Ophthalmic device

Abstract

An ophthalmic apparatus includes two or more light sources, an illumination optical system, a light receiving optical system, and an optical path dividing member. The illumination optical system includes an iris diaphragm and an illumination diaphragm, and illuminates the subject eye with light from the two or more light sources by means of the iris diaphragm and the illumination diaphragm. The iris diaphragm is disposed at an iris conjugate position which is substantially optically conjugate with the iris of the subject eye, and has two or more openings formed therein. The illumination aperture is disposed at a fundus conjugate position that is substantially optically conjugate with the fundus of the subject eye. The light receiving optical system guides return light from the subject eye to the imaging element. The optical path dividing member spatially divides the optical path of the illumination optical system and the optical path of the light receiving optical system in a plane at the iris conjugate position such that the images of the two or more openings are disposed around the light receiving opening through which the return light passes. A center of a corresponding one of the two or more openings is disposed on an optical axis of each of the two or more light sources.

Description

Technical Field

[0001] The present invention relates to an ophthalmic device. Background Art

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

[0003] For example, Patent Documents 1 and 2 disclose an ophthalmic device that illuminates the eye under examination with slit-shaped light and detects the return light using a CMOS (Complementary Metal Oxide Semiconductor) image sensor. This ophthalmic device can capture an image of the eye under examination with a simple configuration by adjusting the illumination pattern and the timing of the movement of the light-receiving area in the CMOS image sensor.

[0004] Patent Document 1: U.S. Patent No. 7,831,106

[0005] Patent Document 2: U.S. Patent No. 8,237,835 Summary of the Invention

[0006] Such an ophthalmologic apparatus is preferably configured such that an illumination opening through which slit-shaped light as illumination light passes and a light receiving opening (imaging opening) through which return light from the inspected eye as imaging light passes are separated in the iris (pupil) of the inspected eye.

[0007] Moreover, in order to suppress the optical aberration of the eyeball optical system, it is preferred that the light receiving opening is arranged on the optical axis of the eyeball optical system, and two or more illumination openings are arranged around the light receiving opening. At this time, the light from the light source is irradiated to the iris aperture arranged at a position roughly optically conjugate with the iris of the eye to be examined, thereby forming illumination light. In order to use such illumination light to uniformly illuminate the fundus and other observation areas, it is sought that the change in the light amount distribution (light distribution) of the illumination light emitted from the iris aperture at each angle is small. In addition, it is also necessary to use a slit to generate slit-shaped light, and the amount of light reaching the observation area is significantly reduced. Therefore, in order to improve the lighting efficiency, it is preferred to completely illuminate the iris aperture formed with two or more openings with the light from the light source.

[0008] When using a single light source to achieve the above-mentioned illumination, the efficiency of the illumination light relative to the light output of the light source is significantly poor. Furthermore, there is the problem of limiting the light output of the light source due to heat generation. As a result, there is the problem of not being able to obtain sufficient illumination light. Furthermore, suppressing heat generation to increase the light output requires a cooling mechanism such as air cooling, which complicates the dust control structure within the device.

[0009] The present invention has been made in view of the above circumstances, and one of its objects is to provide a new technology for brightly illuminating an observation area with a simple structure.

[0010] One embodiment is an ophthalmic device comprising two or more light sources, an illumination optical system, a light receiving optical system, and an optical path dividing component. The illumination optical system comprises an iris diaphragm and an illumination aperture, and the iris diaphragm and the illumination aperture are used to illuminate the eye to be examined with light from the two or more light sources. The iris diaphragm is arranged at an iris conjugate position that is roughly optically conjugate with the iris of the eye to be examined, and has two or more openings. The illumination aperture is arranged at a fundus conjugate position that is roughly optically conjugate with the fundus of the eye to be examined. The light receiving optical system guides the return light from the eye to be examined to the imaging element. The optical path dividing component spatially divides the optical path of the illumination optical system and the optical path of the light receiving optical system in a plane at the iris conjugate position so that the images of the two or more openings are arranged around the light receiving opening through which the return light passes. The centers of the corresponding openings of the two or more openings are arranged on the optical axes of the two or more light sources.

[0011] According to the present invention, it is possible to provide a new technology for brightly illuminating an observation area with a simple structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic diagram showing a configuration example of the optical system of the ophthalmologic apparatus according to the first embodiment.

[0013] Figure 2 This is a schematic diagram showing a configuration example of the optical system of the ophthalmologic apparatus according to the first embodiment.

[0014] Figure 3 This is a schematic diagram showing a configuration example of the optical system of the ophthalmologic apparatus according to the first embodiment.

[0015] Figure 4 This is a schematic diagram for explaining the optical system of the ophthalmologic apparatus according to the first embodiment.

[0016] Figure 5 This is a schematic diagram for explaining the optical system of the ophthalmologic apparatus according to the first embodiment.

[0017] Figure 6 This is a schematic diagram for explaining the optical system of the ophthalmologic apparatus according to the first embodiment.

[0018] Figure 7 This is a schematic diagram for explaining the operation of the ophthalmologic apparatus according to the first embodiment.

[0019] Figure 8 This is a schematic diagram for explaining the operation of the ophthalmologic apparatus according to the first embodiment.

[0020] Figure 9 This is a schematic diagram for explaining the operation of the ophthalmologic apparatus according to the first embodiment.

[0021] Figure 10 This is a schematic diagram showing a configuration example of a control system of the ophthalmologic apparatus according to the first embodiment.

[0022] Figure 11 This is a flowchart of an operation example of the ophthalmologic apparatus according to the first embodiment.

[0023] Figure 12 This is a schematic diagram showing a configuration example of an optical system of an ophthalmologic apparatus according to a second embodiment.

[0024] Figure 13 It is a schematic diagram showing a configuration example of an optical system of an ophthalmologic apparatus according to a second embodiment.

[0025] Figure 14 This is a schematic diagram showing a configuration example of an optical system of an ophthalmologic apparatus according to a third embodiment.

[0026] Figure 15 This is a schematic diagram showing a configuration example of an optical system of an ophthalmologic apparatus according to a third embodiment. DETAILED DESCRIPTION

[0027] An example of an embodiment of the ophthalmologic apparatus according to the present invention will be described in detail with reference to the accompanying drawings. The contents of the documents described in this specification may be appropriately cited as the contents of the following embodiments.

[0028] The ophthalmic device according to the embodiments can acquire an image of the eye under examination using a slit scanning method using slit-shaped illumination light. Specifically, the ophthalmic device uses an optical scanner to illuminate a predetermined portion of the eye under examination while moving the slit-shaped illumination position (irradiation range) of the illumination light. Return light from the eye under examination is received using an image sensor having light-receiving elements arranged one-dimensionally or two-dimensionally. Synchronously with the movement of the illumination light illumination position, the light-receiving result of the return light is read from the light-receiving element at the light-receiving position of the return light corresponding to the illumination light illumination position.

[0029] In an ophthalmic device, a slit-shaped illumination aperture, through which slit-shaped illumination light passes, and a light-receiving aperture (imaging aperture), through which return light from the eye to be examined, serving as imaging light, pass, are separated at the iris (pupil) of the examined eye (or at a position substantially optically conjugate with the iris (pupil) (iris (pupil) conjugate position)). To suppress optical aberrations in the light-receiving system, the light-receiving aperture is positioned on the optical axis, and two or more illumination apertures are arranged around the light-receiving aperture.

[0030] An ophthalmic device includes two or more light sources, an illumination optical system, a light receiving optical system, and an optical path dividing component. The illumination optical system includes an iris diaphragm positioned approximately optically conjugate with the iris of the eye being examined, and a slit serving as the illumination diaphragm positioned approximately optically conjugate with an observation site (e.g., the fundus) of the eye being examined. The iris diaphragm has two or more openings. The two or more light sources are disposed corresponding to the two or more openings formed in the iris diaphragm. The centers of the corresponding openings in the iris diaphragm are positioned on the optical axes of the two or more light sources.

[0031] In some embodiments, the two or more light sources are respectively arranged adjacent to corresponding openings of the two or more openings formed in the iris aperture, with the optical axes of the light sources passing through the center of the light-emitting areas of the light sources. In some embodiments, the two or more light sources are respectively arranged at positions that are substantially optically conjugate with the corresponding openings of the two or more openings formed in the iris aperture. In some embodiments, light emitted by each of the two or more light sources is guided through a light guide component to the corresponding opening of the two or more openings formed in the iris aperture.

[0032] The illumination optical system illuminates the iris diaphragm with light from two or more light sources, and then illuminates the slit with illumination light that has passed through two or more openings formed in the iris diaphragm corresponding to the two or more light sources, thereby forming slit-shaped illumination light. The light receiving optical system receives, via an image sensor, return light from the observation area illuminated by the illumination light, which has passed through the light receiving openings.

