Ophthalmic device and ophthalmic optical system

Abstract

To provide an objective lens with good imaging performance by forming an intermediate pupil position in an objective optical system. [Solution] An ophthalmic device for observing a subject's eye, comprising a light source, a scanning unit (120, 142, 148) that scans light from the light source, and an objective optical system (130) that forms a pupil in the scanning unit that is conjugate with the pupil of the subject's eye (12), wherein the objective optical system comprises, in order from the scanning unit toward the subject's eye, a positive first lens group (134) and a positive second lens group (132), and a third lens group (133) that is disposed between the first lens group and the second lens group and includes a concave surface that diverges light.

Description

[Technical Field]

[0001] The present invention relates to an ophthalmic apparatus and an ophthalmic optical system. [Background technology]

[0002] European Patent Publication No. EP2901919A1 discloses an ophthalmologic apparatus having an attachment lens for capturing a wide-angle image of the fundus. Summary of the Invention

[0003] A first aspect of the technology disclosed herein is an ophthalmic device for observing a subject's eye, comprising a light source, a scanning unit that scans light from the light source, and an objective optical system that forms a pupil in the scanning unit that is conjugate with the pupil of the subject's eye, wherein the objective optical system comprises, in order from the scanning unit toward the subject's eye, a positive first lens group and a positive second lens group, and a third lens group that is disposed between the first lens group and the second lens group and includes a concave surface that diverges light.

[0004] A second aspect of the technology of the present disclosure is an ophthalmic optical system for observing a subject's eye, which includes an objective optical system that forms a pupil conjugate with the pupil of the subject's eye, and the objective optical system comprises, in order from the side where the pupil conjugate with the pupil of the subject's eye is formed toward the subject's eye, a positive first lens group and a positive second lens group, and the ophthalmic optical system has a third lens group that includes a concave surface that diverges light and is disposed between the first lens group and the second lens group. [Brief explanation of the drawings]

[0005] [Figure 1] 1 is a configuration diagram of an ophthalmologic apparatus according to a first embodiment. [Figure 2] 1 is a schematic diagram illustrating the configuration of a photographing optical system according to a first embodiment. [Figure 3] FIG. 2 is a diagram illustrating the configuration of an objective lens that constitutes a photographing optical system. [Figure 4] FIG. 2 is a diagram illustrating an example of a lens configuration of an objective lens according to Example 1. [Figure 5]4 is an aberration diagram showing lateral aberration of the objective lens according to Example 1. FIG. [Figure 6] FIG. 10 is a diagram illustrating an example of a lens configuration of an objective lens according to Example 2. [Figure 7] 10 is an aberration diagram showing lateral aberration of the objective lens according to Example 2. FIG. [Figure 8] FIG. 10 is a diagram illustrating an example of a lens configuration of an objective lens according to Example 3. [Figure 9] 10A and 10B are aberration diagrams showing lateral aberration of the objective lens according to Example 3. [Figure 10] FIG. 10 is a diagram illustrating an example of a lens configuration of an objective lens according to Example 4. [Figure 11] 10 is an aberration diagram showing the lateral aberration of the objective lens according to Example 4. FIG. [Figure 12] FIG. 10 is a schematic diagram showing a configuration in which an attachment optical system according to a second embodiment can be attached to and detached from a mobile terminal. [Figure 13] FIG. 10 is a schematic diagram showing an example of the configuration of an attachment optical system according to a second example. [Figure 14] FIG. 10 is a schematic diagram illustrating the configuration of an objective lens that constitutes an imaging optical system according to a third embodiment. [Figure 15] FIG. 10 is a diagram illustrating an example of a lens configuration of an objective lens according to Example 5. [Figure 16] FIG. 10 is a schematic diagram illustrating the configuration of an objective lens that constitutes an imaging optical system according to a fourth embodiment. [Figure 17] FIG. 10 is a schematic configuration diagram of an ophthalmologic apparatus according to a sixth embodiment. [Figure 18] FIG. 13 is a schematic diagram illustrating the configuration of an imaging optical system according to a first configuration example of the seventh embodiment. [Figure 19] FIG. 13 is a schematic diagram illustrating the configuration of an imaging optical system according to a second configuration example of the seventh embodiment. [Figure 20] FIG. 13 is a schematic diagram illustrating the configuration of an imaging optical system according to a third configuration example of the seventh embodiment. [Figure 21] FIG. 13 is a schematic diagram illustrating the configuration of an imaging optical system according to a fourth configuration example of the seventh embodiment. [Figure 22] FIG. 13 is a schematic diagram illustrating the configuration of an imaging optical system according to a fifth configuration example of the seventh embodiment. [Figure 23] FIG. 13 is a schematic diagram illustrating the configuration of an imaging optical system according to a sixth configuration example of the seventh embodiment. [Figure 24] FIG. 13 is a schematic diagram illustrating the configuration of an imaging optical system according to a seventh configuration example of the seventh embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0006] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0007] [First embodiment]

[0008] An ophthalmic apparatus 110 according to a first embodiment of the present disclosure will be described below with reference to the drawings. FIG. 1 shows a schematic configuration of an ophthalmic apparatus 110.

[0009] For ease of explanation, Scanning Laser Ophthalmoscope will be referred to as "SLO" and Optical Coherence Tomography will be referred to as "OCT."

[0010] When the ophthalmic apparatus 110 is placed on a horizontal plane, the horizontal direction is referred to as the "X direction," the vertical direction relative to the horizontal plane is referred to as the "Y direction," and the direction of the optical axis of the imaging optical system 116A is referred to as the "Z direction." The apparatus is positioned relative to the eye to be examined so that the center of the pupil of the eye to be examined is located on the optical axis in the Z direction. The X direction, Y direction, and Z direction are perpendicular to each other.

[0011] The ophthalmologic apparatus 110 includes an imaging device 14 and a control device 16. The imaging device 14 includes an SLO unit 18 that acquires an image of the fundus of the subject's eye 12 and an OCT unit 20 that acquires a tomographic image of the subject's eye 12. Hereinafter, a fundus image generated based on SLO data acquired by the SLO unit 18 will be referred to as an SLO image. Also, a tomographic image generated based on OCT data acquired by the OCT unit 20 will be referred to as an OCT image. Note that an SLO image may also be referred to as a two-dimensional fundus image. Also, an OCT image may also be referred to as a fundus tomographic image or an anterior segment tomographic image depending on the imaging region of the subject's eye 12. The ophthalmic apparatus 110 is an example of the "ophthalmic apparatus" of the technology of the present disclosure.

[0012] The control device 16 comprises a computer having a CPU (Central Processing Unit) 16A, a RAM (Random Access Memory) 16B, a ROM (Read-Only Memory) 16C, and an input / output port (I / O) 16D.

[0013] The control device 16 includes an input / display device 16E connected to the CPU 16A via an I / O port 16D. The input / display device 16E has a graphic user interface that displays an image of the subject's eye 12 and receives various instructions from the user. A touch panel display may be used as the input / display device 16E. The control device 16 also includes a communication I / F 16F connected to the I / O port 16D.

[0014] The control device 16 also includes an image processing device 17 connected to the I / O port 16 D. The image processing device 17 generates an image of the subject's eye 12 based on the data obtained by the photographing device 14.

