Ophthalmic device, method for controlling ophthalmic device, and recording medium

Abstract

An ophthalmic device according to an exemplary embodiment includes a Scheimpflug imaging system and an illumination system. The Scheimpflug imaging system is configured so as to satisfy the Scheimpflug condition, and generates data by imaging the anterior segment of an eye to be examined. This Scheimpflug imaging system includes an image sensor. The image sensor is disposed on the image plane of the Scheimpflug imaging system and is disposed eccentrically with respect to the optical axis of the Scheimpflug imaging system. The illumination system projects illumination light onto the object plane of the Scheimpflug imaging system.

Description

Ophthalmic device, method for controlling an ophthalmic device, and recording medium

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

[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 device having an imaging function is not limited to these ophthalmic imaging devices, and imaging functions are also installed 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, and are used for examinations and measurements, or for operations such as alignment and focusing.

[0003] Although a slit lamp microscope has been widely used in anterior eye segment observation, other modalities have been proposed in recent years. For example, U.S. Patent No. 6,286,958 (Patent Document 1), U.S. Patent No. 7,425,068 (Patent Document 2), Japanese Unexamined Patent Application Publication No. 2023-49320 (Patent Document 3), and Japanese Unexamined Patent Application Publication No. 2019-213733 (Patent Document 4) disclose an ophthalmic device that uses an optical system configured to satisfy the condition of shine-proof in an imaging system and uses an optical system configured to project illumination light onto the object plane of the shine-proof imaging system in an illumination system.

[0004] The ophthalmic devices disclosed in Patent Documents 1 and 2 are configured to collect a plurality of images of the anterior eye segment by integrally rotating, about an axis substantially coinciding with the optical axis of the subject eye, an illumination system for projecting slit light onto the anterior eye segment and a shine-proof imaging system for digitally imaging the anterior eye segment.

[0005] Furthermore, the ophthalmic apparatus disclosed in Patent Documents 3 and 4 is configured to collect multiple images of the anterior segment of the eye by integrally moving a lighting system for projecting slit light onto the anterior segment of the eye and a shineproof imaging system for digitally imaging the anterior segment of the eye in parallel in the width direction of the slit light.

[0006] Anterior segment imaging modalities using a Scheinproof system have the advantage of being able to collect anterior segment images with a deep depth of field and in focus across the entire object plane. On the other hand, in a Scheinproof system, the image plane is tilted with respect to its optical axis (imaging optical axis), and the optical axis of the image sensor placed on the image plane is also tilted with respect to the imaging optical axis. Unlike cases where there is no tilt (for example, when a Scheinproof system is not used), light enters the image sensor from an oblique direction, which leads to a problem of reduced light detection efficiency by the image sensor.

[0007] One objective of this disclosure is to improve the photodetection efficiency of anterior segment imaging modalities using a Scheinproof imaging system.

[0008] One exemplary embodiment of the invention is an ophthalmic apparatus comprising a Scheinproof imaging system and an illumination system. The Scheinproof imaging system is configured to satisfy Scheinproof conditions and to image the anterior segment of the eye under examination and generate data. The illumination system is configured to project illumination light onto the object surface of the Scheinproof imaging system. The Scheinproof imaging system includes an image sensor. The image sensor is positioned on the image plane of the Scheinproof imaging system and is eccentrically positioned with respect to the optical axis of the Scheinproof imaging system.

[0009] Another exemplary embodiment of the embodiment is a method for controlling an ophthalmic apparatus for photographing the anterior segment of an eye under examination. The ophthalmic apparatus of this embodiment comprises a Scheinproof imaging system, an illumination system, a display unit, and a processor. The Scheinproof imaging system is configured to satisfy Scheinproof conditions and to photograph the anterior segment of an eye under examination and generate data. The illumination system is configured to project illumination light onto the object surface of the Scheinproof imaging system. The Scheinproof imaging system includes an image sensor. The image sensor is positioned on the image plane of the Scheinproof imaging system and is eccentrically positioned with respect to the optical axis of the Scheinproof imaging system. The method of this embodiment includes the step of causing the processor to perform control for displaying an image of the eye under examination on the display unit based on the data generated by the Scheinproof imaging system.

[0010] A further exemplary embodiment of the embodiment is a method for controlling an ophthalmic apparatus for photographing the anterior segment of an eye under examination. The ophthalmic apparatus of this embodiment comprises a Scheinproof imaging system, an illumination system, a moving mechanism, a display unit, and a processor. The Scheinproof imaging system is configured to satisfy Scheinproof conditions and to photograph the anterior segment of an eye under examination and generate data. The illumination system is configured to project illumination light onto the object surface of the Scheinproof imaging system. The moving mechanism is configured to move the Scheinproof imaging system and the illumination system. The Scheinproof imaging system includes an image sensor. The image sensor is positioned on the image plane of the Scheinproof imaging system and is eccentrically positioned with respect to the optical axis of the Scheinproof imaging system. The method according to this embodiment includes the step of causing the processor to control the Scheinproof imaging system, the illumination system, and the moving mechanism to cause the Scheinproof imaging system to generate a dataset corresponding to a plurality of positions. Furthermore, the method according to this embodiment includes the step of causing the processor to control the display unit to display an image of the eye under examination based on this dataset.

[0011] A further exemplary embodiment of the embodiment is a computer-readable non-temporary recording medium on which a program causing a computer to execute the method according to the exemplary embodiment is recorded.

[0012] This is a schematic diagram showing the configuration of an ophthalmic device according to a non-limiting aspect of the embodiment. This is a schematic diagram showing the configuration of an ophthalmic device according to a non-limiting aspect of the embodiment. This is a schematic diagram showing the configuration of an ophthalmic device according to a non-limiting aspect of the embodiment. This is a schematic diagram showing the configuration of an ophthalmic device according to a non-limiting aspect of the embodiment. This is a schematic diagram showing the configuration of an ophthalmic device according to a non-limiting aspect of the embodiment. This is a flowchart for explaining the operation of an ophthalmic device according to a non-limiting aspect of the embodiment. This is a schematic diagram for explaining the operation of an ophthalmic device according to a non-limiting aspect of the embodiment. This is a schematic diagram for explaining the operation of an ophthalmic device according to a non-limiting aspect of the embodiment. This is a schematic diagram for explaining the operation of an ophthalmic device according to a non-limiting aspect of the embodiment. This is a schematic diagram for explaining the operation of an ophthalmic device according to a non-limiting aspect of the embodiment. This is a schematic diagram for explaining the operation of an ophthalmic device according to a non-limiting aspect of the embodiment.

[0013] Non-limiting embodiments relating to this disclosure will be described below.

[0014] Any prior art can be combined with the embodiments. For example, any matter described in the documents cited in this disclosure can be combined with any aspect of the embodiments. Furthermore, at least one of any prior art related to the art of this disclosure, any prior art in a similar art, and any prior art in a different art may be combined with any aspect of the embodiments. In addition, any technical matter disclosed by the applicant of this application with respect to the art related to this disclosure (such as matters disclosed in patent applications, papers, etc.) can be incorporated into this disclosure by reference.

[0015] Two or more of the various non-limiting embodiments of the embodiment can be combined at least partially.

[0016] At least some of the various functions related to this disclosure are implemented using a circuit configuration or a processing circuit configuration. The circuit configuration or processing circuit configuration is configured and / or programmed to perform at least a portion of the disclosed functions, and includes general-purpose processors, dedicated processors, integrated circuits, CPUs (Central Processing Units), GPUs (Graphics Processing Units), ASICs (Application Specific Integrated Circuits), programmable logic devices (e.g., SPLDs (Simple Programmable Logic Devices), CPLDs (Complex Programmable Logic Devices), FPGAs (Field Programmable Gates) This includes any of the following: Array, conventional circuit configurations, and any combination thereof. A processor is considered a processing circuit configuration or circuit configuration, including transistors and / or other circuit configurations. In this disclosure, a circuit configuration, unit, means, or similar terms means hardware that performs at least a portion of the disclosed functions, or hardware programmed to perform at least a portion of the disclosed functions. The hardware may be the hardware disclosed herein, or it may be known hardware programmed and / or configured to perform at least a portion of the described functions. If the hardware is a processor that can be considered a certain type of circuit configuration, then a circuit configuration, unit, means, or similar terms means a combination of hardware and software, the software being used to constitute the hardware and / or processor.

