Ophthalmic devices

Abstract

To provide an ophthalmologic apparatus capable of executing observation and focus evaluation on an eye to be examined with a simple configuration.SOLUTION: An ophthalmologic apparatus 1 includes: a light source 21; a spectroscopic member 23 for spectroscopically separating light emitted from the light source 21; a first diaphragm 24 having a slit hole 241 to which each light emitted from the spectroscopic member 23 is radiated; a second diaphragm 25 having a plurality of split holes 251 disposed in a spectral direction of the spectroscopic member 23 for splitting the light emitted from the slit hole 241; an optical scanner 51 for guiding the light emitted from the second diaphragm 25 so as to move in an illumination area in an observed part of an eye E to be examined; a light reception system 3 having a detection part 33 for detecting return light Lb from the illumination area; a first focus optical system (26 and 29) for focusing the first diaphragm 24 and the observed part; and a second focus optical system 31 which is controlled so that the observed part and the detection part 33 are focused in conjunction with the focus of the first focus optical system.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to an ophthalmic device.

Background Art

[0002] Conventionally, a slit-scan type fundus camera (ophthalmic device) for photographing the fundus of an eye to be examined has been proposed. For example, in Patent Document 1, while moving the irradiation position of slit light (illumination light) irradiated onto the fundus using an optical scanner, the return light from the illumination region of the slit light moving within the fundus is imaged by a CMOS image sensor having a rolling shutter function. Thereby, a fundus image with reduced influence of scattered light can be obtained.

[0003] Further, Patent Document 2 describes an ophthalmic device that irradiates a split index image onto the fundus and performs evaluation and focusing control of the focusing state of the fundus camera based on a detection result obtained by detecting the return light of the split index light from the fundus with a detector.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the ophthalmic devices of Patent Document 1 and Patent Document 2, an illumination system for evaluating the focusing state and an illumination system for observing the eye to be examined are provided separately, and an increase in the size and cost of the entire device is assumed.

[0006] The present disclosure has been made to solve such problems, and an object thereof is to provide an ophthalmic device capable of observing an eye to be examined and evaluating focus with a simple configuration. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the ophthalmic device of the present disclosure comprises a light source, a spectroscopic element that disperses light emitted from the light source, a first aperture having slit holes onto which each light emitted from the spectroscopic element is irradiated, a second aperture having a plurality of dividing holes arranged in the spectroscopic direction of the spectroscopic element and dividing the light emitted from the slit holes, an optical scanner that guides the light emitted from the second aperture to a movably illuminated area at an observation site of the test eye, a light receiving system having a detection unit that detects returning light from the illumination area, a first focusing optical system that focuses the first aperture and the observation site, and a second focusing optical system that is controlled so that the observation site and the detection unit are focused in conjunction with the focusing of the first focusing optical system. [Effects of the Invention]

[0008] According to the ophthalmologic apparatus of the present disclosure using the above means, it is possible to observe the subject's eye and evaluate the focus with a simple configuration. [Brief explanation of the drawings]

[0009]

Figure 1

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Mode for Carrying Out the Invention

[0010] (Embodiment 1) Hereinafter, Embodiment 1 of the present disclosure will be described with reference to the drawings.

[0011] FIG. 1 is an overall configuration diagram of the ophthalmic apparatus 1 according to Embodiment 1. In FIG. 1, the X direction is the left-right direction (the eye width direction of the eye to be examined E) based on the subject, the Y direction is the up-down direction, and the Z direction is the front-rear direction (also referred to as the operating distance direction) which is the far-near direction with respect to the subject. Further, in the following description of the ophthalmic apparatus 1, each apparatus and the arrangement relationship are schematically shown and may be different from the actual scale for convenience of explanation.

[0012] The ophthalmic apparatus 1 can perform imaging of the fundus Ef of the eye to be examined E (slit-scan imaging) by the slit-scan method. The ophthalmic apparatus 1 includes a device main body 11 that functions as a camera head, an operation unit 12, a display unit 13, and a control device 14.

[0013] The device main body 11 is held by a drive mechanism (not shown) that can be manually or automatically moved in the X direction, Y direction, or Z direction with respect to the eye to be examined E. Therefore, the device main body 11 is configured to be relatively moved with respect to the eye to be examined E and alignment-adjustable.

[0014] The operation unit 12 can accept inputs for various operations of the ophthalmic apparatus 1, such as an operation to start slit scan photography, an operation to move the apparatus main body 11 relative to the subject's eye E, and an operation to set the ophthalmic apparatus 1.

[0015] A known display such as an LCD (Liquid Crystal Display) can be used as the display unit 13. The display unit 13 displays a fundus image, which is an observation image (front image) of the fundus Ef generated by the control device 14, as well as various setting screens.

[0016] The control device 14 is an arithmetic processing device such as a computer that executes various arithmetic processing and control processing. The device main body 11, the operation unit 12, and the display unit 13 are communicatively connected to the control device 14. The control device 14 comprehensively controls the operation of each unit of the device main body 11 and the display unit 13, for example, based on an operation instruction input to the operation unit 12. The control device 14 executes various controls and processes, including alignment of the device main body 11, focus confirmation control for capturing a focus evaluation image (see front view 5B1 in FIG. 5, etc.) that shows the focus state of the illumination system 2 and the light receiving system 3 with respect to the fundus Ef, focus control of the first focus optical system (first illumination side optical system 26 or second illumination side optical system 29) and the second focus optical system 31, slit scan photography of the fundus Ef by the device main body 11, and generation and display of a fundus image.