[0015] 1, the control device 16 of the ophthalmic apparatus 110 includes the input / display device 16E, but the technology of the present disclosure is not limited to this. For example, the control device 16 of the ophthalmic apparatus 110 may not include the input / display device 16E, but may include an input / display device that is physically independent from the ophthalmic apparatus 110. In this case, the display device includes an image processing processor unit that operates under the control of the CPU 16A of the control device 16. The image processing processor unit may display an SLO image or the like based on an image signal instructed to be output by the CPU 16A.

[0016] The photographing device 14 operates under the control of the control device 16. The photographing device 14 includes an SLO unit 18, a photographing optical system 116A, and an OCT unit 20. The photographing optical system 116A is moved in the X, Y, and Z directions by a photographing optical system driving unit (not shown) under the control of the CPU 16A. Alignment (positioning) between the photographing device 14 and the subject's eye 12 may be performed, for example, by moving not only the photographing device 14 but also the entire ophthalmic apparatus 110 in the X, Y, and Z directions.

[0017] The SLO system is realized by the control device 16, the SLO unit 18, and the imaging optical system 116A shown in FIG.

[0018] The SLO unit 18 includes multiple light sources. For example, as shown in FIG. 1 , the SLO unit 18 includes a light source 40 for B light (blue light), a light source 42 for G light (green light), a light source 44 for R light (red light), and a light source 46 for IR light (infrared light, e.g., near-infrared light). The light emitted from each of the light sources 40, 42, 44, and 46 is directed to the same optical path via optical elements 48, 50, 52, 54, and 56. The optical elements 48 and 56 are mirrors, and the optical elements 50, 52, and 54 are beam splitters. The B light is guided to the optical path of the imaging optical system 116A via the optical elements 48, 50, and 54. The G light is guided to the optical path of the imaging optical system 116A via the optical elements 50 and 54. The R light is guided to the optical path of the imaging optical system 116A via the optical elements 52 and 54. The IR light is guided to the optical path of the imaging optical system 116A via optical members 56 and 52. The light sources 40, 42, 44, and 46 can be LED light sources or laser light sources. An example using a laser light source will be described below. The optical members 48 and 56 can be total reflection mirrors. The optical members 50, 52, and 54 can be dichroic mirrors, half mirrors, etc. The light sources 40, 42, 44, and 46 are examples of the "light source" of the technology of the present disclosure.

[0019] The SLO unit 18 is configured to be switchable between various light emission modes, such as a light emission mode in which G light, R light, B light, and IR light are individually emitted, and a light emission mode in which all or some of these light sources are simultaneously emitted. In the example shown in FIG. 1 , four light sources are provided: a B light (blue light) light source 40, a G light source 42, an R light source 44, and an IR light source 46; however, the technology of the present disclosure is not limited to this. For example, the SLO unit 18 may further include a white light source. In this case, in addition to the various light emission modes described above, a light emission mode in which only white light is emitted may be set.

[0020] The laser light incident on the photographing optical system 116A from the SLO unit 18 is scanned in the X and Y directions by scanning units (120, 142) described below. The scanning light passes through the pupil 27 and is irradiated onto the posterior segment (e.g., the fundus) of the subject's eye 12. The light reflected by the fundus is incident on the SLO unit 18 via the photographing optical system 116A. The scanning units (120, 142) are an example of the "scanning unit" of the technology of the present disclosure.

[0021] The light reflected by the fundus of the subject's eye 12 is detected by light detection elements 70, 72, 74, and 76 provided in the SLO unit 18. In this embodiment, the SLO unit 18 includes a B light detection element 70, a G light detection element 72, an R light detection element 74, and an IR light detection element 76 corresponding to the multiple light sources, namely, the B light source 40, the G light source 42, the R light source 44, and the IR light source 46. The B light detection element 70 detects the B light reflected by the beam splitter 64. The G light detection element 72 detects the G light that passes through the beam splitter 64 and is reflected by the beam splitter 58. The R light detection element 74 detects the R light that passes through the beam splitters 64 and 58 and is reflected by the beam splitter 60. The IR light detection element 76 detects the G light that passes through the beam splitters 64, 58, and 60 and is reflected by the beam splitter 62. The photodetecting elements 70, 72, 74, and 76 may be, for example, avalanche photodiodes (APDs). ode: avalanche photodiode).

[0022] Under the control of the CPU 16A, the image processing device 17 generates SLO images corresponding to each color using signals detected by the B light detection element 70, the G light detection element 72, the R light detection element 74, and the IR light detection element 76. The SLO images corresponding to each color include a B-SLO image generated using the signal detected by the B light detection element 70, a G-SLO image generated using the signal detected by the G light detection element 72, an R-SLO image generated using the signal detected by the R light detection element 74, and an IR-SLO image generated using the signal detected by the IR light detection element 76. In a light emission mode in which the B light source 40, the G light source 42, and the R light source 44 emit light simultaneously, an RGB-SLO image may be synthesized from the B-SLO image, the G-SLO image, and the R-SLO image generated using the signals detected by the R light detection element 74, the G light detection element 72, and the B light detection element 70, respectively. Furthermore, in a light emission mode in which the G light source 42 and the R light source 44 emit light simultaneously, an RG-SLO image may be synthesized from a G-SLO image and an R-SLO image generated using the signals detected by the R light detection element 74 and the G light detection element 72. In the first embodiment, an RG-SLO image is used as the SLO image, but this is not limiting, and other SLO images may be used. The beam splitters 58, 60, 62, and 64 may be dichroic mirrors, half mirrors, or the like.

[0023] The OCT system is a three-dimensional image acquisition device realized by the control device 16, OCT unit 20, and imaging optical system 116A shown in Fig. 1. The OCT unit 20 includes a light source 20A, a sensor (detection element) 20B, a first optical coupler 20C, a reference optical system 20D, a collimating lens 20E, and a second optical coupler 20F.

[0024] The light source 20A generates light for optical coherence tomography. For example, a super luminescent diode (SLD) can be used as the light source 20A. The light source 20A generates low-coherence broadband light with a wide spectral bandwidth. The light emitted from the light source 20A is split by the first optical coupler 20C. One of the split beams is collimated by a collimating lens 20E as measurement light and then enters the imaging optical system 116A. The measurement light is scanned in the X and Y directions by scanning units (148, 142), which will be described later. The scanned light is irradiated onto the anterior segment of the subject's eye or the posterior segment via the pupil 27. The measurement light reflected from the anterior or posterior segment enters the OCT unit 20 via the imaging optical system 116A, and then enters the second optical coupler 20F via the collimating lens 20E and the first optical coupler 20C. In this embodiment, SD-OCT using an SLD as the light source 20A is exemplified, but the present invention is not limited to this, and SS-OCT using a wavelength swept light source instead of an SLD may also be adopted.

[0025] The other light beam emitted from the light source 20A and branched by the first optical coupler 20C is incident as reference light on the reference optical system 20D, passes through the reference optical system 20D, and then enters the second optical coupler 20F.