[0033] The images formed at the two or more openings of the iris diaphragm are formed on a plane at an iris conjugate position that is substantially optically conjugate with the iris of the eye to be examined. The optical path dividing component spatially divides the optical path of the illumination optical system and the optical path of the light-receiving optical system on a plane at the iris conjugate position (a plane intersecting the optical axis) so that the images formed at the two or more openings of the iris diaphragm are arranged around the light-receiving opening.

[0034] This improves the efficiency of light emission from the light source, thereby suppressing any increase in the amount of light emitted by the light source. Consequently, the heat generated by each of the two or more light sources can be suppressed, allowing for bright illumination of the observation area with a simple structure. In particular, by using a high-brightness light source, which exhibits higher brightness as the luminous area decreases, the efficiency of light emission from the light source can be further improved.

[0035] For example, it is possible to use a lens or other device to magnify and project the iris diaphragm by converting the magnification of light from a single light source. In this case, due to the optical relationship between lateral magnification and angular magnification, the directionality of the illumination light passing through the opening formed in the iris diaphragm increases, making it difficult to fully illuminate the longitudinal direction of the opening formed in the slit. In contrast, the above-described configuration allows for uniform illumination of the entire iris diaphragm. As a result, the size of the illumination opening (the image of the opening formed in the iris diaphragm) can be increased, improving the numerical aperture (NA) of the observation area and enabling clearer observation of the observation area.

[0036] In some embodiments, the observation site is the anterior or posterior eye. The anterior eye includes the cornea, iris, lens, ciliary body, suspensory ligament, etc. The posterior eye includes the vitreous body, fundus or its vicinity (retina, choroid, sclera, etc.).

[0037] The control method of an ophthalmic device according to the embodiment includes one or more steps for implementing a process executed by a processor (computer) in the ophthalmic device according to the embodiment. The program according to the embodiment causes the processor to execute each step of the control method of the ophthalmic device according to the embodiment. The storage medium according to the embodiment is a non-transitory storage medium (storage medium) that stores the program according to the embodiment.

[0038] In this specification, the term "processor" refers to circuits such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), a programmable logic device (e.g., a SPLD (Simple Programmable Logic Device), a CPLD (Complex Programmable Logic Device), and an FPGA (Field Programmable Gate Array). The processor implements the functions described in the embodiments by, for example, reading and executing a program stored in a storage circuit or storage device.

[0039] In the following embodiments, two openings are formed in the iris diaphragm, and the fundus is observed. Furthermore, a position optically conjugate with the iris (pupil) of the examined eye, or its vicinity, is referred to as an "iris (pupil) conjugate position," and a position optically conjugate with the fundus of the examined eye, or its vicinity, is referred to as a "fundus conjugate position." In the following embodiments, unless otherwise specified, the iris conjugate position may be substituted for the pupil conjugate position.

[0040] Hereinafter, the X direction is a direction perpendicular to the optical axis of the objective lens (horizontal direction), the Y direction is a direction perpendicular to the optical axis of the objective lens (vertical direction), and the Z direction is the optical axis of the objective lens.

[0041] <First embodiment>

[0042] [Optical system structure]

[0043] exist Figures 1 to 3 Detailed description is given of a configuration example of the optical system of the ophthalmologic apparatus according to the first embodiment. Figure 1 A configuration example of the optical system of the ophthalmologic apparatus 1 according to the first embodiment is shown. Figure 2 It is schematically shown Figure 1 FIG. 2 is a diagram showing a structural example of the iris diaphragm 21 . Figure 3 It is a schematic diagram showing the YZ plane Figure 1 FIG. 2 is a diagram showing the structure of the optical system of the illumination optical system 20. Figures 1 to 3 In the drawings, the same parts are marked with the same reference numerals and the description is omitted as appropriate.

[0044] like Figure 1 As shown, the ophthalmic apparatus 1 includes an illumination system 20, a light scanner 30, a projection system 35, a photographic optical system 40, and an imaging device 50. The illumination system 20 includes light sources 10A and 10B. In some embodiments, the light sources 10A and 10B are disposed outside the illumination system 20. In some embodiments, the illumination system 20 includes at least one of the light scanner 30 and the projection system 35. In some embodiments, the photographic optical system 40 includes the imaging device 50. In some embodiments, the projection system 35 or the illumination system 20 includes the light scanner 30.

[0045] (Illumination Optical System 20)

[0046] The illumination optical system 20 generates slit-shaped illumination light using the light from the light sources 10A and 10B, and guides the generated illumination light to the optical scanner 30 .

[0047] The illumination optical system 20 includes light sources 10A and 10B, an iris diaphragm 21, a condenser lens 23, a slit 22 serving as an illumination diaphragm, and a relay lens system RL1. The iris diaphragm 21 has two openings formed at positions offset from the optical axis O of the illumination optical system 20. The light source 10A is provided corresponding to one of the two openings, and the light source 10B is provided corresponding to the other of the two openings.

[0048] (Light sources 10A, 10B)

[0049] The light sources 10A and 10B include visible light sources that generate light in the visible region. For example, the light sources 10A and 10B generate light having a central wavelength in the wavelength range of 420 nm to 700 nm. Such light sources 10A and 10B include, for example, LEDs (Light Emitting Diodes), for example, Figure 3 The light source 10A may have the same structure as the light source 10B.

[0050] (iris aperture 21)

[0051] The iris diaphragm 21 (specifically, an opening described later) is configured to be arranged at an iris conjugate position Q of the eye E by alignment between the eye E and the optical system. Two openings are formed at positions separated from the optical axis O in the iris diaphragm 21 .

[0052] like Figure 2 As shown, the iris diaphragm 21 is formed with a first opening 21A and a second opening 21B. Specifically, the position corresponding to the optical axis O of the illumination optical system 20 is arranged at the center connecting the first opening 21A and the second opening 21B (corresponding to the center of the iris diaphragm 21 described later). Figure 5 The first opening 21A and the second opening 21B are formed on a straight line with respect to the center Lca and Lcb shown in the figure. For example, the first opening 21A and the second opening 21B are formed to be line-symmetrical with respect to a straight line passing through the optical axis O and extending in a direction corresponding to the longitudinal direction of the slit 22. The first opening 21A and the second opening 21B each have an arcuate (crescent) shape. The arcuate is an area surrounded by the minor arc of a circle or ellipse and the chord of the minor arc. For example, the direction of the chord of the arcuate shape is approximately parallel to the direction corresponding to the longitudinal direction of the opening formed in the slit 22.

[0053] The opening formed in the iris diaphragm 21 defines the incident position (incident shape) of the illumination light on the iris of the eye to be examined E. For example, Figure 2 As shown, by forming the first opening 21A and the second opening 21B, when the pupil center of the inspected eye E is arranged on the optical axis O, the illumination light can be incident into the eye from a position eccentric from the pupil center (specifically, a position point-symmetrical about the pupil center).

[0054] In the first embodiment, the light source 10A is disposed adjacent to the first opening 21A, and the light source 10B is disposed adjacent to the second opening 21B.

[0055] exist Figure 4 Schematically shows the light emitting area of ​​the light source 10A. Figure 4 This figure schematically shows the light emitting area of ​​the surface-mounted LED as the light source 10A from the emission direction. Figure 4 Although the light emitting area of ​​the light source 10A is shown in FIG, the light emitting area of ​​the light source 10B is also the same.

[0056] The light source 10A includes a light emitting element (LED element) and a substrate (not shown) on which the light emitting element is mounted. The light emitting element and the substrate are electrically connected via a bonding wire for supplying an electrical signal to the light emitting element.

[0057] The light source 10A emits light from a substantially quadrilateral light emitting area Ld on the light emitting element. At this time, the closer the periphery of the light emitting area Ld is to the center Lc, the stronger the light emission intensity. Figure 4 In the figure, the luminous intensity range within the luminous region LD is divided into multiple ranges, and the luminous region LD is divided by dotted lines to schematically illustrate the luminous intensity of each region. Furthermore, a bonding region for electrically connecting the aforementioned bonding wires is provided around the periphery of the luminous region Ld. Although this compromises the symmetry of the luminous intensity distribution within the luminous region Ld, the luminous region Ld is essentially a roughly rectangular shape.

[0058] The centers of the first and second openings 21A, 21B formed in the iris diaphragm 21 are located on the optical axes of the respective light sources 10A, 10B. The centers of the openings can be the centers of both the long and short sides of the openings, or the centroid of the openings. The long side of the opening refers to the long side of a rectangle circumscribing the opening, while the short side of the opening refers to the short side of the rectangle circumscribing the opening.

