] First, the eye examination information is input to the ophthalmic apparatus 1 (S1). For example, the eye examination information includes a subject identifier and left eye / right eye information, and may further include other information regarding the eye E to be examined (e.g., examination data, image data, electronic medical record information), information regarding the subject (e.g., name, age, gender, examination data, image data, electronic medical record data, medical history, medication history), etc. The input of the eye examination information is performed, for example, via the communication unit 9 and / or using the user interface 10.

[0169] Next, the ophthalmic apparatus 1 performs alignment (auto-alignment) of the optical head with respect to the eye E to be examined (S2). The auto-alignment may be performed using the subject information input in step S1. For example, the initial position of the optical head is determined based on the left eye / right eye information. The auto-alignment is performed, for example, by a series of steps shown in FIG. 6. Some examples of the details of the auto-alignment will be described later.

[0170] When the auto-alignment is completed, the ophthalmic apparatus 1 starts tracking to cause the optical head to follow the movement of the eye E to be examined (S3). By tracking, it is possible to maintain a suitable positional relationship between the eye E to be examined and the optical head achieved by the auto-alignment. The tracking is performed, for example, according to a series of steps shown in FIG. 7. Some examples of the details of the tracking will be described later.

[0171] When a suitable positional relationship between the eye E to be examined and the optical head is maintained, the ophthalmic apparatus 1 applies a scan to the anterior segment of the eye E to be examined (S4). A series of anterior segment images collected by the anterior segment scan are, for example, stored, displayed, and transmitted. Thus, this operation example ends (end).

[0172] Some examples of the auto-alignment in step S2 will be described. Hereinafter, FIG. 6 will be further referred to.

[0173] The auto-alignment includes a first-stage rough alignment and a second-stage fine alignment. The rough alignment is an operation for arranging the illumination unit 2 and the imaging unit 3 within a position range where the fine alignment can be performed. The fine alignment is an operation for arranging the illumination unit 2 and the imaging unit 3 within a position range where the anterior segment scan can be performed. The process for performing the rough alignment is the aforementioned first alignment process, and the process for performing the fine alignment is the second alignment process. This operation example realizes the auto-alignment of an anterior segment scanner with a narrow angle of view by combining the rough alignment and the fine alignment.

[0174] In step S2, the ophthalmic device 1 first starts the rough alignment (S11). The ophthalmic device 1 starts the rough alignment in response to a predetermined trigger. This trigger may be, for example, an instruction operation using the user interface 10 or the completion of step S1.

[0175] When the rough alignment is started, the ophthalmic device 1 starts generating a front image (first anterior eye image) of the anterior eye of the eye E to be examined (S12).

[0176] Specifically, under the control of the control unit 7, the first illumination system 2A starts projecting first illumination light onto the anterior eye of the eye E to be examined, and the first imaging system 3A starts video imaging of the anterior eye of the eye E to be examined.

[0177] The frames (front images) sequentially generated by the first imaging system 3A are sequentially input to the data processing unit 8. The data processing unit 8 analyzes each input frame to detect a pupil image (S13). The frames provided for the detection of the pupil image may be all the frames generated by the first imaging system 3A or only the frames selected by the subsampling process.

[0178] The detection of the pupil image is performed using an arbitrary segmentation method. This segmentation method may be a machine learning-based segmentation method using a convolutional neural network (CNN) or the like, or a segmentation method using threshold processing, histogram, clustering, edge detection, region expansion, or the like, or a combination thereof.

[0179] The ophthalmic device 1 performs rough alignment based on the pupil images sequentially detected in step 13. This rough alignment is alignment in the XY directions (rough XY alignment). In the rough XY alignment, the optical head is moved so that the center of the pupil of the eye E to be examined is located at the center of the front image (S14).

[0180] An example of a frontal image obtained before performing coarse XY alignment is shown in FIG. 8. In the frontal image F shown in FIG. 8, the center of the pupil Ep of the eye E to be examined is located at a position away from the center of the image (frame). By performing coarse XY alignment, as shown in FIG. 9, a frontal image F can be obtained in which the center of the pupil Ep of the eye E to be examined is located at approximately the center of the frame.

[0181] In coarse XY alignment, for example, the data processing unit 8 applies a circular approximation or an elliptical approximation to the contour of the pupil image in the frame, obtains the center position (pupil center position) of the obtained approximate circle or approximate ellipse, and obtains the deviation (deviation direction and deviation amount) of the pupil center position with respect to the frame center. The obtained deviation is sent to the control unit 7. The control unit 7 controls the moving mechanism 6 to move the optical head so as to cancel this deviation. As a result, the illumination unit 2 and the imaging unit 3 are arranged at positions such that the pupil center of the eye E to be examined is drawn at the frame center (or in its vicinity).