[0017] The following describes the configuration of the device body 11. The device body 11 includes an illumination system 2 and a light receiving system 3.

[0018] The illumination system 2 includes a light source 21, a plurality of lenses (a first illumination system lens 22, a first illumination side optical system 26, a second illumination system lens 27, a third illumination system lens 28, a second illumination side optical system 29, and an objective lens 53), a spectroscopic member 23, a first aperture 24, a second aperture 25, an optical scanner 51, and an optical path splitting member 52. The first aperture 24 and the site to be observed (for example, the fundus Ef) are in an optically conjugate relationship, and focusing is controlled by the control device 14 according to the relative positions of the ophthalmologic apparatus 1 and the subject's eye E and the position of the site to be observed in the subject's eye E.

[0019] The light source 21 emits illumination light Ls. When performing slit-scan imaging of the fundus Ef, the light source 21 emits visible light (for example, white light) as the illumination light Ls, and when performing focus confirmation control, the light source 21 emits near-infrared light (light in the infrared region) with low visual sensitivity of the eye to be examined E. The light source 21 may be composed of one or more light source elements. Note that visible light may also be used in the focus confirmation control. As the light source element used for the light source 21, a laser light emitting element, an LED (Light Emitting Diode), a fluorescent light emitting element, etc. can be used.

[0020] In this embodiment, the spectroscopic member 23 is a prism pair formed by combining two low-profile right-angled triangular prisms 23a. Each prism 23a is arranged close to or adjacent to each other in the X direction. Also, the prism 23a is formed with an incident surface 23a1 on the inclined surface corresponding to the hypotenuse of the bottom surface of the right-angled triangular prism, and an exit surface 23a2 on the surface perpendicular to the optical axis A corresponding to the adjacent side of the bottom surface of the right-angled triangular prism. The spectroscopic member 23 is formed with a concave incident side when viewed from the X direction in FIG. 1 such that the incident surfaces 23a1 of the two prisms 23a arranged in the X direction (the first prism arranged on one part side in the X direction and the second prism arranged on the other part side in the X direction) face the inside on the A-axis side. With such a configuration, the spectroscopic member 23 deflects a part of the second direction (a part on the front side in the X direction perpendicular to the optical axis A in FIG. 1) perpendicular to the first direction (the Y direction perpendicular to the optical axis A in FIG. 1) to one side of the first direction (the Y direction), and deflects the other part of the second direction (a part on the back side in the X direction perpendicular to the optical axis A in FIG. 1) to the other side of the first direction (the Y direction).

[0021] The first aperture 24 has a slit hole 241 onto which the respective lights emitted from the emission surfaces 23a2 of the respective prisms 23a in the spectroscopic member 23 are irradiated. The slit hole 241 is formed in a long rectangular shape (see Fig. 3). The slit hole 241 is arranged on the optical axis A so as to be long in the X direction. The first aperture 24 is located in an optically conjugate relationship, or a substantially optically conjugate relationship, with the observed site of the eye to be examined E (the fundus Ef in the example of Fig. 4).

[0022] The second aperture 25 has a plurality of divided holes 251 arranged in the spectroscopic direction of the spectroscopic member 23 (the Y direction in Fig. 1) and divides the light emitted from the slit hole 241 of the first aperture 24. The second aperture 25 is located in an optically conjugate relationship or a substantially conjugate relationship with the anterior eye segment Ea (cornea and lens) of the eye to be examined E, the optical scanner 51, and the optical path splitting member 52. Therefore, the conjugate position with respect to the first aperture 24 and the conjugate position with respect to the second aperture 25 are formed to be different. The divided holes 251 are arranged symmetrically with respect to the optical axis A, and in the present embodiment, they are arranged at two locations spaced apart in the Y direction of Fig. 1 (i.e., the spectroscopic direction of the spectroscopic member 23) (see also Fig. 3, etc.).

[0023] The first illumination-side optical system 26 and the second illumination system lens 27 collect the illumination light Ls emitted from the divided holes 251 of the second aperture 25 and guide it to the optical scanner 51.

[0024] The optical scanner 51 can be constituted by an optical element such as, for example, a galvanometer mirror, a resonant mirror, a polygon mirror, or a MEMS (Micro Electro Mechanical System), and has a deflecting function capable of guiding light. The optical scanner 51 one-dimensionally deflects (scans) the illumination light Ls incident from the second illumination system lens 27 on the light source 21 side and reflects it toward the subsequent third illumination system lens 28.

[0025] The deflection angle or deflection direction of the illumination light Ls deflected by the optical scanner 51 is controlled by the control device 14. Furthermore, during slit scan photography, the optical scanner 51 deflects the illumination light Ls in a direction (Y direction in FIG. 1) perpendicular to both the optical axis A (Z direction in FIG. 1) of the objective lens 53 and the long axis direction of the slit hole (X direction in FIG. 1). Therefore, the optical scanner 51 can guide the illumination light Ls emitted from the second aperture 25 to a movable illumination area at the observation site of the subject's eye E (for example, the fundus Ef).

