Ophthalmic device, its control method, and program

Abstract

To provide a new technique that acquires a higher-quality image of a subject eye with a simplified structure.SOLUTION: An ophthalmic device includes: an illumination optical system; an optical scanner; an imaging optical system; and a control unit. The illumination optical system comprises a light source and a slit in which an opening can be positioned optically conjugate to a prescribed portion of a subject eye, and generates slit-shaped illumination light by making the light from the light source pass through the opening. The optical scanner deflects the illumination light to guide it to the prescribed portion of the subject eye. The imaging optical system guides the return light of the illumination light from the prescribed portion to an image sensor that can set an opening range on a light receiving surface. The control unit changes the width of the opening range on the light receiving surface according to the deflection angle of the illumination light by the optical scanner, and controls the optical scanner and image sensor so that the irradiation range on the light receiving surface corresponding to the irradiation region of the illumination light overlaps with the opening range in the imaging region of the prescribed portion, and the light reception result of the return light in the opening range overlapping with the irradiation range is acquired.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] This invention relates to an ophthalmic device, a control method thereof, and a program. [Background technology]

[0002] In recent years, screening tests using ophthalmic devices have been performed. Such ophthalmic devices are also expected to be used for self-examination, and further miniaturization and weight reduction are desired.

[0003] For example, Patent Documents 1 to 4 disclose an ophthalmic device configured to pattern-illuminate the eye under examination and acquire the light reception result using a rolling shutter method with an image sensor. This ophthalmic device makes it possible to acquire an image of the eye under examination with a simple configuration by adjusting the illumination pattern and the timing of light reception by the image sensor. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] U.S. Patent No. 7831106 [Patent Document 2] U.S. Patent No. 8,237,835 [Patent Document 3] U.S. Patent No. 7335898 [Patent Document 4] Special Publication No. 2009-538697 [Overview of the project] [Problems that the invention aims to solve]

[0005] However, with conventional methods, the amount of illumination light changes depending on the position within the imaging area, which can sometimes prevent the acquisition of high-quality images of the eye under examination. Therefore, there is a need for a technology that can suppress the degradation of image quality of the eye under examination without complicating the configuration.

[0006] The present invention has been made in view of such circumstances, and one of its objects is to provide a new technique for acquiring a higher-quality image of an eye to be examined with a simple configuration.

Means for Solving the Problem

[0007] A first aspect of some embodiments includes an illumination optical system that generates slit-shaped illumination light, an optical scanner that deflects the illumination light and guides it to a predetermined site of an eye to be examined, an imaging optical system that guides the return light of the illumination light from the predetermined site to an image sensor capable of setting an aperture range on a light-receiving surface, and a control unit that controls the optical scanner and the image sensor so that an irradiation range on the light-receiving surface corresponding to an irradiation region of the illumination light in an imaging region of the predetermined site overlaps the aperture range, and acquires a light-receiving result of the return light in the aperture range that overlaps the irradiation range. It is an ophthalmic device.

[0008] In a second aspect of some embodiments, in the first aspect, the control unit moves the aperture range and controls the optical scanner and the image sensor so that the irradiation range overlaps the moved aperture range.

[0009] In a third aspect of some embodiments, in the first aspect, the control unit moves the irradiation range and controls the optical scanner and the image sensor so that the aperture range overlaps the moved irradiation range.

[0010] In a fourth aspect of some embodiments, in any one of the first to third aspects, the control unit controls the optical scanner so as to scan the irradiation region with the illumination light.

[0011] In a fifth aspect of some embodiments, in the fourth aspect, the control unit controls the optical scanner and the image sensor so that an aperture target region at the predetermined site corresponding to the aperture range covers the imaging region during one frame period in which a light-receiving result of the aperture range is captured by the image sensor.

[0012] In a sixth aspect of some embodiments, in the fifth aspect, the control unit controls the optical scanner to deflect the illumination light at a deflection speed corresponding to the position of the irradiation region of the illumination light at the predetermined site, and controls the image sensor to set the aperture range having an aperture width corresponding to the position of the irradiation region.

[0013] In a seventh aspect of some embodiments, in the fourth aspect, the control unit changes the aperture target region at the predetermined site corresponding to the irradiation region or the aperture range for each frame period in which the light reception result of the aperture range is captured by the image sensor, and controls the optical scanner and the image sensor so that the aperture target region covers the imaging region over two or more frame periods.

[0014] In an eighth aspect of some embodiments, in the seventh aspect, the control unit controls the optical scanner to deflect the illumination light at a deflection speed corresponding to the position of the irradiation region of the illumination light at the predetermined site for each frame period, and controls the image sensor to set the aperture range having an aperture width corresponding to the position of the irradiation region.

[0015] In a ninth aspect of some embodiments, in the fourth aspect, the control unit makes the irradiation region coincide with the aperture target region at the predetermined site corresponding to the aperture range for each frame period in which the light reception result of the aperture range is captured by the image sensor, and controls the optical scanner and the image sensor so that the aperture target region covers the imaging region over two or more frame periods.

[0016] In a tenth aspect of some embodiments, in the ninth aspect, the control unit controls the optical scanner so that the illumination light irradiates the irradiation region for an irradiation time corresponding to the position of the irradiation region of the illumination light at the predetermined site for each frame period, and controls the image sensor to set the aperture range that opens for an aperture time corresponding to the position of the irradiation region.

[0017] In the eleventh aspect of some embodiments, in any of the first to tenth aspects, the control unit acquires the light reception result obtained by the image sensor using a global shutter method.

[0018] In a twelfth aspect of several embodiments, in the fourth aspect, the control unit acquires the light reception result obtained by the image sensor in a rolling shutter manner, and controls the optical scanner and the image sensor so that, for each frame period in which the light reception result of the aperture range is captured by the image sensor, the illumination area overlaps with the aperture target area in the predetermined part corresponding to the aperture range, and the aperture target area covers the shooting area for two or more frame periods.

[0019] In a thirteenth aspect of several embodiments, in the twelfth aspect, the control unit controls the optical scanner so that, for each frame period, the illumination light illuminates the illumination area for an illumination time corresponding to the position of the illumination light illumination area in the predetermined part, and controls the image sensor so that it reads out the light reception result of the aperture range corresponding to the position of the illumination area using a rolling shutter method.

[0020] A fourteenth embodiment of some of the embodiments includes an image forming unit that forms an image of the predetermined area based on the light reception results captured in the aperture range overlapping the irradiation range, in any of the first to thirteenth embodiments.

[0021] In a 15th aspect of several embodiments, in any of the 1st to 14th aspects, the illumination optical system includes a slit whose aperture can be positioned at a location substantially conjugate to the predetermined portion, and generates illumination light by light from a light source passing through the aperture, the optical scanner can be positioned at a location substantially conjugate to the iris of the eye under examination, and the light-receiving surface can be positioned at a location substantially conjugate to the predetermined portion.

[0022] In a sixteenth aspect of several embodiments, in the fifteenth aspect, the illumination optical system includes an iris diaphragm positioned between the light source and the slit, with an opening formed at an eccentric position with respect to the optical axis of the illumination optical system and positioned to be substantially conjugate to the iris; and a hole mirror with an opening formed to be positioned to be substantially conjugate to the iris and for coupling the optical path of the illumination light deflected by the optical scanner with the optical path of the imaging optical system.

[0023] In the 17th aspect of some embodiments, in any of the 1st to 16th aspects, the predetermined area is the fundus of the eye.

[0024] A 18th aspect of several embodiments is a control method for an ophthalmic apparatus, comprising: an illumination optical system that generates slit-shaped illumination light; an optical scanner that deflects the illumination light and guides it to a predetermined part of the eye under examination; and an imaging optical system that guides the reflected light of the illumination light from the predetermined part to an image sensor capable of setting an aperture range on the light-receiving surface. The control method for the ophthalmic apparatus includes a control step of controlling the optical scanner and the image sensor so that the illumination range on the light-receiving surface corresponding to the illumination range of the predetermined part overlaps with the aperture range, and the light reception result of the reflected light in the aperture range that overlaps with the illumination range is obtained.

[0025] In a 19th aspect of several embodiments, in the 18th aspect, the control step includes an image sensor control step of controlling the image sensor to move the aperture range, and an optical scanner control step of controlling the optical scanner to overlap the illumination range with the moved aperture range.

[0026] In a 20th aspect of several embodiments, in the 18th aspect, the control step includes an optical scanner control step of moving the illumination range and an image sensor control step of controlling the image sensor so that the aperture range overlaps the illumination range after movement.

[0027] In a 21st aspect of some embodiments, in any of the 18th to 20th aspects, the control step controls the optical scanner to scan the illumination area with the illumination light.

[0028] In a 22nd aspect of several embodiments, in the 21st aspect, the control step controls the optical scanner and the image sensor so that the aperture target area in the predetermined part corresponding to the aperture range covers the shooting area during a 1-frame period in which the image sensor captures the light reception result of the aperture range.

[0029] In a 23rd aspect of several embodiments, in the 21st aspect, the control step changes the aperture target area in the predetermined part corresponding to the illumination area or the aperture range for each frame period in which the image sensor captures the light reception result of the aperture range, and controls the optical scanner and the image sensor so that the aperture target area covers the shooting area over two or more frame periods.

[0030] In a 24th aspect of several embodiments, in the 21st aspect, the control step controls the optical scanner and the image sensor so that, for each frame period in which the image sensor captures the light-receiving result of the aperture range, the illuminated area coincides with the aperture target area in the predetermined part corresponding to the aperture range, and the aperture target area covers the shooting area over two or more frame periods.

[0031] In a 25th aspect of some embodiments, in any of the 18th to 24th aspects, the image sensor is capable of acquiring light reception results using a global shutter method.

[0032] In a 26th aspect of several embodiments, in the 18th aspect, the image sensor is capable of acquiring light reception results in a rolling shutter manner, and the control step controls the optical scanner and the image sensor so that the illumination area includes an aperture target area in the predetermined part corresponding to the aperture range for each frame period in which the image sensor captures the light reception results of the aperture range, and the aperture target area covers the shooting area over two or more frame periods.

[0033] A 27th aspect of some embodiments includes an image forming step in any of the 18th to 26th aspects, in which an image of the predetermined area is formed based on the light reception results captured in the aperture range.

[0034] In the 28th embodiment of some of the embodiments, in any of the 18th to 27th embodiments, the predetermined site is the fundus of the eye.

[0035] A 29th aspect of some embodiments is a program that causes a computer to perform each step of the control method for an ophthalmic apparatus according to any of the 18th to 28th aspects.

[0036] Furthermore, it is possible to arbitrarily combine the configurations relating to the multiple embodiments described above. [Effects of the Invention]

[0037] This invention provides a new technique for acquiring higher-resolution images of the eye under examination with a simple configuration. [Brief explanation of the drawing]

[0038] [Figure 1] This is a schematic diagram showing an example of the configuration of the optical system of an ophthalmic device according to the first embodiment. [Figure 2] This is a schematic diagram showing an example of the configuration of the optical system of an ophthalmic device according to the first embodiment. [Figure 3] This is an explanatory diagram illustrating the operation of the ophthalmic device according to the first embodiment. [Figure 4]This is a schematic diagram showing an example of the configuration of the control system of an ophthalmic device according to the first embodiment. [Figure 5A] This is an explanatory diagram illustrating the operation of the ophthalmic device according to the first embodiment. [Figure 5B] This is an explanatory diagram illustrating the operation of the ophthalmic device according to the first embodiment. [Figure 6A] This is an explanatory diagram of the operation of the ophthalmic device according to the second embodiment. [Figure 6B] This is an explanatory diagram of the operation of the ophthalmic device according to the second embodiment. [Figure 7A] This is an explanatory diagram of the operation of the ophthalmic device according to the third embodiment. [Figure 7B] This is an explanatory diagram of the operation of the ophthalmic device according to the third embodiment. [Figure 8A] This is an explanatory diagram of the operation of the ophthalmic device according to the fourth embodiment. [Figure 8B] This is an explanatory diagram of the operation of the ophthalmic device according to the fourth embodiment. [Modes for carrying out the invention]

[0039] An example of an embodiment of the ophthalmic apparatus, its control method, and program according to this invention will be described in detail with reference to the drawings. The contents of the documents cited in this specification can be appropriately incorporated into the following embodiments.