[0182] When the coarse XY alignment is completed, the process proceeds to the coarse alignment in the Z direction (coarse Z alignment). Note that the acquisition of the frontal image started in step S12 continues. In the coarse Z alignment, first, under the control of the control unit 7, the data processing unit 8 starts calculating the focus degree for a predetermined region of the anterior eye part of the eye E to be examined (S15).

[0183] In this operation example, the data processing unit 8 analyzes a frontal image of the anterior eye part of the eye E to be examined (the frontal image obtained after the start of the coarse Z alignment) and calculates the focus degree with respect to the iris Ir (pupil) of the anterior eye part of the eye E to be examined.

[0184] The method for calculating the focus degree may be arbitrary. For example, the data processing unit 8 analyzes a frontal image of the anterior eye part of the eye E to be examined, detects image regions corresponding to the iris Ir and the pupil, sets them as regions of interest (ROI), and applies a Laplacian filter to this region of interest to obtain a Laplacian variance value.

[0185] In the rough Z alignment, the ophthalmic apparatus 1 moves the optical head in the Z direction under the control of the control unit 7 together with the calculation of the focusing degree (S15) by the data processing unit 8.

[0186] In this operation example, the ophthalmic apparatus 1 obtains the relationship between the position of the optical head in the Z direction (Z position) and the value of the focusing degree by performing the repeated calculation of the focusing degree and the movement of the optical head in the Z direction in parallel. That is, the ophthalmic apparatus 1 obtains the relationship between the change in the Z position of the optical head and the change in the value of the focusing degree. By using this information, the control unit 7 and the data processing unit 8 search for the Z position of the optical head at which the Laplacian dispersion value is maximized.

[0187] Such a process is described, for example, in the following literature: Pacheco et al. (2000). Diatom autofocusing in brightfield microscopy: A comparative study. Pattern Recognition, Proceedings. 15th International Conference on. 3. 314 - 317 vol.3.

[0188] The ophthalmic apparatus 1 arranges the optical head at the Z position thus searched. As a result, the illumination unit 2 and the imaging unit 3 are arranged at positions that are in focus with the iris Ir of the eye E to be examined (S17).

[0189] The front image F of FIG. 9 described above is an example of an image obtained after performing rough XY alignment and before performing rough Z alignment. Before performing rough Z alignment, since the focus is not on the iris Ir, the contour of the pupil Ep of the eye E to be examined (the boundary between the pupil Ep and the iris Ir) is blurred and not clear. In FIG. 9, this unclear depiction state is shown by a dotted line. By performing rough Z alignment, as shown in FIG. 10, a front image F in which the contour of the pupil Ep is clearly depicted can be obtained. Thus, according to the auto-alignment in step S2, the position alignment of the illumination unit 2 and the imaging unit 3 can be performed so that the center of the pupil Ep is located at approximately the center of the front image F and the pupil Ep and the iris Ir are clearly depicted.

[0190] The fine alignment started in step S18 is performed with reference to the Purkinje image depicted in the shine-proof image obtained by the second illumination system 2B and the second imaging system 3B used for anterior eye segment scanning. The rough alignment described above enables the fine alignment to be executed by adjusting the positions of the illumination unit 2 and the imaging unit 3 so that the Purkinje image is depicted in the shine-proof image.

[0191] The Purkinje image is also called the Purkinje-Sanson image or the Purkinje-Sanson mirror image and is a reflected image of light projected onto the eye. The Purkinje image includes those due to the anterior corneal surface reflection, the posterior corneal surface reflection, the anterior lens surface reflection, and the posterior lens surface reflection. In this operation example, the first Purkinje image due to the anterior corneal surface reflection is referred to.

[0192] When light is projected from the front of the eye E to pass through the corneal apex, it is known that a Purkinje image is formed at a position that is half of the corneal radius of curvature away from the corneal apex in the Z direction. In a standard eye, the Purkinje image is formed at a position approximately 4 millimeters away from the corneal apex in the Z direction toward the fundus. When the positional error between the corneal apex and the pupil center in the XY direction is not large, by performing the rough alignment in this operation example, there is a high possibility that the Purkinje image will be depicted in the shine-proof image obtained by the second illumination system 2B and the second imaging system 3B.

[0193] When the XY positional error between the corneal apex and the pupil center is large due to, for example, corneal deformation caused by a disease or treatment, while projecting light from the front to the eye E to be examined and performing rough alignment, position adjustment can be performed while referring to the position of the Purkinje image. Note that the application of this method is not limited to cases where the XY positional error between the corneal apex and the pupil center is large.

[0194] Also, according to the above rough alignment, since the pupil Ep and the iris Ir can be focused, in the shine-proof image obtained by the second illumination system 2B and the second imaging system 3B, for example, the range from the anterior surface of the cornea to the posterior surface of the lens, which is referred to in image diagnosis, is depicted in a focused state.