[0026] The third illumination system lens 28 and the second illumination side optical system 29 condense the illumination light Ls emitted from the optical scanner 51 and guide it to the optical path splitting member 52 .

[0027] The optical path splitting member 52 is a so-called hole mirror, which is an annular reflective member having a substantially circular opening 521 inside for transmitting light. The optical path splitting member 52 reflects the illumination light Ls emitted from the second illumination side optical system 29 and emits it toward the objective lens 53, and also transmits the return light Lb emitted from the objective lens 53 and guides it to the light receiving system 3. Note that the optical path splitting member 52 may be an optical path splitting member formed of a mirror or splitter of another shape, as long as it can split the optical paths of the illumination light Ls and the return light Lb (i.e., it can guide the illumination light Ls toward the objective lens 53 on the side of the subject's eye E and guide the return light Lb to the light receiving system 3).

[0028] The objective lens 53 irradiates the illumination light Ls reflected by the optical path splitting member 52 onto a part of the fundus Ef through the anterior segment Ea (cornea and crystalline lens) of the subject's eye E. At this time, the illumination light Ls is deflected in the Y direction by the optical scanner 51 described above, so that the illumination light Ls (slit light) elongated in the X direction scans the fundus Ef in the Y direction. While the illumination light Ls is being deflected in the Y direction, return light Lb from the fundus Ef of the subject's eye E irradiated with the illumination light Ls is guided to the light receiving system 3 through the objective lens 53 and the optical path splitting member 52.

[0029] The light receiving system 3 includes an objective lens 53, an optical path splitting member 52, a second focusing optical system 31, a light receiving system lens 32, and a detection unit 33.

[0030] The second focusing optical system 31 includes one or a plurality of lenses (focus lenses) that are movable along the optical axis B of the return light Lb (the same axis as the optical axis A from the eye to be examined E to the optical path splitting member 52), and performs focus adjustment of the light receiving system 3 under the control of the control device 14. The focusing of the light receiving system 3 by the second focusing optical system 31 and the focusing of the illumination system 2 by the first focusing optical system (one or both of the first illumination side optical system 26 and the second illumination side optical system 29) are linked according to the diopter (visual power) of the eye to be examined E. The return light Lb incident on the second focusing optical system 31 from the optical path splitting member 52 is incident on the light receiving system lens 32. Instead of providing one or a plurality of focus lenses movably in the second focusing optical system 31, one or a plurality of variable focus lenses may be provided, and the method of focus adjustment is not particularly limited.

[0031] The light receiving system lens 32 is composed of one or a plurality of lenses, and condenses the return light Lb emitted from the second focusing optical system 31 onto the detection unit 33.

[0032] For example, a CMOS image sensor is used for the detection unit 33. The detection unit 33 has a light receiving surface 33a on which the return light Lb from the light receiving system lens 32 is incident, and has a rolling shutter function of imaging (receiving light, detecting) the return light Lb while shifting the timing of start and end of exposure for each region (including each pixel and each line) within the light receiving surface 33a. During slit-scan imaging, the detection unit 33 is driven by the rolling shutter by the control device 14 to image the return light Lb of the illumination light Ls that moves within the fundus Ef in accordance with the deflection of the illumination light Ls by the optical scanner 51, and outputs an imaging signal of the return light Lb to the control device 14.

[0033] FIG. 2 is a functional block diagram of the control device 14. The functions of the control device 14 are realized using various processors. The various processors include a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), and programmable logic devices (e.g., SPLD (Simple Programmable Logic Devices), CPLD (Complex Programmable Logic Device), and FPGA (Field Programmable Gate Arrays)). Note that the various functions of the control device 14 may be realized by one processor, or may be realized by a plurality of processors of the same type or different types.

[0034] The control device 14 functions as an illumination control unit 141, a deflection control unit 142, an imaging control unit 143, a signal acquisition unit 144, an image generation unit 145, a focus confirmation control unit 146, a repetition control unit 147, a focus control unit 148, and a display control unit 149 by executing a control program (not shown). Note that each functional unit of the control device 14 can be configured by software, hardware, or a combination thereof, by a program, a circuit, a device, or an apparatus.

[0035] Next, the optical path of the illumination system 2 will be described. FIG. 3 is a schematic optical path diagram of the illumination system 2 showing the optical path focused on the illumination light Ls (Ls11, Ls12) passing through the second aperture 25. A plan view 2-1 is shown in the upper part, and a side view 2-2 is shown in the middle part. The illumination light Ls emitted from the light source 21 and condensed by the first illumination system lens 22 is split by the beam splitter 23 into a plurality of split components in which a part in the X direction is deflected to one side in the Y direction and another part in the X direction is deflected to the other side in the Y direction (hereinafter, the split components guided with the split hole 251 of the second aperture 25 as the object point position are described as the first component lights Ls11, Ls12, and the split components guided with the slit hole 241 of the first aperture 24 as the object point position are described as the second component lights Ls21, Ls22).