[0040] The ophthalmic apparatus according to this embodiment uses an optical scanner to deflect a slit-shaped illumination light, irradiates (scans) a predetermined area of ​​the eye under examination with the deflected illumination light, and receives the reflected light from the predetermined area using an image sensor whose aperture range (position, shape, etc.) on the light-receiving surface can be arbitrarily set. The control unit that controls the ophthalmic apparatus controls the optical scanner and the image sensor so that, in a predetermined imaging area set on a predetermined area of ​​the eye under examination, the illumination area on the light-receiving surface corresponding to the illumination area overlaps with the aperture range. The control unit also controls the image sensor to acquire the result of receiving the reflected light in the aperture range that overlaps with the illumination area.

[0041] In some embodiments, the light reception result of the reflected light obtained by the image sensor is read out using a global shutter method. In some embodiments, the light reception result of the reflected light obtained by the image sensor is read out using a rolling shutter method.

[0042] In some embodiments, the designated region is either the anterior or posterior segment of the eye. The anterior segment includes the cornea, iris, lens, ciliary body, and zonules of Zinn. The posterior segment includes the vitreous humor, fundus, or its vicinity (retina, choroid, sclera, etc.).

[0043] The control method for the ophthalmic apparatus according to the embodiment includes one or more steps for realizing processing performed by a processor (computer) in the ophthalmic apparatus according to the embodiment. The program according to the embodiment causes the processor to execute each step of the control method for the ophthalmic apparatus according to the embodiment.

[0044] In this specification, "processor" means, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), a programmable logic device (e.g., SPLD (Simple Programmable Logic Device), CPLD (Complex Programmable Logic Device), FPGA (Field Programmable Gate Array)), or other circuit. The processor realizes the functions according to the embodiment by, for example, reading and executing a program stored in a memory circuit or memory device.

[0045] The following describes how the ophthalmic device according to this embodiment primarily acquires images of the fundus of the eye being examined.

[0046] <First Embodiment> [Optical System Configuration] Figures 1 and 2 show schematic diagrams of an example configuration of an ophthalmic device according to the first embodiment. Figure 1 shows an example configuration of the optical system of the ophthalmic device 1 according to the first embodiment. Figure 2 schematically shows an example configuration of the iris diaphragm 21 of Figure 1 as viewed from the direction of the optical axis O. In Figures 1 and 2, the same parts are denoted by the same reference numerals, and explanations are omitted as appropriate.

[0047] The ophthalmic apparatus 1 includes a light source 10, an illumination optical system 20, an optical scanner 30, a projection optical system 35, an imaging optical system 40, and an imaging device 50. In some embodiments, the illumination optical system 20 includes at least one of the light source 10, the optical scanner 30, and the projection optical system 35. In some embodiments, the imaging optical system 40 includes the imaging device 50. In some embodiments, the projection optical system 35 or the imaging optical system 40 includes the optical scanner 30.

[0048] (light source 10) Light source 10 includes a visible light source that generates light in the visible region. For example, light source 10 generates light having a central wavelength in the wavelength range of 420 nm to 700 nm. Such light source 10 includes, for example, an LED (Light Emitting Diode), an LD (Laser Diode), a halogen lamp, or a xenon lamp. In some embodiments, light source 10 includes a white light source or a light source capable of outputting light for each of the RGB color components. In some embodiments, light source 10 includes a light source capable of switching between outputting light in the infrared region and light in the visible region. Light source 10 is positioned optically non-conjugate to the fundus Ef and the iris, respectively.

[0049] (Illumination optical system 20) The illumination optical system 20 generates a slit-shaped illumination beam using light from the light source 10. The illumination optical system 20 guides the generated illumination beam to the optical scanner 30.

[0050] The illumination optical system 20 includes an iris diaphragm 21, a slit 22, and a relay lens 23. Light from the light source 10 passes through an opening formed in the iris diaphragm 21, through an opening formed in the slit 22, and through the relay lens 23. The relay lens 23 includes one or more lenses. The light that has passed through the relay lens 23 is guided to the optical scanner 30.

[0051] (Iris diaphragm 21) The iris diaphragm 21 (specifically, the opening described later) can be positioned at a location that is approximately optically conjugate to the iris (pupil) of the eye E under examination. The iris diaphragm 21 has one or more openings formed at positions away from the optical axis O. For example, as shown in Figure 2, the iris diaphragm 21 has openings 21A and 21B. The openings 21A and 21B are formed symmetrically with respect to a straight line that passes through the position of the optical axis O and extends in the direction corresponding to the longitudinal direction of the slit 22. The shape of the inner diameter of the openings 21A and 21B is defined by a straight line connecting two points on the inner diameter of the openings 21A and 21B such that the distance in the direction corresponding to the short direction of the slit 22 does not change.

[0052] In other words, each of the openings 21A and 21B is circular segment in shape. The circular segment is a region enclosed by a smaller arc of a circle or ellipse and the chord of this smaller arc. The direction of the chord of the circular segment is approximately parallel to the direction corresponding to the longitudinal direction of the opening formed in the slit 22.

[0053] The openings 21A and 21B formed in the iris diaphragm 21 define the incident position (incidence shape) of the illumination light in the iris of the eye E under examination. For example, by forming the openings 21A and 21B as shown in Figure 2, when the pupil center of the eye E under examination is positioned on the optical axis O, it is possible to cause the illumination light to enter the eye from an eccentric position from the pupil center (specifically, a position symmetrical with respect to a straight line passing through the pupil center).

[0054] In some embodiments, the iris diaphragm 21 has openings 21A and 21B with a predetermined thickness along the circumferential direction centered on the optical axis O.

[0055] Furthermore, by changing the relative position between the light source 10 and the opening formed in the iris diaphragm 21, it is possible to change the light intensity distribution of the light passing through the opening formed in the iris diaphragm 21.

[0056] (Slit 22) The slit 22 (specifically, the opening described later) can be positioned at a location that is approximately optically conjugate to the fundus Ef of the eye under examination E. The slit 22 has an opening formed therein. The opening formed in the slit 22 defines the illumination pattern of the illumination light at the fundus Ef of the eye under examination E. For example, the slit 22 is formed such that the longitudinal direction of the slit image on the light-receiving surface of the image sensor 51 (described later), which is formed by the light passing through the opening, is perpendicular to the direction of movement of the aperture range on the light-receiving surface.

[0057] The slit 22 is movable in the optical axis direction of the illumination optical system 20 by a moving mechanism (moving mechanism 22D described later). The moving mechanism moves the slit 22 in the optical axis direction under control from the control unit 100 described later. For example, the control unit 100 controls the moving mechanism according to the state of the eye E under examination. This makes it possible to move the position of the slit 22 according to the state of the eye E under examination (specifically, refractive power, shape of fundus Ef).

[0058] In some embodiments, the slit 22 is configured to change at least one of the position and shape of the aperture without being moved in the optical axis direction, depending on the state of the eye E being examined. Such a function of the slit 22 is realized, for example, by a liquid crystal shutter.

[0059] In some embodiments, at least one of the size, position, and shape of the opening formed in the slit 22 can be changed.

[0060] Light from the light source 10 that passes through the opening formed in the iris diaphragm 21 is output as slit-shaped illumination light by passing through the opening formed in the slit 22. The slit-shaped illumination light passes through the relay lens 23 and is guided to the optical scanner 30.

[0061] (Optical scanner 30) The optical scanner 30 is positioned approximately conjugate to the iris of the eye E under examination. The optical scanner 30 deflects the slit-shaped illumination light (the slit-shaped light that has passed through the opening formed in the slit 22) that passes through the relay lens 23. Specifically, the optical scanner 30 deflects the slit-shaped illumination light to sequentially illuminate a predetermined illumination range (the area of ​​illumination light) of the fundus Ef, while changing the deflection angle within a predetermined deflection angle range with the iris or its vicinity of the eye E under examination as the scan center position, and guides it to the projection optical system 35. The optical scanner 30 can deflect the illumination light in one or two dimensions.

[0062] In the case of one-dimensional deflection, the optical scanner 30 includes a galvanometer scanner that deflects the illumination light within a predetermined deflection angle range with respect to a predetermined deflection direction. For example, the optical scanner 30 deflects the illumination light so that it moves in a direction perpendicular (intersecting) to the longitudinal direction of the slit image formed by the illumination light at the fundus Ef of the eye under examination.

[0063] When deflecting in two dimensions, the optical scanner 30 includes a first galvanometer scanner and a second galvanometer scanner. The first galvanometer scanner deflects the illumination light so that the illumination position of the illumination light moves in a horizontal direction perpendicular to the optical axis of the illumination optical system 20. The second galvanometer scanner deflects the illumination light deflected by the first galvanometer scanner so that the illumination position of the illumination light moves in a vertical direction perpendicular to the optical axis of the illumination optical system 20.

[0064] Examples of scanning modes that move the illumination position of the light emitted by the optical scanner 30 include horizontal scanning, vertical scanning, cross scanning, radial scanning, circular scanning, concentric circle scanning, and spiral scanning.

[0065] (Projection optical system 35) The projection optical system 35 guides the illumination light deflected by the optical scanner 30 to the fundus Ef of the eye E under examination. In this embodiment, the projection optical system 35 guides the illumination light deflected by the optical scanner 30 to the fundus Ef via an optical path coupled with the optical path of the imaging optical system 40 by a hole mirror 45, which will be described later as an optical path coupling member.

[0066] The projection optical system 35 includes a relay lens 41, a black spot plate 42, a reflective mirror 43, and a relay lens 44. Each of the relay lenses 41 and 44 includes one or more lenses.

[0067] (Black dot plate 42) The black spot plate 42 is positioned at a location that is approximately conjugate to the lens surface of the objective lens 46 or its vicinity. This prevents reflected light from the lens surface of the objective lens 46 from being guided to the light source 10 (illumination optical system 20).

[0068] In such a projection optical system 35, the illumination light deflected by the optical scanner 30 passes through the relay lens 41, through the black spot plate 42, and is reflected by the reflection mirror 43 toward the hole mirror 45.

[0069] (Imaging optical system 40) The imaging optical system 40 guides the illumination light that has been guided by the projection optical system 35 to the fundus Ef of the eye under examination E, and also guides the reflected light from the fundus Ef to the imaging device 50.

[0070] In the imaging optical system 40, the optical path of the illumination light from the projection optical system 35 and the optical path of the reflected light from the fundus Ef are coupled. By using a hole mirror 45 as an optical path coupling member to couple these optical paths, it is possible to separate the illumination light and its reflected light into pupils.

[0071] The imaging optical system 40 includes a lens barrel 45, an objective lens 46, a focusing lens 47, a relay lens 48, and an imaging lens 49. Each of the relay lenses 48 includes one or more lenses.

[0072] (hole mirror 45) The aperture lens 45 has a hole that is positioned along the optical axis of the imaging optical system 40. The hole in the aperture lens 45 is positioned approximately conjugate to the iris of the eye E being examined. In the peripheral region of the hole, the aperture lens 45 reflects illumination light from the projection optical system 35 toward the objective lens 46. The aperture lens 45 functions as an imaging aperture.

[0073] (Focusing lens 47) The focusing lens 47 is movable in the optical axis direction of the imaging optical system 40 by a moving mechanism (not shown). The moving mechanism receives control from the control unit 100 (described later) and moves the focusing lens 47 in the optical axis direction. This allows the reflected light of the illumination light that has passed through the hole in the aperture mirror 45 to be imaged onto the light-receiving surface of the image sensor 51 of the imaging device 50, depending on the state of the eye under examination E.

[0074] In such a photographic optical system 40, illumination light from the projection optical system 35 is reflected toward the objective lens 46 in the peripheral region of the hole formed in the aperture mirror 45. The illumination light reflected in the peripheral region of the aperture mirror 45 is refracted by the objective lens 46 and enters the eye through the pupil of the eye under examination E, illuminating the fundus Ef of the eye under examination E.

[0075] The reflected light from the retinal effusion is refracted by the objective lens 46, passes through the hole in the aperture lens 45, through the focusing lens 47, through the relay lens 48, and is imaged onto the light-receiving surface of the image sensor 51 of the imaging device 50 by the imaging lens 49.

[0076] (Imaging device 50) The imaging device 50 includes an image sensor 51 that receives the reflected light of illumination light that has been guided from the fundus Ef of the eye E under examination through the imaging optical system 40. The imaging device 50 can receive control from the control unit 100 (described later) and output the result of the reflected light reception.