[0195] Now, when the rough alignment is completed and the process shifts to the fine alignment (S18), the control unit 7 stops the operations of the first illumination system 2A and the first imaging system 3A used in the rough alignment, and starts the operations of the second illumination system 2B and the second imaging system 3B used in the fine alignment.

[0196] In this operation example, the second illumination system 2B projects infrared coaxial light (IR coaxial light) from the front onto the anterior segment of the eye E to be examined (S19). The infrared coaxial light is infrared light that travels on the optical axis 2Ba of the second illumination system 2B and is projected onto the eye E to be examined.

[0197] Further, the first imaging system 3A starts imaging a video of the anterior segment of the eye E to be examined onto which infrared coaxial light is projected. In this operation example, each of the pair of second imaging systems 3BL and 3BR starts imaging a video. Thereby, generation of a pair of Scheimpflug images by the second imaging systems 3BL and 3BR is started (S20). The pair of second imaging systems 3BL and 3BR generate a pair of Scheimpflug images at a predetermined time interval (frame rate).

[0198] A pair of Scheimpflug images sequentially generated by the pair of second imaging systems 3BL and 3BR are input to the data processing unit 8. The data processing unit 8 analyzes the pair of Scheimpflug images to detect a pair of Purkinje images (S21).

[0199] An example of a pair of Scheimpflug images is shown in FIG. 11. The Scheimpflug image GL is generated by the second imaging system 3BL (left imaging optical system 30L), and the Scheimpflug image GR is generated by the second imaging system 3BR (right imaging optical system 30R). A Purkinje image PuL is depicted in the Scheimpflug image GL, and a Purkinje image PuR is depicted in the Scheimpflug image GR.

[0200] The data processing unit 8 detects a Purkinje image depicted as a bright spot using an image processing method such as threshold processing. Thereby, the position (coordinates) of the Purkinje image PuL in the Scheimpflug image GL is obtained, and the position (coordinates) of the Purkinje image PuR in the Scheimpflug image GR is obtained.

[0201] Based on the coordinates of the Purkinje image PuL and the coordinates of the Scheimpflug image GR, the data processing unit 8 obtains the three-dimensional relative positions of the illumination unit 2 and the imaging unit 3 (particularly, the second illumination system 2B and the second imaging systems 3BL and 3BR) with respect to the eye E to be examined. This calculation is performed by applying, for example, triangulation.

[0202] In this operation example, the second imaging systems 3BL and 3BR are arranged to be inclined at angles symmetric to each other in the X direction with respect to the optical axis 2Ba (Z direction) of the second illumination system 2B (θL = θR). Further, in this operation example, the data processing unit 8 obtains the three-dimensional relative positions of the second illumination system 2B and the second imaging systems 3BL and 3BR based on the coordinates of the pair of Purkinje images PuL and PuR and the reference information created in advance.

[0203] The reference information of this operation example records the relationship of three parameters. Specifically, the reference information of this operation example records the relationship between the X-direction coordinates (X coordinates) in the Shine Purf image generated by the second imaging systems 3BL and 3BR, the X-direction displacement of the second imaging systems 3BL and 3BR with respect to the optical origin, and the Z-direction displacement of the second imaging systems 3BL and 3BR with respect to the optical origin.

[0204] One example of such reference information is shown in FIG. 12. In the reference information of FIG. 12, various positions (positions of Purkinje images) in the Shine Purf image (left image) generated by the second imaging system 3BL and various positions (positions of Purkinje images) in the Shine Purf image (right image) generated by the second imaging system 3BR are represented using a three-dimensional orthogonal coordinate system with the above three parameters as three coordinate axes.

[0205] The reference information of this operation example is created by performing an optical simulation that models the second illumination system 2B and the second imaging systems 3BL and 3BR. The created reference information is stored in the ophthalmic device 1 or a device accessible thereby as a look-up table referred to in precise alignment.

[0206] The data processing unit 8 obtains the displacements (ΔSxl, ΔSyl) from the frame center for the Purkinje image PuL detected from the Shine-proof image (left image) GL in step S21. Similarly, the data processing unit 8 obtains the displacements (ΔSxr, ΔSyr) from the frame center for the Purkinje image PuR detected from the Shine-proof image (right image) GR in step S21. Note that only the displacements in the X direction (X displacements) ΔSxl and ΔSxr may be obtained.

[0207] Based on the reference information, the data processing unit 8 obtains the displacement in the X direction and the displacement in the Z direction corresponding to the pair of X displacements ΔSxl and ΔSxr for the pair of Purkinje images PuL and PuR in the pair of Shine-proof images GL and GR. The obtained displacement in the X direction corresponds to the relative position (displacement) in the X direction with respect to the eye under examination E, and the displacement in the Z direction corresponds to the relative position (displacement) in the Z direction with respect to the eye under examination E.