[0036] In the illumination system 2, the positions of the second aperture 25, the optical scanner 51, the optical path splitting member 52, and the anterior eye part Ea are in a substantially optically conjugate relationship with each other. The first component lights Ls11 and Ls12 guided by the first illumination-side optical system 26 and the second illumination system lens 27 are substantially imaged on the reflecting surface of the optical scanner 51 and reflected by the optical scanner 51 toward the third illumination system lens 28. Thereafter, the first component lights Ls11 and Ls12 are guided to the optical path splitting member 52 by the third illumination system lens 28 and the second illumination-side optical system 29, are substantially imaged on the annular reflecting surface of the optical path splitting member 52, and are reflected by this reflecting surface toward the objective lens 53. The first component lights Ls11 and Ls12 condensed by the objective lens 53 are imaged on the anterior eye part Ea and then irradiated onto the fundus Ef.

[0037] Note that in FIG. 3 (the same applies to FIGS. 4, 7, and 8), below the side view 2-2, there are a plan view of each optical member (the first aperture 24, the second aperture 25, the optical scanner 51, and the optical path splitting member 52) (a view seen in the direction of the optical axis A for the first aperture 24 and the second aperture 25), and the cross-sectional shapes of the illumination light Ls (the second component lights Ls21 and Ls22) at a plurality of different optical path cross-sectional positions S1 to S3.

[0038] 4 is a schematic diagram of the optical path of the illumination system 2, focusing on the illumination light Ls (Ls21, Ls22) passing through the first aperture 24. In the illumination system 2, the positions of the first aperture 24 and the fundus oculi Ef (the observed area) are in a substantially optically conjugate relationship with each other. The second component lights Ls21, Ls22 emitted from the second aperture 25 are guided by the first illumination side optical system 26 and the second illumination system lens 27 while re-forming an image between them, and are reflected by the optical scanner 51 toward the third illumination system lens 28. Thereafter, the second component lights Ls21, Ls22 are guided by the third illumination system lens 28 and the second illumination side optical system 29 toward the optical path splitting member 52 while re-forming an image between them, and are reflected by the reflecting surface of the optical path splitting member 52 toward the objective lens 53. The second component lights Ls21 and Ls22 are also re-imaged between the optical path splitting member 52 and the objective lens 53. The second component lights Ls21 and Ls22 collected by the objective lens 53 are collected at the anterior segment Ea and then irradiated onto the fundus Ef. At the fundus Ef, the second component lights Ls21 and Ls22 are approximately re-imaged. In this way, the illumination system 2 can irradiate a part of the fundus Ef, which is the observation site, with the illumination light Ls (slit light) via the optical scanner 51.

[0039] Note that Figure 4 shows the optical path in which the illumination system 2 is in a focused state, but since the position of the subject's eye E may differ each time the ophthalmic device 1 is used, the ophthalmic device 1 can adjust the focused state using the focus confirmation control and focus control described below.

[0040] (Focus confirmation control and focus control) First, we will explain the functions related to focus confirmation control and focus control of the control device 14. In this embodiment, the focus state of the illumination system 2 and the light receiving system 3 relative to the fundus Ef is evaluated before slit scan photography of the fundus Ef by the ophthalmologic apparatus 1. In evaluating the focus state, attention is paid to the fact that the incidence state of the illumination light Ls on the fundus Ef changes between a state in which the illumination system 2 and the light receiving system 3 are focused on the fundus Ef (in focus) and a state in which the illumination system 2 and the light receiving system 3 are not focused on the fundus Ef (out of focus).

[0041] FIG. 5 shows side views 5A1 to 5A3 of the periphery of the eye E to be examined showing the optical path of the illumination light Ls at the time of focusing and defocusing, and front views 5B1 to 5B3 of the fundus Ef of the eye E to be examined irradiated with the illumination light Ls as seen from the front (P direction).

[0042] As shown in the side view 5A1, at the time of focusing, since the condensing positions of the light beams of the respective spectroscopic components (second component lights Ls21, Ls22) coincide (including substantially coincide) with the fundus Ef, in the front view 5B1, each of the second component lights Ls21, Ls22 on one side has substantially the same position in the Y direction (the scanning direction of the optical scanner 51), and the illumination light Ls in which the second component lights Ls21, Ls22 are imaged in a slit-shaped illumination region R1 in the X direction is irradiated (see also the front view 5B1 of FIG. 5). On the other hand, as shown in the side views 5A2, 5A3 and the front views 5B2, 5B3, at the time of defocusing, since the condensing positions of the light beams of the respective spectroscopic components (second component lights Ls21, Ls22) are shifted back and forth (in the direction of the optical axis A) with respect to the fundus Ef, each spectroscopic light is irradiated in two regions on the fundus Ef separated (shifted) in the Y direction.

[0043] For example, when the illumination light Ls is imaged in front of the fundus Ef as shown in the side view 5A2, as shown in the front view 5B2, compared with the time of focusing (front view 5B1), one of the second component lights Ls21 is irradiated downward and the other second component light Ls22 is irradiated upward. On the other hand, when the illumination light Ls is imaged behind the fundus Ef as shown in the side view 5A3, as shown in the front view 5B3, compared with the time of focusing (front view 5B1), one of the second component lights Ls21 is irradiated upward and the other second component light Ls22 is irradiated downward. And the amount of deviation (the amount of deviation in the direction of the optical axis A) of the imaging positions of the second component light Ls21 and the second component light Ls22 with respect to the fundus Ef can be evaluated by the amount of deviation in the Y direction of the second component light Ls21 and the second component light Ls22 in the front views 5B1 to 5B3.