[0026] The measurement light (return light) reflected and scattered by the subject's eye 12 and the reference light are combined by the second optical coupler 20F to generate interference light. The interference light is detected by the sensor 20B. The image processing device 17 generates a tomographic image of the subject's eye 12 based on the detection signal (OCT data) from the sensor 20B.

[0027] In the first embodiment, the OCT system generates a tomographic image of the anterior or posterior segment of the subject's eye 12.

[0028] The anterior part of the subject's eye 12 includes, as an anterior segment, for example, the cornea, the iris, the angle of the eye, the crystalline lens, The posterior segment of the subject's eye 12 is a portion including the ciliary body, the vitreous body, and a portion of the vitreous body. The posterior segment of the subject's eye 12 is a portion including, as a posterior segment, for example, the remaining portion of the vitreous body, the retina, the choroid, and the sclera. The vitreous body belonging to the anterior segment is the portion of the vitreous body on the cornea side, with the XY plane passing through the point of the crystalline lens closest to the center of the eye as its boundary, and the vitreous body belonging to the posterior segment is the portion of the vitreous body other than the vitreous body belonging to the anterior segment.

[0029] When the anterior segment of the subject's eye 12 is the imaging target region, the OCT system generates, for example, a tomographic image of the cornea. When the posterior segment of the subject's eye 12 is the imaging target region, the OCT system generates, for example, a tomographic image of the retina.

[0030] 2 shows a schematic configuration of the imaging optical system 116A. The imaging optical system 116A includes, arranged in this order from the subject's eye 12 side, an objective lens 130, a horizontal scanning unit 142, a relay lens device 140, a beam splitter 147, vertical scanning units 120 and 148, a focus adjustment device 150, and a collimating lens 20E. As the beam splitters 178 and 147, for example, a dichroic mirror, a half mirror, or the like can be used.

[0031] The horizontal scanning unit 142 is an optical scanner that horizontally scans the SLO laser light and OCT measurement light incident via the relay lens device 140. In this embodiment, the horizontal scanning unit 142 is shared by the SLO optical system and the OCT optical system, but this is not limited thereto. A horizontal scanning unit may be provided for each of the SLO optical system and the OCT optical system.

[0032] The collimating lens 20E converts the measurement light emitted from the end 158 of the fiber through which the light emitted from the OCT unit 20 travels into parallel light.

[0033] The focus adjustment device 150 includes a plurality of lenses 152, 154. The focus position of the measurement light on the subject's eye 12 is adjusted by appropriately moving each of the plurality of lenses 152, 154 in the optical axis direction according to the imaging region of the subject's eye 12. Although not shown, if a focus detection device is provided, the focus adjustment device can drive the lenses 152, 154 according to the focus detection state to automatically adjust the focus, thereby realizing an autofocus device.

[0034] The vertical scanning unit 148 is an optical scanner that scans the measurement light incident via the focus adjustment device 150 in the vertical direction.

[0035] The vertical scanning unit 120 is an optical scanner that scans the laser light incident from the SLO unit 18 in the vertical direction.

[0036] Relay lens device 140 includes multiple lenses 144, 146 each having positive power. Relay lens device 140 is configured by multiple lenses 144, 146 so that the positions of vertical scanning units 148, 120 and horizontal scanning unit 142 are conjugate with each other. More specifically, relay lens device 140 is configured so that the central positions of the angular scans of both scanning units are conjugate with each other.

[0037] The beam splitter 147 is disposed between the relay lens device 140 and the vertical scanning unit 148. The beam splitter 147 is an optical element that combines the SLO optical system and the OCT optical system, and reflects the SLO light emitted from the SLO unit 18 toward the relay lens device 140, and transmits the measurement light emitted from the OCT unit 20 toward the relay lens device 140. The measurement light emitted from the OCT unit 20 is two-dimensionally scanned by the vertical scanning unit 148 and the horizontal scanning unit 142. The emitted light is two-dimensionally scanned by the vertical scanning unit 120 and horizontal scanning unit 142 that constitute the SLO optical system. The two-dimensionally scanned OCT measurement light and SLO laser light are each incident on the subject's eye 12 via the objective lens 130 that constitutes a common optical system. The SLO laser light reflected by the subject's eye 12 is incident on the SLO unit 18 via the objective lens 130, horizontal scanning unit 142, relay lens device 140, beam splitter 147, and vertical scanning unit 120. The OCT measurement light that has passed through the subject's eye 12 is incident on the OCT unit 20 via the objective lens 130, horizontal scanning unit 142, relay lens device 140, beam splitter 147, vertical scanning unit 148, focus adjustment device 150, and collimator lens 20E.

[0038] For example, a resonant scanner, a galvanometer mirror, a polygon mirror, a rotating mirror, a dowel prism, a double dowel prism, a rotation prism, a MEMS mirror scanner, an acousto-optical element (AOM), or the like is suitably used as the horizontal scanning unit 142 and the vertical scanning units 120 and 148. In this embodiment, a galvanometer mirror is used as the vertical scanning unit 148, and a polygon mirror is used as the vertical scanning unit 120. Note that if a two-dimensional optical scanner such as a MEMS mirror scanner is used instead of an optical scanner such as a polygon mirror or a galvanometer mirror, the incident light can be two-dimensionally angle-scanned by the reflective element, and therefore the relay lens device 140 may be eliminated.

[0039] The objective lens 130 includes, in order from the horizontal scanning unit 142 side, a first lens group 134 and a second lens group 132, and at least the second lens group 132 is a positive lens group having a positive power as a whole. In the first embodiment, the first lens group 134 is also a positive lens group having a positive power as a whole. The first lens group 134 and the second lens group 132 each include at least one positive lens. When the first lens group 134 and the second lens group 132 each include a plurality of lenses, the first lens group 134 and the second lens group 132 may each include a negative lens as long as they have a positive power as a whole.

[0040] The objective lens 130 of the present disclosure also includes a third lens group 133 in the space between the first lens group 134 and the second lens group 132.

[0041] The first lens group 134 is an example of the "first lens group" of the technology of the present disclosure, the second lens group 132 is an example of the "second lens group" of the technology of the present disclosure, and the third lens group 133 is an example of the "third lens group" of the technology of the present disclosure.

[0042] The first lens group 134 and the second lens group 132 that constitute the objective lens 130 are separated by the longest air gap on the optical axis AX between the lens surfaces of the objective lens 130. The third lens group 133 is disposed in the space with the longest air gap.

[0043] As a result, the distance between the first lens group 134 and the third lens group 133 and the air distance between the third lens group 133 and the second lens group 132 are the largest and second largest air distances among the lens distances of the entire objective lens 130. When the third lens group 133, which serves as an intermediate group, is disposed between the first lens group 134 and the second lens group 132 and closer to the eye 12, the distance between the first lens group 134 and the third lens group 133 is maximized, and when the third lens group 133 is disposed in the scanning unit, the distance between the third lens group 133 and the second lens group 132 is maximized. Note that even if a glass plate having no power is located between the first lens group 134 and the second lens group 132, the glass plate is not considered to be a lens belonging to either the first lens group 134 or the second lens group 132, and the first lens group 134 and the second lens group 132 are considered to be separated by the longest air distance. This longest air gap is suitable for providing a combining section having light combining and light separating functions, such as a dichroic mirror.