[0077] (Image sensor 51) The image sensor 51 functions as a pixelated light receiver. The light-receiving surface (detection surface, imaging surface) of the image sensor 51 can be positioned in a location that is approximately optically conjugate to the fundus Ef.

[0078] The position and shape of the aperture range on the light-receiving surface of the image sensor 51 can be arbitrarily set under control from the control unit 100, which will be described later. For example, by changing the position of the aperture range according to the position of the illumination area of ​​the illuminating light in the fundus Ef, it is possible to obtain the reception result of the reflected light from the illumination area without being affected by unwanted scattered light. For example, by reducing the size of the aperture range, the frame period, which is the period during which the reception result of the reflected light at the light-receiving element within the aperture range is captured, is shortened.

[0079] The light-receiving results obtained by the light-receiving elements within the aperture range of the image sensor 51 are captured and read out using a global shutter method. That is, the exposure start timing and exposure end timing are synchronized for all light-receiving elements within the aperture range of the image sensor 51. Examples of such image sensors 51 include known image sensors such as CCD (Charge Coupled Device) image sensors and CMOS (Complementary Metal Oxide Semiconductor) image sensors. In some embodiments, the control unit 100, described later, controls the readout of the light-receiving results by controlling the image sensor 51.

[0080] Figure 3 shows an explanatory diagram of the operation of the ophthalmic device 1 according to the first embodiment. Figure 3 schematically represents the irradiation area IP of the slit-shaped illumination light irradiated onto the fundus Ef and the virtual aperture range OP on the light-receiving surface SR of the image sensor 51.

[0081] For example, the control unit 100, described later, uses the optical scanner 30 to deflect the slit-shaped illumination light formed by the illumination optical system 20. As a result, the illumination area IP of the slit-shaped illumination light in the fundus Ef, which is the imaging site, is sequentially moved (shifted) in a direction perpendicular to the slit direction (e.g., the horizontal direction) (e.g., the vertical direction).

[0082] On the light-receiving surface SR of the image sensor 51, for example, the position of the aperture range OP that is the target for capturing the light-receiving result of the return light from the fundus Ef is changed by the control unit 100, which will be described later. At this time, the position (or position and shape) of the aperture range OP is set according to the position of the illumination area IP of the illumination light in the fundus Ef. Specifically, the control unit 100, which will be described later, controls the optical scanner 30 and the image sensor 51 so that the illumination area IP' on the light-receiving surface SR, which corresponds to the illumination area IP of the illumination light in the fundus Ef, overlaps with the aperture range OP. In other words, the control unit 100, which will be described later, controls the optical scanner 30 and the image sensor 51 so that the illumination area IP of the illumination light in the fundus Ef overlaps with the target area for aperture in the fundus Ef, which corresponds to the aperture range OP on the light-receiving surface SR. It is desirable that the aperture range OP is a range that matches the illumination area IP' of the return light of the illumination light on the light-receiving surface SR, or a range that is wider than the illumination area IP'. For example, the control unit 100, described later, performs movement control of the aperture range OP for the image sensor 51 in synchronization with the movement control of the illumination area IP for the optical scanner 30. This makes it possible to acquire high-quality images of the fundus Ef with strong contrast in a simple configuration without being affected by unwanted scattered light.

[0083] In Figure 3, the control unit 100, described later, moves the irradiation area IP' on the light-receiving surface SR by controlling the optical scanner 30. The control unit 100, described later, moves the aperture range OP so that it overlaps with the irradiation area IP' by controlling the image sensor 51 in conjunction with the movement of the irradiation area IP'. In some embodiments, the control unit 100, described later, moves the aperture range OP by controlling the image sensor 51. The control unit 100, described later, moves the irradiation area in the fundus Ef corresponding to the irradiation area IP' so that the irradiation area IP' overlaps with the aperture range OP so that it overlaps with the aperture range OP.

[0084] [Control system configuration] Figure 4 shows a block diagram of an example configuration of the control system (processing system) of the ophthalmic device 1 according to the first embodiment.

[0085] The control system of the ophthalmic device 1 is centered around the control unit 100. At least a portion of the control system's configuration may be included within the ophthalmic device 1.

[0086] (Control unit 100) The control unit 100 controls each part of the ophthalmic device 1. The control unit 100 includes a main control unit 101 and a storage unit 102. The main control unit 101 includes a processor and performs control processing for each part of the ophthalmic device 1 by executing processing according to the program stored in the storage unit 102.

[0087] (Main control unit 101) The main control unit 101 controls the light source 10, the moving mechanism 10D, the illumination optical system 20, the optical scanner 30, the imaging optical system 40, the imaging device 50, and the data processing unit 200.

[0088] Control of the light source 10 includes switching the light source on and off (or the wavelength range of light), controlling the lighting time, and controlling the light intensity of the light source.

[0089] The moving mechanism 10D changes at least one of the position and orientation of the light source 10 by a known mechanism. The main control unit 101 can change at least one of the relative position and relative orientation of the light source 10 with respect to the iris diaphragm 21 and the slit 22.

[0090] Control of the illumination optical system 20 includes control of the moving mechanism 22D. The moving mechanism 22D moves the slit 22 in the direction of the optical axis of the illumination optical system 20. The main control unit 101 controls the moving mechanism 22D according to the state of the eye under examination E, thereby positioning the slit 22 to a position corresponding to the state of the eye under examination E. The state of the eye under examination E includes the shape of the fundus Ef, refractive power, and axial length. Refractive power can be obtained from a known refractive power measuring device, such as those disclosed in Japanese Patent Publication No. 61-293430 or Japanese Patent Publication No. 2010-259495. Axial length can be obtained from a known axial length measuring device or from measurements taken with an optical coherence tomography (OCT).

[0091] For example, first control information, in which the position of the slit 22 on the optical axis of the illumination optical system 20 is pre-associated with the refractive index, is stored in the storage unit 102. The main control unit 101 refers to the first control information to identify the position of the slit 22 corresponding to the refractive index, and controls the movement mechanism 22D so that the slit 22 is positioned at the identified location.

[0092] Here, as the slit 22 moves, the light intensity distribution of the light passing through the opening formed in the slit 22 changes. At this time, as described above, the main control unit 101 can change the position and orientation of the light source 10 by controlling the movement mechanism 10D.

[0093] In some embodiments, the main control unit 101 modifies at least one of the shape, position, and size of the opening formed in the slit 22.

[0094] Control of the optical scanner 30 includes controlling the angle of the deflection plane that deflects the illumination light. By controlling the angular range of the deflection plane, it is possible to control the scan range (scan start position and scan end position). By controlling the rate at which the angle of the deflection plane changes, it is possible to control the scan speed.

[0095] In some embodiments, the main control unit 101 controls the optical scanner 30 so that it scans the illumination area in the fundus Ef with illumination light when the deflection angle of the deflection plane of the optical scanner 30 is at a predetermined deflection angle.

[0096] In some embodiments, the main control unit 101 deflects the slit-shaped illumination light by controlling the optical scanner 30, thereby changing the position (or position and shape) of the illumination area in the fundus Ef. In some embodiments, the main control unit 101 changes the position (or position and shape) of the illumination area in the fundus Ef by changing at least one of the shape, position, and size of the opening formed in the slit 22. In some embodiments, the main control unit 101 changes the position (or position and shape) of the illumination area in the fundus Ef by controlling the slit 22 and the optical scanner 30 as described above.

[0097] In some embodiments, the main control unit 101 changes the irradiation time of the illumination light to the fundus Ef by controlling at least one of the light source 10 and the optical scanner 30.

[0098] Control of the imaging optical system 40 includes control of the movement mechanism 47D. The movement mechanism 47D moves the focusing lens 47 in the optical axis direction of the imaging optical system 40. The main control unit 101 can control the movement mechanism 47D based on the analysis results of the image acquired using the image sensor 51. The main control unit 101 can also control the movement mechanism 47D based on user operations using the operation unit 110, which will be described later.

[0099] Control of the imaging device 50 includes control of the image sensor 51. Control of the image sensor 51 includes setting the aperture range on the light-receiving surface and control for reading out the light-receiving results using a global shutter method.

[0100] The main control unit 101 changes the position (or arrangement and shape) of the aperture range on the light-receiving surface of the image sensor 51 in synchronization with the movement of the illumination area of ​​the illumination light in the fundus Ef.

[0101] In some embodiments, the main control unit 101 identifies the position of the illumination area of ​​the illuminating light in the fundus Ef based on the deflection angle of the optical scanner 30, and controls the illumination area or the aperture range of the image sensor 51 based on the identified position. In this case, the position or size (width) of the illumination area (illumination range) or aperture range, the illumination time of the illuminating light, or the aperture time of the aperture range is changed. The deflection angle of the optical scanner 30 can be determined based on detection results obtained by a separately provided angle detector, or based on a signal from the optical scanner 30 indicating the deflection state.

[0102] In some embodiments, the main control unit 101 executes control corresponding to the control content for each range on the optical scanner 30 and the image sensor 51 based on sequence information representing the control content for each range obtained by dividing a predetermined deflection angle range of the optical scanner 30.

[0103] The control of the data processing unit 200 includes various image processing and analysis processes for the light reception results acquired from the image sensor 51. Image processing includes noise reduction processing for the light reception results and brightness correction processing to make it easier to identify predetermined parts depicted in the light reception image based on the light reception results. Analysis processing includes processes for determining the focus state.

[0104] The data processing unit 200 can form a light-receiving image corresponding to the aperture range based on the light-receiving results read from the image sensor 51 using a global shutter method. As an image forming unit, the data processing unit 200 can sequentially form light-receiving images corresponding to the aperture range and form an image of the eye E under examination from the multiple light-receiving images formed.

[0105] The data processing unit 200 includes a processor and performs processing according to a program stored in a memory unit or the like to realize the above functions.

[0106] In some embodiments, the light source 10 includes two or more light sources. In this case, each of the two or more light sources is provided corresponding to two or more openings formed in the iris diaphragm 21. The main control unit 101 can change at least one of the position and orientation (orientation in the direction in which the light intensity distribution is maximized) of each light source by controlling a moving mechanism provided corresponding to each of the two or more light sources.

[0107] (Storage unit 102) The memory unit 102 stores various computer programs and data. The computer programs include calculation programs and control programs for controlling the ophthalmic device 1.

[0108] (Operation unit 110) The operation unit 110 includes an operating device or an input device. The operation unit 110 includes buttons and switches (e.g., operating handles, operating knobs, etc.) and operating devices (mouse, keyboard, etc.) provided on the ophthalmic device 1. The operation unit 110 may also include any operating device or input device such as a trackball, operating panel, switches, buttons, dials, etc.

[0109] (Display section 120) The display unit 120 displays an image of the eye E being examined, generated by the data processing unit 200. The display unit 120 includes a display device such as a flat panel display like an LCD (Liquid Crystal Display). The display unit 120 may also include various display devices such as a touch panel provided on the housing of the ophthalmic device 1.

[0110] The operation unit 110 and the display unit 120 do not necessarily need to be configured as separate devices. For example, a device that integrates display and operation functions, such as a touch panel, can be used. In that case, the operation unit 110 is configured to include this touch panel and a computer program. The operations performed on the operation unit 110 are input to the control unit 100 as electrical signals. Alternatively, operations and information input may be performed using a graphical user interface (GUI) displayed on the display unit 120 and the operation unit 110. In some embodiments, the functions of the display unit 120 and the operation unit 110 are realized by a touchscreen.

[0111] (Other configurations) In some embodiments, the ophthalmic apparatus 1 further includes a fixation projection system. For example, the optical path of the fixation projection system is coupled to the optical path of the imaging optical system 40 in the optical system configuration shown in Figure 1. The fixation projection system can present an internal or external fixation target to the eye under examination E. When presenting an internal fixation target to the eye under examination E, the fixation projection system includes an LCD that displays the internal fixation target under control from the control unit 100, and projects the fixation light beam output from the LCD onto the fundus of the eye under examination E. The LCD is configured to allow the display position of the fixation target on its screen to be changed. By changing the display position of the fixation target on the LCD, it is possible to change the projection position of the fixation target on the fundus of the eye under examination E. The display position of the fixation target on the LCD can be specified by the user using the operation unit 110.