[0017] <Summary of Embodiments> One objective of the embodiments described herein is to improve the photodetection efficiency of anterior segment imaging modality using a Shineproof imaging system. Achieving this objective will result in exceptional effects that cannot be achieved with conventional similar modalities, such as improved imaging quality and improved image quality. Improvement in imaging quality includes, for example, increased freedom in various imaging conditions such as illumination intensity, shutter speed (electronic shutter, mechanical shutter), aperture value, and gain. Furthermore, the freedom in selecting various devices such as light sources will also increase. Improvement in image quality includes, for example, improvements in various qualities such as brightness and contrast. This improvement in image quality is expected to facilitate observation by physicians and improve the quality of various image processing such as analysis and evaluation.

[0018] The purposes and effects of the embodiments relating to this disclosure are not limited to those described above. Several non-limiting embodiments are described below, and those skilled in the art will understand that each embodiment produces effects according to its characteristics (configuration, operation, function, use, etc.).

[0019] A first embodiment of the invention is an ophthalmic apparatus comprising a shineproof imaging system and an illumination system. The shineproof imaging system is configured to satisfy the shineproof conditions and to image the anterior segment of the eye under examination and generate data. The illumination system is configured to project illumination light onto the object surface of the shineproof imaging system. Furthermore, the shineproof imaging system includes an image sensor. The image sensor is positioned on the image plane of the shineproof imaging system and is eccentrically positioned with respect to the optical axis of the shineproof imaging system.

[0020] The Scheinproof condition is a condition relating to the optical system (in this disclosure, the imaging system), specifying that the optical system is configured such that the object plane, the principal lens plane, and the film plane (light detection surface, light receiving surface) intersect on the same straight line. In an optical system that satisfies the Scheinproof condition, the object plane is not arranged parallel to the principal lens plane. A camera using such a Scheinproof optical system (Scheinproof camera) can simultaneously focus and capture images over a wide depth range, from near to far objects. In anterior segment imaging of the disclosure, for example, it is possible to capture images with the entire wide depth range from the anterior surface of the cornea to the posterior surface of the lens in focus. This has the effect of obtaining high-resolution images that represent the entire main observation range of the anterior segment.

[0021] According to the ophthalmic apparatus of the first embodiment, by arranging the image sensor on the image plane to satisfy the shineproof conditions, it is possible to achieve shooting with a deep depth of field, while by eccentrically arranging the image sensor with respect to the optical axis of the shineproof shooting system, it is possible to improve the decrease in light detection efficiency caused by the inclination of the image plane with respect to the optical axis of the shineproof shooting system.

[0022] A second embodiment of the embodiment is an ophthalmic apparatus of the first embodiment, wherein the image sensor of the Scheinproof imaging system includes a microlens array. Furthermore, the image sensor is eccentrically positioned with respect to the optical axis of the Scheinproof imaging system such that the angle between the light rays guided to the microlens array by the Scheinproof imaging system and the optical axis of the microlens array is smaller than when it is concentric with respect to the optical axis of the Scheinproof imaging system.

[0023] According to the ophthalmic apparatus of the second embodiment, the image sensor is eccentrically positioned with respect to the optical axis of the Scheinproof imaging system such that the angle between the light rays guided to the microlens array and the optical axis of the microlens array is smaller than the angle when the image sensor is concentrically positioned with respect to the optical axis of the Scheinproof imaging system. As a result, the image sensor can detect light rays that are incident more parallel to the optical axis of the microlens array. This makes it possible to achieve better light detection efficiency than in the case of concentric arrangement.

[0024] A third embodiment of the embodiment is an ophthalmic apparatus according to the first or second embodiment, wherein the image sensor of the Scheinproof imaging system includes a photodetector array and a microlens array. The microlens array is configured as an imaging lens group for the photodetector array. Furthermore, the image sensor is eccentrically positioned with respect to the optical axis of the Scheinproof imaging system such that the angle between the light rays guided to the photodetector array by the Scheinproof imaging system and the optical axis of the microlens array is smaller than when the sensors are concentric with respect to the optical axis of the Scheinproof imaging system.

[0025] According to the ophthalmic apparatus of the third embodiment, the image sensor is eccentrically positioned with respect to the optical axis of the Shineproof imaging system such that the angle between the light ray guided to the photodetector element array and the optical axis of the microlens array is smaller than the angle when the image sensor is concentrically positioned with respect to the optical axis of the Shineproof imaging system. As a result, the photodetector element array can detect light rays that are incident more parallel to the optical axis of the microlens array. This makes it possible to achieve better photodetection efficiency than in the case of concentric arrangement.

[0026] A fourth embodiment is an ophthalmic apparatus according to any of the first to third embodiments, wherein the center position of the light detection surface of the image sensor is located away from the intersection point of the optical axis of the Shineproof imaging system and the image plane.

[0027] According to the ophthalmic device of the fourth embodiment, the decrease in light detection efficiency that occurs in a configuration where the light detection surface and the optical axis of the image sensor intersect at the center of the light detection surface (concentric arrangement) can be improved by eccentrically arranging the image sensor such that the center of the light detection surface is positioned at a location offset from the intersection point.

[0028] A fifth embodiment is the ophthalmic apparatus of the fourth embodiment, wherein the distance between the center position of the light detection surface of the image sensor and the intersection point of the optical axis of the Scheinproof imaging system and the image plane is determined based on at least one of the following: the direction of the light rays guided to the image sensor by the Scheinproof imaging system, the position of the entrance pupil of the Scheinproof imaging system, the diameter of the entrance pupil, and the resolution.

[0029] Here, the direction of light rays directed to the image sensor may be the direction of light rays directed to the image sensor itself, or the direction of light rays directed to a specific element of the image sensor. For example, if the image sensor includes an imaging lens (e.g., a microlens array), the direction of light rays directed to the imaging lens may be considered. Also, if the image sensor includes a photodetector (e.g., a photodetector array), the direction of light rays directed to the photodetector may be considered. Furthermore, if the image sensor includes another element (e.g., a color filter array), the direction of light rays directed to that element may be considered.

[0030] According to the ophthalmic apparatus of the fifth embodiment, the eccentricity (offset amount) of the image sensor can be determined based on the configuration of the shineproof imaging system and the quality of the obtained image. This makes it possible to achieve a desirable light detection efficiency.

[0031] A sixth embodiment is an ophthalmic apparatus according to the fifth embodiment, wherein the distance between the center position of the light detection surface of the image sensor and the intersection point of the optical axis of the Scheinproof imaging system and the image plane is determined such that the angle between the light ray guided to the image sensor by the Scheinproof imaging system and the optical axis of the image sensor is 30 degrees or less, preferably 10 degrees or less.

[0032] Here, the optical axis of the image sensor may be an optical axis defined based on a specific element of the image sensor. For example, if the image sensor includes an imaging lens (e.g., a microlens array), the optical axis of the image sensor may be the optical axis of the imaging lens. Also, if the image sensor includes a photodetector (e.g., a photodetector array), the optical axis of the image sensor may be an optical axis defined based on the photodetector (e.g., a perpendicular line to the photodetector at the center position of the photodetector formed by the photodetector array). Furthermore, if the image sensor includes another element (e.g., a color filter array), the optical axis of the image sensor may be an optical axis defined based on that element.

[0033] According to the ophthalmic apparatus of the sixth embodiment, the angle between the light rays guided to the image sensor by the shineproof imaging system and the optical axis of the image sensor can be reduced (to 30 degrees or less, preferably 10 degrees or less), making it possible for the image sensor to detect light rays incident from an angle nearly parallel to the optical axis of the image sensor. This makes it possible to achieve good light detection efficiency.