[0044] Although not shown, the imaging optical system 116A may include an optical module including a fixation lamp for presenting a fixation target, a camera, and an illumination device. Such an optical module may be arranged so as to be combined with the optical path of the imaging optical system 116A by a beam splitter or the like.

[0045] The photographing optical system 116A includes an objective lens 130 that functions as a posterior-segment observation optical system for observing at least the posterior segment of the eye 12, including the fundus. The photographing optical system 116A includes an optical module for anterior-segment observation (not shown) that is insertable into and detachable from the optical path of the objective lens 130, and by disposing the optical module for anterior-segment observation in the optical path of the objective lens 130, it is possible to switch from the posterior-segment observation optical system to the anterior-segment observation optical system. In the first embodiment, the photographing optical system 116A will be described mainly with reference to the posterior-segment observation optical system, and a description of the photographing optical system 116A that functions as an anterior-segment observation optical system in which an optical module for anterior-segment observation is disposed in the optical path of the objective lens 130 will be omitted.

[0046] FIG. 3 shows an example of a specific configuration of the objective lens 130 constituting the imaging optical system 116A that functions as a posterior segment observation optical system for observing the posterior segment of the subject's eye 12. In FIG.

[0047] The scanning center positions of the horizontal scanning unit 142 and the vertical scanning unit 148 shown in FIG. 2 correspond to the scanning center position Ps shown in FIG. 3. The objective lens 130 is disposed so that the scanning center position Ps is conjugate with the pupil position (pupil position) P2 of the subject's eye 12. That is, the scanning center position Ps by the scanning unit is configured to coincide with a pupil position conjugate to the pupil position P2 of the subject's eye 12 (hereinafter referred to as the pupil conjugate position P1). In the SLO optical system, the SLO laser light scanned by the vertical scanning unit 120 and the horizontal scanning unit 142 passes through the objective lens 130 and is angularly scanned two-dimensionally around the pupil position P2 of the subject's eye 12. As a result, the focal point of the SLO laser light is scanned two-dimensionally on the fundus of the subject's eye 12. Similarly, in the OCT optical system, the measurement light scanned by the vertical scanning unit 148 and the horizontal scanning unit 142 passes through the objective lens 130 and is angularly scanned two-dimensionally around the pupil position P2 of the subject's eye 12. As a result, the focal point of the measurement light is two-dimensionally scanned on the fundus of the subject's eye 12. When observing the posterior segment of the eye, the SLO unit 18 acquires a two-dimensional fundus image, and the OCT unit 20 acquires a tomographic image of the fundus.

[0048] An important point in such a configuration is that the light supplied to each scanning unit of the SLO or OCT is a parallel beam, and the parallel beam is angularly scanned at the pupil P2 of the subject's eye by the angular scanning performed by the scanning unit. For this reason, the objective lens 130 as a whole must constitute an afocal system. The scanning angle of the parallel beam at the pupil P2 of the subject's eye is determined by the scanning angle of the scanning unit and the angular magnification of the objective lens 130. For this reason, the paraxial angular magnification M of the objective lens 130 is preferably approximately 1.5 to 5 times (1.5≦M≦5).

[0049] An intermediate pupil position P3 is formed in the third lens group 133 (G3) as an intermediate group. The light rays shown in Fig. 3 indicate the chief rays of the scanning light beams at five angles up to the maximum angle that are incident on the pupil P2 of the subject's eye 12, and it is clear that these chief rays intersect within the third lens group 133 (G3).

[0050] Specifically, the objective lens 130 functions as an optical system that transfers the scanning center position Ps of the scanning unit to the pupil (pupil position P2) of the subject's eye 12, and is equipped with a plurality of lens groups including a positive first lens group 134 (G1) and a positive second lens group 132 (G2). The objective lens 130 is configured so that a position (hereinafter referred to as intermediate pupil position P3) that is conjugate with the scanning center position Ps of the scanning unit is formed between the first lens group 134 and the second lens group 132. In other words, the scanning center position Ps is the pupil conjugate position P1, and the pupil position P2 and the intermediate pupil position P3 of the subject's eye 12 are conjugate with each other. 3, the first lens group 134 (G1) includes, in order from the pupil conjugate position P1 side, which is on the scanning unit side (e.g., the side of the nearest horizontal scanning unit 142), to the subject's eye 12 side, a positive meniscus lens L11 with a convex surface facing the scanning unit side, a negative lens L12 with a concave surface facing the scanning unit side, a positive meniscus lens L13 with a concave surface facing the scanning unit side, and a positive lens component (a cemented lens of a negative lens L14 and a positive lens L15) on the scanning unit side. In this specification, the term "lens component" refers to a lens with two surfaces that contact air on the optical axis, and one lens component refers to one single lens or a set of cemented lenses formed by cementing together multiple lenses. The lens components of the first lens group 134 are effective for correcting chromatic aberration when they are cemented lenses as shown in the figure, but can be single lenses when the wavelength range of the light used is relatively narrow.

[0051] The second lens group 132 (G2) includes, in order from the scanning unit side to the eye to be examined, a positive lens L21, a positive meniscus lens component with its convex surface facing the scanning unit side (a cemented lens of a positive lens L22 and a negative lens L23), and a positive meniscus lens L24 with its convex surface facing the scanning unit side. The meniscus lens component of the second lens group 132 is effective for correcting chromatic aberration when it is a cemented lens as shown in the figure, but can be a single lens when the wavelength range of the light used is relatively narrow.

[0052] The third lens group 133 (G3) includes, in order from the scanning unit side to the eye to be examined, a positive or negative lens component on the scanning unit side (for example, a cemented lens of a positive lens L31 and a negative lens L32), a meniscus lens L33 with a convex surface facing the scanning unit side, and a meniscus lens L34 with a concave surface facing the scanning unit side. The third lens group 133 is formed to include an intermediate pupil position P3. It is preferable to form the pupil conjugate point P3 between the negative meniscus lens L33 with a convex surface facing the scanning unit side and the meniscus negative lens L34 with a concave surface facing the scanning unit side, i.e., at a position sandwiched between the concave surfaces of both lenses. It should be noted that the first lens group 134 (G1) and the second lens group 132 (G2) both have positive refractive power, but the third lens group 133 (G3) serving as the intermediate group only needs to have a strongly diverging surface in the vicinity of the intermediate pupil position P3, which is extremely effective in terms of aberration correction, and it is preferable that the refractive power of the third lens group 133 (G3) is primarily positive, but it can also be negative.

[0053] Here, the imaging optical system 116A forms a wide-angle optical system, thereby enabling observation of the fundus of the subject's eye 12 over a wide field of view (FOV). The field of view (FOV) indicates the range that can be captured by the imaging device 14. The field of view (FOV) can be expressed as a field of view angle. In the first embodiment, the field of view angle can be defined by an internal illumination angle and an external illumination angle. The external illumination angle is the illumination angle of the light beam irradiated from the ophthalmic device 110 to the subject's eye 12, defined with the pupil 27 as the reference. The internal illumination angle is the illumination angle of the light beam irradiated to the fundus of the subject's eye 12, defined with the eyeball center O as the reference. The external illumination angle and the internal illumination angle correspond to each other. For example, if the external illumination angle is 120 degrees, the internal illumination angle corresponds to approximately 160 degrees.