[0112] In some embodiments, the ophthalmic device 1 includes an alignment system. In some embodiments, the alignment system includes an XY alignment system and a Z alignment system. The XY alignment system is used to align the device optical system and the eye under examination E in a direction intersecting the optical axis of the device optical system (objective lens 46). The Z alignment system is used to align the device optical system and the eye under examination E in the direction of the optical axis of the ophthalmic device 1 (objective lens 46).

[0113] For example, the XY alignment system projects a bright spot (a bright spot in the infrared or near-infrared region) onto the eye E under examination. The data processing unit 200 acquires an anterior segment image of the eye E on which the bright spot is projected, and determines the displacement between the bright spot image depicted in the acquired anterior segment image and the alignment reference position. The control unit 100 moves the device optical system and the eye E under examination relative to each other in a direction intersecting the optical axis direction using a moving mechanism (not shown) so that the determined displacement is canceled out.

[0114] For example, the Z-alignment system projects alignment light in the infrared or near-infrared region from a position off-axis from the optical axis of the device's optical system and receives the alignment light reflected by the anterior segment of the eye E under examination. The data processing unit 200 determines the distance of the eye E under examination relative to the device's optical system from the receiving position of the alignment light, which changes according to the distance of the eye E to the device's optical system. The control unit 100 moves the device's optical system and the eye E under examination relative to the optical axis in the direction of the optical axis using a moving mechanism (not shown) so that the determined distance becomes the desired working distance.

[0115] In some embodiments, the alignment system function is realized by two or more anterior segment cameras positioned off-axis from the optical axis of the device optical system. For example, as disclosed in Japanese Patent Application Publication No. 2013-248376, the data processing unit 200 analyzes the anterior segment image of the eye under examination E acquired substantially simultaneously by two or more anterior segment cameras and determines the three-dimensional position of the eye under examination E using known trigonometry. The control unit 100 moves the device optical system and the eye under examination E three-dimensionally relative to each other using a moving mechanism (not shown) such that the optical axis of the device optical system substantially coincides with the axis of the eye under examination E and the distance of the device optical system to the eye under examination E is a predetermined working distance.

[0116] As described above, in the ophthalmic device 1, the slit 22 (aperture), the imaging site (fundus Ef), and the image sensor 51 (light-receiving surface) are positioned in approximately optically conjugate positions. The ophthalmic device 1 moves in conjunction with the illumination range and aperture range of the light-receiving surface of the image sensor 51, which correspond to the illumination area of ​​the illumination light in the fundus Ef. In other words, the ophthalmic device 1 moves in conjunction with the illumination area of ​​the illumination light in the fundus Ef and the target area of ​​aperture in the fundus Ef, which corresponds to the aperture range of the light-receiving surface of the image sensor 51. This makes it possible to acquire a clear image of the imaging site while suppressing the effects of unwanted scattered light.

[0117] The data processing unit 200 is an example of an "image forming unit" according to this embodiment.

[0118] [Operation] Next, the operation of the ophthalmic device 1 will be explained. In the following example of operation, it is assumed that alignment has been completed and that the slit 22 has been moved according to the refractive power of the eye E being examined. Furthermore, in the following explanation, the imaging area (fundus imaging target area) will be described using a deflection angle range of ±22.5° relative to the scan center as an example, but a deflection angle range wider than ±22.5° or narrower than ±22.5° may also be used.

[0119] (Example of first action) Figure 5A shows an explanatory diagram of a first operation example of the ophthalmic device 1 according to the first embodiment. In Figure 5A, the vertical axis represents the deflection angle range (±22.5°) with respect to the scan center as the imaging area (fundus imaging target area) in the fundus Ef, and the horizontal axis represents the time axis. The position where the deflection angle is 0° corresponds to the position where the optical axis of the illumination optical system 20 (imaging optical system 40) intersects with the fundus Ef after alignment is completed.

[0120] In the first operational example, during the one-frame period in which the image sensor 51 captures the light reception result of the aperture range, the target area for aperture in the fundus Ef corresponding to the aperture range is captured in the shooting area R. IMG To cover the entire area, the shooting region R IMGThe area is illuminated with slit-shaped illumination light. For example, one frame period corresponds to the sum of the aperture time for which the aperture range is open and the data transmission time for transmitting the light reception result of the aperture range. Specifically, the control unit 100 captures the image area R in the range of +22.5° to -22.5° in the fundus Ef. IMG The optical scanner 30 is controlled so that the illumination area of ​​the lighting light scans (moves) at a constant speed.

[0121] In the image sensor 51, the shooting area RIMG As the internal illumination area moves, the aperture range, which has a predetermined aperture width and remains open for a predetermined time, is sequentially moved. Specifically, the control unit 100 sequentially controls the image sensor 51 so that the aperture range, which has an aperture width Wd1, remains open for a predetermined time so as to overlap with the illumination area ILR1 on the light-receiving surface corresponding to the illumination area of ​​the illumination light in the fundus Ef.

[0122] Here, since the distance between the ophthalmic device 1 and the eye under examination during imaging, and the optical magnification of the optical system of the ophthalmic device 1 are known, the imaging area RIMG The position of the object to be photographed can be determined from the deflection angle of the optical scanner 30. That is, the control unit 100 that controls the optical scanner 30 can determine the position of the object to be photographed and the position of the illumination range ILR1 on the light-receiving surface, which corresponds to the deflection angle of the optical scanner 30.

[0123] For example, when the deflection angle range is DR1 (= +22.5° to +(22.5-f(Wd1))°), the control unit 100 sets the image sensor 51 so that an aperture range OR1 with an aperture width Wd1 is open for a predetermined opening time at the position of the light-receiving surface corresponding to the deflection angle range DR1. Here, f(Wd1) corresponds to the deflection angle of the optical scanner 30 when it is deflected in the direction of 0° by a distance corresponding to the aperture width Wd1 on the light-receiving surface from the position of the target area corresponding to the deflection angle of 22.5°.

[0124] Similarly, when the deflection angle range is DR2 (=(22.5-f(Wd1))°~(22.5-f(Wd1×2)), the control unit 100 sets the image sensor 51 so that an aperture range OR2 having an aperture width Wd1 is open for a predetermined aperture time at the position of the light-receiving surface corresponding to the deflection angle range DR2.

[0125] The control unit 100 reads out the light reception results obtained from the light-receiving elements in aperture range OR1 using a global shutter method. The control unit 100 uses the light reception results obtained from the light-receiving elements in the range that overlaps with the illumination range ILR1 from the read-out light reception results to cause the data processing unit 200 to form a one-frame image of the fundus Ef.

[0126] According to the first example of operation of the first embodiment, the aperture range on the light-receiving surface of the image sensor 51, which can read out the light-receiving result using a global shutter method, can be moved in accordance with the illumination area of ​​the illumination light in the fundus Ef. This makes it possible to acquire a clear image of the shooting area while suppressing the effects of unwanted scattered light, using a simple configuration with an image sensor that can read out the light-receiving result using a global shutter method.

[0127] In the first embodiment, the frame period is the image acquisition period T. IMG This is equivalent to shortening the image acquisition period. Therefore, high-quality images of the fundus Ef can be obtained while reducing the burden on the eye being examined.

[0128] (Example of second action) Figure 5B shows an explanatory diagram of a second operation example of the ophthalmic device 1 according to the first embodiment. In Figure 5B, as in Figure 5A, the vertical axis represents the deflection angle range (±22.5°) relative to the scan center as the imaging area in the fundus Ef, and the horizontal axis represents the time axis.

[0129] In the second operation example, an aperture range with different aperture widths is set according to the illumination range of the illumination light. In this case, the control unit 100 sets the imaging area R in the range of +22.5° to -22.5° in the fundus Ef. IMG The shooting area R IMGThe light scanner 30 is controlled such that the irradiation area of the illumination light scans (moves) at a deflection speed (scanning speed) corresponding to the position of . Also, the control unit 100 sequentially controls the image sensor 51 so that an aperture range having a desired aperture width opens for a predetermined aperture time so as to overlap with the irradiation range ILR11 on the light-receiving surface corresponding to the irradiation area of the illumination light on the fundus Ef.

[0130] For example, when the deflection angle range is the above DR1, the control unit 100 controls the light scanner 30 to deflect the illumination light at a deflection speed corresponding to the deflection angle range DR1. Further, the control unit 100 controls the image sensor 51 so that an aperture range having an aperture width Wd1 opens for a predetermined aperture time at the position of the light-receiving surface corresponding to the deflection angle range DR1.

[0131] For example, when the deflection angle range is the above DR2, the control unit 100 controls the light scanner 30 to deflect the illumination light at a deflection speed corresponding to the deflection angle range DR2. Further, the control unit 100 controls the image sensor 51 so that an aperture range having an aperture width Wd2 opens for a predetermined aperture time at the position of the light-receiving surface corresponding to the deflection angle range DR2.

[0132] Hereinafter, the control of the light scanner 30 and the image sensor 51 is similarly repeated, and when the scanning of the imaging area R on the fundus Ef with the illumination light is completed, the control unit 100 reads out the light-receiving result obtained by the light-receiving elements of the aperture range OR11 in the global shutter method. The control unit 100 causes the data processing unit 200 to form an image of one frame of the fundus Ef using the light-receiving results obtained by the light-receiving elements in the range overlapping with the irradiation range ILR11 among the read light-receiving results. IMG

[0133] For example, the memory unit 102 stores second control information in which the deflection speed of the optical scanner 30 and the aperture width of the aperture range are pre-associated with the deflection angle range (position of the target to be photographed). The control unit 100 can refer to the second control information to control the optical scanner 30 so as to deflect the illumination light at a deflection speed corresponding to the position of the target to be photographed, and to control the image sensor 51 so as to set an aperture range having an aperture width corresponding to the position of the target to be photographed.

[0134] As described above, the control unit 100 controls the optical scanner 30 to deflect the illumination light at a deflection speed corresponding to the position of the illumination area in the fundus Ef, and controls the image sensor 51 to set an aperture range having an aperture width corresponding to the position of the illumination area. In some embodiments, aperture ranges that open at different aperture times are set depending on the position of the illumination area in the fundus Ef.

[0135] According to the second operation example of the first embodiment, the aperture range on the light-receiving surface of the image sensor 51, which can read out the light-receiving result using a global shutter method, can be moved in accordance with the illumination area of ​​the illumination light in the fundus Ef. At this time, since the aperture range can be set sequentially so that the aperture width is different, the movement speed (scan speed) of the illumination area in the fundus Ef can be changed. This means that the amount of illumination light can be adjusted according to the position of the target of imaging. As a result, the entire imaging area can be illuminated with a uniform amount of light without reducing the amount of illumination light at positions far from the center of the imaging area (for example, positions with a large deflection angle). Therefore, it becomes possible to acquire higher quality images of the fundus Ef.

[0136] <Second Embodiment> In the second embodiment, for each frame period in which the image sensor 31 captures the light reception result of the aperture range, the area of ​​illumination light in the fundus Ef or the area of ​​aperture target in the fundus Ef corresponding to the aperture range is changed, and the area of ​​aperture target is the shooting area R for two or more frame periods. IMG The optical scanner 30 and the image sensor 51 are controlled to cover the entire area.

[0137] The following description will focus on the differences between the ophthalmic apparatus according to the second embodiment and the ophthalmic apparatus according to the first embodiment.

[0138] The configuration of the optical system and the control system of the ophthalmic apparatus according to the second embodiment are the same as the configuration of the optical system and the control system of the ophthalmic apparatus 1 according to the first embodiment.

[0139] (Example of first action) Figure 6A shows an explanatory diagram of the first operation example of the ophthalmic device according to the second embodiment. In Figure 6A, as in Figure 5A, the vertical axis represents the deflection angle range (±22.5°) relative to the scan center as the imaging area in fundus Ef, and the horizontal axis represents the time axis.

[0140] In the first operational example, the illumination range on the light-receiving surface is changed for each frame period during which the image sensor 51 captures the light-receiving result of the aperture range, and the aperture range is changed so as to overlap with the changed illumination range. Specifically, the control unit 100 scans (moves) the illumination area of ​​the illumination light at a constant speed for each predetermined range obtained by dividing the fundus Ef from +22.5° to -22.5°, and the illumination area of ​​the illumination light covers the imaging area R over two or more frames. IMG The optical scanner 30 is controlled to cover the area.