[0044] More specifically, with the deflection angle of the illumination light Ls by the optical scanner 51 fixed, the control device 14 executes focus confirmation control for imaging, by the detection unit 33, the return light Lb from the fundus Ef irradiated with the illumination light Ls, and acquires a focus evaluation image indicating the focused state (for example, an image including the region of the fundus Ef shown in the front views 5B1 to 5B3). Then, based on the focus evaluation image acquired by the focus confirmation control, the control device 14 executes focus control for the first focus optical system (one or both of the first illumination-side optical system 26 and the second illumination-side optical system 29) and the second focus optical system 31.

[0045] The focus confirmation control and the focus control are mainly performed by the illumination control unit 141, the deflection control unit 142, the imaging control unit 143, the signal acquisition unit 144, the image generation unit 145, the focus confirmation control unit 146, the repetition control unit 147, and the focus control unit 148 of the control device 14 shown in FIG. 2.

[0046] The illumination control unit 141 emits the illumination light Ls (for example, near-infrared light) from the illumination system 2 during the focus confirmation control. When near-infrared light is used as the illumination light Ls, miosis of the eye E to be examined can be reduced.

[0047] The focus confirmation control unit 146 controls the optical scanner 51 via the illumination control unit 141 and controls the detection unit 33 via the imaging control unit 143 to execute shooting of a focus evaluation image (see the front views 5B1 to 5B3 in FIG. 5) (focus confirmation control). For example, the focus confirmation control unit 146 controls and fixes the deflection angle of the illumination light Ls by the optical scanner 51 so that the illumination light Ls is irradiated to the central region in the Y direction (including the substantially central region) of the fundus Ef by the deflection control unit 142.

[0048] The signal acquisition unit 144 sequentially acquires imaging signals output from the light receiving region of the detection unit 33 while the rolling shutter drive of the detection unit 33 is being performed during the focus confirmation control.

[0049] During the focus confirmation control, the image generation unit 145 generates a focus evaluation image indicating the in-focus state (an image including the region of the fundus Ef shown in front views 5B1 to 5B3) based on the imaging signal acquired by the signal acquisition unit 144 while the rolling shutter drive of the detection unit 33 is being performed. As described above with reference to FIG. 5, in the focus evaluation image generated at the time of focusing (see front view 5B1), the illumination light Ls is detected as one pattern image, and in the focus evaluation images generated at the time of out-of-focus (see front views 5B2 and 5B3), the illumination light Ls is detected as a spread or separated pattern image.

[0050] The repetition control unit 147 executes repetition control for repeatedly operating the focus confirmation control unit 146, the signal acquisition unit 144, and the image generation unit 145 for each of a plurality of different lens positions while changing the lens positions of the focus lenses of the first focus optical system (one or both of the first illumination side optical system 26 and the second illumination side optical system 29) and the second focus optical system 31. Thereby, focus evaluation images for each of the plurality of lens positions are generated. When the first focus optical system (one or both of the first illumination side optical system 26 and the second illumination side optical system 29) and the second focus optical system 31 are provided with variable focus lenses instead of focus lenses, the repetition control unit 147 executes repetition control for each of a plurality of different focal positions of the variable focus lenses.

[0051] The focusing control unit 148 performs focusing control of the first focus optical system (one or both of the first illumination side optical system 26 and the second illumination side optical system 29) and the second focus optical system 31 to focus the illumination system 2 and the light receiving system 3 on the fundus Ef. As described above, the focusing of the light receiving system 3 by the second focus optical system 31 and the focusing of the illumination system 2 by the first focus optical system move in conjunction with each other according to the diopter (visual acuity) of the subject's eye E. First, the focusing control unit 148 determines the focus evaluation image captured when the illumination system 2 and the light receiving system 3 are most focused on the fundus Ef from among the focus evaluation images for each lens position of the focus lens (including each focal position of the variable-focus lens; the same applies below) generated by the repeated control. For example, the focusing control unit 148 performs the above determination by comparing the Y-direction positional deviations of the pattern images of the second component light Ls21 and Ls22 included in the focus evaluation images for each lens position. Next, the focusing control unit 148 controls the first focus optical system (one or both of the first illumination side optical system 26 and the second illumination side optical system 29) and the second focus optical system 31 to move the focus lens to a lens position where the second component lights Ls21 and Ls22 are the same in the Y direction.

[0052] In this way, the first focusing optical system focuses the first aperture 24 and the observed region of the subject's eye E (the fundus Ef in this embodiment), and the second focusing optical system 31 controls the observation region and the detection unit to be focused in conjunction with the focusing of the first focusing optical system. The control device 14 can evaluate the focusing state based on the direction and amount of shift of the position of the illumination region by having the detection unit 33 detect the position of the illumination region of the illumination light Ls (second component light Ls21, Ls22) with respect to the fundus Ef, and can control the focusing.

[0053] (Slit scan photography) Next, slit-scan imaging will be described. In slit-scan imaging, mainly, the illumination control unit 141, deflection control unit 142, imaging control unit 143, signal acquisition unit 144, image generation unit 145, and display control unit 149 in the control device 14 function. FIG. 6 shows side views 6A1 to 6A3 of the periphery of the eye E to be examined showing the optical path of the illumination light Ls during slit-scan imaging, and front views 6B1 to 6B3 of the fundus Ef of the eye E to be examined irradiated with the illumination light Ls as seen from the front (P direction).