[0059] Specifically, the light source 10A is positioned adjacent to the iris diaphragm 21, with the center of the first opening 21A aligned on its optical axis. The optical axis of the light source 10A is defined as the optical axis passing through the center Lc of the light-emitting area Ld of the light source 10A. The center Lc of the light-emitting area Ld can be, for example, the center of both the longitudinal and transverse directions of the light-emitting area Ld (a rectangle circumscribing the light-emitting area Ld), or the center of gravity of the light-emitting area Ld. For example, the light source 10A is positioned in contact with the iris diaphragm 21 or secured to the iris diaphragm 21 via a predetermined securing member. Furthermore, the light source 10B is positioned adjacent to the iris diaphragm 21, with the center of the second opening 21B aligned on its optical axis. The optical axis of the light source 10B is defined as the optical axis passing through the center of the light-emitting area of ​​the light source 10B. The center of the light-emitting area can be, for example, the center of both the longitudinal and transverse directions of the light-emitting area, or the center of gravity of the light-emitting area. For example, the light source 10B is positioned in contact with the iris diaphragm 21 or secured to the iris diaphragm 21 via a predetermined securing member.

[0060] In some embodiments, the light sources 10A and 10B are respectively arranged so that the diagonal direction of the substantially quadrilateral light emitting region is substantially consistent with the long side direction of the corresponding opening.

[0061] exist Figure 5 Schematically shows an example of arrangement of the light sources 10A and 10B relative to the iris diaphragm 21 according to the first embodiment. Figure 5 FIG. 2 shows an example of the arrangement of the light sources 10A and 10B when the iris diaphragm 21 is viewed from the condenser lens 23 side. Figure 5 In, with Figure 2 or Figure 4 The same parts are denoted by the same reference numerals, and the description thereof will be appropriately omitted.

[0062] The light source 10A is arranged so that the diagonal direction of the light-emitting area Ld is substantially aligned with the longitudinal direction of the first opening 21A formed in the iris diaphragm 21. The diagonal direction corresponds to the direction in which the diagonal line extends. The diagonal of the light-emitting area can be the diagonal of a quadrilateral region that inscribes or circumscribes the light-emitting area (e.g., a region that emits light with a predetermined intensity or greater). The longitudinal direction of the first opening 21A can be the longitudinal direction of the rectangle circumscribing the first opening 21A (e.g., the X direction).

[0063] For example, the light source 10A is arranged so that the center 21Aa of the first opening 21A formed in the iris diaphragm 21 is arranged on the optical axis passing through the center Lca of the light emitting area Ld, and the diagonal direction of the light emitting area is substantially consistent with the long side direction of the first opening 21A formed in the iris diaphragm 21. Figure 5 As shown, when the iris diaphragm 21 is viewed from the optical axis O, the light source 10A is arranged so that the center 21Aa of the first opening 21A coincides with the center Lca of the light emitting area.

[0064] Similarly, the light source 10B is arranged so that the diagonal direction of the light emitting area substantially coincides with the longitudinal direction of the second opening 21B formed in the iris diaphragm 21. The longitudinal direction of the second opening 21B may be the longitudinal direction of a rectangle circumscribing the second opening 21B (eg, the X direction).

[0065] For example, the light source 10B is arranged so that the center 21Ba of the second opening 21B formed in the iris diaphragm 21 is arranged on the optical axis passing through the center Lcb of the light emitting area, and the diagonal direction of the light emitting area is substantially consistent with the long side direction of the second opening 21B formed in the iris diaphragm 21. Figure 5 As shown, when the iris diaphragm 21 is viewed from the optical axis O, the light source 10B is arranged so that the center 21Ba of the second opening 21B coincides with the center Lcb of the light emitting area.

[0066] according to Figure 5 The structure shown in the figure maximizes the exposure of the light emitting area of ​​the light source 10A through the first opening 21A, and maximizes the exposure of the light emitting area of ​​the light source 10B through the second opening 21B, when the iris diaphragm 21 is viewed from the side of the condenser lens 23. This allows a greater amount of light to pass through the iris diaphragm 21. In particular, when the length of the long side of the opening formed in the iris diaphragm 21 is longer than the length of one side of the quadrilateral of the light emitting area of ​​the light source, as in FIG. Figure 5 As shown, by arranging the light source so that the long side direction of the opening is substantially aligned with the diagonal direction, the utilization efficiency of the light emitted by the light source can be improved.

[0067] exist Figure 2 In the embodiment, the iris diaphragm 21 is formed with a first opening 21A and a second opening 21B. However, the embodiment is not limited to the number of openings formed in the iris diaphragm 21. For example, the iris diaphragm 21 may have three or more openings. For example, the iris diaphragm 21 may have three or more openings formed in an arc shape centered on the optical axis O at approximately equal angular intervals. This allows illumination light to enter the eye approximately evenly from three or more incident positions.

[0068] (condenser lens 23)

[0069] The condenser lens 23 is a lens having refractive power in both the X and Y directions. The condenser lens 23 refracts the light from the light source 10A that has passed through the first opening 21A and guides it to the opening formed in the slit 22. The condenser lens 23 refracts the light from the light source 10B that has passed through the second opening 21B and guides it to the opening formed in the slit 22.

[0070] When the focal length of the condenser lens 23 is set to fc, as shown in FIG. Figure 3As shown, the iris stop 21 is arranged at the front focus position of the condenser lens 23 (ie, at a position separated from the condenser lens 23 by a focal distance fc).

[0071] The shape of the opening formed in the iris diaphragm 21 is Figure 5 In the case of an arcuate or rectangular shape as shown, the condenser lens 23 may be a toric lens, or a first cylindrical lens having a refractive power only in the Y direction (YZ plane) and a second cylindrical lens having a refractive power only in the X direction (XZ plane).

[0072] (Fissure 22)

[0073] like Figure 1 As shown, the slit 22 (specifically, an opening described later) is configured to be positioned at a conjugate position of the fundus of the eye E under examination, as an illumination aperture, illumination slit, or fundus slit, by aligning the eye E with the optical system. For example, an opening (a slit-shaped opening) is formed in the slit 22 in a direction corresponding to the direction of lines (rows) read out from the image sensor 51 described later using a rolling shutter method. In this embodiment, a rectangular opening is formed in the slit 22 with its long side in the X direction and its short side in the Y direction. The opening formed in the slit 22 defines the illumination pattern of the fundus Ef of the eye E under examination.

[0074] The slit 22 can be moved in the optical axis direction of the illumination optical system 20 by a moving mechanism (moving mechanism 22D, described later). The moving mechanism is controlled by the control unit 100, described later, to move the slit 22 in the optical axis direction. For example, the control unit 100 controls the moving mechanism in response to the state of the eye E. This allows the position of the slit 22 to be moved in response to the state of the eye E (specifically, the diopter and the shape of the fundus Ef).

[0075] In some embodiments, Figure 1 The light sources 10A, 10B, the iris diaphragm 21, the focusing lens 23, and the slit 22 shown are housed in an optical unit. The optical unit is configured to move in the optical axis direction of the illumination optical system 20. As a result, the above-mentioned optical elements are moved integrally in the optical axis direction of the illumination optical system 20. At this time, the moving mechanism (moving mechanism 22D described later) receives control from the control unit 100 described later and moves the above-mentioned optical unit in the optical axis direction. For example, the control unit 100 controls the moving mechanism in response to the state of the eye E to be examined. As a result, the position of the slit 22 included in the optical unit can be moved in response to the state of the eye E to be examined (specifically, the diopter, the shape of the fundus Ef).

[0076] In some embodiments, the slit 22 is configured to change at least one of the position and shape of the opening, rather than moving in the optical axis direction, in response to the state of the eye E. The function of the slit 22 is realized by, for example, a liquid crystal shutter.

[0077] (Relay lens system RL1)

[0078] like Figure 1 As shown, a relay lens system RL1 is disposed between the optical scanner 30 and the slit 22. The relay lens system RL1 includes one or more lenses. The rear focus position of the relay lens system RL1 is disposed at a conjugate position of the iris of the eye E to be examined.

[0079] As described later, the optical scanner 30, which is positioned at a conjugate position with the iris of the eye E, is positioned at or near the rear focus position of the relay lens system RL1. Therefore, when the slit 22 is moved along the optical axis in response to the state (diopter) of the eye E, the size of the slit image (the image formed by light passing through the opening formed in the slit 22) projected onto the fundus Ef does not change regardless of the state of the eye E. This means that even if the slit 22 is moved along the optical axis, the projection magnification of the slit image onto the fundus Ef does not change.

[0080] That is, by arranging the optical scanner 30 at the rear focus position of the relay lens system RL1 (or in the vicinity thereof), the relay lens system RL1, the relay lenses 41, 44 and the objective lens 46 constitute a Badal optical system (see Figure 1 ).

[0081] Thus, regardless of the state (diopter, etc.) of the examined eye E, the projection field angle (projection magnification) of the slit image relative to the visual axis of the examined eye E (in the long and short directions of the slit 22 ) can be kept constant. As a result, the size of the slit image does not change regardless of the state of the examined eye E, thereby making it possible to maintain a constant deflection operating speed of the optical scanner 30, thereby simplifying the control of the optical scanner 30 .