[0054] When forming an objective lens 130 with a large wide angle (for example, an ultra-wide field (UWF) angle of more than 100 degrees) to observe the subject's eye 12 with a wide field of view (FOV), it is important to correct aberrations of the objective lens 130, and curvature of the image plane, for example, Petzval sum, tends to increase. Therefore, in the first embodiment, an optical system is provided that can suppress curvature of the image plane, for example, Petzval sum, with the ultra-wide angle objective lens 130.

[0055] Specifically, in the first embodiment, as an example of an ophthalmic optical system of the present disclosure, an objective lens 130 includes a first lens group 134 and a second lens group 132, each of which has a positive power, and a third lens group 133 including a concave surface that diverges light is disposed between the first lens group 134 and the second lens group 132. That is, a concave surface, which is a surface (diverging surface) in the direction in which light diverges from the glass material into space, may be included between the positive first lens group 134 and the positive second lens group 132. In other words, the objective lens 130 includes, in order from the scanning unit side toward the subject's eye 12, the positive first lens group 134 and the positive second lens group 132, and a third lens group 133 including a concave surface that diverges light is disposed between the first lens group 134 and the second lens group 132.

[0056] By forming the objective lens 130 in this manner, it is possible to at least suppress an increase in the Petzval sum of the objective lens 130.

[0057] Incidentally, when forming an objective lens 130 with a large wide angle (for example, an ultra-wide angle (UWF) exceeding 100 degrees) in order to observe the subject's eye 12 with a wide field of view FOV, the lens diameter increases as the field angle increases. Furthermore, as the lens diameter increases, the total amount of lens glass material increases, and the total weight of the objective lens also increases. Furthermore, when forming the objective lens 130, aberration correction of the objective lens 130 is important, and the action of the lens system on the pupil targeted by the objective lens 130 greatly affects the aberration correction of the objective lens 130. Therefore, in the first embodiment, an optical system that makes it possible to reduce the maximum aperture of the objective lens 130 is provided. Specifically, in the first embodiment, as an example of an ophthalmic optical system according to the present disclosure, an intermediate pupil is formed within the objective lens 130, thereby reducing the maximum aperture of the objective lens 130.

[0058] In the first embodiment, the objective lens 130 forms an intermediate pupil between the first lens group 134 and the second lens group 132, which is different from the pupil conjugate with the pupil of the test eye 12, and the third lens group 133 is positioned to include the position of the intermediate pupil.

[0059] By configuring the objective lens 130 to form an intermediate pupil in this manner, it is possible to improve the imaging performance of the objective lens while at least suppressing an increase in the lens diameter of the objective lens 130, thereby suppressing the total weight of the objective lens 130 due to the increase in lens diameter. That is, by positioning the third lens group 133 in the objective lens 130 so that it includes the intermediate pupil position P3, it is possible to improve the aberration correction function provided by the concave surface of the third lens group 133. Furthermore, by positioning the concave surface closer to the intermediate pupil position, the divergence effect of the concave surface can be strengthened compared to when the concave surface is located farther away from the pupil, making it easier to correct the Petzval sum. Therefore, various aberrations occurring in the second lens group, which is closest to the subject's eye and tends to have a large diameter, can be easily corrected by combining the first lens group 134 and the third lens group 133. This allows the UWF objective lens to achieve excellent performance despite its overall compact size.

[0060] Incidentally, in the configuration of the objective lens 130, it is preferable to increase the distance between the scanning unit and the conjugate position Ps of the pupil of the subject's eye, where the scanning unit is provided, and the distance between the scanning unit and the pupil position P2 of the subject's eye (so-called working distance). On the other hand, as long as the third lens group 133 is positioned between the first lens group 134 and the second lens group 132 and is positioned so as to include the intermediate pupil position P3, there are few restrictions on its position and the aberration correction capability is high. Therefore, as illustrated in Figure 3, the objective lens 130 configured to form an intermediate pupil is preferably configured to satisfy the following conditional expression (1), where W1 is the distance between the lens surface farthest from the subject's eye 12 included in the first lens group 134 and the position of the scanning unit (pupil conjugate position P1, which is the scanning center position Ps), W2 is the distance between the lens surface closest to the subject's eye 12 included in the second lens group 132 and the pupil position P2 of the subject's eye (hereinafter referred to as the working distance on the subject's eye 12 side), and D is the distance between the concave surface with the strongest divergence power included in the third lens group 133 and the intermediate pupil position P3. D <W1、 D<W2 ···(1)

[0061] That is, an intermediate pupil position P3, which is a pupil conjugate position different from the pupil conjugate position P1, is formed between the pupil conjugate position P1 where the scanning unit is arranged and the pupil P2 of the eye to be examined, and the intermediate pupil position P3 and the intermediate pupil position The distance D to the concave surface S3 closest to P3 is set smaller than the smaller value of the working distance W1 on the scanning unit side and the working distance W2 on the eye 12 side. With this configuration, the imaging performance of the objective lens 130 can be further improved.

[0062] When considering the aberration of the objective lens 130, it is preferable to optimize the Petzval image plane, which is influenced by the Petzval curvature of the lens surface. Therefore, as illustrated in FIG. 3, it is preferable that the objective lens 130 be configured to satisfy the following conditional expression (2), where C1 is the Petzval curvature of the concave surface (divergence surface) S1 in the first lens group 134 that is closest to the scanning unit, C2 is the Petzval curvature of the concave surface (divergence surface) S2 in the second lens group 132 that is closest to the eye to be examined, and C3 is the Petzval curvature of the concave lens surface S3 of the third lens group 133 that has divergence power. C3 <C1、C3<C2 ···(2)

[0063] Here, the Petzval curvature C is calculated by the following formula (3) where R is the radius of curvature of the surface, N is the refractive index on the incident side of the surface, and N' is the refractive index on the exit side of the surface. C={(1 / N')-(1 / N)} / (-R) ···(3)

[0064] That is, the Petzval curvature C3 of the concave surface S3 having the strongest divergence power among the concave surfaces of the lenses included in the third lens group 133 is made even more negative than either the Petzval curvature C1 of the concave surface S1 of the lens included in the first lens group 134 having the divergence power closest to the scanning unit or the Petzval curvature C2 of the concave surface S2 of the lens included in the second lens group 132 having the divergence power closest to the subject's eye 12, whichever is more negative.

[0065] This configuration can further improve the imaging performance of the objective lens 130. That is, by providing the objective lens 130 with the third lens group 133 having a pupil conjugate image, a strong diverging surface S3 can be provided near the pupil conjugate point of this third lens group 133. Furthermore, by configuring the Petzval curvature C3 as described above, the Petzval sum of the entire objective optical system including the objective lens 130 can be made smaller than that of an objective lens not having the third lens group 133 having a pupil conjugate image, and extremely excellent imaging performance can be achieved.