[0141] In the image sensor 51, the shooting area RIMG As the internal illumination area moves, the aperture range, which has a predetermined aperture width and remains open for a predetermined time, is sequentially moved. Specifically, the control unit 100 sequentially controls the image sensor 51 so that the aperture range, which has an aperture width Wd1, remains open for a predetermined time so as to overlap with the illumination area ILR1 on the light-receiving surface corresponding to the illumination area of ​​the illumination light in the fundus Ef.

[0142] For example, when the deflection angle range is DR1 as described above, the control unit 100 controls the optical scanner 30 to illuminate the target area corresponding to the deflection angle range DR1 with illumination light. Furthermore, the control unit 100 controls the image sensor 51 to set the aperture range OR21 to overlap with the illumination range ILR21 on the light-receiving surface corresponding to the illumination area of ​​the illumination light. In other words, the control unit 100 controls the optical scanner 30 to illuminate the target area corresponding to the deflection angle range DR1 with illumination light, and controls the image sensor 51 to open an aperture range having an aperture width Wd1 at the position of the light-receiving surface corresponding to the deflection angle range DR1 for a predetermined opening time.

[0143] Similarly, for example, when the deflection angle range is DR2 as described above, the control unit 100 controls the optical scanner 30 to illuminate the target area corresponding to the deflection angle range DR2 with illumination light. Furthermore, the control unit 100 controls the image sensor 51 to set the aperture range OR22 to overlap with the illumination range ILR22 on the light-receiving surface corresponding to the illumination area of ​​the illumination light. In other words, the control unit 100 controls the optical scanner 30 to illuminate the target area corresponding to the deflection angle range DR2 with illumination light, and controls the image sensor 51 to open an aperture range having an aperture width Wd1 at the position of the light-receiving surface corresponding to the deflection angle range DR2 for a predetermined opening time.

[0144] Similarly, for example, when the deflection angle range is DR3 as described above, the control unit 100 controls the optical scanner 30 to illuminate the target area corresponding to the deflection angle range DR3 with illumination light. Furthermore, the control unit 100 controls the image sensor 51 to set the aperture range OR23 to overlap with the illumination range ILR23 on the light-receiving surface corresponding to the illumination area of ​​the illumination light. In other words, the control unit 100 controls the optical scanner 30 to illuminate the target area corresponding to the deflection angle range DR3 with illumination light, and controls the image sensor 51 to open an aperture range having an aperture width Wd1 at the position of the light-receiving surface corresponding to the deflection angle range DR3 for a predetermined opening time.

[0145] The control unit 100 reads out the light reception results obtained by the photodetectors in the aperture range OR21 within the deflection angle range DR1 using a global shutter method, and uses the light reception results obtained by the photodetectors in the range that overlaps with the illumination range ILR21 to cause the data processing unit 200 to form an image of the fundus Ef.

[0146] Similarly, the control unit 100 reads out the light reception results obtained by the photodetectors in the aperture range OR22 (OR23) within the deflection angle range DR2 (DR3) using a global shutter method, and uses the light reception results obtained by the photodetectors in the range that overlaps with the illumination range ILR22 (ILR23) from the read-out light reception results to cause the data processing unit 200 to form an image of the fundus Ef.

[0147] The image formation for each of the above frames may be performed in parallel with the reception of light for other frames.

[0148] The control of the optical scanner 30 and image sensor 51 is repeated in the same manner, and the imaging area R in the fundus Ef is illuminated by the illumination light. IMG Once the irradiation (scanning) is complete, the control unit 100 synthesizes the images formed for each frame to create the imaging area R IMG The data processing unit 200 is instructed to create an image of the entire fundus Ef, which is depicted in detail.

[0149] According to the first operation example of the second embodiment, for each frame period, the aperture range on the light-receiving surface of the image sensor 51, which can read out the light-receiving result using a global shutter method, can be moved to match the illumination area of ​​the illumination light in the fundus Ef. In this case, the second embodiment has a different image acquisition period T compared to the first embodiment. IMG This shortens the processing time. As a result, it becomes possible to acquire clear images of the area being photographed using a simple configuration with an image sensor that can read out the light reception results using a global shutter method, while suppressing the effects of unwanted scattered light as well as the effects of fixation micro-movements of the eye being examined.

[0150] (Example of second action) Figure 6B shows an explanatory diagram of a second operational example of the ophthalmic device according to the second embodiment. Similar to Figure 6A, the vertical axis of Figure 6B represents the deflection angle range (±22.5°) relative to the scan center as the imaging area in fundus Ef, and the horizontal axis represents the time axis.

[0151] In the second operation example, for each frame period, an aperture range with a different aperture width is set according to the illumination range of the illumination light. In this case, the control unit 100 sets the imaging area R in the range of +22.5° to -22.5° in the fundus Ef for each frame period. IMG The shooting area R IMG The optical scanner 30 is controlled so that the illumination area of ​​the illumination light scans (moves) at a deflection speed (scanning speed) corresponding to the position. The control unit 100 also sequentially controls the image sensor 51 so that, for each frame period, an aperture range with a desired aperture width is opened for a predetermined aperture time so as to overlap with the illumination range on the light-receiving surface corresponding to the illumination area of ​​the illumination light in the fundus Ef.

[0152] For example, when the deflection angle range is DR1, the control unit 100 controls the optical scanner to deflect the illumination light at a deflection speed corresponding to the deflection angle range DR1. Furthermore, the control unit 100 controls the image sensor 51 so that the aperture range OR31, which has an aperture width Wd1, is open for a predetermined aperture time so as to overlap with the illumination range ILR31 on the light-receiving surface corresponding to the illumination area of ​​the illumination light in the fundus Ef.

[0153] For example, when the deflection angle range is DR2, the control unit 100 controls the optical scanner to deflect the illumination light at a deflection speed corresponding to the deflection angle range DR2. Furthermore, the control unit 100 controls the image sensor 51 so that the aperture range OR32, which has an aperture width Wd2, is open for a predetermined aperture time so as to overlap with the illumination range ILR32 on the light-receiving surface corresponding to the illumination area of ​​the illumination light in the fundus Ef.

[0154] Similarly, for example, when the deflection angle range is DR3, the control unit 100 controls the optical scanner to deflect the illumination light at a deflection speed corresponding to the deflection angle range DR3. Furthermore, the control unit 100 controls the image sensor 51 so that the aperture range OR33, which has an aperture width Wd3 (not shown) and overlaps with the illumination range ILR33 on the light-receiving surface corresponding to the illumination area of ​​the illumination light in the fundus Ef, is open for a predetermined aperture time.

[0155] The control unit 100 reads out the light reception results obtained from the light-receiving elements in the aperture range OR31, OR32, OR33, ... using a global shutter method, and uses the light reception results obtained from the light-receiving elements in the range that overlaps with the illumination range to cause the data processing unit 200 to form an image of the fundus Ef. The formation of the image for each frame may be performed in parallel with the light reception of other frames.

[0156] The control of the optical scanner 30 and image sensor 51 is repeated in the same manner, and the imaging area R in the fundus Ef is illuminated by the illumination light. IMG Once the irradiation (scanning) is complete, the control unit 100 synthesizes the images formed for each frame to create the imaging area R IMG The data processing unit 200 is instructed to create an image of the entire fundus Ef, which is depicted in detail.

[0157] For example, the memory unit 102 stores third control information in which the deflection speed of the optical scanner 30 and the aperture width of the aperture range are pre-associated with the deflection angle range (position of the target to be photographed). The control unit 100 can refer to the third control information to control the optical scanner 30 so as to deflect the illumination light at a deflection speed corresponding to the position of the target to be photographed, and to control the image sensor 51 so as to set an aperture range having an aperture width corresponding to the position of the target to be photographed.

[0158] As described above, the control unit 100 controls the optical scanner 30 to deflect the illumination light at a deflection speed corresponding to the position of the illumination area in the fundus Ef for each frame period, and controls the image sensor 51 to set an aperture range having an aperture width corresponding to the position of the illumination area. In some embodiments, aperture ranges that open at different aperture times are set depending on the position of the illumination area in the fundus Ef.

[0159] According to the second operation example of the second embodiment, the aperture range on the light-receiving surface of the image sensor 51, which can read out the light-receiving result using a global shutter method, can be moved in accordance with the illumination area of ​​the illumination light in the fundus Ef. At this time, since the aperture range can be set sequentially so that the aperture width is different, the movement speed (scan speed) of the illumination area in the fundus Ef can be changed. This means that the amount of illumination light can be adjusted according to the position of the target of imaging. As a result, the entire imaging area can be illuminated with a uniform amount of light without reducing the amount of illumination light at positions far from the center of the imaging area (for example, positions with a large deflection angle). Therefore, it becomes possible to acquire higher quality images of the fundus Ef.

[0160] <Third Embodiment> In the third embodiment, for each frame period in which the image sensor 31 captures the light reception result of the aperture range, the area of ​​illumination light in the fundus Ef or the area of ​​aperture target in the fundus Ef corresponding to the aperture range is changed, and the area of ​​aperture target is the shooting area R for two or more frame periods. IMG The optical scanner 30 and the image sensor 51 are controlled to cover the area. The difference between the third embodiment and the second embodiment is that the optical scanner 30 and the image sensor 51 are controlled so that the illumination range of the illumination light on the light-receiving surface of the image sensor 51 matches the aperture range.

[0161] The following description will focus on the differences between the ophthalmic apparatus according to the third embodiment and the ophthalmic apparatus according to the second embodiment.

[0162] The configuration of the optical system and the control system of the ophthalmic apparatus according to the third embodiment are the same as the configuration of the optical system and the control system of the ophthalmic apparatus according to the second embodiment (i.e., the ophthalmic apparatus 1 according to the first embodiment).

[0163] (Example of first action) Figure 7A shows an explanatory diagram of the first operation example of the ophthalmic device according to the third embodiment. In Figure 7A, as in Figure 6A, the vertical axis represents the deflection angle range (±22.5°) relative to the scan center as the imaging area in fundus Ef, and the horizontal axis represents the time axis.

[0164] In the first operational example, the illumination range on the light-receiving surface is changed for each frame period during which the image sensor 51 captures the light-receiving result of the aperture range, and the aperture range is changed to match the changed illumination range (position of the illumination range, or position and shape of the illumination range). Specifically, the control unit 100 illuminates a fixed illumination area with illumination light for each predetermined range obtained by dividing the +22.5° to -22.5° range in the fundus Ef, and the illumination area of ​​the illumination light covers the imaging area R for two or more frames. IMG The optical scanner 30 is controlled to cover the area.

[0165] The image sensor 51 changes the shooting area for each frame. RIMG The aperture range, which has a predetermined aperture width and remains open for a predetermined time, is sequentially moved to match the position of the internal illumination area. Specifically, the control unit 100 sequentially controls the image sensor 51 so that an aperture range having an aperture width Wd1 that matches the illumination area on the light-receiving surface corresponding to the illumination area of ​​the illumination light in the fundus Ef is opened for a predetermined time.

[0166] For example, when the deflection angle range is DR1 as described above, the control unit 100 controls the optical scanner 30 to illuminate (scan) the target area corresponding to the deflection angle range DR1 with illumination light. Furthermore, the control unit 100 controls the image sensor 51 to set the aperture range OR41 to match the illumination range IL41 on the light-receiving surface corresponding to the illumination area of ​​the illumination light. In other words, the control unit 100 controls the optical scanner 30 to illuminate the target area corresponding to the deflection angle range DR1 with illumination light, and controls the image sensor 51 so that the aperture range OR41 having an aperture width Wd1 opens for a predetermined opening time at the position of the light-receiving surface corresponding to the deflection angle range DR1.

[0167] For example, when the deflection angle range is DR2 as described above, the control unit 100 controls the optical scanner 30 to illuminate the target area corresponding to the deflection angle range DR2 with illumination light. Furthermore, the control unit 100 controls the image sensor 51 to set the aperture range OR42 to match the illumination range ILR42 on the light-receiving surface corresponding to the illumination area of ​​the illumination light. In other words, the control unit 100 controls the optical scanner 30 to illuminate the target area corresponding to the deflection angle range DR2 with illumination light, and controls the image sensor 51 so that the aperture range OR42 having an aperture width Wd1 opens for a predetermined opening time at the position of the light-receiving surface corresponding to the deflection angle range DR2.