[0082] In addition, regardless of the state of the examined eye E (refractive power, etc.), the projection field angle (projection magnification) of the slit image relative to the visual axis of the examined eye E is constant, so the illumination of the slit image on the fundus Ef can be kept constant.

[0083] Furthermore, when an ophthalmologic apparatus acquires an image at a predetermined imaging angle of view, the projection magnification is constant as described above, so there is no need to provide a margin for the length in the longitudinal direction of the slit 22 provided to acquire a slit image of a predetermined size.

[0084] As described above, in the illumination optical system 20, light from the light source 10A, which has the highest luminous intensity region and has a light intensity distribution w0, passes through the first opening 21A formed in the iris diaphragm 21. Furthermore, light from the light source 10B, which has the highest luminous intensity region and has a light intensity distribution w0, passes through the second opening 21B formed in the iris diaphragm 21. The condenser lens 23 refracts the light that has passed through the first and second openings 21A and 21B and guides it toward the opening formed in the slit 22. The light guided to the slit 22 passes through the opening formed in the slit 22 and is output as slit-shaped illumination light. The slit-shaped illumination light is guided to the optical scanner 30 through the relay lens system RL1.

[0085] (Optical Scanner 30)

[0086] The optical scanner 30 is configured to be positioned at a conjugate position with the iris of the eye E, through alignment between the eye E and the optical system. 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 has passed through the relay lens system RL1. Specifically, the optical scanner 30 deflects the slit-shaped illumination light for sequentially illuminating a predetermined illumination range of the fundus Ef while changing the deflection angle within a predetermined deflection angle range, with the iris of the eye E or its vicinity as the scanning center position, and then guides the deflected light toward the projection optical system 35. The optical scanner 30 can deflect the illumination light in one or two dimensions.

[0087] When performing one-dimensional deflection, the optical scanner 30 includes a galvano scanner that deflects the illumination light within a predetermined deflection angle range based on a predetermined deflection direction. When performing two-dimensional deflection, the optical scanner 30 includes a first galvano scanner and a second galvano scanner. The first galvano scanner deflects the illumination light by shifting the illumination light's irradiation position in a horizontal direction perpendicular to the optical axis of the illumination optical system 20. The second galvano scanner deflects the illumination light deflected by the first galvano scanner by shifting the illumination light's irradiation position in a vertical direction perpendicular to the optical axis of the illumination optical system 20. Examples of scanning methods used by the optical scanner 30 to shift the illumination light's irradiation position include horizontal scanning, vertical scanning, cross scanning, radial scanning, circular scanning, concentric scanning, and spiral scanning.

[0088] (Projection optical system 35)

[0089] The projection optical system 35 guides the illumination light deflected by the optical scanner 30 to the fundus Ef of the inspected eye E. In the embodiment, the projection optical system 35 guides the illumination light deflected by the optical scanner 30 to the fundus Ef via an aperture mirror 45 as an optical path dividing member described later.

[0090] The projection optical system 35 includes a relay lens 41, a black spot plate 42, a reflection mirror 43, and a relay lens 44. Each of the relay lenses 41 and 44 includes one or more lenses.

[0091] (Black dot plate 42)

[0092] The black spot plate 42 is arranged at a position substantially optically conjugate with the lens surface of the objective lens 46 or its vicinity.

[0093] In the projection optical system 35 , the illumination light deflected by the optical scanner 30 passes through the relay lens 41 , passes through the black dot plate 42 , is reflected by the reflective mirror 43 toward the relay lens 44 , passes through the relay lens 44 , and is guided to the aperture mirror 45 .

[0094] (Photographic Optical System 40)

[0095] The imaging optical system 40 guides the illumination light guided by the projection optical system 35 to the fundus Ef of the eye to be examined E, and guides the return light from the eye to be examined E to the imaging device 50. The return light from the eye to be examined E is scattered light (reflected light) of the illumination light incident on the eye to be examined E. In some embodiments, the return light from the eye to be examined E includes scattered light (reflected light) of the illumination light incident on the eye to be examined E, and fluorescence excited by the illumination light incident on the eye to be examined E and its scattered light.

[0096] The imaging optical system 40 spatially divides the optical paths of the illumination light from the projection optical system 35 and the return light from the inspected eye E (fundus Ef). By using an aperture mirror 45 as an optical path dividing member for dividing these optical paths, pupil division can be performed on the illumination light and its return light.

[0097] The photographing optical system 40 includes an aperture lens 45, an objective lens 46, a focus lens 47, a relay lens 48, and an imaging lens 49. The relay lens 48 includes one or more lenses.

[0098] (Aperture Mirror 45)

[0099] The aperture mirror 45 is formed with an aperture portion aligned with the optical axis O1 of the imaging optical system 40. The aperture mirror 45 is configured so that, through alignment between the examinee's eye E and the optical system, the aperture portion is positioned at a conjugate position with the iris of the examinee's eye E. The aperture mirror 45 reflects illumination light from the projection optical system 35 toward the objective lens 46 in a region surrounding the aperture portion. This aperture mirror 45 functions as an imaging aperture.

[0100] Furthermore, the aperture mirror 45 functions as an optical path dividing member that spatially divides the optical path of the illumination light that has passed through the slit 22 and the optical path of the return light from the eye to be examined E.

[0101] exist Figure 6Schematically shows an image formed at the iris conjugate position Q on a plane intersecting the optical axis. Figure 6 For example, an image formed on the reflection surface of the aperture mirror 45 disposed at the iris conjugate position Q is schematically shown.

[0102] The aperture of the aperture mirror 45, which is arranged so that the optical axis O1 passes therethrough, forms an imaging aperture SA serving as a light-receiving aperture. Return light from the eye E to be examined passes through the imaging aperture SA. In the area surrounding the aperture of the aperture mirror 45, an image IA1 of the first aperture 21A and an image IA2 of the second aperture 21B of the iris diaphragm 21 are formed as illumination apertures.

[0103] That is, the aperture mirror 45 is configured to spatially divide the optical path of the illumination optical system 20 (projection optical system 35) and the optical path of the shooting optical system 40 arranged in the direction of the optical axis passing through the aperture portion, and to guide the illumination light reflected in the peripheral area of ​​the aperture portion to the fundus Ef.

[0104] (Focus lens 47)

[0105] The focus lens 47 can be moved in the optical axis direction of the imaging optical system 40 by a moving mechanism (not shown). The moving mechanism is controlled by the control unit 100, which will be described later, to move the focus lens 47 in the optical axis direction. In this way, it is possible to image the return light from the subject's eye E that has passed through the aperture of the aperture mirror 45 onto the light-receiving surface of the image sensor 51 of the imaging device 50 in response to the condition of the subject's eye E.

[0106] In such an imaging optical system 40, the illumination light from the projection optical system 35 is reflected toward the objective lens 46 at the peripheral area of ​​the aperture portion formed by the aperture mirror 45. The illumination light reflected at the peripheral area of ​​the aperture mirror 45 is refracted by the objective lens 46, passes through the pupil of the subject's eye E, enters the eye, and illuminates the fundus Ef of the subject's eye E.

[0107] The return light from the eye E is refracted by the objective lens 46 , passes through the aperture of the aperture mirror 45 , passes through the focus lens 47 , passes through the relay lens 48 , and is imaged by the imaging lens 49 onto the light receiving surface of the image sensor 51 of the imaging device 50 .

[0108] (Camera 50)

[0109] The imaging device 50 includes an image sensor 51 that receives return light guided from the fundus Ef of the eye E through the imaging optical system 40. The imaging device 50 can receive control from a control unit 100 described later to read out the result of receiving the return light.

[0110] (Image sensor 51)

[0111] 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 arranged at a position substantially optically conjugate with the fundus oculi Ef.

[0112] The light reception result of the image sensor 51 is controlled by a control unit 100 described later and read out by a rolling shutter method.

[0113] Such an image sensor 51 includes a CMOS image sensor. In this case, the image sensor 51 includes a plurality of pixel groups (light-receiving elements) arranged in the row direction and a plurality of pixels arranged in the column direction. Specifically, the image sensor 51 includes a plurality of pixels arranged in two dimensions, a plurality of vertical signal lines, and a horizontal signal line. Each pixel includes a photodiode (light-receiving element) and a capacitor. A plurality of vertical signal lines are provided in each pixel group in the column direction (vertical direction) orthogonal to the row direction (horizontal direction). Each vertical signal line is selectively electrically connected to a pixel group that has accumulated charges corresponding to the light-receiving results. The horizontal signal line is selectively electrically connected to a plurality of vertical signal lines. Each pixel accumulates charges corresponding to the light-receiving results of the return light, and the accumulated charges are read out, for example, sequentially to each pixel group in the row direction. For example, in each line in the row direction, a voltage corresponding to the charges accumulated in each pixel is supplied to the vertical signal line. A plurality of vertical signal lines are selectively electrically connected to the horizontal signal line. By sequentially performing the above-described readout operation for each line in the row direction in the vertical direction, it is possible to read out the light reception results of a plurality of pixels arranged two-dimensionally.