[0208] Regarding the displacement in the Y direction (relative position, displacement), since there is no influence of the inclination of the second imaging systems 3BL and 3BR with respect to the second illumination system 2B, it can be calculated based on the magnification (optical magnification) of the second imaging systems 3BL and 3BR.

[0209] In this operation example, the data processing unit 8 obtains the three-dimensional relative position composed of the relative position in the X direction, the relative position in the Y direction, and the relative position in the Z direction in the above manner. The control unit 7 controls the movement mechanism 6 so as to cancel the obtained three-dimensional relative position, thereby moving the optical head in the X direction, the Y direction, and the Z direction (S22). Thereby, the precise alignment is completed.

[0210] Next, several examples of the tracking in step S3 will be described. Further referring to FIG. 7 below, the tracking in this operation example is executed using a shine-proof image generated as a moving image by the second illumination system 2B and the second imaging systems 3BL and 3BR, similar to the fine alignment. The tracking in this operation example is performed to maintain a suitable positional relationship between the eye E to be examined and the optical head achieved by the rough alignment and the fine alignment in step S2.

[0211] When a new shine-proof image is acquired (S31), the data processing unit 8 detects a Purkinje image from this shine-proof image (S32) and evaluates the deviation of the Purkinje image with respect to a predetermined target position (S33). This target position may be, for example, the position of the Purkinje image when the fine alignment is completed or a position in the vicinity thereof, or the center of the frame of the shine-proof image. The evaluation of the deviation in step S33 may be, for example, a comparison with a preset threshold value.

[0212] If the deviation of the Purkinje image with respect to the target position exceeds the threshold value (S34: No), the process proceeds to step S35. If the deviation of the Purkinje image with respect to the target position is below the threshold value (S34: Yes), the process proceeds to step S37.

[0213] The data processing unit 8 has a timing function. When the deviation exceeds the threshold value (S34: No), the data processing unit 8 determines whether the length of the time during which the deviation exceeds the threshold value has reached a predetermined time (S35).

[0214] If the length of the time during which the deviation exceeds the threshold value has not reached the predetermined time (S35: No), the process returns to step S31.

[0215] When the length of time during which the deviation exceeds the threshold reaches a predetermined time (S35: Yes), the process proceeds to step S36. The control unit 7 controls the moving mechanism 6 based on the latest deviation obtained in step S33, and moves the optical head so as to cancel the deviation (S36). After the movement of the optical head, the process returns to step S31.

[0216] The processing steps described above are repeated until it is determined as "Yes" in step S34. In step S34, when the data processing unit 8 determines that the deviation of the Purkinje image with respect to the target position is equal to or less than the threshold (S34: Yes), the process proceeds to step S37.

[0217] In step S37, a final determination is made as to whether or not to perform imaging (anterior eye segment scan) (S37). This final determination may be, for example, an instruction operation using the user interface 10. If imaging is not started (S37: No), the process returns to step S31. If imaging is started (S37: Yes), the process proceeds to step S4, and an anterior eye segment scan is applied to the eye to be examined E (S4).

[0218] In this operation example, the final determination step (S37) for starting imaging is performed, but the embodiment is not limited to this. For example, the ophthalmic device 1 may be configured to perform an anterior eye segment scan (S4) in response to determining that the deviation of the Purkinje image with respect to the target position is equal to or less than the threshold (S34: Yes). Such a function is called auto shoot. This concludes the description of this operation example.

[0219] Subsequently, some modified examples of the ophthalmic device 1 will be described.

[0220] A first modified example will be described. The processing example shown in FIG. 13 is executed in step S2 (auto alignment) of FIG. 5. This processing example is executed instead of the processing example of FIG. 6. In this processing example, step S23 is executed between step S19 and step S20 of the processing example of FIG. 6.

[0221] When the projection of infrared coaxial light onto the eye E to be examined is started in step S19, a Purkinje image is formed at a position behind the corneal apex of the eye E to be examined. In this processing example, the frontal image whose acquisition was started in step S12 is referred to. The data processing unit 8 analyzes the frontal image to detect the Purkinje image, and calculates the deviation of the Purkinje image with respect to a predetermined reference position (for example, the center of the frame) of the frame of the frontal image. The calculated deviation is the deviation in the XY directions. The control unit 7 controls the moving mechanism 6 so as to cancel the calculated XY deviation, thereby arranging the optical head (particularly, the second illumination system 2B and the second imaging systems 3BL and 3BR) at a suitable XY position for anterior eye segment scanning (S23: XY alignment). After the XY alignment is performed, the generation of the shine-proof image is started (S20), and the same precise alignment as in FIG. 6 is executed (S21, S22).