[0034] A seventh embodiment is an ophthalmic apparatus according to any of the first to sixth embodiments, comprising a moving mechanism and a first control unit. The moving mechanism is configured to move the shineproof imaging system and the illumination system. The first control unit is configured to cause the shineproof imaging system to generate a dataset corresponding to a plurality of positions by controlling the shineproof imaging system, the illumination system, and the moving mechanism.

[0035] Here, the mode in which the moving mechanism moves the Scheinproof imaging system and the illumination system may be arbitrary. For example, this mode of movement may be either translational movement or rotational movement, or both. Examples of non-limiting translational movement include the modes described in Patent Documents 3 and 4, and examples of non-limiting rotational movement include the modes described in Patent Documents 1 and 2. In the seventh embodiment, the dataset generated by the Scheinproof imaging system includes multiple data points corresponding to multiple positions according to the movement trajectory of the Scheinproof imaging system and the illumination system. Furthermore, the mode of movement may be a single translational movement in one direction, or multiple translational movements in one direction or both directions (reciprocating direction). Alternatively, the mode of movement may be a single rotational movement or multiple rotational movements.

[0036] According to the ophthalmic apparatus of the seventh embodiment, multiple images can be taken while moving the object surface illuminated by the illumination light, making it possible to image a wide area (three-dimensional region) of the anterior segment of the eye with a deep depth of field and good light detection efficiency.

[0037] An eighth embodiment is an ophthalmic apparatus according to any of the first to seventh embodiments, comprising a first shineproof imaging system, a first illumination system, a second shineproof imaging system, and a second illumination system. The first shineproof imaging system is configured to satisfy shineproof conditions and to image the anterior segment of the eye under examination to generate first data. The first illumination system is configured to project first illumination light onto the surface of the first shineproof imaging system. The second shineproof imaging system is configured to satisfy shineproof conditions and to image the anterior segment to generate second data. The second illumination system is configured to project second illumination light onto the surface of the second shineproof imaging system.

[0038] According to the ophthalmic apparatus of the eighth embodiment, since there are two (or more) pairs of shineproof imaging systems and illumination systems, separate imaging with different conditions (e.g., illumination wavelength, illumination intensity, imaging direction, detection wavelength, filter, etc.) can be performed simultaneously, and separate imaging with different conditions can be performed sequentially smoothly. Here, the separate imaging may target the same part of the anterior segment of the eye, or it may target different parts. In the former case, the optical system of the ophthalmic apparatus is designed such that the object surface of the first shineproof imaging system and the object surface of the second shineproof imaging system are at least partially identical. In the latter case, the optical system of the ophthalmic apparatus is designed such that the object surface of the first shineproof imaging system and the object surface of the second shineproof imaging system are at least partially different.

[0039] A ninth embodiment is an ophthalmic apparatus according to any of the first to eighth embodiments, further comprising a fixation optical system. The fixation optical system is configured to present a fixation target to the eye under examination.

[0040] According to the ophthalmic device of the ninth embodiment, the patient can be prompted to keep the eye under examination still during imaging. When scanning the anterior segment as in the seventh embodiment, or when taking separate images sequentially as in the eighth embodiment, the imaging time becomes relatively long, and the possibility of the eye under examination moving becomes relatively high, so the usefulness of the ninth embodiment is considered to be particularly high.

[0041] A tenth embodiment is an ophthalmic apparatus according to any of the first to ninth embodiments, further comprising a second control unit. The second control unit is configured to display an image of the eye under examination on a display device based on data generated by a shineproof imaging system. The display device may be an element of the ophthalmic apparatus according to the tenth embodiment, or it may be an external device (peripheral device).

[0042] According to the ophthalmic apparatus of the tenth embodiment, high-quality images of the anterior segment of the eye, captured with a deep depth of field and good light detection efficiency, can be provided to the user. This allows the user to easily observe the details of the anterior segment. Therefore, the tenth embodiment contributes to improving the quality and efficiency of examinations and diagnoses.

[0043] The eleventh aspect of the embodiment is an ophthalmic device according to any one of the first to tenth aspects, further including a processing unit. The processing unit is configured to execute processing of data generated by the shine-proof imaging system and / or processing of an image based on this data.

[0044] According to the ophthalmic device according to the eleventh aspect, processing such as analysis and evaluation can be performed using high-quality data and high-quality images generated by imaging with a deep depth of field and good light detection efficiency. Therefore, the eleventh aspect contributes to improving the quality and efficiency of diagnosis and examination.

[0045] Any two or more matters related to the first to eleventh aspects can be at least partially combined. Also, any matter described in the present disclosure can be at least partially combined with the first to eleventh aspects. The ophthalmic device 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.

[0046] The twelfth aspect of the embodiment provides a non-limiting method for controlling an ophthalmic device for imaging the anterior segment of an eye to be examined. The ophthalmic device controlled by the method of this aspect includes a shine-proof imaging system, an illumination system, a display unit, and a processor. The shine-proof imaging system is configured to satisfy the conditions of shine-proof and is configured to image the anterior segment of the eye to be examined and generate data. Also, the shine-proof imaging system includes an image sensor. The image sensor is disposed on the image plane of the shine-proof imaging system and is eccentrically disposed with respect to the optical axis of the shine-proof imaging system. The illumination system is configured to project illumination light onto the object plane of the shine-proof imaging system.

[0047] The method of this aspect includes a step of causing the processor to execute control for displaying an image of the eye to be examined based on the data generated by the shine-proof imaging system on the display unit.

[0048] The method according to the 12th aspect has the same effects as the ophthalmic device according to the 1st and 10th aspects.

[0049] The 13th aspect of the embodiment provides a non-limiting method for controlling an ophthalmic device for imaging the anterior segment of an eye to be examined. The ophthalmic device controlled by the method of this aspect includes a shine-proof imaging system, an illumination system, a moving mechanism, a display unit, and a processor. The shine-proof imaging system is configured to satisfy the conditions of shine-proof and is configured to image the anterior segment of the eye to be examined and generate data. The shine-proof imaging system also includes an image sensor. The image sensor is disposed on the image plane of the shine-proof imaging system and is eccentrically disposed with respect to the optical axis of the shine-proof imaging system. The illumination system is configured to project illumination light onto the object plane of the shine-proof imaging system.

[0050] The method of this aspect includes a step of causing the processor to execute control of the shine-proof imaging system, the illumination system, and the moving mechanism for generating a dataset corresponding to a plurality of positions in the shine-proof imaging system. Further, the method of this aspect includes a step of causing the processor to execute control for displaying an image of the eye to be examined based on the generated dataset on the display unit.

[0051] The method according to the 13th aspect has the same effects as the ophthalmic devices according to the 1st, 7th, and 10th aspects.

[0052] Any matter regarding the 1st to 11th aspects can be at least partially combined with the method according to the 12th or 13th aspect. Also, any matter described in the present disclosure can be at least partially combined with the method according to the 12th or 13th aspect. The method according to 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.

[0053] The 14th aspect of the embodiment is a program for causing a computer to execute the method of the 12th or 13th aspect. The computer of the 14th aspect includes the processor of the 12th or 13th aspect.

[0054] The program according to the 14th embodiment produces the same effects as the ophthalmic apparatus according to the first and 10th embodiments, or the same effects as the ophthalmic apparatus according to the first, 7th, and 10th embodiments.

[0055] Any aspect relating to the first to eleventh aspects can be combined at least partially with the program relating to the fourteenth aspect. Furthermore, any aspect described in this disclosure can be combined at least partially with the program relating to the fourteenth aspect. The program relating to such an aspect will produce the effects based on each of the combined aspects, as well as the synergistic effects of two or more of the combined aspects.

[0056] A fifteenth aspect of the embodiment is a computer-readable non-temporary recording medium on which the program of the fourteenth aspect is recorded.