[0114] By collecting (reading out) the result of receiving the return light using a rolling shutter method on the image sensor 51, a received light image corresponding to a desired virtual aperture shape extending in the row direction is obtained. Such control is disclosed in, for example, US Patent No. 8,237,835.

[0115] exist Figure 7 2 is an explanatory diagram of the operation of the ophthalmologic apparatus 1 according to the embodiment. Figure 7 The irradiation range IP of the slit-shaped illumination light irradiated on the fundus oculi Ef and the virtual opening range OP in the light receiving surface SR of the image sensor 51 are schematically shown.

[0116] 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 irradiation range IP of the slit-shaped illumination light sequentially moves in a direction (e.g., vertical direction) perpendicular to the slit direction (e.g., row direction, horizontal direction) on the fundus Ef.

[0117] The control unit 100, described later, changes the pixels to be read on a line-by-line basis on the light-receiving surface SR of the image sensor 51, thereby setting a virtual aperture range OP. Preferably, the aperture range OP is the light-receiving range IP' of the return light on the light-receiving surface SR, or a range larger than the light-receiving range IP'. The control unit 100, described later, controls the movement of the aperture range OP in synchronization with the movement control of the illumination light irradiation range IP. This allows for the acquisition of high-quality images of the fundus Ef with high contrast, unaffected by unwanted scattered light, using a simple configuration.

[0118] exist Figure 8 and Figure 9 An example of the control timing of the rolling shutter method for the image sensor 51 is schematically shown in FIG. Figure 8 An example of the readout control timing for the image sensor 51 is shown. Figure 9 The movement control timing of the illumination light irradiation range IP (light receiving range IP') is Figure 8 The readout control timing is overlapped as shown in FIG. Figure 8 and Figure 9 In FIG. 5 , the vertical axis represents the number of rows of the image sensor 51 and the horizontal axis represents time.

[0119] In addition, Figure 8 and Figure 9 In the example, for the sake of convenience, the number of rows of the image sensor 51 is described as 1920, but the structure involved in the embodiment is not limited to the number of rows. Figure 9 In FIG. 1 , for convenience of explanation, it is assumed that the slit width (width in the row direction) of the slit-shaped illumination light is 40 lines.

[0120] The readout control in the row direction includes reset control, exposure control, charge transfer control, and output control. Reset control is a control that initializes the amount of charge accumulated in the pixels in the row direction. Exposure control is a control that irradiates light to the photodiode so that the charge corresponding to the amount of light received is accumulated in the capacitor. Charge transfer control is a control that transfers the charge accumulated in the pixel to the vertical signal line. Output control is a control that outputs the charge accumulated in multiple vertical signal lines via the horizontal signal line. That is, Figure 8 As shown, the readout time T of the charge amount accumulated in the pixels in the row direction is the sum of the time Tr required for reset control, the time Te required for exposure control (exposure time), the time Tc required for charge transfer control, and the time Tout required for output control.

[0121] exist Figure 8 In , by shifting the readout start timing (start timing of time Tc) in units of rows, the light reception results (charge amounts) accumulated by the pixels in the desired range in the image sensor 51 are obtained. Figure 8When the pixel range shown is one frame image, the frame rate FR is uniquely determined.

[0122] In the present embodiment, the irradiation position of the illumination light having a slit width corresponding to a plurality of rows on the fundus oculi Ef is sequentially shifted in a direction corresponding to the column direction on the fundus oculi Ef.

[0123] For example, Figure 9 As shown, the illumination position of the fundus Ef is shifted row-by-row in a direction corresponding to the column direction for each predetermined shift time Δt. The shift time Δt is obtained by dividing the exposure time Te of the pixels in the image sensor 51 by the slit width of the illumination light (e.g., 40) (Δt = Te / 40). In synchronization with the shift timing of the illumination position, the start of readout of each row of pixels is delayed by the shift time Δt for each row. This allows for the acquisition of high-contrast, high-quality images of the fundus Ef in a short period of time through simple control.

[0124] In some embodiments, the image sensor 51 is composed of more than one line sensor.

[0125] The slit 22 is an example of the “illumination aperture” according to the embodiment. The imaging optical system 40 is an example of the “light receiving optical system” according to the embodiment. The aperture mirror 45 is an example of the “optical path coupling member” according to the embodiment.

[0126] [Structure of the control system]

[0127] exist Figure 10 2 is a block diagram showing a configuration example of a control system (processing system) of the ophthalmologic apparatus 1 according to the embodiment.

[0128] The control system of the ophthalmologic apparatus 1 is configured centered around the control unit 100. In addition, the ophthalmologic apparatus 1 may include at least a part of the configuration of the control system.

[0129] (Control Unit 100)

[0130] The control unit 100 controls each unit of the ophthalmologic apparatus 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 executes processing according to a program stored in the storage unit 102 to control each unit of the ophthalmologic apparatus 1.

[0131] (Main control unit 101)

[0132] The main control unit 101 controls the illumination optical system 20 , the optical scanner 30 , the imaging optical system 40 , the imaging device 50 , and the data processing unit 200 .

[0133] Control of the illumination optical system 20 includes control of the light source 10 and control of the moving mechanism 22D. Control of the light source 10 includes switching on and off the light source (or the wavelength region of the light) and control of changes in the light amount of the light source. The moving mechanism 22D moves the slit 22 (or the above-mentioned optical unit) in the optical axis direction of the illumination optical system 20. The main control unit 101 controls the moving mechanism 22D in response to the state of the eye E to be examined, thereby configuring the slit 22 to a position corresponding to the state of the eye E to be examined. The state of the eye E includes the shape of the fundus Ef, the diopter, the axial length of the eye, etc. The diopter can be obtained from a known eye refractive power measuring device such as disclosed in Japanese Patent Application Laid-Open No. 61-293430 or Japanese Patent Application Laid-Open No. 2010-259495. The axial length of the eye can be obtained from a known axial length measuring device or from the measurement value of an optical coherence tomography scanner.

[0134] For example, the storage unit 102 stores first control information that preliminarily associates the position of the slit 22 on the optical axis of the illumination optical system 20 with the diopter. The main control unit 101 refers to the first control information to determine the position of the slit 22 corresponding to the diopter and controls the moving mechanism 22D to position the slit 22 at the determined position.

[0135] In some embodiments, as the slit 22 moves, the main control unit 101 changes the position and orientation of the light source 10 in accordance with changes in the light quantity distribution of light passing through the opening formed in the slit 22 .

[0136] Control of the optical scanner 30 includes control of the scanning range (scanning start position and scanning end position) and the scanning speed.

[0137] Control of the photographic optical system 40 includes control of the moving mechanism 47D. The moving mechanism 47D moves the focus lens 47 in the optical axis direction of the photographic optical system 40. The main control unit 101 can control the moving mechanism 47D based on the analysis results of the image acquired by the image sensor 51. Furthermore, the main control unit 101 can control the moving mechanism 47D based on the user's operation using the operation unit 110, which will be described later.

[0138] Control of the imaging device 50 includes control of the image sensor 51 (rolling shutter control). Control of the image sensor 51 includes reset control, exposure control, charge transfer control, and output control. Furthermore, the time Tr required for reset control, the time Te required for exposure control (exposure time), the time Tc required for charge transfer control, and the time Tout required for output control can be changed.

[0139] The data processing unit 200 controls 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 facilitate identification of predetermined areas depicted in the light reception image based on the light reception results. Analysis processing includes processes such as determining the focus state.

[0140] The data processing unit 200 can form a light-receiving image corresponding to any aperture range based on the light-receiving results read from the image sensor 51 using a rolling shutter method under the control of the main control unit 101 (control unit 100). The data processing unit 200 can sequentially form light-receiving images corresponding to the aperture range and form an image of the subject's eye E based on the multiple light-receiving images formed.

[0141] The data processing unit 200 includes a processor, and realizes the above-mentioned functions by performing processing according to a program stored in a storage unit or the like.

[0142] (Storage Unit 102)

[0143] The storage unit 102 stores various computer programs and data. The computer programs include a calculation program and a control program for controlling the ophthalmologic apparatus 1 .

[0144] (Operation unit 110)

[0145] The operating unit 110 includes an operating device or input device. The operating unit 110 may include buttons or switches (e.g., operating handles, operating knobs, etc.) provided on the ophthalmic apparatus 1, or operating devices (e.g., a mouse, keyboard, etc.). Furthermore, the operating unit 110 may include any operating device or input device, such as a trackball, operating panel, switch, button, dial, etc.