[0222] In this processing example, after the rough alignment, as a preparation for starting the precise alignment, an XY alignment combining the Purkinje image and the frontal image is executed. Thereby, the possibility that the Purkinje image is depicted in the shine-proof image obtained by the second illumination system 2B and the second imaging system 3B can be further improved.

[0223] Next, a second modification will be described. As described above, the Purkinje image is formed at a position separated from the corneal apex by a distance of half of the corneal radius of curvature in the Z direction. That is, the position of the observed Purkinje image depends on the corneal radius of curvature. Therefore, in a corneal deformed eye such as a keratoconus eye, a post-LASIK eye, or an orthokeratology-treated eye, the position of the observed Purkinje image will be different from that in a standard eye. Therefore, when applying the precise alignment using the Purkinje image to a corneal deformed eye, it is considered desirable to take this fact into account.

[0224] The processing example of FIG. 14 is executed between the precise alignment of FIG. 6 (or FIG. 13; the same applies hereinafter) and the tracking of FIG. 5. This processing example readjusts the Z position, which is greatly affected by corneal deformation, among the alignment states (XYZ positions) achieved by the precise alignment of FIG. 6. In addition to this readjustment of the Z position, readjustment of the XY positions may also be executed.

[0225] In this processing example, for example, the information of the eye to be examined input in step S1 may include information indicating that the shape of the cornea Co of the eye to be examined E is not standard. Examples of this information include information indicating that it is a corneal deformed eye, the value of corneal curvature, the value of the corneal radius of curvature, the name of the disease, the name of the treatment, and the like. When electronic medical record information or the like is input in step S1, the data processing unit 8 may search for information regarding the corneal shape from the input electronic medical record information or the like, and determine whether the shape of the cornea Co of the eye to be examined E is standard based on the searched information.

[0226] In this processing example, when the shape of the cornea Co of the eye to be examined E is not standard, after performing the processing of FIG. 14 after step S22, the process may proceed to step S3, and when the shape of the cornea Co of the eye to be examined E is standard, the process may proceed from step S22 to step S3 without performing the processing of FIG. 14.

[0227] Now, referring further to FIG. 15, the processing example of FIG. 14 will be described. In the processing example of FIG. 14, first, the ophthalmic apparatus 1 acquires a new shine-proof image G by the second illumination system 2B and the second imaging systems 3BL and 3BR, in the same manner as the precise alignment performed until immediately before (S41).

[0228] The shine-proof image G acquired in this step may be a pair of shine-proof images acquired by the second imaging systems 3BL and 3BR, or may be a shine-proof image acquired by one of the second imaging systems 3BL and 3BR.

[0229] Next, the data processing unit 8 applies segmentation to the Shine-proof image G acquired in step S41 to detect an image area (corneal front image CoA) corresponding to the front (surface) of the cornea Co of the eye E to be examined (S42), and specifies the corneal vertex position CA based on the detected corneal front image CoA (S43).

[0230] Reference numerals CoP, CrA, and CrP in FIG. 15 indicate a corneal back surface image, a lens front surface image, and a lens back surface image, respectively.

[0231] Further, the data processing unit 8 detects the Purkinje image Pu drawn in the Shine-proof image G acquired in step S41 (S44).

[0232] The process of step S44 may be executed before the processes of steps S42 and S43, or at least a part of the processes of steps S42 and S43 and at least a part of the process of step S44 may be executed in parallel.

[0233] Next, the data processing unit 8 calculates the distance d(CA, Pu) between the corneal vertex position CA specified in step S43 and the Purkinje image Pu detected in step S44 (S45).

[0234] Instead of the corneal vertex-Purkinje image distance d(CA, Pu), for example, the corneal vertex-lens front surface distance d(CA, CrA), the corneal vertex-lens back surface distance d(CA, CrP), the distance between the corneal vertex position CA and the center of the lens, etc. may be calculated.

[0235] The ophthalmic device 1 performs final Z alignment based on the corneal vertex-Purkinje image distance d(CA, Pu) calculated in step S46). Thereby, even when the eye E to be examined is a corneal deformed eye, auto-alignment can be suitably performed.

[0236] In one example of step S46, the data processing unit 8 specifies a position 4 millimeters away from the corneal apex position on the line segment connecting the corneal apex position CA and the Purkinje image Pu based on the position of the Purkinje image in a standard eye (a position about 4 millimeters away from the corneal apex position) and the distance d(CA, Pu) between the corneal apex and the Purkinje image. The control unit 7 performs the final Z alignment targeting the specified position.