[0066] When considering the maximum aperture of the objective lens 130, the lenses included in the second lens group 132 on the test eye side have a large effect. On the other hand, when the objective lens 130 is formed so that an intermediate pupil is built in by the third lens group 133, if the aperture of the lenses included in the third lens group 133 is larger than that of the second lens group 132, the bottleneck that limits the maximum aperture of the objective lens 130 becomes the aperture of the lenses included in the third lens group 133, which becomes an obstacle when trying to limit the maximum aperture of the objective lens 130. Therefore, it is preferable that the objective lens 130 be configured to satisfy the following conditional expression (4), where the maximum effective diameter of the lenses included in the first lens group 134 is φ1, the maximum effective diameter of the lenses included in the second lens group 132 is φ2, and the maximum effective diameter of the lenses included in the third lens group 133 is φ3. φ3, φ1<0.7·φ2 (4)

[0067] That is, the maximum effective diameter φ1 of the lenses included in the first lens group 134 and the maximum effective diameter φ3 of the lenses included in the third lens group 133 are both smaller than 70% of the maximum effective diameter φ2 of the lenses included in the second lens group 132.

[0068] By configuring it in this way, it is possible to make the objective lens 130 smaller and lighter.

[0069] According to the first embodiment described above, by configuring the objective lens 130 to satisfy the above-described conditions, the scanning center position Ps (pupil conjugate position P1) of the scanning unit is transferred to the pupil (pupil position P2) of the subject's eye by the objective lens 130. Furthermore, in the objective lens 130, a pupil conjugate point Po (intermediate pupil position P3) is formed in the third lens group 133, and the conjugate point Po (intermediate pupil position P3) is also conjugate with the scanning center position Ps (pupil conjugate position P1). The concave surface (i.e., diverging surface) at this conjugate point Po (intermediate pupil position P3) is extremely effective for correcting aberrations of the entire objective lens 130 (effective for correcting Petzval sum), thereby significantly improving the imaging performance of the objective lens 130. Furthermore, the apertures of the first lens group 134 and the second lens group 132 can be reduced, enabling the entire objective lens 130 to be made smaller and lighter despite being an ultra-wide-angle (UWF) lens.

[0070] In the first embodiment, the case where light is scanned by the horizontal scanning unit 142 and the vertical scanning unit 148 has been described, but examples of the horizontal scanning unit 142 and the vertical scanning unit 148 include, but are not limited to, a polygon mirror or a galvanometer mirror. For example, other optical elements capable of scanning the scanning light in the Y direction may be used, and examples include a MEMS (Micro-electromechanical system) mirror, a rotating mirror, a prism, or a resonant mirror.

[0071] Furthermore, it goes without saying that the same scanning can be performed by switching the X direction and the Y direction in the scanning light in the first embodiment.

[0072] Preferred Embodiments Next, an example of the objective lens 130 of the technique of the present disclosure will be described.

[0073] Example 1 4 shows an example of the lens configuration of the objective lens 130 according to Example 1. The objective lens 130 is a dioptric system including lenses L11 to L34. FIG. 4 shows the pupil conjugate position P1, which is common to the scanning center position Ps of the scanning unit, the pupil position (pupil position) P2 of the subject's eye 12, and the intermediate pupil position P3, which is the pupil conjugate point Po. Note that P1, P2, and P3 in the figure are shown to indicate positions in the optical axis direction, and do not represent shapes or sizes. The objective lens 130 includes, in order from the scanning unit side, a first lens group 134 (G1) and a second lens group 132 (G2). The third lens group 133 (G3) is disposed between the first lens group 134 (G1) and the second lens group 132 (G2). As described above, the intermediate pupil position P3 is formed within the third lens group 133 (G3) as an intermediate group. The light rays shown in FIG. 4 represent the chief ray of the scanning light beam incident at the maximum angle on the pupil P2 of the subject's eye, as is clear from the fact that this light ray intersects within the third lens group 133 (G3).

[0074] In the following description, the first lens group 134 may be referred to as the first lens group G1, the second lens group 132 may be referred to as the second lens group G2, and the third lens group 133 may be referred to as the third lens group G3. In the example shown in Fig. 4, the third lens group G3 is disposed in a space separated by an air gap between the first lens group G1 and the second lens group G2, and the air gap between the third lens group G3 and the second lens group G2 is the longest within the objective lens 130.

[0075] The first lens group G1 includes, in order from the pupil conjugate position P1 side (scanning unit side) to the subject's eye 12 side, a positive meniscus lens L11 with a concave surface facing the scanning unit side, a negative lens L12 with a concave surface facing the scanning unit side, a positive lens L13, a positive lens L14, and a negative lens L15. The lenses L12 and L13 are cemented together to form a lens component in the shape of a meniscus lens with a concave surface facing the scanning unit side. The lenses L14 and L15 are cemented together to form a lens component in the shape of a meniscus lens with a concave surface facing the scanning unit side. The lens component is a meniscus lens with a convex surface facing the lens side.

[0076] The second lens group G2 includes, in order from the scanning unit side to the examined eye side, a positive lens L21, a positive lens L22, a negative lens L23, and a positive meniscus lens L24 with its convex surface facing the scanning unit side. The lenses L22 and L23 are cemented together to form a meniscus lens component with its concave surface facing the examined eye 12 side.

[0077] The third lens group G3 includes, in order from the scanning unit side to the examined eye side, a positive lens L31, a negative lens L32, a meniscus lens L33 with a convex surface facing the scanning unit side, and a meniscus lens L34 with a concave surface facing the scanning unit side. The lenses L31 and L32 are cemented together to form a meniscus lens component. Here, the concave lens surface S3 of the third lens group G3, which has the strongest divergence power, is the concave surface of the negative lens L33 facing the examined eye side.

[0078] Table 1 shows the lens data for Example 1. The lens data lists, from left to right, the surface number (No.), radius of curvature, surface spacing on the optical axis, refractive index (Nd) based on the d-line (wavelength 587.56 nm), and Abbe number (vd) based on the d-line. The first surface in the lens data is the pupil-conjugate position P1, which is shared with the scanning center position Ps of the scanning unit. In the table, this is represented as an "aperture" on a virtual plane (with a radius of curvature indicated as inf). The value in the last row of the surface spacing column indicates the distance on the optical axis from the lens surface closest to the subject's eye to the pupil position (pupil position) P2. Note that because the objective lens 130 is an afocal system, the table is written assuming that the object is positioned at infinity. Surfaces 7, 11, 15, and 20 are virtual planes used to evaluate the performance of the objective lens 130 and do not affect the light passing through them. [Table 1]

[0079] Figure 5 shows the lateral aberration of the objective lens configured with the specifications in Table 1. In the lateral aberration diagram shown in Figure 5, the vertical axis represents the image height, the solid line represents the central wavelength of 850.0 nm, the dashed line represents 633.0 nm, the one-dot chain line represents 532.0 nm, and the two-dot chain line represents 486.1327 nm. As is clear from the lateral aberration diagram shown in Figure 5, it is confirmed that the objective lens 130 of Example 1 suppresses variations in aberrations for light in a wide wavelength range, including light in the visible wavelength range and light in the near-infrared range, and that the aberrations are well corrected.

[0080] Example 2 6 shows an example of the lens configuration of the objective lens 130 according to Example 2. Since Example 2 has the same configuration as Example 1, the same parts are given the same reference numerals and detailed description thereof will be omitted.