[0054] The illumination control unit 141 controls the emission of the illumination light Ls from the light source 21 (i.e., the illumination system 2). This illumination control unit 141 emits visible light as the illumination light Ls from the light source 21 during slit-scan imaging.

[0055] The deflection control unit 142 controls the deflection angle of the illumination light Ls by the optical scanner 51. This deflection control unit 142 controls the optical scanner 51 during slit-scan imaging to deflect the illumination light Ls in the Y direction, thereby scanning the fundus Ef in the Y direction (for example, from top to bottom), which is the width direction of the slit light, with the illumination light Ls (slit light).

[0056] The illumination region R1 of the illumination light Ls moves in the Y direction within the fundus Ef (the site to be observed) according to the deflection of the illumination light Ls in the Y direction (see also side views 6A1, 6A2 and front views 6B1, 6B2 in FIG. 6). Also, according to the movement of this illumination region R1, the incident region of the return light Lb within the light receiving surface 33a also moves in the Y direction.

[0057] The imaging control unit 143 controls the driving of the detection unit 33. This imaging control unit 143 causes the detection unit 33 to perform rolling shutter driving during slit-scan imaging while the illumination light Ls is being deflected in the Y direction by the optical scanner 51 (i.e., while the illumination region R1 is moving in the Y direction within the fundus Ef).

[0058] Specifically, the imaging control unit 143 continuously performs imaging of the return light Lb by this light-receiving area while causing the light-receiving area to follow the incident area (details not shown) of the return light Lb that moves in the Y direction within the light-receiving surface 33a. In other words, with respect to the movement of the illumination area R1 that moves in the Y direction within the fundus Ef, imaging of the illumination area R1 is continuously performed while the detection unit 33 locally follows the imaging range. Since such rolling shutter driving can use known techniques, detailed description thereof is omitted.

[0059] The signal acquisition unit 144 is wired-connected or wirelessly connected to the detection unit 33 via a communication interface (not shown). During slit-scan imaging, the signal acquisition unit 144 sequentially acquires an imaging signal (also referred to as a detection signal or a light-receiving signal) from the light-receiving area of the detection unit 33 while the illumination light Ls is being deflected by the optical scanner 51.

[0060] During the slit-scan imaging described above, the image generation unit 145 can generate a fundus image based on the imaging signal acquired by the signal acquisition unit 144 while the illumination light Ls is being deflected by the optical scanner 51.

[0061] The display control unit 149 controls the display by the display unit 13. For example, during slit-scan imaging, the display control unit 149 causes the display unit 13 to display the fundus Ef image generated by the image generation unit 145.

[0062] (Embodiment 2) Next, Embodiment 2 of the present disclosure will be described. In Embodiment 2, in the ophthalmic apparatus 1 of Embodiment 1, an illumination system 2A with a different configuration is used instead of the illumination system 2. FIG. 7 is a schematic optical path diagram of the illumination system 2A showing the illumination light Ls (Ls11, Ls12) passing through the second aperture 25. Similar to FIG. 3 described above, a plan view 2A-1 is shown in the upper part of FIG. 7, and a side view 2A-2 is shown in the middle part. FIG. 8 is a schematic optical path diagram of the illumination system 2A showing the illumination light Ls (Ls21, Ls22) passing through the first aperture 24. In the description of Embodiment 2, components having the same configuration as those of the illumination system 2 in Embodiment 1 are denoted by the same reference numerals, and the description thereof is omitted or simplified.

[0063] In the illumination system 2A, unlike the illumination system 2, the arrangement of the second illumination system lens 27 is omitted between the second aperture 25 and the optical scanner 51. Therefore, the illumination system 2dA can be simply configured.

[0064] (Modification 1) Next, a modification of the illumination systems 2 and 2A will be described. The light source 21A shown in FIG. 9 is a diagram showing the configuration of Modification 1 that can be applied instead of the light source 21 described in Embodiment 1 and Embodiment 2. The light source 21A includes a near-infrared light source element 211 that emits near-infrared light, a visible light source element 212 that emits white light as visible light, and a dichroic mirror 213 that guides each light emitted from the near-infrared light source element 211 and the visible light source element 212 to the same optical path. The dichroic mirror 213 transmits the illumination light Ls emitted from the near-infrared light source element 211 and makes it incident on the first illumination system lens 22, and reflects the illumination light Ls emitted from the visible light source element 212 and makes it incident on the first illumination system lens 22.

[0065] Note that the arrangement of the near-infrared light source element 211 and the visible light source element 212 is not limited to the configuration of the light source 21A. For example, the arrangement of the near-infrared light source element 211 and the visible light source element 212 may be interchanged, and the dichroic mirror 213 may reflect the illumination light Ls emitted from the near-infrared light source element 211, transmit the illumination light Ls emitted from the visible light source element 212, and make each illumination light Ls incident on the first illumination system lens 22.

[0066] By using the light source 21A of Modification 1, the lighting systems 2 and 2A can easily control the emission timing and intensity of near-infrared light and visible light.