[0057] The recording medium according to the 15th embodiment provides the same effects as the ophthalmic apparatus according to the first and 10th embodiments, or the same effects as the ophthalmic apparatus according to the first, seventh, and 10th embodiments.

[0058] Any aspect relating to the first to eleventh aspects can be combined at least partially with the recording medium relating to the fifteenth aspect. Furthermore, any aspect described in this disclosure can be combined at least partially with the recording medium relating to the fifteenth aspect. A recording medium relating to such a combination will exhibit the effects based on each of the combined aspects, as well as the synergistic effects of two or more of the combined aspects.

[0059] This disclosure describes various non-limiting embodiments, including embodiments 1 through 15. This disclosure primarily describes exemplary embodiments of ophthalmic devices, exemplary embodiments of methods for controlling ophthalmic devices, exemplary embodiments of programs, and exemplary embodiments of recording media. However, those skilled in the art will understand that the categories that may constitute embodiments are not limited to these.

[0060] <Ophthalmic Devices> Several non-limiting embodiments of the ophthalmic devices according to these embodiments will be described.

[0061] Figure 1 shows an example of the configuration of an ophthalmic device according to one embodiment. The ophthalmic device 1 of this embodiment is used for anterior segment imaging of the eye E under examination and includes an illumination imaging optical system 2, a fixation optical system 3, a movement 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 under examination is indicated by the code Co, the iris by the code Ir, and the lens by the code Cr.

[0062] Following the conventions in ophthalmology, the direction along the axis of the eye E under examination (depth direction, length direction) 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 and Z directions (up-down direction, body axis direction) is defined as the Y direction (Y axis).

[0063] Reference numeral 2a indicates the optical axis of the illumination and imaging optical system 2. The optical axis 2a of the illumination and imaging optical system 2 (in this embodiment, the illumination optical axis 21a shown in Figure 2) is arranged substantially parallel to the Z axis. Non-limiting detailed examples of the illumination and imaging optical system 2 will be described later.

[0064] Reference numeral 3a indicates the optical axis of the fixation optical system 3 (referred to as the fixation optical axis). The fixation optical axis 3a is positioned at an angle α with respect to the Z axis (illumination optical axis 21a). This angle α is called the fixation angle. The magnitude of the fixation angle α is non-negative, i.e., zero or positive.

[0065] In the embodiment where a fixation angle α = 0 is applied, the fixation optical system 3 is an optical system arranged coaxially with the illumination and imaging optical system 2, and presents a fixation target coaxial with the light (slit light) projected onto the eye E by the illumination and imaging optical system 2 to the eye E under examination. In this embodiment, the optical path of the Scheinproof optical system and the optical path of the fixation optical system are coaxially coupled by an optical path coupling element. This optical path coupling element may be, for example, a half mirror or a dichroic mirror.

[0066] In the embodiment where a fixation angle α > 0 is applied, the fixation optical system 3 presents the fixation target to the eye E under examination from a direction inclined with respect to the optical axis 2a (Z-axis) of the illumination and imaging optical system 2. This inclination direction may be arbitrarily determined and may be variable.

[0067] The moving mechanism 6 is configured to move the illumination and imaging optical system 2 and the fixation optical system 3. The moving mechanism 6 may be capable of moving the illumination and imaging optical system 2 and the fixation optical system 3 in three dimensions (i.e., in the X, Y, and Z directions). This three-dimensional movement is used for alignment and tracking.

[0068] Furthermore, the moving mechanism 6 can move the illumination and imaging optical system 2 and the fixation optical system 3 to scan the anterior segment of the eye E under examination. When the rotational scanning method for anterior segment scanning described in Patent Documents 1 and 2 is applied to the eye E under examination, the moving mechanism 6 rotates the illumination and imaging optical system 2 around a predetermined axis. When the parallel scanning method for anterior segment scanning described in Patent Documents 3 and 4 is applied to the eye E under examination, the moving mechanism 6 parallel moves the illumination and imaging optical system 2 in a predetermined direction. Non-limiting detailed examples of the moving mechanism 6 will be described later.

[0069] The control unit 7 is configured to control various parts of the ophthalmic device 1. For example, the control unit 7 controls the illumination and imaging optical system 2 (illumination light source, image sensor, optical elements, mechanism, etc.), the fixation optical system 3 (fixation light source, etc.), the movement mechanism 6, the data processing unit 8, the communication unit 9, the user interface 10, and so on.

[0070] The control unit 7 includes a processor, main memory, and auxiliary memory. The auxiliary memory stores various computer programs, such as control programs. These computer programs may be stored in a computer or memory device accessible by the ophthalmic device 1. The functions of the control unit 7 are realized through the cooperation of software, such as control programs, and hardware, such as the processor.

[0071] The data processing unit 8 performs various data processing operations. The data to be processed may be either data acquired by the ophthalmic device 1 or data input from an external source.

[0072] The data processing unit 8 includes a processor, main memory, and auxiliary storage. The auxiliary storage contains computer programs, such as various data processing programs. These computer programs may be stored in a computer or storage device accessible by the ophthalmic device 1. The functions of the data processing unit 8 are realized through the cooperation of software, such as data processing programs, and hardware, such as the processor. Non-specific details of the data processing unit 8 will be described later.

[0073] The communication unit 9 performs data communication between the ophthalmic device 1 and other devices. The method of this data communication can be arbitrarily determined and may be either wired or wireless communication. The transmitted and received data may be encrypted. In this case, the ophthalmic device 1 (for example, the control unit 7 or the data processing unit 8) includes a processor capable of performing encryption and decryption.

[0074] The user interface 10 includes any user interface devices, such as display devices and operating devices. Users such as doctors, patients, and assistants can use the user interface 10 to operate the ophthalmic device 1 and input information to the ophthalmic device 1. At least a part of the user interface 10 may be peripheral devices of the ophthalmic device 1.

[0075] The user interface 10 in this embodiment includes a display unit 11 as shown in Figure 3. The display unit 11 displays various information under the control of the control unit 7. The display unit 11 may include a flat panel display such as a liquid crystal display (LCD). The display unit 11 may also be a touchscreen.

[0076] The user interface 10 may include operating devices (not shown). These operating devices include devices for operating the ophthalmic apparatus 1 and devices for inputting information. For example, operating devices include buttons, switches, levers, dials, handles, knobs, mice, keyboards, trackballs, control panels, etc.

[0077] Some non-limiting detailed examples of the illumination imaging optical system 2 are described below. The illumination imaging optical system 2 includes an imaging system (Scheinproof imaging system) configured to satisfy the conditions of Scheinproof, and an illumination system that illuminates the object surface of this Scheinproof imaging system, and can perform Scheinproof imaging of the anterior segment of the eye E under examination. The illumination imaging optical system 2 is used to apply an anterior segment scan to the eye E under examination and collect a dataset consisting of multiple anterior segment images (anterior segment image set, anterior segment image group).

[0078] The method of anterior segment scanning performed using the illumination imaging optical system 2 may be arbitrary. For example, the method of anterior segment scanning in this embodiment may be a rotational scanning method similar to that in Patent Documents 1 and 2, or a translational scanning method similar to that in Patent Documents 3 and 4. Alternatively, the method of anterior segment scanning in this embodiment may be a combination of the rotational scanning method and the translational scanning method, or a method different from both the rotational scanning method and the translational scanning method (another method), or a combination of at least one of the rotational scanning method and the translational scanning method with an other method.

[0079] The illumination light used for the anterior segment scan in this embodiment may be arbitrary. In the non-limiting embodiments described below, slit light is used as the illumination light. This slit light is generated from light emitted by the illumination light source 13 shown in Figure 3. The illumination light source 13 may be an element of the ophthalmic apparatus 1 (illumination imaging optical system 2, illumination system 21) or an external device connected to the ophthalmic apparatus 1.

[0080] The illumination light source 13 may include, for example, at least one of a visible light source and an infrared light source (near-infrared light source). The visible light source may be a monochromatic visible light source (e.g., a red light source, a green light source, a blue light source, etc.) or a non-monochromatic visible light source. The non-monochromatic visible light source is a light source that outputs visible light with a wavelength band wider than the wavelength band of monochromatic visible light, and may be, for example, a white light source, a broadband visible light source, a wavelength-swept visible light source, etc.