[0081] The first lens group G1 includes, in order from the pupil conjugate position P1 side (scanning unit side) to the eye to be examined, a positive meniscus lens L11 with a convex surface facing the scanning unit side, a negative lens L12 with a concave surface facing the eye to be examined 12 side, a positive meniscus lens L13 with a concave surface facing the scanning unit side, a positive meniscus lens L14 with a convex surface facing the scanning unit side, and a positive lens L15. Lenses L14 and L15 are cemented together to form a biconvex lens component.

[0082] The second lens group G2 includes, in order from the scanning unit side to the examined eye side, a positive lens L21, a positive lens L22, a negative lens L23, and a positive meniscus lens L24 with its convex surface facing the scanning unit side. The lenses L22 and L23 are cemented together to form a meniscus lens component with its concave surface facing the examined eye 12 side.

[0083] The third lens group G3 includes, in order from the scanning unit side to the examined eye side, a positive lens L31, a negative meniscus lens L32 with a concave surface facing the scanning unit side, a lens L33 with a convex surface facing the scanning unit side, and a meniscus lens L34 with a convex surface facing the examined eye 12. The lenses L31 and L32 are cemented together to form a positive lens component. Here, the concave lens surface S3 with the strongest divergence power in the above-mentioned third lens group G3 is the concave surface of the negative lens L33 facing the examined eye side.

[0084] Table 2 shows the lens data of Example 2. [Table 2]

[0085] Figure 7 shows the lateral aberration of the objective lens configured with the specifications in Table 2. As is clear from the lateral aberration diagram shown in Figure 7, it is confirmed that the objective lens 130 of Example 2 suppresses variations in aberration for light in a wide wavelength range, including light in the visible wavelength range and light in the near-infrared range, and that the aberration is well corrected.

[0086] Example 3 FIG. 8 shows an example of the lens configuration of the objective lens 130 according to Example 3. Since the configuration is the same as in the first embodiment, the same parts are given the same reference numerals and detailed explanations are omitted.

[0087] The first lens group G1 includes, in order from the pupil conjugate position P1 side (scanning unit side) toward the subject's eye 12 side, a positive meniscus lens L11 with a concave surface facing the scanning unit side, a negative lens L12, a positive lens L13, a positive lens L14, and a negative lens L15 with a concave surface facing the scanning unit side. The lenses L12 and L13 are cemented together to form a meniscus lens component with a concave surface facing the scanning unit side. The lenses L14 and L15 are cemented together to form a meniscus lens component with a convex surface facing the scanning unit side.

[0088] The second lens group G2 includes, in order from the scanning unit side to the eye to be examined, a positive lens L21, a positive lens L22, a negative lens L23, and a positive meniscus lens L24 with its convex surface facing the scanning unit side. The lenses L22 and L23 are cemented together to form a meniscus lens component with its convex surface facing the scanning unit side.

[0089] The third lens group G3 includes, in order from the scanning unit side to the examined eye side, a positive lens L31, a negative lens L32, a meniscus lens L33 with its concave surface facing the scanning unit side, and a meniscus lens L34 with its concave surface facing the scanning unit side. The lenses L31 and L32 are cemented together to form a meniscus lens component with its convex surface facing the scanning unit side. Here, the concave lens surface S3 of the third lens group G3, which has the strongest divergence power, is the concave surface of the meniscus lens L33 facing the examined eye side.

[0090] Table 3 shows the lens data of Example 3. [Table 3]

[0091] Figure 9 shows the lateral aberration of the objective lens configured with the specifications in Table 3. As is clear from the lateral aberration diagram shown in Figure 9, it is confirmed that the objective lens 130 of Example 3 suppresses variations in aberration for light in a wide wavelength range, including light in the visible wavelength range and light in the near-infrared range, and that the aberration is well corrected.

[0092] Example 4 FIG. 10 shows an example of the lens configuration of the objective lens 130 according to the fourth embodiment. 4 has the same configuration as in the first embodiment, the same parts are given the same reference numerals and detailed explanations are omitted.

[0093] The first lens group G1 includes, in order from the pupil conjugate position P1 side (scanning unit side) toward the subject's eye 12 side, a negative meniscus lens L11 with its convex surface facing the scanning unit side, a positive lens L12, a negative lens L13, a positive lens L14, and a positive lens L15. The lenses L11 and L12 are cemented together to form a biconvex positive lens component. Furthermore, the ninth surface of the lens L15, which faces the subject's eye 12, is formed as an aspheric surface.

[0094] The second lens group G2 includes, in order from the scanning unit side to the eye to be examined, a positive lens L21, a positive lens L22, a negative lens L23, and a positive meniscus lens L24 with its convex surface facing the scanning unit side. The lenses L22 and L23 are cemented together to form a meniscus lens component with its convex surface facing the scanning unit side.

[0095] The third lens group G3 includes, in order from the scanning unit side to the examined eye side, a positive lens L31, a negative meniscus lens L32 with a concave surface facing the scanning unit side, a meniscus lens L33 with a convex surface facing the scanning unit side, a negative lens L34, and a positive lens L35. The lenses L31 and L32 are cemented together to form a biconvex positive lens component. The lenses L34 and L35 are cemented together to form a meniscus lens component with a concave surface facing the scanning unit side. Here, the concave lens surface S3 with the strongest divergence power in the third lens group G3 is the concave surface of the negative lens L33 facing the examined eye side.

[0096] Table 4 shows the lens data of Example 4. [Table 4]

[0097] The aspherical surfaces listed in Table 4 are expressed by the equation below, where h is the height in the direction perpendicular to the optical axis, zs is the distance along the optical axis from the tangent plane at the vertex of the aspherical surface to the position on the aspherical surface at height h, c is the inverse of the paraxial radius of curvature, k is the conic coefficient, A is the fourth-order aspherical coefficient, B is the sixth-order aspherical coefficient, C is the eighth-order aspherical coefficient, D is the tenth-order aspherical coefficient, and E is the twelfth-order aspherical coefficient. zs=(c·h 2 ) / 〔1+{1-(1+k)·h 2 ·c 2} 1 / 2 〕 +A·h 4 +B·h 6 +C·h 8 +D·h 10 +E·h 12 +···

[0098] Table 5 shows the aspherical coefficients of the aspherical surface of Example 3. In the table, the aspherical coefficients A to are expressed in degrees. "En" (n is an integer) in the table indicates "×10 -n " means. [Table 5]

[0099] FIG. 11 shows the lateral aberration of the objective lens configured according to the specifications in Tables 4 and 5. As is clear from the lateral aberration diagram shown in Figure 11, it is confirmed that the objective lens 130 of Example 4 suppresses variations in aberration for light in a wide wavelength range, including light in the visible wavelength range and light in the near-infrared range, and that the aberration is well corrected.

[0100] Next, the suitability of the above conditional expressions for the objective lenses in each of the above-mentioned Examples 1 to 4 will be described. Table 6 shows values ​​related to the above-mentioned conditional expressions for each of Examples 1 to 4. [Table 6]

[0101] As is clear from Table 6, the objective lenses of Examples 1 to 4 meet the above-mentioned conditional expressions.