[0067] (Modification 2) The light source 21B shown in FIG. 9 is a diagram showing the configuration of Modification 2 applicable instead of the light source 21 described in Embodiment 1 and Embodiment 2. The light source 21B includes a near-infrared light source element 211 that emits near-infrared light, a plurality of visible light source elements (a red light source element 214, a green light source element 215, and a blue light source element 216) that emit visible light, and a plurality of dichroic mirrors (a first dichroic mirror 217a, a second dichroic mirror 217b, and a third dichroic mirror 217c) that guide each light emitted from each visible light source element to the same optical path as the light emitted from the near-infrared light source element 211.

[0068] The red light source element 214, the green light source element 215, and the blue light source element 216 each emit red light, green light, and blue light as illumination light Ls. The first dichroic mirror 217a transmits the near-infrared light emitted from the near-infrared light source element 211 and makes it incident on the second dichroic mirror 217b, and reflects the red light emitted from the red light source element 214 and makes it incident on the second dichroic mirror 217b. The second dichroic mirror 217b transmits the near-infrared light and the red light and makes them incident on the third dichroic mirror 217c, and reflects the green light emitted from the green light source element 215 and makes it incident on the third dichroic mirror 217c. Further, the third dichroic mirror 217c transmits the near-infrared light, the red light, and the green light and makes them incident on the first illumination system lens 22, and reflects the blue light emitted from the blue light source element 216 and makes it incident on the first illumination system lens 22.

[0069] Note that the arrangement of each light source element 211, 214 to 216 is not limited to the configuration of the light source 21B. For example, some or all of the arrangements of the near-infrared light source element 211, the red light source element 214, the green light source element 215, and the blue light source element 216 may be interchanged, and a plurality of dichroic mirrors may be arranged so that the illumination light Ls emitted from each light source element 211, 214 to 216 is guided along the same optical path, and each illumination light Ls may be configured to be incident on the first illumination system lens 22.

[0070] By using the light source 21B of the second modification, the illumination systems 2 and 2A can easily control the emission timing and intensity of near-infrared light and visible light, and can also easily adjust wavelength components such as the white balance of visible light (white light).

[0071] (Second Modification) The light source 21C shown in FIG. 10 is a diagram showing a configuration of a third modification applicable in place of the light source 21 described in the first and second embodiments. The light source 21C includes a near-infrared light source element 211, a plurality of visible light source elements (a red light source element 214, a green light source element 215, and a blue light source element 216), a dichroic prism 218, and a dichroic mirror 213.

[0072] The dichroic prism 218 reflects the red light and the blue light respectively emitted as the illumination light Ls from the red light source element 214 and the blue light source element 216 and emits them toward the dichroic mirror 213. The dichroic prism 218 also transmits the green light emitted as the illumination light Ls from the green light source element 215 and emits it toward the dichroic mirror 213. Therefore, the dichroic prism 218 guides the respective lights emitted from the red light source element 214, the green light source element 215, and the blue light source element 216 along the same optical path. The dichroic mirror 213 transmits the near-infrared light and makes it incident on the first illumination system lens 22, and reflects the red light, the green light, and the blue light guided by the dichroic prism 218 and makes them incident on the first illumination system lens 22. Therefore, the dichroic mirror 213 guides the respective lights emitted from the dichroic prism 218 along the same optical path as the light emitted from the near-infrared light source element 211.

[0073] Note that the arrangement of each light source element 211, 214 to 216 is not limited to the configuration of the light source 21C. For example, the arrangement of one or both of the near-infrared light source element 211 and the red light source element 214, the green light source element 215, and the blue light source element 216 is interchanged, and the dichroic prism 218 and the dichroic mirror 213 are arranged so that the illumination light Ls emitted from each light source element 211, 214 to 216 is guided in the same optical path, and each illumination light Ls may be configured to be incident on the first illumination system lens 22.

[0074] By using the light source 21C of the third modification, the illumination systems 2 and 2A can easily control the emission timing and intensity of the near-infrared light and the visible light, and can also easily adjust the wavelength components such as the white balance of the visible light (white light) with a smaller configuration.

[0075] As described above, in the present embodiment, the ophthalmic apparatus 1 includes a light source 21, a spectroscopic member 23 that spectroscopically splits the light emitted from the light source 21, a first diaphragm 24 having a slit hole 241 irradiated with each light emitted from the spectroscopic member 23, a second diaphragm 25 having a plurality of split holes 251 arranged in the spectroscopic direction of the spectroscopic member 23 and splitting the light emitted from the slit hole 241, an optical scanner 51 that movably guides the light emitted from the second diaphragm 25 to the illumination region R1 at the observation site of the eye to be examined E, a light receiving system 3 having a detection unit 33 that detects the return light Lb from the illumination region R1, a first focus optical system (26, 29) that focuses the first diaphragm 24 and the observation site, and a second focus optical system 31 that is controlled so that the observation site and the detection unit 33 are focused in conjunction with the focusing of the first focus optical system (26, 29). The configuration of the ophthalmic apparatus 1 has been described.

[0076] With such a configuration, it is possible to use the slit-shaped light guided through the common illumination system 2 as both illumination light and light for phase difference focusing. Therefore, an ophthalmic apparatus 1 capable of observing and evaluating focus of the eye to be examined E with a simple configuration can be configured.

[0077] The description of the embodiments of the present disclosure ends above, but the aspects of the present disclosure are not limited to the configurations shown in each embodiment.