[0081] Figure 2 shows one example of the illumination imaging optical system 2. The optical axis 2a of the illumination imaging optical system 2 shown in Figure 1 corresponds to the illumination optical axis 21a shown in Figure 2. The illumination imaging optical system 2 in this example includes an illumination system 21 and a shineproof imaging system 22.

[0082] Some embodiments may include two or more shineproof imaging systems. For example, as described in Patent Documents 3 and 4, a pair of shineproof imaging systems that perform imaging from opposite directions may be provided. These shineproof imaging systems have a common object surface, and this common object surface is illuminated by an illumination system.

[0083] The illumination system 21 is configured to project illumination light (slit light) onto the anterior segment of the eye E under examination based on the light generated by the illumination light source 13. The slit light is projected onto the object surface of the Scheinproof imaging system 22. The illumination imaging optical system 2 applies Scheinproof imaging to the anterior segment illuminated by the slit light.

[0084] In some embodiments, the illumination system 21 includes an illumination light source 13 that emits light, a slit forming unit that forms a slit opening for converting light from the illumination light source 13 into slit light, and an optical system (such as an objective lens) that projects the slit light generated by the slit forming unit onto the eye E under examination. The illumination system 21 in this example may be configured to allow changes in the dimensions (slit width, slit length) and orientation of the slit opening.

[0085] In some embodiments, the Shineproof imaging system 22 includes an optical system containing various optical elements (e.g., an objective lens, a variable magnification optical system, an imaging lens, a relay lens, etc.) and an image sensor that detects the light guided by this optical system. The image sensor is an area image sensor having a light detection surface (light-receiving surface) formed by a two-dimensionally arranged array of photodetectors, and may be, for example, a CCD image sensor or a CMOS image sensor.

[0086] The angle between the illumination optical axis 21a of the illumination system 21 and the optical axis (photography optical axis) 22a of the Shineproof imaging system 22 is called the Shineproof angle. The magnitude of the Shineproof angle is called the Shineproof angle θ. The Shineproof angle θ can be determined arbitrarily.

[0087] Figure 4 shows a non-limiting configuration example of the illumination system 21 and the shineproof imaging system 22. The illumination system 21 projects slit light 21b onto the eye E under examination. The shineproof imaging system 22 images the anterior segment of the eye E onto which the slit light 21b is projected. The shineproof imaging system 22 includes an image sensor 221. The light detection surface of the image sensor 221 is positioned on the image plane 221P of the shineproof imaging system 22.

[0088] The imaging ray group 22b indicates the field of view (range in the Z direction) of the Scheinproof imaging system 22. In this example, the Scheinproof imaging system 22 is designed so that the field of view includes the area from the anterior surface of the cornea to the posterior surface of the lens.

[0089] Two planes perpendicular to the imaging optical axis 22a are indicated by reference numerals 22P1 and 22P2. The vertical plane 22P1 is positioned to pass through the intersection point C1 of the illumination optical axis 21a and the imaging optical axis 22a. The vertical plane 22P2 is positioned to pass through the intersection point C2 of the imaging optical axis 22a and the image plane 221P.

[0090] In the example shown in Figure 4, the Scheinproof angle formed by the illumination optical axis 21a and the imaging optical axis 22a, and the angle formed by the illumination optical axis 21a and the vertical plane 22P1 are complementary angles. In other words, the sum of the magnitude of the Scheinproof angle and the magnitude of the angle formed by the illumination optical axis 21a and the vertical plane 22P1 is a right angle.

[0091] In some embodiments, the angle between the illumination optical axis 21a and the vertical plane 22P1 may be any value within the range of 0 to 90 degrees. In other words, the Scheinproof angle θ may be any value within the range of 0 to 90 degrees. In this case, for example, it is possible to apply Scheinproof imaging to at least a shallow region of the anterior segment of the eye. In some specific examples, Scheinproof imaging can be applied to a region including at least the cornea and its vicinity.

[0092] Furthermore, in some embodiments, the angle between the illumination optical axis 21a and the vertical plane 22P1 may be any value within the range of 30 to 60 degrees. In other words, the Scheinproof angle θ may be any value within the range of 30 to 60 degrees. In this case, for example, it becomes possible to apply Scheinproof imaging to areas ranging from shallow to slightly deeper regions of the anterior segment of the eye. In some specific examples, Scheinproof imaging can be applied to regions including at least the anterior surface of the cornea and the anterior chamber.

[0093] Furthermore, in some embodiments, the angle between the illumination optical axis 21a and the vertical plane 22P1 may be any value within the range of 35 to 53 degrees. In other words, the Scheinproof angle θ may be any value within the range of 37 to 55 degrees. In this case, for example, it becomes possible to apply Scheinproof imaging to a wide range from the shallow to the deep regions of the anterior segment of the eye. In some specific examples, Scheinproof imaging can be applied to the range from the anterior surface of the cornea to the posterior surface of the lens.

[0094] Here, we have described the case where the Scheinproof angle θ is selected considering the width of the shooting range, but other factors may also be considered. For example, the Scheinproof angle θ may be determined by considering at least one of the various factors related to Scheinproof photography, such as the width of the shooting range, the brightness of the lighting, the characteristics of the optical elements, the degree of image quality (difficulty of image quality correction), and the degree of trapezoidal distortion (difficulty of trapezoidal correction). The same may apply to other design values.

[0095] In this example, the image sensor 221 is eccentrically positioned with respect to the optical axis 22a. In a typical Scheinproof optical system, the center of the photodetector surface of the image sensor is located on the optical axis. In contrast, in this example, the center position 221x of the photodetector surface of the image sensor 221 is located away from the optical axis 22a. More specifically, the center position 221x of the photodetector surface of the image sensor 221 is located away from the intersection point C2 between the optical axis 22a and the image plane 221P. The photodetector surface of the image sensor 221 is located on the image plane 221P. That is, the displacement of the image sensor 221 occurs along the image plane 221P (on the image plane 221P).

[0096] Figure 5 shows one example configuration of the image sensor 221 shown in Figure 4. The image sensor 221 in this example includes a microlens array 221a, a color filter array 221b, and a photodetector array 221c, similar to a typical color image sensor. The photodetector array 221c is an optical device in which a large number of photodiodes are arranged. The microlens array 221a is an optical device in which a large number of microlenses are arranged to act as an imaging lens group corresponding to the photodiode group of the photodetector array 221c. The color filter array 221b is an optical device in which a group of color filters (red (R) filter group, green (G) filter group, blue (B) filter group) corresponding to the photodiode group of the photodetector array 221c are arranged.

[0097] In some embodiments, as shown in Figure 5, the image sensor 221 is positioned eccentrically with respect to the optical axis 22a such that the angle between the light rays (photographic rays 22c) guided to the photodetector array 221c (photodetector surface) by the imaging system 2 and the optical axis 221d of the microlens array 221a (referred to as the incident angle β of the photographic rays) is smaller than the angle in a conventional configuration (i.e., a configuration in which the center position of the photodetector surface of the image sensor is located on the photographic optical axis). The incident angle β of the photographic rays can be determined arbitrarily, preferably 30 degrees or less, and more preferably 10 degrees or less. The orientation of the optical axis of each microlens in the microlens array 221a is constant. That is, the optical axes of each microlens in the microlens array 221a are parallel. The orientation of the optical axis 221d corresponds to the orientation of these optical axes.

[0098] Furthermore, in some embodiments, as shown in Figure 6, the image sensor 221 is positioned eccentrically with respect to the optical axis 22a such that the angle between the imaging light ray 22c guided to the microlens array 221a by the imaging system 2 and the optical axis 221d of the microlens array 221a (referred to as the imaging light ray incidence angle γ) is smaller than the angle in conventional configurations. The imaging light ray incidence angle γ can be determined arbitrarily.