[0168] Similarly, for example, when the deflection angle range is DR3 as described above, the control unit 100 controls the optical scanner 30 to illuminate the target area corresponding to the deflection angle range DR3 with illumination light. Furthermore, the control unit 100 controls the image sensor 51 to set the aperture range OR43 to overlap with the illumination range ILR43 on the light-receiving surface corresponding to the illumination area of ​​the illumination light. In other words, the control unit 100 controls the optical scanner 30 to illuminate the target area corresponding to the deflection angle range DR3 with illumination light, and controls the image sensor 51 to open the aperture range OR43, which has an aperture width Wd1, at the position of the light-receiving surface corresponding to the deflection angle range DR3 for a predetermined opening time.

[0169] The control unit 100 reads out the light reception results obtained by the light receiving element with aperture range OR41 in the deflection angle range DR1 using a global shutter method, and uses the read-out light reception results to cause the data processing unit 200 to form an image of the fundus Ef.

[0170] Similarly, the control unit 100 reads out the light reception results obtained by the photodetector in aperture range OR42 (OR43) within the deflection angle range DR2 (DR3) using a global shutter method, and uses the read-out light reception results to cause the data processing unit 200 to form an image of the fundus Ef. The formation of the image for each frame may be performed in parallel with the light reception of other frames.

[0171] The control of the optical scanner 30 and image sensor 51 is repeated in the same manner, and the imaging area R in the fundus Ef is illuminated by the illumination light. IMG Once the irradiation (scanning) is complete, the control unit 100 synthesizes the images formed for each frame to create the imaging area R IMG The data processing unit 200 is instructed to create an image of the entire fundus Ef, which is depicted in detail.

[0172] According to the first operation example of the third embodiment, the aperture range on the light-receiving surface of the image sensor 51, which can read out the light-receiving result using a global shutter method, can be moved for each frame period to match the illumination area of ​​the illumination light in the fundus Ef. In this case, since the illumination area and the aperture range coincide in the third embodiment, images can be acquired with simpler processing compared to the second embodiment. As a result, with a simple configuration and processing using an image sensor that can read out the light-receiving result using a global shutter method, it becomes possible to acquire a clear image of the shooting area while suppressing the effects of unwanted scattered light as well as fixation micro-movements of the eye under examination. Furthermore, it becomes possible to eliminate the need for repeated shooting due to fixation micro-movements of the eye under examination, or distortion correction processing due to fixation micro-movements.

[0173] (Example of second action) Figure 7B shows an explanatory diagram of a second operational example of the ophthalmic device according to the third embodiment. Similar to Figure 7A, the vertical axis of Figure 7B represents the deflection angle range (±22.5°) relative to the scan center as the imaging area in fundus Ef, and the horizontal axis represents the time axis.

[0174] In the second operation example, for each frame period, illumination light is emitted for an illumination time corresponding to the illumination area of ​​the fundus Ef, and an aperture range is set that opens for an aperture time corresponding to the illumination area of ​​the fundus Ef. In this case, the control unit 100 sets the imaging area R in the range of +22.5° to -22.5° of the fundus Ef for each frame period. IMG The shooting area R IMG The optical scanner 30 is controlled so that the illumination area of ​​the illumination light scans (moves) at a deflection speed (scanning speed) corresponding to the position. At this time, the illumination time of the illumination light is changed in accordance with the illumination area. The control unit 100 also sequentially controls the image sensor 51 for each frame period so that an aperture range having a predetermined aperture width matches the illumination range on the light-receiving surface corresponding to the illumination area of ​​the illumination light in the fundus Ef and opens for an aperture time corresponding to that illumination area. In other words, the aperture time of the aperture range is set to match the illumination time of the illumination light.

[0175] For example, when the deflection angle range is DR1 as described above, the control unit 100 controls the optical scanner 30 (or the light source 10 and the optical scanner 30) to deflect the illumination light within the range corresponding to the deflection angle range DR1 for an irradiation time Td1 corresponding to the deflection angle range DR1, thereby illuminating the fundus Ef. Furthermore, the control unit 100 controls the image sensor 51 so that an aperture range OR41 having a predetermined aperture width, which matches the irradiation range ILR41 on the light-receiving surface corresponding to the irradiation area of ​​the illumination light in the fundus Ef, is opened for an aperture time Td1.

[0176] For example, when the deflection angle range is DR2 as described above, the control unit 100 controls the optical scanner 30 to deflect the illumination light within the range corresponding to the deflection angle range DR2 for an irradiation time Td2 corresponding to the deflection angle range DR2, thereby illuminating the fundus Ef. Furthermore, the control unit 100 controls the image sensor 51 so that the aperture range OR42, which matches the irradiation range ILR42 on the light-receiving surface corresponding to the irradiation area of ​​the illumination light in the fundus Ef and has a predetermined aperture width, is opened for an aperture time Td2.

[0177] Similarly, for example, when the deflection angle range is DR3 as described above, the control unit 100 controls the optical scanner 30 to deflect the illumination light within the range corresponding to the deflection angle range DR3 for an irradiation time Td3 corresponding to the deflection angle range DR3, thereby illuminating the fundus Ef. Furthermore, the control unit 100 controls the image sensor 51 so that the aperture range OR43, which matches the irradiation range ILR43 on the light-receiving surface corresponding to the irradiation area of ​​the illumination light in the fundus Ef and has a predetermined aperture width, is opened for an aperture time Td3. For example, the imaging area R IMG The closer to the center, the shorter the irradiation time (aperture time).

[0178] The control unit 100 reads out the light reception results obtained from the light-receiving elements in the aperture range OR41, OR42, OR43, OR44, ... using a global shutter method, and uses the read-out light reception results to cause the data processing unit 200 to form an image of the fundus Ef. The formation of the image for each frame may be performed in parallel with the light reception of other frames.

[0179] The control of the optical scanner 30 and image sensor 51 is repeated in the same manner, and the imaging area R in the fundus Ef is illuminated by the illumination light. IMG Once the irradiation (scanning) is complete, the control unit 100 synthesizes the images formed for each frame to create the imaging area R IMG The data processing unit 200 is instructed to create an image of the entire fundus Ef, which is depicted in detail.

[0180] For example, the memory unit 102 stores fourth control information in which the illumination time (aperture time of the aperture range) is pre-associated with the deflection angle range (position of the target to be photographed). The control unit 100 can refer to the fourth control information and control the optical scanner 30 to illuminate the illumination area with illumination light for the illumination time corresponding to the position of the target to be photographed, and control the image sensor 51 to set an aperture range having a predetermined aperture width for the aperture time corresponding to the position of the target to be photographed.

[0181] As described above, the control unit 100 controls the optical scanner 30 so that the illumination light illuminates the illumination area in the fundus Ef for an illumination time corresponding to the position of the illumination area in the fundus Ef for each frame period, and controls the image sensor 51 to set an aperture range that opens for an aperture time corresponding to the position of the illumination area. In some embodiments, an aperture range with different aperture widths is set depending on the position of the illumination area in the fundus Ef.

[0182] According to the second operation example of the third embodiment, the aperture range on the light-receiving surface of the image sensor 51, which can read out the light-receiving results using a global shutter method, can be moved while changing the illumination time (aperture time) according to the illumination area of ​​the illumination light in the fundus Ef. This makes it possible to adjust the amount of illumination light according to the position of the target of imaging. As a result, the entire imaging area can be illuminated with a uniform amount of light without reducing the amount of illumination light at positions far from the center of the imaging area (for example, positions with a large deflection angle). Therefore, it becomes possible to acquire higher quality images of the fundus Ef.

[0183] <Fourth Embodiment> In the above embodiment, the case in which the light reception result obtained by the image sensor 51 is read out using a global shutter method has been described, but the configuration of the embodiment is not limited thereto. In the fourth embodiment, the light reception result obtained by the image sensor 51 is read out using a rolling shutter method.

[0184] In the fourth embodiment, for each frame period in which the image sensor 31 captures the light reception result of the aperture range, the area of ​​illumination light in the fundus Ef or the area of ​​aperture target in the fundus Ef corresponding to the aperture range is changed, and the area of ​​aperture target is the shooting area R for two or more frame periods. IMG The optical scanner 30 and the image sensor 51 are controlled to cover the entire area. The fourth embodiment differs from the third embodiment in that the light reception result obtained by the image sensor 51 is read out using a rolling shutter method.

[0185] The following description will focus on the differences between the ophthalmic apparatus according to the fourth embodiment and the ophthalmic apparatus according to the third embodiment.

[0186] The configuration of the optical system and the control system of the ophthalmic apparatus according to the fourth embodiment are the same as the configuration of the optical system and the control system of the ophthalmic apparatus according to the third embodiment (i.e., the ophthalmic apparatus 1 according to the first embodiment).

[0187] (Example of first action) Figure 8A shows an explanatory diagram of the first operation example of the ophthalmic device according to the fourth embodiment. In Figure 8A, as in Figure 7A, the vertical axis represents the deflection angle range (±22.5°) relative to the scan center as the imaging area in fundus Ef, and the horizontal axis represents the time axis.

[0188] In the first operational example, the illumination range on the light-receiving surface is changed for each frame period during which the image sensor 51 captures the light-receiving result of the aperture range, and the aperture range is changed so as to overlap with the changed illumination range. Specifically, the control unit 100 illuminates a fixed illumination area with illumination light for each predetermined range obtained by dividing the +22.5° to -22.5° range in the fundus Ef, and the illumination area of ​​the illumination light covers the imaging area R for two or more frames. IMG The optical scanner 30 is controlled to cover the area.

[0189] The image sensor 51 changes the shooting area for each frame. RIMGThe aperture range, which has a predetermined aperture width and remains open for a predetermined time, is sequentially moved to match the position of the internal illumination area. Specifically, the control unit 100 sequentially controls the image sensor 51 so that an aperture range having an aperture width Wd1 that overlaps with the illumination area on the light-receiving surface corresponding to the illumination area of ​​the illumination light in the fundus Ef is opened for a predetermined time.

[0190] For example, when the deflection angle range is DR1 as described above, the control unit 100 controls the optical scanner 30 to illuminate (scan) the target area corresponding to the deflection angle range DR1 with illumination light. Furthermore, the control unit 100 controls the image sensor 51 to set the aperture range OR51 to overlap with the illumination range ILR51 on the light-receiving surface corresponding to the illumination area of ​​the illumination light. In other words, the control unit 100 controls the optical scanner 30 to illuminate the target area corresponding to the deflection angle range DR1 with illumination light, and controls the image sensor 51 so that the aperture range OR51 having an aperture width Wd1 is open for a predetermined opening time at the position of the light-receiving surface corresponding to the deflection angle range DR1.

[0191] For example, when the deflection angle range is DR2 as described above, the control unit 100 controls the optical scanner 30 to illuminate the target area corresponding to the deflection angle range DR2 with illumination light. Furthermore, the control unit 100 controls the image sensor 51 to set the aperture range OR52 so as to overlap with the illumination range ILR52 on the light-receiving surface corresponding to the illumination area of ​​the illumination light.

[0192] Similarly, for example, when the deflection angle range is DR3 as described above, the control unit 100 controls the optical scanner 30 to illuminate the target area corresponding to the deflection angle range DR3 with illumination light. Furthermore, the control unit 100 controls the image sensor 51 to set the aperture range OR53 so as to overlap with the illumination range ILR53 on the light-receiving surface corresponding to the illumination area of ​​the illumination light.

[0193] The control unit 100 reads out the light reception results obtained by the light receiving element with aperture range OR51 in the deflection angle range DR1 using a rolling shutter method, and uses the read-out light reception results to cause the data processing unit 200 to form an image of the fundus Ef.

[0194] Similarly, the control unit 100 reads out the light-receiving results obtained by the light-receiving elements in the aperture range OR52 (OR53) within the deflection angle range DR2 (DR3) using a rolling shutter method, and uses the read-out light-receiving results to cause the data processing unit 200 to form an image of the fundus Ef.

[0195] The control of the optical scanner 30 and image sensor 51 is repeated in the same manner, and the imaging area R in the fundus Ef is illuminated by the illumination light. IMG Once the irradiation (scanning) is complete, the control unit 100 synthesizes the images formed for each frame to create the imaging area R IMG The data processing unit 200 is instructed to create an image of the entire fundus Ef, which is depicted in detail.