[0237] In another example of step S46, the data processing unit 8 evaluates the value of the distance d(CA, Pu) between the corneal apex and the Purkinje image of the eye to be examined E. For example, it determines whether the distance d(CA, Pu) between the corneal apex and the Purkinje image of the eye to be examined E is included in a preset allowable range based on the standard value (about 4 millimeters) of the distance between the corneal apex and the Purkinje image. When the distance d(CA, Pu) between the corneal apex and the Purkinje image is included in the allowable range, the data processing unit 8 controls to shift to step S3 without performing the final Z alignment. When the distance d(CA, Pu) between the corneal apex and the Purkinje image is not included in the allowable range, the data processing unit 8 determines the target position in the Z direction based on the difference between the distance d(CA, Pu) between the corneal apex and the Purkinje image and the standard value (or the allowable range). The control unit 7 executes the final Z alignment based on the determined target position.

[0238] In this processing example, when the eye to be examined E is a corneal deformed eye, in addition to the rough alignment and the precise alignment, the final Z alignment is performed. On the other hand, when the eye to be examined E is a corneal deformed eye, the data processing unit 8 can correct the target position in the Z direction in the precise alignment based on the corneal shape information of the eye to be examined E (for example, corneal curvature, corneal radius of curvature, degree of corneal deformation, etc.). According to this example, even when the eye to be examined E is a corneal deformed eye, it is possible to suitably perform the auto alignment. Furthermore, there is also an advantage that it is not necessary to perform the final Z alignment in addition to the rough alignment and the precise alignment.

[0239] Next, a third modification will be described. In the above aspect, precise alignment is performed by a pair of second imaging systems 3BL and 3BR (a combination of a left imaging optical system 30L and a right imaging optical system 30R), but the pair of second imaging systems that can be used for precise alignment is not limited to this combination.

[0240] For example, using a combination of the first imaging system 3A and the second imaging system 3BL, precise alignment similar to the above aspect can be performed. Also, using a combination of the first imaging system 3A and the second imaging system 3BR, precise alignment can be performed in the same manner as the above aspect.

[0241] Although a Purkinje image was detected from the first shine-proof image among the pair of shine-proof images generated by the pair of second imaging systems 3BL and 3BR, when no Purkinje image was detected from the second shine-proof image, the ophthalmic apparatus 1 can detect a Purkinje image from the frontal image generated by the first imaging system 3A. Further, the ophthalmic apparatus 1 can perform precise alignment in the same manner as the above aspect based on the Purkinje image detected from the frontal image and the Purkinje image detected from the second shine-proof image.

[0242] As described above, some non-limiting aspects of the ophthalmic apparatus according to the embodiment have been described. It is possible to at least partially combine any two or more aspects.

[0243] Embodiments according to the present disclosure are not limited to ophthalmic devices. As embodiments other than ophthalmic devices, there are a method of controlling an ophthalmic device, a method of photographing the anterior eye, a program, a recording medium, and the like. The recording medium is a computer-readable non-transitory recording medium. The form of the recording medium may be arbitrary, and for example, it may be any of a magnetic disk, an optical disk, a magneto-optical disk, and a semiconductor memory. Similar to the embodiments of the ophthalmic device, these embodiments can also provide a novel alignment method applicable to an ophthalmic device that performs an anterior eye scan using slit light. Any matter described in the present disclosure can be combined with the method according to the embodiment.

[0244] The embodiments and aspects described in the present disclosure are merely illustrative. Any modification (omission, substitution, addition, etc.) within the scope of the gist of the present invention can be applied to the embodiments and aspects of the present disclosure.

Explanation of Reference Numerals

[0245] 1 Ophthalmic device 2 Lighting unit 2A First lighting system 2B Second lighting system 3 Photographing unit 3A First photographing system 3B, 3BL, 3BR Second photographing system 6 Moving mechanism 7 Control unit 8 Data processing unit

Claims

1. An illumination unit including a first illumination system that projects first illumination light onto the anterior eye part of the eye to be examined, and a second illumination system that projects second illumination light onto the anterior eye part from the front; An imaging unit including a first imaging system that images the anterior eye part from the front, and a pair of second imaging systems that image the anterior eye part obliquely and from different directions; A moving mechanism that moves the illumination unit and the imaging unit; A processor and including wherein each of the second illumination system and the pair of second imaging systems is configured as a shine-proof optical system that satisfies the shine-proof condition; The processor executes a first alignment process including a process of analyzing a first anterior eye part image obtained by imaging the anterior eye part onto which the first illumination light is projected with the first imaging system to obtain a first relative position of the illumination unit and the imaging unit with respect to the eye to be examined, and a process of controlling the moving mechanism based on the first relative position; After the first alignment process, a second alignment process including a process of analyzing a pair of second anterior eye part images obtained by imaging the anterior eye part onto which the second illumination light is projected with the pair of second imaging systems to obtain a second relative position of the illumination unit and the imaging unit with respect to the eye to be examined, and a process of controlling the moving mechanism based on the second relative position is executed; After the second alignment, a imaging process is executed by combining a process of controlling the second illumination system to project slit light onto the anterior eye part from the front, a process of controlling the pair of second imaging systems to generate a time-series image of the anterior eye part onto which the slit light is projected, and a process of controlling the moving mechanism to move the illumination unit and the imaging unit in the width direction of the slit light. An ophthalmic apparatus.