[0099] Furthermore, in the example shown in Figure 4, the center position 221x of the light detection surface of the image sensor 221 is positioned offset towards the illumination system 2 side (closer to the illumination optical axis 21a) with respect to the intersection point C2 of the imaging optical axis 22a and the image plane 221P.

[0100] In some embodiments, by adopting a configuration in which the image sensor 221 is eccentrically positioned with respect to the shooting optical axis 22a, the shooting light rays 22c can be guided at an angle of 90 degrees or close to it to the light detection surface of the image sensor 221. In other words, the shooting light rays 22c can be guided in a direction parallel to or close to the optical axis 221d of the image sensor 221. This makes it possible to improve the light reception efficiency of the image sensor 221.

[0101] The eccentricity Δ of the image sensor 221 shown in Figure 4 is the offset amount of the center position 221x of the photodetector surface of the image sensor 221 with respect to the intersection point C2 of the optical axis 22a and the image plane 221P. The eccentricity Δ may be determined based on arbitrary parameters and characteristics. Non-limiting examples of factors that can be referenced for determining the eccentricity Δ include the incident angle of the photographic light ray (β, γ), the position of the entrance pupil of the Scheinproof imaging system 22, the diameter of the entrance pupil, and the target resolution value.

[0102] Some non-limiting detailed examples of the movement mechanism 6 are described below. The movement mechanism 6 is configured to move the illumination system 21 and the shineproof imaging system 22. The movement mechanism 6 may include at least one of a translation mechanism and a rotation mechanism. Although not shown in the figures, the movement mechanism 6 may also include a mechanism for tilting the illumination imaging optical system 2 in the vertical direction and panning it in the horizontal direction.

[0103] The translation mechanism is configured to translate the illumination and imaging optical system 2 in three dimensions and is used for alignment to position the illumination and imaging optical system 2 relative to the eye E under examination. The translation mechanism also integrally translates the illumination system 21 and the shineproof imaging system 22 in a predetermined direction to apply a translation scanning method to the anterior segment of the eye E under examination. By combining the operation of the illumination system 21, the operation of the shineproof imaging system 22, and the operation of the translation mechanism 6 (translation mechanism), a translation scanning method for the anterior segment using slit light is realized. In this anterior segment scan, for example, a slit light with the Y direction as the longitudinal direction is moved in the X direction to apply a scan to the three-dimensional region of the anterior segment. As a result, multiple images are collected, each depicting multiple cross-sections within the three-dimensional region. The multiple cross-sectional images depicted in the multiple collected images correspond to multiple cross-sections arranged parallel to each other in the three-dimensional region.

[0104] The rotation mechanism is configured to rotate the illumination and imaging optical system 2 around a predetermined axis. The rotation mechanism integrally rotates the illumination system 21 and the shineproof imaging system 22 in a predetermined direction in order to apply a rotational scan method to the anterior segment of the eye E under examination. The axis of rotation in this anterior segment scan may be, for example, the illumination optical axis 21a. By combining the operation of the illumination system 21, the operation of the shineproof imaging system 22, and the operation of the rotation mechanism, a rotational scan method for the anterior segment using slit light is realized. In this anterior segment scan, for example, the scan is applied to the three-dimensional region of the anterior segment by rotating the slit light around the longitudinal center position of the slit light (illumination optical axis 21a) as the center of rotation. As a result, multiple images are collected, each depicting multiple cross-sections within the three-dimensional region. The multiple cross-sectional images depicted in the multiple collected images correspond to multiple cross-sections arranged radially in the three-dimensional region.

[0105] A non-exclusive detailed example of the data processing unit 8 will be described. In this example, the data processing unit 8 is configured to perform at least one of the following: processing of data generated by the Shineproof imaging system 22, and processing of an image constructed based on the data generated by the Shineproof imaging system 22.

[0106] The processing that can be performed by the data processing unit 8 may be of any type. For example, the data processing unit 8 may be configured to perform at least one processing from a group consisting of various processing methods including frequency analysis, representation, filtering, noise reduction, smoothing, normalization, correction, texture mapping, edge detection, segmentation, feature extraction, image transformation, image restoration, pattern recognition, classification, and image compression.

[0107] Furthermore, the data processing unit 8 may be capable of performing processing useful in shineproof photography. For example, the data processing unit 8 may be configured to perform trapezoidal distortion correction and refractive distortion correction.

[0108] Furthermore, the data processing unit 8 may be capable of performing processes useful for diagnosis. For example, the data processing unit 8 may be configured to perform at least one of a group of processes, including quality evaluation of data and images, analysis of data and images, calculation processing to obtain numerical values ​​from data and images, feature extraction from data and images, visualization of data and images, visualization of information obtained from data and images, and diagnostic support processing based on data and images.

[0109] Next, the operation of the ophthalmic device 1 will be explained. Figure 7 shows an example of non-limited operation.

[0110] In this example, first, the subject's head is placed on the holding parts (forehead rest, chin rest) of the ophthalmic device 1 (not shown). The ophthalmic device 1, for example, receives instructions made using the user interface 10, and starts projecting fixation light onto the subject eye E that is the target of the anterior segment scan, and performs alignment of the illumination imaging optical system 2 with respect to the subject eye E (S1).

[0111] Alignment may be performed automatically or manually. After alignment is complete, the ophthalmic device 1 may start tracking the illumination and imaging optical system 2 to follow the movement of the eye E being examined.

[0112] Alignment and tracking may be performed using an anterior segment observation system (not shown). The anterior segment observation system acquires observational images (moving images) of the anterior segment of the eye E under examination. The observational images are typically generated by capturing moving images of the anterior segment from a frontal or oblique direction, and may be color images or near-infrared images. For details on anterior segment observation systems, please refer to, for example, Patent Documents 3 and 4.

[0113] Once preparatory actions such as alignment are complete, the ophthalmic device 1 starts projecting slit light 21b onto the anterior segment of the eye E being examined using the illumination system 21 (S2).

[0114] The initial state of the slit light 21b (e.g., initial position, initial orientation) can be determined arbitrarily. The initial position is the position from which the slit light 21b is projected at the start of the anterior segment scan, and the initial orientation is the direction from which the slit light 21b is projected at the start of the anterior segment scan. When a parallel-shift scanning method for anterior segment scanning is used, the orientation of the projected slit light 21b remains unchanged from the initial orientation.

[0115] In an embodiment where a rotational scanning method for anterior segment scanning is applied to the eye E under examination, for example, the initial orientation is set so that the longitudinal direction of the slit light 21b substantially coincides with the Y direction, and the initial position is set so that the center of the slit light 21b (the center in the longitudinal direction and the center in the short direction, that is, the center in the slit length direction and the center in the slit width direction) substantially coincides with the axis of the eye E under examination. In this embodiment, the center of the slit light 21b corresponds to the illumination optical axis 21a of the illumination system 21.

[0116] In an embodiment where a parallel-shift scanning method for anterior segment scanning is applied to the eye E under examination, for example, the initial orientation is set such that the longitudinal direction of the slit light 21b substantially coincides with the Y direction, and the initial position is set at the edge position of the cornea Co in the X direction or at a position further from the corneal center than the said edge position.

[0117] Next, an anterior segment scan using slit light 21b is applied to the eye E under examination (S3).

[0118] The anterior segment scan is performed by the control unit 7 controlling the illumination system 21, the shineproof imaging system 22, and the movement mechanism 6. More specifically, the anterior segment scan in this example is performed by the control unit 7 controlling the illumination system 21 to output slit light 21b, controlling the shineproof imaging system 22 to repeat imaging (data generation) at predetermined time intervals (predetermined imaging rate), and controlling the movement mechanism 6 to move the illumination system 21 and the shineproof imaging system 22 together.

[0119] In an embodiment where a rotational scanning method for anterior segment scanning is applied to the eye E under examination, the control unit 7 performs, for example, the following: control of the illumination system 21 for projecting slit light 21b onto the anterior segment; control of the shineproof imaging system 22 for repeatedly imaging the anterior segment at a predetermined imaging rate; and control of the moving mechanism 6 (rotating mechanism) for integrally rotating the illumination system 21 and the shineproof imaging system 22 with the illumination light axis 21a as the axis of rotation.