[0146] (Display unit 120)

[0147] The display unit 120 displays an image of the eye E generated by the data processing unit 200. The display unit 120 includes a display device such as a flat panel display (LCD) or similar. Alternatively, the display unit 120 may include various display devices such as a touch panel provided in the housing of the ophthalmic apparatus 1.

[0148] In addition, the operating unit 110 and the display unit 120 do not need to be configured as separate devices. For example, a device that integrates a display function and an operating function, such as a touch panel, can be used. In this case, the operating unit 110 is composed of the touch panel and a computer program. The operation content of the operating unit 110 is input to the control unit 100 as an electrical signal. In addition, a graphical user interface (GUI) displayed on the display unit 120 and the operating unit 110 can be used to perform operations or input information. In some embodiments, the functions of the display unit 120 and the operating unit 110 are implemented by a touch screen.

[0149] (Other structures)

[0150] In some embodiments, the ophthalmic device 1 further comprises a fixation projection system. For example, the optical path of the fixation projection system is Figure 1 The structure of the optical system shown is combined with the optical path of the shooting optical system 40. The fixation projection system can present an internal fixation mark or an external fixation mark to the eye E to be examined. When the eye E to be examined presents the internal fixation mark, the fixation projection system includes an LCD that receives control from the control unit 100 to display the internal fixation mark, and projects the fixation light beam output from the LCD to the fundus of the eye E to be examined. The LCD is configured to change the display position of the fixation mark on its screen. By changing the display position of the fixation mark on the LCD, the projection position of the fixation mark on the fundus of the eye E to be examined can be changed. The display position of the fixation mark on the LCD can be specified by the user using the operation unit 110.

[0151] 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 subject's eye 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 subject's eye E in the direction of the optical axis of the ophthalmic device 1 (objective lens 46).

[0152] For example, the XY alignment system projects a light spot (a light spot in the infrared or near-infrared region) onto the eye E. The data processing unit 200 acquires an image of the anterior segment of the eye E onto which the light spot is projected and calculates the displacement between the light spot image depicted in the acquired anterior segment image and the alignment reference position. The control unit 100 uses a movement mechanism (not shown) to relatively move the device optical system and the eye E in a direction intersecting the optical axis to eliminate the calculated displacement.

[0153] For example, the Z alignment system projects infrared or near-infrared aiming light from a position offset from the optical axis of the apparatus optical system and receives the aiming light reflected by the anterior segment of the examinee's eye E. The data processing unit 200 determines the distance of the examinee's eye E relative to the apparatus optical system based on the position where the aiming light is received, which changes in accordance with the distance of the examinee's eye E relative to the apparatus optical system. The control unit 100 uses a movement mechanism (not shown) to relatively move the apparatus optical system and the examinee's eye E in the direction of the optical axis so that the determined distance becomes the desired operating distance.

[0154] In some embodiments, the alignment system functions are implemented by two or more anterior ocular cameras positioned offset from the optical axis of the apparatus optical system. For example, as disclosed in Japanese Patent Application Laid-Open No. 2013-248376, the data processing unit 200 analyzes the anterior ocular images of the subject's eye E, acquired substantially simultaneously by the two or more anterior ocular cameras, and determines the three-dimensional position of the subject's eye E using a known triangulation method. The control unit 100 uses a movement mechanism (not shown) to move the apparatus optical system and the subject's eye E three-dimensionally relative to each other, so that the optical axis of the apparatus optical system and the axis of the subject's eye E are approximately aligned, and the distance between the apparatus optical system and the subject's eye E is adjusted to a predetermined operating distance.

[0155] [Work]

[0156] Next, an operation example of the ophthalmologic apparatus 1 will be described.

[0157] Figure 11 A flowchart showing an example of the operation of the ophthalmologic apparatus 1 according to the embodiment is shown. Figure 11 The main control unit 101 operates according to the computer program, thereby executing Figure 11 The processing shown.

[0158] Here, the alignment system (not shown) completes the alignment of the apparatus optical system with respect to the examinee's eye E, and the fixation projection system (not shown) projects a fixation mark onto the fundus of the examinee's eye E to guide it to a desired fixation position.

[0159] (S1: Obtain diopter)

[0160] First, the main control unit 101 obtains the refractive power of the eye to be examined E from an external ophthalmologic measurement device or an electronic medical record.

[0161] For example, the main control unit 101 acquires the refractive power of the eye to be examined E from an external ophthalmologic measurement device or an electronic medical record via a communication unit (not shown).

[0162] (S2: Change the location of the rift)

[0163] Next, the main control unit 101 changes the position of the slit 22 on the optical axis of the illumination optical system 20 based on the refractive power of the eye to be examined E acquired in step S1 .

[0164] Specifically, the main control unit 101 determines the position of the slit 22 corresponding to the diopter by referring to the first control information stored in the storage unit 102 , and controls the moving mechanism 22D so that the slit 22 is arranged at the determined position.

[0165] (S3: Illuminating light)

[0166] Next, the main control unit 101 generates slit-shaped illumination light using the illumination optical system 20 and starts deflection control of the optical scanner 30, thereby starting to irradiate the desired irradiation range on the fundus Ef with the illumination light. Once irradiation with the illumination light begins, the slit-shaped illumination light sequentially irradiates the desired irradiation range as described above.

[0167] (S4: Acquisition of light reception results)

[0168] As described above, the main control unit 101 acquires the light reception results of the pixels in the aperture range of the image sensor 51 corresponding to the irradiation range of the illumination light on the fundus oculi Ef executed in step S3 .

[0169] (S5: Next irradiation position?)

[0170] The main control unit 101 determines whether there is a next irradiation position to be irradiated with illumination light. The main control unit 101 determines whether the irradiation range of the sequentially shifted illumination light covers a predetermined imaging range of the fundus Ef, thereby determining whether there is a next irradiation position to be irradiated with illumination light.

[0171] If it is determined that there is a next irradiation position to be irradiated with illumination light (S5: Yes), the operation of the ophthalmologic apparatus 1 proceeds to step S3. If it is determined that there is no next irradiation position to be irradiated with illumination light (S5: No), the operation of the ophthalmologic apparatus 1 proceeds to step S6.

[0172] (S6: Image Formation)

[0173] When it is determined in step S5 that there is no next irradiation position to be irradiated with illumination light (S5: No), the main control unit 101 causes the data processing unit 200 to form an image of the eye E based on the light reception results repeatedly acquired while changing the irradiation range of the illumination light in step S4.

[0174] For example, based on the order in which the illumination range is shifted, the data processing unit 200 synthesizes a plurality of light reception results having different illumination ranges (the aperture range on the light receiving surface SR of the image sensor 51) corresponding to the number of repetitions of the processes of steps S3 to S5. This creates a single frame of a fundus image of the fundus Ef.

[0175] In some embodiments, in step S3, illumination light is irradiated onto the irradiation range set so as to form an overlapping region that overlaps with an adjacent irradiation range. Thus, in step S6, images are synthesized so that the overlapping regions overlap with each other, thereby forming a single frame of fundus image.

[0176] With the above, the operation of the ophthalmologic apparatus 1 is completed (End).

[0177] As described above, in the first embodiment, light sources 10A and 10B are positioned adjacent to the first and second openings 21A and 21B formed in the iris diaphragm 21, respectively. The center of the first opening 21A is positioned on the optical axis of light source 10A, and the center of the second opening 21B is positioned on the optical axis of light source 10B. Furthermore, light sources 10A and 10B are positioned so that the diagonal directions of their respective, generally quadrilateral light-emitting areas roughly align with the longitudinal directions of the corresponding openings. This reduces the amount of heat generated by each of the two or more light sources, allowing for bright illumination of the observation area with a simple configuration. In particular, by using a high-brightness light source, which increases brightness as the light-emitting area decreases, the efficiency of light utilization can be improved. For example, compared to a method where light from a light source is magnified and projected onto the iris diaphragm by lens or other means, sufficient illumination can be provided along the longitudinal directions of the openings formed in the slit. As a result, the size of the illumination openings can be increased, increasing the number of openings at the observation area and enabling clearer observation of the observation area.

[0178] <Second embodiment>

[0179] The structure of the ophthalmic apparatus according to the embodiment is not limited to that of Embodiment 1. For example, two or more light sources irradiating the iris diaphragm 21 may be disposed at positions substantially optically conjugate with corresponding openings of the two or more openings formed in the iris diaphragm 21 .

[0180] Hereinafter, the ophthalmologic apparatus according to the second embodiment will be described focusing on differences from the ophthalmologic apparatus 1 according to the first embodiment.

[0181] exist Figure 12 and Figure 13 , an example of the configuration of the optical system of the ophthalmologic apparatus according to the second embodiment is shown. Figure 12 In, with Figure 1 The same parts are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. Figure 13 It schematically shows the YZ plane Figure 12 FIG. 2 is a diagram showing the structure of the optical system of the illumination optical system 20a. Figure 13 In, with Figure 3 The same parts are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0182] like Figure 12 As shown, the configuration of the ophthalmologic apparatus 1a according to the second embodiment differs from the configuration of the ophthalmologic apparatus 1 according to the first embodiment in that an illumination optical system 20a is provided in place of the illumination optical system 20. The illumination optical system 20a differs from the illumination optical system 20 in that a relay lens 11A, a reflective member 12A, a relay lens 11B, and a reflective member 12B are additionally provided.