[0196] According to the first operation example of the fourth embodiment, the aperture range on the light-receiving surface of the image sensor 51, which can read out the light-receiving result in a rolling shutter manner, can be moved for each frame period to match the illumination area of ​​the illumination light in the fundus Ef. In this case, the same effect as in the third embodiment can be obtained by using an image sensor that can read out the light-receiving result in a global shutter manner.

[0197] (Example of second action) Figure 8B shows an explanatory diagram of a second operational example of the ophthalmic device according to the fourth embodiment. Similar to Figure 8A, the vertical axis of Figure 8B represents the deflection angle range (±22.5°) relative to the scan center as the imaging area in fundus Ef, and the horizontal axis represents the time axis.

[0198] In the second operation example, for each frame period, illumination light is irradiated for an illumination time corresponding to the illumination area of ​​the fundus Ef, and an aperture range is set that opens for an aperture time corresponding to the illumination area of ​​the illumination light. In this case, for each frame period, the control unit 100 controls the optical scanner 30 to irradiate the illumination area with illumination light for an illumination time corresponding to the illumination area of ​​the fundus Ef. The control unit 100 also sequentially controls the image sensor 51 for each frame period so that an aperture range having a predetermined aperture width, which overlaps with the illumination area on the light-receiving surface corresponding to the illumination area of ​​the fundus Ef, opens for an aperture time corresponding to the illumination area.

[0199] For example, when the deflection angle range is DR1 as described above, the control unit 100 controls the optical scanner 30 (or the light source 10 and the optical scanner 30) to deflect the illumination light within the range corresponding to the deflection angle range DR1 for an irradiation time Td1 corresponding to the deflection angle range DR1, thereby illuminating the fundus Ef. Furthermore, the control unit 100 controls the image sensor 51 so that an aperture range OR61, which overlaps with the irradiation range ILR61 on the light-receiving surface corresponding to the irradiation area of ​​the illumination light in the fundus Ef and has a predetermined aperture width, is opened for an aperture time Td1.

[0200] For example, when the deflection angle range is DR2 as described above, the control unit 100 controls the optical scanner 30 to deflect the illumination light within the range corresponding to the deflection angle range DR2 for an irradiation time Td2 corresponding to the deflection angle range DR2, thereby illuminating the fundus Ef. Furthermore, the control unit 100 controls the image sensor 51 so that an aperture range OR62, which overlaps with the irradiation range ILR62 on the light-receiving surface corresponding to the irradiation area of ​​the illumination light in the fundus Ef and has a predetermined aperture width, is opened for an aperture time Td2.

[0201] Similarly, for example, when the deflection angle range is DR3 as described above, the control unit 100 controls the optical scanner 30 to deflect the illumination light within the range corresponding to the deflection angle range DR3 for an irradiation time Td3 corresponding to the deflection angle range DR3, thereby illuminating the fundus Ef. Furthermore, the control unit 100 controls the image sensor 51 so that an aperture range OR63, which overlaps with the irradiation range ILR63 on the light-receiving surface corresponding to the irradiation area of ​​the illumination light in the fundus Ef and has a predetermined aperture width, is opened for an aperture time Td3. For example, in the imaging area R IMG The closer to the center, the shorter the irradiation time (aperture time).

[0202] The control unit 100 reads out the light reception results obtained from the light-receiving elements in the aperture range OR61, OR62, OR63, ... using a rolling shutter method, and uses the light reception results obtained from the light-receiving elements in the range that overlaps with the illumination range ILR61, ILR62, ILR63, ... from the read-out light reception results to cause the data processing unit 200 to form an image of the fundus Ef.

[0203] The control of the optical scanner 30 and image sensor 51 is repeated in the same manner, and the imaging area R in the fundus Ef is illuminated by the illumination light. IMG Once the irradiation (scanning) is complete, the control unit 100 synthesizes the images formed for each frame to create the imaging area R IMG The data processing unit 200 is instructed to create an image of the entire fundus Ef, which is depicted in detail.

[0204] For example, the memory unit 102 stores fifth control information in which the illumination time (aperture time of the aperture range) is pre-associated with the deflection angle range (position of the target to be photographed). The control unit 100 can refer to the fifth control information and control the optical scanner 30 to illuminate the illumination area with illumination light for the illumination time corresponding to the position of the target to be photographed, and control the image sensor 51 to set an aperture range having a predetermined aperture width for the aperture time corresponding to the position of the target to be photographed.

[0205] As described above, the control unit 100 controls the optical scanner 30 so that the illumination light illuminates the illumination area in the fundus Ef for an illumination time corresponding to the position of the illumination area in the fundus Ef for each frame period, sets an aperture range that opens for an aperture time corresponding to the position of the illumination area, and controls the image sensor 51 to read out the light reception result of the aperture range using a rolling shutter method. In some embodiments, aperture ranges with different aperture widths are set according to the position of the illumination area in the fundus Ef.

[0206] According to the second operation example of the fourth embodiment, the aperture range on the light-receiving surface of the image sensor 51, which can read out the light-receiving result using a rolling shutter method, can be moved while changing the illumination time (aperture time) according to the illumination area of ​​the illumination light in the fundus Ef. This makes it possible to adjust the amount of illumination light according to the position of the target of imaging. As a result, the entire imaging area can be illuminated with a uniform amount of light without reducing the amount of illumination light at positions far from the center of the imaging area (for example, positions with a large deflection angle). Therefore, it becomes possible to acquire higher quality images of the fundus Ef.

[0207] [Effect] The ophthalmic apparatus, its control method, and the operation of the program according to this embodiment will be described.

[0208] An ophthalmic apparatus (1) according to several embodiments includes an illumination optical system (20), an optical scanner (30), an imaging optical system (40), and a control unit (100, main control unit 101). The illumination optical system generates slit-shaped illumination light. The optical scanner deflects the illumination light and guides it to a predetermined area (fundus Ef) of the eye under examination (E). The imaging optical system guides the reflected light from the predetermined area to an image sensor (51) whose aperture range on the light-receiving surface can be set. The control unit controls the optical scanner and the image sensor so that the illumination range on the light-receiving surface corresponding to the illumination range of the predetermined area overlaps with the aperture range, and the light reception result of the reflected light in the aperture range that overlaps with the illumination range is acquired.

[0209] In this configuration, it becomes possible to arbitrarily change the illumination area of ​​the illuminating light at a predetermined part of the eye under examination and the aperture range of the light-receiving surface of the image sensor in a synchronized manner. This makes it possible to acquire a clear image of the predetermined area with a simple configuration while suppressing the effects of unwanted scattered light.

[0210] In some embodiments of ophthalmic devices, the control unit moves the aperture range and controls the optical scanner and image sensor so that the irradiation range overlaps with the aperture range after the movement.

[0211] According to this embodiment, the illumination area of ​​the illumination light at a predetermined part of the eye under examination can be changed in accordance with the position of the aperture range on the light-receiving surface of the image sensor.

[0212] In some embodiments of ophthalmic devices, the control unit moves the irradiation range and controls the optical scanner and image sensor so that the aperture range overlaps with the irradiation range after the movement.

[0213] According to this embodiment, the illumination area of ​​the illumination light at a predetermined part of the eye under examination can be changed in accordance with the position of the aperture range on the light-receiving surface of the image sensor.

[0214] In some embodiments of ophthalmic devices, the control unit controls the optical scanner to scan the illumination area with illumination light.

[0215] According to this embodiment, illumination light can be irradiated onto an illumination area of ​​a desired shape and size.

[0216] In some embodiments of the ophthalmic apparatus, the control unit controls the optical scanner and the image sensor so that the target area for aperture in a predetermined part corresponding to the aperture range covers the imaging area during the one-frame period in which the image sensor captures the light reception result of the aperture range.

[0217] This configuration makes it possible to acquire clear images of a predetermined area with a simple configuration, while reducing the burden on the eye being examined and suppressing the effects of unwanted scattered light.

[0218] In some embodiments of the ophthalmic apparatus, the control unit controls the optical scanner to deflect the illumination light at a deflection speed corresponding to the position of the illumination area of ​​the illumination light at a predetermined site, and controls the image sensor to set an aperture range having an aperture width corresponding to the position of the illumination area.

[0219] According to this configuration, the entire shooting area can be illuminated with a uniform amount of light without reducing the amount of illumination light at positions far from the center of the shooting area (for example, positions with a large deflection angle). Therefore, it becomes possible to acquire higher-quality images of a predetermined area.

[0220] In some embodiments of the ophthalmic apparatus, the control unit changes the target area for aperture in a predetermined part corresponding to the irradiation area or aperture range for each frame period in which the light reception result of the aperture range is captured by the image sensor, and controls the optical scanner and image sensor so that the target area for aperture covers the imaging area over two or more frame periods.

[0221] According to this embodiment, it becomes possible to acquire a clear image of a predetermined area with a simple configuration while suppressing the effects of unwanted scattered light as well as fixation tremors of the eye being examined.

[0222] In some embodiments of the ophthalmic apparatus, the control unit controls the optical scanner to deflect the illumination light at a deflection speed corresponding to the position of the illumination area of ​​a predetermined part for each frame period, and controls the image sensor to set an aperture range having an aperture width corresponding to the position of the illumination area.

[0223] According to this configuration, the entire shooting area can be illuminated with a uniform amount of light without reducing the amount of illumination light at positions far from the center of the shooting area (for example, positions with a large deflection angle). Therefore, it becomes possible to acquire higher-quality images of a predetermined area.

[0224] In some embodiments of the ophthalmic apparatus, the control unit controls the optical scanner and image sensor so that, for each frame period in which the image sensor captures the light reception result of the aperture range, the illuminated area coincides with the aperture target area in a predetermined part corresponding to the aperture range, and the aperture target area covers the imaging area over two or more frame periods.

[0225] According to this embodiment, it becomes possible to acquire a clear image of a predetermined area with a simple configuration and processing while suppressing the effects of unwanted scattered light as well as fixation tremors of the eye being examined.

[0226] In some embodiments of the ophthalmic apparatus, the control unit controls the optical scanner so that the illumination light illuminates the illumination area for an illumination time corresponding to the position of the illumination light area in a predetermined area for each frame period, and controls the image sensor to set an aperture range that opens for an aperture time corresponding to the position of the illumination area.

[0227] According to this configuration, the entire shooting area can be illuminated with a uniform amount of light without reducing the amount of illumination light at positions far from the center of the shooting area (for example, positions with a large deflection angle). Therefore, it becomes possible to acquire higher-quality images of a predetermined area.

[0228] In some embodiments of ophthalmic devices, the control unit acquires the light reception results obtained by the image sensor using a global shutter method.

[0229] In this configuration, a simple setup using an image sensor capable of reading out light reception results with a global shutter method makes it possible to acquire a clear image of a predetermined area while suppressing the effects of unwanted scattered light.

[0230] In some embodiments of the ophthalmic apparatus, the control unit acquires the light reception results obtained by the image sensor using a rolling shutter method, and controls the optical scanner and image sensor so that the illuminated area overlaps with the aperture target area in a predetermined part corresponding to the aperture range for each frame period in which the light reception results of the aperture range are captured by the image sensor, and the aperture target area covers the shooting area for two or more frame periods.

[0231] According to this embodiment, a simple configuration and simple processing using an image sensor capable of acquiring light reception results with a rolling shutter method makes it possible to acquire a clear image of a predetermined area while suppressing the effects of unwanted scattered light as well as fixation tremors of the eye being examined.

[0232] In some embodiments of the ophthalmic apparatus, the control unit controls the optical scanner so that, for each frame period, the illumination light illuminates the illumination area for an illumination time corresponding to the position of the illumination light illumination area at a predetermined site, and controls the image sensor so that it reads out the light reception result of the aperture range corresponding to the position of the illumination area using a rolling shutter method.

[0233] In this configuration, a simple setup using an image sensor capable of reading light reception results with a rolling shutter allows for uniform illumination of the entire shooting area without reducing the amount of illumination light at positions far from the center of the shooting area (for example, positions with a large deflection angle). Therefore, it becomes possible to acquire higher-quality images of a predetermined area.

[0234] Some ophthalmic devices according to certain embodiments include an image forming unit (data processing unit 200) that forms an image of a predetermined area based on the light reception results captured in an aperture range that overlaps with the irradiation range.