[0120] The rotation angles of the illumination system 21 and the shineproof imaging system 22 in the rotational scanning method for anterior segment scanning can be arbitrary. For example, as shown in Figure 8, by rotating the illumination system 21 and the shineproof imaging system 22 by 180 degrees around the axis Rc of the eye under examination E (rotation along the trajectory R), a dataset corresponding to the three-dimensional region around the axis Rc of the eye under examination E is collected.

[0121] The dataset collected by the anterior segment scan in Figure 8, as shown in Figure 9, contains multiple data points corresponding to multiple cross-sections P1 to PN arranged radially around the axis Rc of the eye E being examined. The multiple cross-sections P1 to PN correspond to multiple rotational positions in the anterior segment scan. The multiple rotational positions can be defined as multiple positions on the trajectory R of the anterior segment scan, and the positions of the multiple cross-sections P1 to PN can be defined in the same way.

[0122] The rotation angle of the illumination system 21 and the Scheinproof imaging system 22 in the anterior segment scan using the rotational scanning method is not limited to 180 degrees as shown in Figure 8. In some embodiments, the illumination system 21 and the Scheinproof imaging system 22 can be rotated by an angle greater than 180 degrees. In this case, two or more data points corresponding to a single rotation position can be acquired. This makes it possible to perform statistical calculations (such as averaging) for each rotation position and to select data for each rotation position.

[0123] In some embodiments, the illumination system 21 and the shineproof imaging system 22 can be rotated by an angle of less than 180 degrees. In this case, an anterior segment scan can be performed targeting only the area of ​​interest in the anterior segment, thereby shortening the examination time.

[0124] In an embodiment where a parallel-shift scanning method for anterior segment scanning is applied to the eye E under examination, the control unit 7 performs, for example, the following: control of the illumination system 21 for projecting slit light 21b onto the anterior segment; control of the shineproof imaging system 22 for repeatedly imaging the anterior segment at a predetermined imaging rate; and control of the movement mechanism 6 (parallel-shift mechanism) for integrally moving the illumination system 21 and the shineproof imaging system 22 from their initial positions in a predetermined direction.

[0125] In the anterior segment scan using the parallel translation scanning method, the movement distance of the illumination system 21 and the shineproof imaging system 22 may be arbitrary. For example, as shown in Figure 10, the illumination system 21 and the shineproof imaging system 22 are moved in parallel together in the X direction to move the projection area of ​​the slit light 21b from an initial position further from the corneal center than the first end position in the X direction of the cornea Co of the eye E, to an end position further from the corneal center than the second end position in the X direction of the cornea Co (the end position opposite the first end position in the X direction) (trajectory T in the X direction). This collects a dataset corresponding to a three-dimensional region that includes (almost) the entire cornea Co.

[0126] The dataset collected in the anterior segment scan shown in Figure 10 contains multiple data points corresponding to multiple cross-sections U1 to UM, which are arranged parallel to each other, as shown in Figure 11. The multiple cross-sections U1 to UM correspond to multiple positions (positions expressed in X coordinates) in the anterior segment scan. The positions of the multiple cross-sections P1 to PN can be defined in a similar manner.

[0127] The dataset collected in step S3 is stored, for example, in the storage device of the control unit 7 or the storage device of the data processing unit 8. The data processing unit 8 applies predetermined data processing to this dataset. In this example, predetermined analysis processing is applied to the dataset (S4).

[0128] This analysis process may be any known process, and may include, for example, corneal curvature analysis, corneal pachymetry, corneal elevation analysis, corneal topography, anterior chamber depth analysis, and gonioscopy. In distance measurement, pixel spacing is performed to determine the distance corresponding to one pixel (pixel interval).

[0129] Furthermore, the data processing unit 8 can correct each data collected by the anterior segment scan. For example, the data processing unit 8 may be configured to correct distortions (e.g., trapezoidal distortion, refractive distortion, etc.) in each data collected by the anterior segment scan. For details on distortion correction, please refer to, for example, Patent Document 4.

[0130] The control unit 7 displays the anterior segment image based on the dataset collected in step S3 and the analysis data obtained in the analysis process of step S4 on the display unit 11 (S5). The displayed anterior segment image may have undergone correction processing such as distortion correction.

[0131] According to the ophthalmic apparatus 1 of this embodiment, by using a shineproof imaging system 22 with high light detection efficiency in which the image sensor 221 is eccentrically positioned with respect to the imaging optical axis 22a, it is possible to acquire anterior segment images of high quality with a deep depth of field.

[0132] Furthermore, by performing an anterior segment scan using such a Shineproof imaging system 22, multiple anterior segment images can be collected from a three-dimensional region of the eye E under examination (for example, a wide three-dimensional region including the area from the anterior surface of the cornea to the posterior surface of the lens).

[0133] Furthermore, by analyzing one or more anterior segment images with high quality and deep depth of field, high-quality analysis data can be provided. For example, the accuracy, precision, and reproducibility of anterior segment image analysis can be improved.

[0134] In addition, it can provide users with high-quality anterior segment images with a deep depth of field, as well as high-quality visualizations of analytical data.

[0135] <Modified Examples> Modified examples of the ophthalmic apparatus 1 of this embodiment will be described. In the above embodiment, one pair of shineproof imaging system and illumination system is provided, but two or more pairs may be provided.

[0136] For example, in one modified version, a pair of a first shineproof imaging system and a first illumination system (the first pair) and a pair of a second shineproof imaging system and a second illumination system (the second pair) are provided.

[0137] The first pair will be described. The first Shineproof imaging system is configured to satisfy the Shineproof conditions and is configured to image the anterior segment of the eye E under examination to generate first data. The first illumination system is configured to project first illumination light onto the object surface of the first Shineproof imaging system.

[0138] The second pair will now be described. The second Scheinproof imaging system is configured to satisfy the Scheinproof conditions and is configured to image the anterior segment of the eye E under examination to generate second data. The second illumination system is configured to project second illumination light onto the object surface of the second Scheinproof imaging system.

[0139] The arrangement of the first pair and the second pair can be determined arbitrarily. For example, the object surfaces of the first Shineproof imaging system and the second Shineproof imaging system may be common to each other or may be separate.

[0140] The wavelength bands of the first illumination light projected by the first illumination system and the wavelength bands of the second illumination light projected by the second illumination system may be equal or different. For example, the first and second illumination lights may be visible light with equal wavelength bands, visible light with different wavelength bands, infrared light with equal wavelength bands, or infrared light with different wavelength bands. Alternatively, one of the first and second illumination lights may be visible light and the other infrared light.

[0141] The movement mechanism 6 may perform the movement of the first pair (translation, rotation) and the movement of the second pair (translation, rotation) in parallel (for example, integrally) or separately. In the translation scanning method, the direction of movement of the first pair and the direction of movement of the second pair may be the same or different. In the rotation scanning method, the rotation axis of the first pair and the rotation axis of the second pair may be common or different.

[0142] The above describes some non-limiting embodiments of the ophthalmic apparatus according to the embodiment. It is possible to combine at least two or more embodiments of the present disclosure in part.

[0143] <Other Embodiments> The embodiments relating to this disclosure are not limited to ophthalmic devices. Embodiments other than ophthalmic devices include methods for controlling ophthalmic devices, methods for photographing the anterior segment of the eye, programs, recording media, etc. These embodiments can achieve the same effects as the embodiments of ophthalmic devices.

[0144] Some embodiments provide methods for controlling ophthalmic devices.

[0145] In one embodiment of a control method for an ophthalmic device, the ophthalmic device includes a Scheinproof imaging system, an illumination system, a display unit, and a processor. The Scheinproof imaging system is configured to satisfy Scheinproof conditions and to capture images of the anterior segment of the eye under examination and generate data. This Scheinproof imaging system includes an image sensor. The image sensor is positioned on the image plane of the Scheinproof imaging system and is eccentrically positioned with respect to the optical axis of the Scheinproof imaging system. The illumination system is configured to project illumination light onto the object surface of the Scheinproof imaging system.