2. The processor executes the first alignment process so that a Purkinje image due to corneal reflection of the second illumination light is drawn in each of a pair of second anterior eye part images obtained by the pair of second imaging systems; In the second alignment process, each of the pair of second anterior eye part images is analyzed to detect a pair of Purkinje images, and the second relative position is obtained based on the pair of Purkinje images. The ophthalmic apparatus according to Claim 1.

3. In the second alignment process, the processor obtains the three-dimensional relative positions of the illumination unit and the imaging unit with respect to the eye to be examined based on the coordinates of the pair of Purkinje images in the pair of second anterior eye images, and controls the movement mechanism based on the second relative position including the three-dimensional relative positions. The ophthalmic apparatus according to claim 2.

4. The pair of second imaging systems are arranged to be inclined by symmetrical angles with respect to the width direction of the slit light with respect to the projection direction of the slit light onto the anterior eye. In the second alignment process, the processor obtains the three-dimensional relative positions based on the coordinates of the pair of Purkinje images and reference information created in advance. The ophthalmic apparatus according to claim 3.

5. The reference information records the relationship between the coordinates in the width direction in the images generated by the pair of second imaging systems and the displacements of the pair of second imaging systems in the width direction and the projection direction with respect to a predetermined reference position. In the second alignment process, the processor obtains the relative position in the width direction and the relative position in the projection direction by obtaining the displacements corresponding to the coordinates of the pair of Purkinje images in the pair of second anterior eye images based on the reference information. The ophthalmic apparatus according to claim 4.

6. In the second alignment process, the processor obtains the relative position in the direction perpendicular to both the projection direction of the slit light and the width direction of the slit light based on the magnifications of the pair of second imaging systems. The ophthalmic apparatus according to claim 3.

7. In the first alignment process, the processor analyzes the first anterior eye image to calculate the focus degree for a predetermined region of the anterior eye, obtains the relative position in the projection direction of the slit light with respect to the anterior eye based on the focus degree, and controls the movement mechanism based on the first relative position including the relative position in the projection direction. The ophthalmic apparatus according to any one of claims 1 to 6.

8. In the first alignment process, the processor executes a combined process of a process of calculating the focus degree and a process of moving the illumination unit and the imaging unit in the projection direction by controlling the movement mechanism in order to determine the target movement positions of the illumination unit and the imaging unit in the projection direction of the slit light. The ophthalmic apparatus according to claim 7.

9. In the first alignment process, the processor determines the movement target position by searching, through the combination process, for the position in the projection direction at which the variance value obtained by applying a Laplacian filter to the first anterior eye image is maximized. The ophthalmic apparatus according to claim 8.

10. In the first alignment process, the processor uses, as the focus level, the variance value obtained by applying a Laplacian filter to the first anterior eye image. The ophthalmic apparatus according to claim 7.

11. In the first alignment process, the processor analyzes the first anterior eye image to identify the image position corresponding to a predetermined feature position of the anterior eye, determines the relative position in the two-dimensional direction perpendicular to the projection direction of the slit light with respect to the anterior eye based on the image position, and controls the movement mechanism based on the first relative position including the relative position in the two-dimensional direction. The ophthalmic apparatus according to any one of claims 1 to 6.

12. In the first alignment process, the processor analyzes the first anterior eye image to identify the image position corresponding to a predetermined feature position of the anterior eye, determines the relative position in the two-dimensional direction perpendicular to the projection direction of the slit light with respect to the anterior eye based on the image position, controls the movement mechanism based on the relative position in the two-dimensional direction, after controlling the movement mechanism based on the relative position in the two-dimensional direction, analyzes the first anterior eye image to calculate the focus level for a predetermined region of the anterior eye, determines the relative position in the projection direction based on the focus level, and controls the movement mechanism based on the relative position in the projection direction. The ophthalmic apparatus according to any one of claims 1 to 6.

13. In the second alignment process, the processor causes the first imaging system to acquire a third anterior eye image in parallel with the acquisition of the pair of second anterior eye images by the pair of second imaging systems, when a Purkinje image is not detected from one of the pair of second anterior eye images acquired by the pair of second imaging systems, analyzes the other second anterior eye image and the third anterior eye image to determine the second relative position. The ophthalmic apparatus according to claim 2.