[0078] For example, in Embodiments 1 and 2, the split holes 251 of the second aperture 25 are illustrated as being arranged at two positions spaced apart in the Y direction (i.e., the spectral splitting direction of the spectral splitting member 23) in FIG. 1. However, a plurality of split holes 251 may be provided at positions eccentric with respect to the optical axis A, and other configurations may be adopted for the number and arrangement of the split holes 251.

[0079] Further, the spectral splitting member 23, the first aperture 24, the second aperture 25, and the detection unit 33 may be configured to be rotatable while synchronizing around the optical axes A and B. In this case, for example, the reflecting surface of the optical scanner 51 can be configured to be arbitrarily tiltable in two axial directions (for example, directions around two axes perpendicular to each other with respect to the optical axis). Thereby, the scanning direction of the illumination light Ls with respect to the fundus Ef, which is the site to be observed, can be set in an arbitrary direction, or the direction of the slit-shaped illumination light Ls (for example, the direction of the long side direction of the illumination light Ls) can be changed. Therefore, the site to be observed can be observed with higher accuracy, for example, by applying the illumination light Ls from different angles to the illumination region R1. In addition to the spectral splitting member 23, the first aperture 24, the second aperture 25, and the detection unit 33, the optical scanner 51 may be rotated while synchronizing (for example, rotated around the normal line of the reflecting portion (reflecting surface) of the optical scanner 51) so that the scanning direction of the illumination light Ls with respect to the fundus Ef and the direction of the illumination light Ls change.

[0080] Further, as the spectral splitting member 23, for example, other optical members such as a pair of acousto-optic modulators (AOMs) that provide an angle of view, or a pair of electro-optic modulators (EOMs) may be used.

Description of Reference Numerals

[0081] 1 Ophthalmic device 2, 2A Illumination system 2-1, 2A-1 Plan view 2-2, 2A-2 Side view 3 Light-receiving system Side views of 5A1 to 5A3 Front views of 5B1 to 5B3 Side views of 6A1, 6A2 Front views of 6B1, 6B2 11 Apparatus main body 12 Operation unit 13 Display unit 14 Control device 21, 21A, 21B, 21C Light sources 22 First illumination system lens 23 Beam splitting member 23a Prism 23a1 Incident surface 23a2 Exit surface 24 First aperture 25 Second aperture 26 First illumination side optical system 27 Second illumination system lens 28 Third illumination system lens 29 Second illumination side optical system 31 Second focusing optical system 32 Light-receiving system lens 33 Detection unit 33a Light-receiving surface 51 Optical scanner 52 Optical path splitting member 53 Objective lens 141 Illumination control unit 142 Deflection control unit 143 Imaging control unit 144 Signal acquisition unit 145 Image generation unit 146 Focus confirmation control unit 147 Repetition control unit 148 Focus control unit 149 Display control unit 211 Near-infrared light source element 212 Visible light source element 213 Dichroic mirror 214 Red light source element 215 Green light source element 216 Blue light source element 217a First dichroic mirror 217b Second dichroic mirror 217c Third dichroic mirror 218 Dichroic Prism 241 Slit hole 251 split hole 521 Aperture A,B optical axis E. Examined eye Ea anterior segment Ef fundus LS illumination light Lb Return light Ls illumination light Ls11 First component light Ls12 First component light Ls21 Second component light Ls22 Second component light R1 lighting area S1~S3 Optical axis cross-sectional position

Claims

1. A light source, a spectroscopic member that spectroscopically disperses the light emitted from the light source, a first aperture having a slit aperture irradiated with each light emitted from the spectroscopic member, a second aperture having a plurality of divided apertures arranged in the spectroscopic direction of the spectroscopic member and dividing the light emitted from the slit aperture, an optical scanner that guides the light emitted from the second aperture to the observation site of the eye to be examined so that the illumination area can be moved, a light receiving system having a detection unit that detects the return light from the illumination area, a first focusing optical system that focuses the first aperture and the observation site, a second focusing optical system that is controlled so that the observation site and the detection unit are focused in conjunction with the focusing of the first focusing optical system, An ophthalmic apparatus comprising the above components.

2. The spectroscopic member deflects a part of the second direction perpendicular to the first direction, which is the spectroscopic direction, of the light emitted from the light source to one side of the first direction, and deflects the other part of the second direction to the other side of the first direction. The ophthalmic apparatus according to claim 1.

3. The spectroscopic member, a first prism arranged on a part side of the second direction so as to deflect a part of the second direction to one side of the first direction, a second prism arranged on the other part side of the second direction so as to deflect the other part of the second direction to the other side of the first direction, The ophthalmic apparatus according to claim 2, including the above components.

4. The ophthalmic apparatus according to any one of claims 1 to 3, wherein the conjugate position with respect to the first aperture is different from the conjugate position with respect to the second aperture.

5. The ophthalmic apparatus according to any one of claims 1 to 4, wherein the light source has a light source element capable of emitting near-infrared light and visible light.

6. An optical path splitting member that guides the light emitted from the optical scanner to the eye to be examined and guides the return light to the light receiving system is provided on the optical axis between the optical scanner and the eye to be examined. The ophthalmic apparatus according to any one of claims 1 to 5.

7. The spectroscopic member, the first aperture, the second aperture, the optical scanner, and the detection unit are configured to be rotatable while being synchronized around the optical axis. The ophthalmic apparatus according to any one of claims 1 to 6.

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