[0146] The method according to this embodiment includes a step (display control step) in which a processor is instructed to perform control to display an image of the eye under examination, based on data generated by the Shineproof imaging system, on a display unit.

[0147] According to the method of this embodiment, it is possible to acquire an anterior segment image with high quality and a deep depth of field using a Shineproof imaging system with high light detection efficiency in which the image sensor is eccentrically positioned with respect to the optical axis, and furthermore, this anterior segment image can be displayed. Therefore, it is possible to provide useful information to the user.

[0148] In another embodiment of the control method for an ophthalmic apparatus, the ophthalmic apparatus includes a Scheinproof imaging system, an illumination system, a moving mechanism, a display unit, and a processor. The Scheinproof imaging system is configured to satisfy Scheinproof conditions and to image the anterior segment of the eye under examination and generate data. The Scheinproof imaging system includes an image sensor. The image sensor is positioned on the image plane of the Scheinproof imaging system and is eccentrically positioned with respect to the optical axis of the Scheinproof imaging system. The illumination system is configured to project illumination light onto the object surface of the Scheinproof imaging system. The moving mechanism is configured to move the Scheinproof imaging system and the illumination system.

[0149] The method according to this embodiment includes a step (anterior segment scan control step) in which a processor is instructed to control a shineproof imaging system, an illumination system, and a movement mechanism in order to generate a dataset corresponding to multiple positions in the shineproof imaging system. Furthermore, the method according to this embodiment includes a step (display control step) in which a processor is instructed to control the display unit to display an image of the eye under examination based on the dataset generated by the anterior segment scan control step.

[0150] According to the method of this embodiment, by performing an anterior segment scan using a Shineproof imaging system with high light detection efficiency in which the image sensor is eccentrically positioned with respect to the optical axis, it is possible to generate a dataset consisting of multiple anterior segment images with high quality and deep depth of field from a three-dimensional region of the eye under examination (for example, a wide three-dimensional region including the range from the anterior surface of the cornea to the posterior surface of the lens), and furthermore, information can be displayed based on this dataset. Therefore, it is possible to provide useful information to the user.

[0151] Any of the matters described in this disclosure can be combined with the methods according to the embodiments.

[0152] Some embodiments provide programs. The programs according to these embodiments cause a computer, including a processor and memory, to execute one of the methods described in the embodiments above. Any of the matters described in this disclosure can be combined with the programs according to these embodiments.

[0153] Some embodiments provide computer-readable non-temporary recording media. The recording media according to these embodiments contain a program that causes a computer to execute one of the methods described in the embodiments above. Any of the matters described in this disclosure can be combined with the recording media according to these embodiments.

[0154] The computer-readable non-temporary recording medium that can be used as a recording medium according to this embodiment may be any form of recording medium, for example, a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory.

[0155] The embodiments and aspects described herein are illustrative only. Any modifications (omissions, substitutions, additions, etc.) within the scope of the gist of the present invention can be applied to the embodiments and aspects of this disclosure.

Claims

1. An ophthalmic apparatus configured to satisfy shineproof conditions, comprising: a shineproof imaging system that photographs the anterior segment of the eye under examination and generates data; and an illumination system that projects illumination light onto the object surface of the shineproof imaging system, wherein the shineproof imaging system includes an image sensor positioned on the image plane of the shineproof imaging system and eccentrically positioned with respect to the optical axis of the shineproof imaging system.

2. The ophthalmic apparatus according to claim 1, wherein the image sensor includes a microlens array, and is eccentrically positioned with respect to the optical axis of the Shineproof imaging system such that the angle between the light rays guided to the microlens array by the Shineproof imaging system and the optical axis of the microlens array is smaller than when the image sensor is concentric with respect to the optical axis of the Shineproof imaging system.

3. The ophthalmic apparatus according to claim 1 or 2, wherein the image sensor includes a photodetector array and a microlens array configured as an imaging lens group for the photodetector array, and the microlens array is eccentrically positioned with respect to the optical axis of the Shineproof imaging system such that the angle between the light rays guided to the photodetector array by the Shineproof imaging system and the optical axis of the microlens array is smaller than when the microlens array is concentric with respect to the optical axis of the Shineproof imaging system.

4. The ophthalmic apparatus according to any one of claims 1 to 3, wherein the center position of the light detection surface of the image sensor is located away from the intersection point of the optical axis of the shineproof imaging system and the image plane.

5. The ophthalmic apparatus according to claim 4, wherein the distance between the center position of the light-detecting surface of the image sensor and the intersection point is determined based on at least one of the following: the direction of the light rays guided to the image sensor by the Shineproof imaging system, the position of the entrance pupil of the Shineproof imaging system, the diameter of the entrance pupil, and the resolution.

6. The ophthalmic apparatus according to claim 5, wherein the distance is determined such that the angle between the light ray guided to the image sensor by the shineproof imaging system and the optical axis of the image sensor is 30 degrees or less, preferably 10 degrees or less.

7. An ophthalmic apparatus according to any one of claims 1 to 6, further comprising: a moving mechanism for moving the shineproof imaging system and the illumination system; and a first control unit that controls the shineproof imaging system, the illumination system, and the moving mechanism to cause the shineproof imaging system to generate a dataset corresponding to a plurality of positions.

8. An ophthalmic apparatus according to any one of claims 1 to 7, comprising: a first shine-proof imaging system configured to satisfy shine-proof conditions and for imaging the anterior eye to generate first data; a first illumination system for projecting first illumination light onto the surface of the first shine-proof imaging system; a second shine-proof imaging system configured to satisfy shine-proof conditions and for imaging the anterior eye to generate second data; and a second illumination system for projecting second illumination light onto the surface of the second shine-proof imaging system.

9. An ophthalmic apparatus according to any one of claims 1 to 8, further comprising a fixation optical system for presenting a fixation target to the eye under examination.

10. An ophthalmic apparatus according to any one of claims 1 to 9, further comprising a second control unit that displays an image of the eye under examination on a display device based on the data generated by the Shineproof imaging system.

11. An ophthalmic apparatus according to any one of claims 1 to 10, further comprising a processing unit that performs at least one of processing the data generated by the Shineproof imaging system and processing an image based on the data.

12. A method for controlling an ophthalmic device for photographing an eye under examination, the ophthalmic device being configured to satisfy shine-proof conditions and comprising: a shine-proof imaging system for photographing the anterior segment of the eye under examination and generating data; an illumination system for projecting illumination light onto the object surface of the shine-proof imaging system; a display unit; and a processor, wherein the shine-proof imaging system includes an image sensor positioned on the image plane of the shine-proof imaging system and eccentrically positioned with respect to the optical axis of the shine-proof imaging system, and the method comprising the step of causing the processor to perform control for displaying an image of the eye under examination based on the data generated by the shine-proof imaging system on the display unit.

13. A method for controlling an ophthalmic device for photographing an eye under examination, the ophthalmic device being configured to satisfy shineproof conditions and comprising: a shineproof imaging system for photographing the anterior segment of the eye under examination and generating data; an illumination system for projecting illumination light onto the object surface of the shineproof imaging system; a movement mechanism for moving the shineproof imaging system and the illumination system; a display unit; and a processor, wherein the shineproof imaging system includes an image sensor positioned on the image plane of the shineproof imaging system and eccentrically positioned with respect to the optical axis of the shineproof imaging system, the method comprising: causing the processor to control the shineproof imaging system, the illumination system, and the movement mechanism to generate a dataset corresponding to a plurality of positions in the shineproof imaging system; and causing the processor to control the display unit for displaying an image of the eye under examination based on the dataset.

14. A computer-readable non-temporary recording medium on which a program causing a computer to execute the method of claim 12 or 13 is recorded.

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