[0183] In the second embodiment, similar to the first embodiment, a light source 10A is provided corresponding to a first opening 21A formed in the iris diaphragm 21, and a light source 10B is provided corresponding to a second opening 21B formed in the iris diaphragm 21. A relay lens 11A and a reflective member 12A are disposed between the light source 10A and the first opening 21A. A relay lens 11B and a reflective member 12B are disposed between the light source 10B and the second opening 21B. Reflective members 12A and 12B can each be a mirror or a prism.

[0184] In the second embodiment, the light source 10A is arranged at a position substantially optically conjugate with the first opening 21A. The center of the first opening 21A is located on the optical axis of the light source 10A. The relay lens 11A transmits light emitted from the light source 10A and guides it to the reflective component 12A. The relay lens 11A includes one or more lenses. The reflective component 12A deflects the light transmitted through the relay lens 11A and guides it to the first opening 21A.

[0185] Similarly, light source 10B is configured to be positioned substantially optically conjugate with second opening 21B. The center of second opening 21B is positioned on the optical axis of light source 10B. Relay lens 11B transmits light emitted from light source 10B and guides it to reflective component 12B. Relay lens 11B includes one or more lenses. Reflective component 12B deflects light transmitted through relay lens 11B and guides it to second opening 21B.

[0186] In some embodiments, the relay lens 11A is disposed between the reflective component 12A and the first opening 21A, and the relay lens 11B is disposed between the reflective component 12B and the second opening 21B.

[0187] The operation of the ophthalmologic apparatus 1 a according to the second embodiment is similar to that of the ophthalmologic apparatus 1 according to the first embodiment, and therefore, description thereof will be omitted.

[0188] As described above, the second embodiment can achieve the same effects as the first embodiment, and can also increase the degree of freedom in the arrangement of the light sources 10A and 10B. For example, even when the interval between the first opening 21A and the second opening 21B is narrow or the light sources 10A and 10B are large, the efficiency of the light emitted by the light sources can be improved.

[0189] <Third embodiment>

[0190] The structure of the ophthalmic device according to the embodiment is not limited to that according to the above-described embodiment. For example, the device may be configured such that light emitted from two or more light sources that illuminate the iris diaphragm 21 is guided through a light guide member to corresponding openings among the two or more openings formed in the iris diaphragm 21.

[0191] Hereinafter, the ophthalmologic apparatus according to the third embodiment will be described focusing on differences from the ophthalmologic apparatus 1 according to the first embodiment.

[0192] exist Figure 14 and Figure 15 An example of the configuration of an optical system of an ophthalmologic apparatus according to a third embodiment is shown. Figure 14 In, with Figure 1 The same parts are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. Figure 15 It schematically shows the YZ plane Figure 14 FIG. 20 is a diagram showing the structure of the optical system of the illumination optical system 20b. Figure 15 In, with Figure 3 The same parts are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0193] like Figure 14 As shown in FIG. 1 , the configuration of the ophthalmologic apparatus 1 b according to the third embodiment differs from the configuration of the ophthalmologic apparatus 1 according to the first embodiment in that an illumination optical system 20 b is provided in place of the illumination optical system 20. The illumination optical system 20 b differs from the illumination optical system 20 in that a flexible light guide member 15A, a coupling lens 16A, and a lens 17A are additionally provided, as well as a flexible light guide member 15B, a coupling lens 16B, and a lens 17B.

[0194] In the third embodiment, similar to the first embodiment, light source 10A is provided corresponding to first opening 21A formed in iris diaphragm 21, and light source 10B is provided corresponding to second opening 21B formed in iris diaphragm 21. Coupling lens 16A, light guide member 15A, and lens 17A are disposed between light source 10A and first opening 21A. Coupling lens 16B, light guide member 15B, and lens 17B are disposed between light source 10B and second opening 21B.

[0195] Coupling lenses 16A and 16B can each be a cylindrical lens or a toric lens. Examples of light guide components 15A and 15B include optical fibers. In this case, the optical fibers can be configured to have a beam profile that changes the shape (beam cross-sectional shape) and NA of the emitted light, or they can be tapered with different NAs or core types on the incident and exit sides. Hereinafter, light guide components 15A and 15B are bundle-type optical fibers configured to change the shape of the emitted light according to the shape of the opening formed in the iris diaphragm 21.

[0196] If the focal length of coupling lens 16A is set to fcpl, the incident end of light guide component 15A is positioned at the rear focal position of coupling lens 16A. For example, the emission end of light guide component 15A is positioned substantially optically conjugate with first opening 21A. Lens 17A is positioned between the emission end of light guide component 15A and first opening 21A. Lens 17A includes one or more lenses. In some embodiments, lens 17A is a relay lens.

[0197] Similarly, if the focal length of coupling lens 16B is set to fcpl, the incident end of light guide component 15B is positioned at the rear focal position of coupling lens 16B. For example, the emission end of light guide component 15B is positioned substantially optically conjugate with second opening 21B. Lens 17B is positioned between the emission end of light guide component 15B and second opening 21B. Lens 17B includes one or more lenses. In some embodiments, lens 17B is a relay lens.

[0198] In the third embodiment as well, the center of the first opening 21A is arranged on the optical axis of the light source 10A, and the center of the second opening 21B is arranged on the optical axis of the light source 10B.

[0199] In the third embodiment, light from light source 10A is focused by coupling lens 16A onto the incident end of light guide member 15A. Light guide member 15A causes the light incident on the incident end to be emitted from the emission end. Light emitted from the emission end of light guide member 15A is refracted by lens 17A to pass through first opening 21A. Furthermore, light from light source 10B is focused by coupling lens 16B onto the incident end of light guide member 15B. Light guide member 15B causes the light incident on the incident end to be emitted from the emission end. Light emitted from the emission end of light guide member 15B is refracted by lens 17B to pass through second opening 21B.

[0200] The operation of the ophthalmologic apparatus 1 b according to the third embodiment is similar to that of the ophthalmologic apparatus 1 according to the first embodiment, and therefore, description thereof will be omitted.

[0201] As described above, the third embodiment achieves the same effects as the first embodiment, and further increases the degree of freedom in the placement of the light sources 10A and 10B relative to the opening formed in the iris diaphragm 21. For example, the light sources 10A and 10B can be placed at positions spaced apart from the opening formed in the iris diaphragm 21. This improves the efficiency of utilizing the light emitted by the light sources, even when the distance between the first opening 21A and the second opening 21B is narrow or the light sources 10A and 10B are large.

[0202] [effect]

[0203] An ophthalmologic apparatus according to an embodiment will be described.

[0204] A first mode of some embodiments is an ophthalmic device (1, 1a, 1b) including two or more light sources (light sources 10A, 10B), an illumination optical system (20, 20a, 20b), a light receiving optical system (photographing optical system 40), and an optical path dividing component (aperture mirror 45). The illumination optical system includes an iris aperture and an illumination aperture (slit 22), and uses the iris aperture and the illumination aperture to illuminate the eye (E) under examination with light from two or more light sources. The iris aperture is arranged at an iris conjugate position (Q) that is roughly optically conjugate with the iris of the eye under examination, and is formed with two or more openings (a first opening 21A and a second opening 21B). The illumination aperture is arranged at a fundus conjugate position (P) that is roughly optically conjugate with the fundus (Ef) of the eye under examination. The light receiving optical system guides the return light from the eye under examination to the imaging element (image sensor 51). The optical path dividing component spatially divides the optical path of the illumination optical system and the optical path of the light receiving optical system at a plane at the iris conjugate position so that the images of the two or more apertures are arranged around the light receiving aperture through which the return light passes. The centers of corresponding ones of the two or more apertures are arranged on the optical axes of the two or more light sources.

[0205] According to this method, the heat generated by each of the two or more light sources can be suppressed, and the observation area can be brightly illuminated with a simple structure. In particular, by using a high-brightness light source with a smaller luminous area and higher brightness, the utilization efficiency of the light source's luminous energy can be improved.

[0206] In a second aspect of some embodiments, according to the first aspect, the optical axis of the light source is an optical axis passing through the center of the light emitting area of ​​the light source.

[0207] According to this aspect, the light emitted from the center of the light emitting area can be used, thereby improving the efficiency of utilizing the amount of light emitted by the light source.

[0208] In a third aspect of some embodiments, according to the second aspect, a diagonal direction of the light-emitting region is substantially consistent with a long side direction of the corresponding opening.