[0235] This configuration makes it possible to acquire a clear image of a predetermined area with a simple setup while suppressing the effects of unwanted scattered light.

[0236] In some embodiments of the ophthalmic apparatus, the illumination optical system includes a slit (22) whose aperture can be positioned at a location that is optically substantially conjugate to a predetermined site, and illumination light is generated by light from a light source (10) passing through the aperture; the optical scanner can be positioned at a location that is optically substantially conjugate to the iris of the eye under examination; and the light-receiving surface can be positioned at a location that is optically substantially conjugate to a predetermined site.

[0237] According to this configuration, by irradiating a predetermined area of ​​the eye under examination with slit-shaped illumination light, it becomes possible to acquire a clear image of the predetermined area with a simple configuration while suppressing the effects of unwanted scattered light.

[0238] In some embodiments of the ophthalmic apparatus, the illumination optical system includes an iris diaphragm (21) positioned between the light source and the slit, with an opening formed at an eccentric position with respect to the optical axis of the illumination optical system and positioned to be substantially conjugate to the iris, and a hole mirror (45) with an opening formed to be positioned to be substantially conjugate to the iris and which connects the optical path of the illumination light deflected by the optical scanner with the optical path of the imaging optical system.

[0239] According to this configuration, the pupil can be segmented and illumination light can be shone onto a predetermined part of the eye under examination, making it possible to obtain a higher-resolution image of the eye under examination.

[0240] In some embodiments of ophthalmic devices, the designated site is the fundus (Ef).

[0241] This configuration makes it possible to acquire clear images of the fundus of the eye with a simple setup while suppressing the effects of unwanted scattered light.

[0242] Some embodiments include a control method for an ophthalmic device (1) comprising: an illumination optical system (20) that generates slit-shaped illumination light; an optical scanner (30) that deflects the illumination light and guides it to a predetermined part (fundus Ef) of the eye under examination (E); and an imaging optical system (40) that guides the reflected light of the illumination light from the predetermined part to an image sensor (51) capable of setting the aperture range on the light-receiving surface. The control method for the ophthalmic device includes a control step of controlling the optical scanner and the image sensor so that the illumination range on the light-receiving surface corresponding to the illumination range of the predetermined part overlaps with the aperture range, and the light reception result of the reflected light in the aperture range that overlaps with the illumination range is acquired.

[0243] In this configuration, it becomes possible to arbitrarily change the illumination area of ​​the illumination light at a predetermined part of the eye under examination and the aperture range of the light-receiving surface of the image sensor in a synchronized manner. This makes it possible to acquire a clear image of the predetermined area while suppressing the effects of unwanted scattered light with a simple configuration and control.

[0244] In some embodiments of ophthalmic apparatus control methods, the control steps include an image sensor control step of controlling an image sensor to move the aperture range, and an optical scanner control step of controlling an optical scanner so that the illumination range overlaps with the moved aperture range.

[0245] According to this embodiment, the illumination area of ​​the illumination light at a predetermined part of the eye under examination can be changed in accordance with the position of the aperture range on the light-receiving surface of the image sensor.

[0246] In some embodiments of ophthalmic apparatus control methods, the control steps include an optical scanner control step of moving the irradiation range and an image sensor control step of controlling the image sensor so that the aperture range overlaps with the irradiation range after movement.

[0247] According to this embodiment, the illumination area of ​​the illumination light at a predetermined part of the eye under examination can be changed in accordance with the position of the aperture range on the light-receiving surface of the image sensor.

[0248] In some embodiments of ophthalmic apparatus control methods, the control step involves controlling an optical scanner to scan an illumination area with illumination light.

[0249] According to this embodiment, illumination light can be irradiated onto an illumination area of ​​a desired shape and size.

[0250] In some embodiments of ophthalmic apparatus control methods, the control step involves controlling the optical scanner and image sensor during a one-frame period in which the image sensor captures the light reception results of the aperture range, so that the aperture target area at a predetermined location corresponding to the aperture range covers the imaging area.

[0251] This configuration makes it possible to acquire a clear image of a predetermined area with a simple configuration and control, while reducing the burden on the eye being examined and suppressing the effects of unwanted scattered light.

[0252] In some embodiments of ophthalmic apparatus control methods, the control step involves changing the target aperture area in a predetermined part corresponding to the irradiation area or aperture range for each frame period in which the image sensor captures the light reception result of the aperture range, and controlling the optical scanner and image sensor so that the target aperture area covers the imaging area over two or more frame periods.

[0253] According to this configuration, the entire shooting area can be illuminated with a uniform amount of light without reducing the amount of illumination light at positions far from the center of the shooting area (for example, positions with a large deflection angle). Therefore, it becomes possible to acquire higher-quality images of a predetermined area.

[0254] In some embodiments of ophthalmic apparatus control methods, the control step involves controlling the optical scanner and image sensor so that, for each frame period in which the image sensor captures the light reception result of the aperture range, the illuminated area coincides with the aperture target area in a predetermined part corresponding to the aperture range, and the aperture target area covers the imaging area over two or more frame periods.

[0255] According to such an aspect, it is possible to obtain a clear image of a predetermined site with a simple configuration and control while suppressing the influence of unnecessary scattered light and the influence of fixation micro-vibration of the eye to be examined, etc.

[0256] In the control method of the ophthalmic apparatus according to some embodiments, the image sensor can acquire the light reception result by a global shutter method.

[0257] According to such an aspect, with a simple configuration and control using an image sensor capable of reading out the light reception result by a global shutter method, it is possible to obtain a clear image of a predetermined site while suppressing the influence of unnecessary scattered light.

[0258] In the control method of the ophthalmic apparatus according to some embodiments, the image sensor can acquire the light reception result by a rolling shutter method, and the control step includes an aperture target region at a predetermined site corresponding to the aperture range for each frame period in which the light reception result of the aperture range is captured by the image sensor, and controls the light scanner and the image sensor so that the aperture target region covers the imaging region over two or more frame periods.

[0259] According to such an aspect, with a simple configuration and simple processing using an image sensor capable of acquiring the light reception result by a rolling shutter method, it is possible to obtain a clear image of a predetermined site while suppressing the influence of unnecessary scattered light and the influence of fixation micro-vibration of the eye to be examined, etc. <000,0901> The control method of the ophthalmic apparatus according to some embodiments includes an image forming step of forming an image of a predetermined site based on the light reception result captured in the aperture range.

[0261] According to such an aspect, it is possible to obtain a clear image of a predetermined site with a simple configuration and control while suppressing the influence of unnecessary scattered light.

[0262] In the control method of the ophthalmic apparatus according to some embodiments, the predetermined site is the fundus of the eye.

[0263] According to this configuration, it becomes possible to acquire clear images of the fundus of the eye with a simple configuration and control, while suppressing the effects of unwanted scattered light.

[0264] Some embodiments of the program cause a computer to perform each step of the control method for the ophthalmic device described in any of the above.

[0265] Such a program makes it possible to acquire clear images of a specific area while suppressing the effects of unwanted scattered light, using a simple configuration and control.

[0266] The embodiments described above are merely examples of how to carry out this invention. Anyone intending to carry out this invention may make any modifications, omissions, additions, etc., within the scope of the gist of this invention.

[0267] It is possible to arbitrarily combine the contents of two or more embodiments from the above-described embodiments.

[0268] In the above embodiment, the ophthalmic device may have any functions usable in the field of ophthalmology, such as an axial length measurement function, an intraocular pressure measurement function, an optical coherence tomography (OCT) function, and an ultrasound examination function. The axial length measurement function is implemented by an optical coherence tomograph or the like. Alternatively, the axial length measurement function may be implemented by projecting light onto the eye under examination and detecting the reflected light from the fundus while adjusting the Z-direction (anterior-posterior direction) position of the optical system relative to the eye under examination. The intraocular pressure measurement function is implemented by a tonometer or the like. The OCT function is implemented by an optical coherence tomograph or the like. The ultrasound examination function is implemented by an ultrasound diagnostic device or the like. Furthermore, it is also possible to apply this invention to a device (combination device) that has two or more of these functions.

[0269] In some embodiments, a program is provided for causing a computer to execute the control method of the ophthalmic device described above. Such a program can be stored on any non-transitory recording medium that is readable by the computer. The recording medium may be an electronic medium utilizing magnetism, light, magneto-optical technology, semiconductors, etc. Typically, the recording medium is a magnetic tape, magnetic disk, optical disk, magneto-optical disk, flash memory, solid-state drive, etc. It is also possible to send and receive this program over a network such as the Internet or a LAN. [Explanation of Symbols]

[0270] 1 Ophthalmology equipment 10 light source 20 Illumination optical system 21 Iris Diaphragm 22 slits 23, 41, 44, 48 Relay Lens 30 Optical Scanners 35 Projection optical system 40. Imaging optical system 42 Black Dot Plates 43 Reflective mirror 45 hole mirror 46 Objective lens 47 Focusing Lens 49. Imaging lens 50 Imaging device 51 Image Sensor 100 Control Unit 101 Main Control Unit 102 Storage section 200 Data Processing Unit E. Eye being examined Ef fundus

Claims

1. An illumination optical system includes a light source and a slit whose aperture can be positioned at a location that is substantially conjugate to a predetermined part of the eye under examination, wherein light from the light source passes through the aperture to generate slit-shaped illumination light, An optical scanner that can be positioned in a position approximately conjugate to the iris of the eye under examination, is configured to change the scanning speed, and deflects the illumination light to guide it to the predetermined area, A photographic optical system that guides the reflected light of the illumination light from the predetermined part to an image sensor capable of setting the aperture range of a light-receiving surface that can be positioned at a position substantially conjugate to the predetermined part, A control unit controls the optical scanner and the image sensor such that, depending on the condition of the eye under examination, the slit is moved in the optical axis direction of the illumination optical system, and the relative position and orientation of the light source with respect to the slit is changed, and further, the width of the aperture range on the light-receiving surface is changed according to the deflection angle of the illumination light by the optical scanner, and the illumination range on the light-receiving surface corresponding to the illumination range of the predetermined part overlaps with the aperture range, and the light reception result of the reflected light in the aperture range that overlaps with the illumination range is obtained. An image forming unit that forms an image of the predetermined area based on the light reception results captured in the aperture range that overlaps with the irradiation range, Includes, The control unit changes the width of the aperture range according to the deflection angle for each frame period, and synthesizes the images formed using the light reception results in each frame to obtain an image of the predetermined area. An ophthalmic device that performs image formation in each frame and reception of the reflected light in other frames in parallel.

2. The aforementioned designated area is the fundus of the eye. The ophthalmic device according to feature 1.

3. An illumination optical system includes a light source and a slit whose aperture can be positioned at a location that is substantially conjugate to a predetermined part of the eye under examination, wherein light from the light source passes through the aperture to generate slit-shaped illumination light, An optical scanner that can be positioned in a position approximately conjugate to the iris of the eye under examination, is configured to change the scanning speed, and deflects the illumination light to guide it to the predetermined area, A control method for an ophthalmic apparatus, comprising: an imaging optical system that guides the reflected light of the illumination light from the predetermined part to an image sensor capable of setting an aperture range on a light-receiving surface that can be positioned at a position substantially conjugate to the predetermined part; Depending on the condition of the eye being examined, the slit is moved in the optical axis direction of the illumination optical system, and the relative position and orientation of the light source with respect to the slit are changed, and further, the width of the aperture range on the light-receiving surface is changed according to the deflection angle of the illumination light by the optical scanner. A control step to control the optical scanner and the image sensor so that the illumination range on the light-receiving surface corresponding to the illumination range of the illumination light in the imaging area of ​​the predetermined part overlaps with the aperture range, and to acquire the light-receiving result of the reflected light in the aperture range that overlaps with the illumination range. An image forming step of forming an image of the predetermined area based on the light reception results captured in the aperture range, Includes, The control step involves changing the width of the aperture range according to the deflection angle for each frame period, and acquiring an image of the predetermined area by synthesizing the images formed using the light reception results in each frame. A control method for an ophthalmic device, which performs the formation of an image in each frame and the reception of the reflected light in other frames in parallel.

4. The aforementioned designated area is the fundus of the eye. A method for controlling an ophthalmic device according to feature 3.

5. A program characterized by causing a computer to execute each step of the control method for an ophthalmic device described in claim 3 or claim 4.

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