14. An illumination unit including a first illumination system that projects first illumination light onto the anterior eye of the eye to be examined and a second illumination system that projects second illumination light onto the anterior eye from the front. An imaging unit including a first imaging system for imaging the anterior eye segment of the subject eye from the front and a second imaging system for imaging the anterior eye segment of the subject eye obliquely; A moving mechanism for moving the illumination unit and the imaging unit; A processor and including: The second illumination system and the second imaging system are configured as a shine-proof optical system that satisfies the shine-proof conditions; The processor executes a first alignment process including a process of analyzing an anterior eye segment image obtained by imaging the anterior eye segment onto which the first illumination light is projected with the first imaging system to obtain a first relative position of the illumination unit and the imaging unit with respect to the subject eye, and a process of controlling the moving mechanism based on the first relative position; After the first alignment process, a pair of anterior eye segment images obtained by imaging the anterior eye segment onto which the second illumination light is projected with the first imaging system and the second imaging system are analyzed to obtain a second relative position of the illumination unit and the imaging unit with respect to the subject eye, and a second alignment process including a process of controlling the moving mechanism based on the second relative position is executed; After the second alignment, a process of controlling the second illumination system to project slit light onto the anterior eye segment from the front, a process of controlling the second imaging system to generate a time-series image of the anterior eye segment onto which the slit light is projected, and a process of controlling the moving mechanism to move the illumination unit and the imaging unit in the width direction of the slit light are combined to execute an imaging process; An ophthalmic apparatus.

15. A method for controlling an ophthalmic apparatus for imaging the anterior eye segment of a subject eye, wherein the ophthalmic apparatus includes an illumination unit including a first illumination system for projecting first illumination light onto the anterior eye segment of the subject eye and a second illumination system for projecting second illumination light onto the anterior eye segment from the front, an imaging unit including a first imaging system for imaging the anterior eye segment from the front and a pair of second imaging systems for imaging the anterior eye segment obliquely and from different directions, a moving mechanism for moving the illumination unit and the imaging unit, a processor and including: Each of the second illumination system and the pair of second imaging systems is configured as a shine-proof optical system that satisfies the shine-proof conditions; The first illumination system is controlled to project the first illumination light onto the anterior eye segment, and the first imaging system is controlled to obtain a first anterior eye segment image; Cause the processor to execute a first alignment process including a process of analyzing the first anterior eye image to obtain a first relative position of the illumination unit and the imaging unit with respect to the eye to be examined, and a process of controlling the movement mechanism based on the first relative position. After the first alignment process, control the second illumination system to project the second illumination light onto the anterior eye part, and control the pair of second imaging systems to obtain a pair of second anterior eye images. Cause the processor to execute a second alignment process including a process of analyzing the pair of second anterior eye images to obtain a second relative position of the illumination unit and the imaging unit with respect to the eye to be examined, and a process of controlling the movement mechanism based on the second relative position. After the second alignment, cause the processor to execute an imaging process combining a process of controlling the second illumination system to project slit light onto the anterior eye part from the front, a process of controlling the pair of second imaging systems to generate a time-series image of the anterior eye part onto which the slit light is projected, and a process of controlling the movement mechanism to move the illumination unit and the imaging unit in the width direction of the slit light. Method.

16. A method for controlling an ophthalmic device for photographing the anterior eye part of an eye to be examined, wherein the ophthalmic device includes an illumination unit including a first illumination system that projects first illumination light onto the anterior eye part of the eye to be examined and a second illumination system that projects second illumination light onto the anterior eye part from the front, an imaging unit including a first imaging system that photographs the anterior eye part from the front and a second imaging system that photographs the anterior eye part obliquely, a movement mechanism that moves the illumination unit and the imaging unit, and a processor and the second illumination system and the second imaging system are configured as a shine-proof optical system that satisfies the shine-proof conditions. Control the first illumination system to project the first illumination light onto the anterior eye part, and control the first imaging system to obtain an anterior eye image. Cause the processor to execute a first alignment process including a process of analyzing the anterior eye image to obtain a first relative position of the illumination unit and the imaging unit with respect to the eye to be examined, and a process of controlling the movement mechanism based on the first relative position. After the first alignment process, control the second illumination system to project the second illumination light onto the anterior eye part, and control the first imaging system and the second imaging system to obtain a pair of anterior eye images. cause the processor to execute a second alignment process including a process of analyzing the pair of anterior eye images to obtain a second relative position of the illumination unit and the imaging unit with respect to the eye to be examined, and a process of controlling the movement mechanism based on the second relative position; after the second alignment, cause the processor to execute an imaging process combining a process of controlling the second illumination system to project slit light onto the anterior eye from the front, a process of controlling the second imaging system to generate a time-series image of the anterior eye onto which the slit light is projected, and a process of controlling the movement mechanism to move the illumination unit and the imaging unit in the width direction of the slit light; Method. **Claim 17** A program for causing a computer to execute the method according to claim 15 or 16. **Claim 18** A computer-readable non-transitory recording medium on which the program according to claim 17 is recorded.

Images