[0209] According to this aspect, even when one side of the light emitting area of ​​the light source is shorter than the length of the opening formed in the iris diaphragm, the utilization efficiency of the light emitted by the light source can be improved.

[0210] In a fourth aspect of some embodiments, according to any one of the first to third aspects, the two or more light sources are respectively arranged at positions substantially optically conjugate with corresponding openings among the two or more openings.

[0211] This aspect can improve the degree of freedom in arranging the light source. For example, even when the interval between two or more openings formed in the iris diaphragm is narrow or the light source is large, the efficiency of utilizing the light emitted by the light source can be improved.

[0212] In a fifth aspect of some embodiments, according to any one of the first to third aspects, the system includes two or more light guide members (15A, 15B) that guide light emitted from the two or more light sources to corresponding openings among the two or more openings.

[0213] According to this aspect, the degree of freedom in arranging the light source relative to the opening formed in the iris diaphragm can be increased. For example, the light source can be arranged at a position separated from the opening formed in the iris diaphragm.

[0214] In a sixth aspect of some embodiments, according to the fifth aspect, the device includes two or more lenses (coupling lenses 16A, 16B) disposed between each of the two or more light sources and each of the two or more light guide members. An incident end of each of the two or more light guide members, into which outgoing light is incident, is disposed at a rear focal position of each of the two or more lenses.

[0215] According to this aspect, the light from the light source can be reliably guided to the opening formed in the iris diaphragm by the light guide member, and the efficiency of utilizing the amount of light emitted by the light source can be greatly improved.

[0216] In a seventh aspect of some embodiments, according to the fifth aspect, an emission end of the outgoing light guided by the light guide member is arranged at a position substantially optically conjugate with the corresponding opening.

[0217] According to this aspect, the light from the light source can be reliably guided to the opening formed in the iris diaphragm by the light guide member, and the efficiency of utilizing the amount of light emitted by the light source can be greatly improved.

[0218] In an eighth aspect of some embodiments, according to any one of the first to third aspects, two openings are formed in the iris diaphragm, and a position corresponding to the optical axis of the illumination optical system is arranged on a straight line connecting the centers of the two openings.

[0219] According to this aspect, pupil division can be performed with a simple structure, and the utilization efficiency of the light emission amount of the light source can be improved.

[0220] In a ninth aspect of some embodiments, according to any one of the first to third aspects, two or more openings (first opening 21A and second opening 21B) having an arcuate shape centered on the optical axis of the illumination optical system are formed in the iris diaphragm.

[0221] According to this aspect, pupil division can be performed with a simple structure, and the utilization efficiency of the light emission amount of the light source can be improved.

[0222] In a tenth aspect of some embodiments, according to the first to third aspects, a light scanner (30) is included that deflects light that has passed through an illumination aperture and guides the deflected illumination light to the fundus. A light reception result of the return light obtained by the imaging element is collected in synchronization with the deflection control of the light scanner.

[0223] According to such an aspect, a high-quality fundus image can be acquired with a simple configuration without being affected by unnecessary light of the illumination light.

[0224] In an eleventh aspect of some embodiments, according to the tenth aspect, the imaging element is an image sensor (51) of a rolling shutter type.

[0225] According to such a mode, a high-quality fundus image can be acquired through simple control without being affected by unnecessary light of the illumination light.

[0226] In a twelfth aspect of some embodiments, according to any one of the first to third aspects, a moving mechanism (22D) is included that moves the illumination aperture in the optical axis direction in response to the state of the eye to be examined.

[0227] According to such an aspect, regardless of the state of the eye to be examined, a high-quality fundus image can be acquired without being affected by unnecessary light of the illumination light.

[0228] The embodiment and its modified examples shown above are merely examples for implementing the present invention, and those who wish to implement the present invention may make arbitrary modifications, omissions, additions, etc. within the scope of the gist of the present invention.

[0229] In the above-mentioned embodiment, the ophthalmic device may have any function used in the field of ophthalmology, such as an axial length measurement function, an intraocular pressure measurement function, an optical interference tomography (OCT) function, an ultrasonic examination function, etc. In addition, the axial length measurement function is implemented by an optical interference tomography instrument, etc. In addition, the axial length measurement function can project light onto the inspected eye, while adjusting the position of the optical system relative to the Z direction (front-back direction) of the inspected eye, while detecting the return light from the fundus, thereby measuring the axial length of the inspected eye. The intraocular pressure measurement function is implemented by a tonometer, etc. The OCT function is implemented by an optical interference tomography instrument, etc. The ultrasonic examination function is implemented by an ultrasonic diagnostic device, etc. In addition, the present invention can also be applied to devices (compound machines) having two or more of these functions.

[0230] In some embodiments, a program is provided for causing a computer to execute the above-described method for controlling an ophthalmic device. Such a program can be stored in any non-transitory computer-readable storage medium. Examples of such storage media include semiconductor memories, optical disks, optical-magnetic disks (CD-ROM / DVD-RAM / DVD-ROM / MO, etc.), and magnetic storage media (hard disks / floppy disks (registered trademark) / ZIP, etc.). Furthermore, the program can be transmitted and received via a network such as the Internet or a LAN.

[0231] (Explanation of Reference Numerals)

[0232] 1, 1a, 1b: Ophthalmic devices

[0233] 10A, 10B: Light source

[0234] 11A, 11B: Relay lenses

[0235] 12A, 12B: Reflective components

[0236] 15A, 15B: Light guide components

[0237] 16A, 16B: coupling lenses

[0238] 17A, 17B: Lens

[0239] 20, 20a, 20b: Illumination optical system

[0240] 21: Iris aperture

[0241] 21A: First opening

[0242] 21B: Second opening

[0243] 22: Rift

[0244] 23: Focusing lens

[0245] 30: Optical Scanner

[0246] 35: Projection optical system

[0247] 40: Shooting Optical System

[0248] 45: Hole Mirror

[0249] 46: Objective lens

[0250] 50: Camera

[0251] 51: Image sensor

[0252] E: Eye under examination

[0253] Ef: Fundus

Claims

1. An ophthalmic device comprising: Two or more light sources; an illumination optical system comprising an iris diaphragm disposed at an iris conjugate position substantially optically conjugate with an iris of an eye to be examined and having two or more openings, and an illumination diaphragm disposed at a fundus conjugate position substantially optically conjugate with a fundus of the eye to be examined, the eye to be examined being illuminated by light from the two or more light sources by means of the iris diaphragm and the illumination diaphragm; a light receiving optical system for guiding return light from the eye to be examined to an imaging element; as well as an optical path dividing member that spatially divides the optical path of the illumination optical system and the optical path of the light receiving optical system on a plane at the iris conjugate position so that the images of the two or more openings are arranged around the light receiving opening through which the return light passes; The center of a corresponding opening among the two or more openings is arranged on the optical axis of each of the two or more light sources.

2. The ophthalmic device according to claim 1, wherein The optical axis of the light source is an optical axis passing through the center of the light emitting area of ​​the light source.

3. The ophthalmic device according to claim 2, wherein: The diagonal direction of the light emitting area is substantially consistent with the long side direction of the corresponding opening.

4. The ophthalmic device according to any one of claims 1 to 3, characterized in that The two or more light sources are respectively arranged at positions that are substantially optically conjugate with corresponding openings among the two or more openings.

5. The ophthalmic device according to any one of claims 1 to 3, characterized in that The ophthalmic device comprises: The two or more light guide components guide the emitted light of the two or more light sources to corresponding openings among the two or more openings.

6. The ophthalmic device according to claim 5, wherein: The ophthalmic device comprises: Two or more lenses are arranged between each of the two or more light sources and each of the two or more light guide components, The incident ends of the two or more light guide members, into which the outgoing light is incident, are arranged at the rear focal position of each of the two or more lenses.

7. The ophthalmic device according to claim 5, wherein An emission end of the outgoing light guided by the light guide member is arranged at a position substantially optically conjugate with the corresponding opening.

8. The ophthalmic device according to any one of claims 1 to 3, characterized in that There are two openings formed in the iris aperture. The position corresponding to the optical axis of the illumination optical system is arranged on a straight line connecting the centers of the two openings.

9. The ophthalmic device according to any one of claims 1 to 3, characterized in that The iris diaphragm has two or more openings formed therein, each having an arcuate shape centered on the optical axis of the illumination optical system.

10. The ophthalmic device according to any one of claims 1 to 3, characterized in that The ophthalmic device comprises: an optical scanner that deflects the light that has passed through the illumination aperture and guides the deflected illumination light to the fundus, The light reception result of the return light obtained by the imaging element is collected in synchronization with the deflection control of the optical scanner.

11. The ophthalmic device according to claim 10, wherein: The imaging element is a rolling shutter image sensor.

12. The ophthalmic device according to any one of claims 1 to 3, characterized in that The ophthalmic device comprises: The moving mechanism moves the illumination aperture in the optical axis direction in response to the state of the eye to be examined.

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