[0102] Second Embodiment Next, a second embodiment will be described. In the second embodiment, the objective lens 130, which is a main part of the imaging optical system 116A according to the first embodiment, is formed as an attachment optical system that can be attached to and detached from a portable terminal having an imaging function. The configuration of the second embodiment is substantially the same as that of the first embodiment, so the same parts are given the same reference numerals and their description will be omitted, and the differences will mainly be described.

[0103] FIG. 12 shows an example of a configuration in which the attachment optical system 300 according to the second embodiment can be attached to and detached from a mobile terminal 400 having a photographing function.

[0104] As shown in FIG. 12, the mobile terminal 400 includes a photographing unit 402 for realizing a photographing function. The photographing unit 402 is configured to operate in a normal photographing mode for photographing an object at infinity, such as a landscape, by user operation of an operation unit (not shown) provided on the mobile terminal 400. That is, the photographing unit 402 of the mobile terminal 400 is provided with a mobile terminal lens 404 (FIG. 13), and is configured to form an image on the image sensor 406 (FIG. 13) when parallel light is incident thereon in the normal photographing mode.

[0105] Fig. 13 shows an example of the configuration of an attachment optical system 300 according to the second embodiment. Fig. 13 shows the attachment optical system 300 attached to a mobile terminal 400. The attachment optical system 300 includes a first lens group G1, a second lens group G2, and a third lens group G3 that constitute the objective lens 130 described above. The configuration and function of each of these lens groups are the same as those in the first embodiment, and therefore detailed description thereof will be omitted.

[0106] The attachment optical system 300 according to the second embodiment differs from the objective lens 130 according to the first embodiment in that it includes an illumination unit 304 that irradiates illumination light and a half mirror 302 that guides the illumination light from the illumination unit to an optical path along the optical axis AX. The illumination unit 304 irradiates illumination light that illuminates the subject's eye 12. The half mirror 302 guides the illumination light from the illumination unit 304 to an optical path along the optical axis AX.

[0107] If mobile terminal 400 is equipped with a subject illumination unit that illuminates a subject, attachment optical system 300 may be equipped with an optical system that collects illumination light emitted from the subject illumination unit and guides the illumination light from the subject illumination unit to an optical path along optical axis AX, instead of illumination unit 304 and half mirror 302. Furthermore, illumination unit 304 may be configured independently of attachment optical system 300.

[0108] The attachment optical system 300 includes an attachment section 306 for attaching the attachment optical system 300 to the portable terminal 400 so that the attachment optical system 300 and the portable terminal 400 can be detachably connected to each other. By including this attachment section 306 in the attachment optical system 300, the attachment optical system 300 can be detachably connected to the portable terminal 400.

[0109] The first lens group G1 and the second lens group G2 included in the attachment optical system 300 function as an objective optical system 301 that forms a pupil conjugate with the pupil of the subject's eye 12. The attachment optical system 300 and the portable terminal 400 are fixed by the mounting unit 306 so that the entrance pupil of the photographing unit 402 of the portable terminal 400 is positioned at the position of the pupil conjugate with the pupil of the subject's eye 12 formed by the objective optical system 301 (pupil conjugate position P1). With this configuration, it is possible to take a fundus image of the subject's eye 12 with a simple configuration in which the attachment optical system 300 is simply attached to the portable terminal 400.

[0110] Third Embodiment Next, a third embodiment will be described. In the first embodiment, the photographing optical system 116A, which functions as a posterior-segment observation optical system for observing the posterior segment of the subject's eye 12, has been mainly described. In the third embodiment, an optical module for anterior-segment observation is inserted into the photographing optical system 116A, which functions as a posterior-segment observation optical system according to the first embodiment, so that the photographing optical system 116A can be switched to function as an anterior-segment observation optical system for observing the anterior segment of the subject's eye 12. The configuration of the third embodiment is substantially the same as that of the first embodiment, and therefore the same parts are denoted by the same reference numerals and their description will be omitted, and the following mainly describes the different parts.

[0111] FIG. 14 shows an example of the configuration of the objective lens 130 in the imaging optical system 116A according to the third example. The imaging optical system 116A according to the third embodiment includes an objective lens 130 that can be switched between a posterior eye segment observation optical system and an anterior eye segment observation optical system. The objective lens 130 is connected to a scanning unit (e.g., a water In order from the flat scanning unit 142 side, it comprises a first lens group 134 and a second lens group 132, and a third lens group 133 is provided in the space between the first lens group 134 and the second lens group 132. The configurations of the first lens group 134 (G1), the second lens group 132 (G2), and the third lens group 133 (G3) are the same as those in the first embodiment, so detailed description will be omitted.

[0112] The photographing optical system 116A includes an optical module 136 for anterior-segment observation that is insertable into and removable from the optical path of the objective lens 130. By disposing the optical module for anterior-segment observation in the optical path of the objective lens 130, it is possible to switch from the optical system for posterior-segment observation to the optical system for anterior-segment observation. Specifically, as shown in Fig. 14, the optical module 136 for anterior-segment observation is inserted into the optical path of the objective lens 130, for example, in the optical path between a first lens group 134 (G1) with positive refractive power and a second lens group 132 (G2) with positive refractive power that constitute the objective lens 130. Preferably, as shown in Fig. 14, the optical module 136 is inserted into the optical path between the second lens group 132 (G2) and the third lens group 133 (G3).

[0113] The optical module 136 has optical elements therein, including a lens 162 having negative power as a switching lens. When the lens 162 is positioned on the optical axis of the objective lens 130, the lens 162 functions as a switching lens for switching the posterior eye observation optical system 300 to the anterior eye observation optical system 400. When the lens 162 is inserted into the optical path of the objective lens 130, the scanning position (scanning center position Ps) of the scanning unit (e.g., the horizontal scanning unit 142) and the pupil position P3 of the subject's eye 12 are not conjugate, and parallel light from the scanning position of the scanning unit is focused on the anterior eye. The diameter of the light beam passing through the lens 162 is smaller than the diameter of the light beam passing through each of the first lens group 134 and the second lens group 132. Therefore, the effective diameter of the lens 162 is smaller than the effective diameters of the lens groups constituting the objective lens 130. This allows the optical module 136 to be configured in a compact size. The optical element is not limited to the negative power lens 162, and instead of the lens 162, an optical member such as a Fresnel lens or a DOE (Diffractive Optical Element) may be used.

[0114] More specifically, the imaging optical system 116A is configured so that an optical module 136 for observing the anterior segment of the eye can be inserted into or removed from the optical path of the objective lens 130, which is the optical path of the observation optical system for observing the posterior segment of the eye, manually or automatically by an operator (e.g., an ophthalmologist). When the optical module 136 is not disposed in the optical path of the objective lens 130, a posterior segment observation optical system is configured as the observation optical system, and the ophthalmic apparatus 110 thereby acquires an image of the posterior segment of the eye 12 to be examined. On the other hand, when the optical module 136 is inserted into the optical path of the objective lens 130, an anterior segment observation optical system is configured as the observation optical system, and the ophthalmic apparatus 110 thereby acquires an image of the anterior segment of the eye 12 to be examined.

[0115] The optical module 136 for observing the anterior segment may be equipped with an eye tracking module that tracks the gaze direction used when observing the anterior segment, a fixation light that guides the gaze direction of the subject's eye 12, a camera, and a lighting device.

[0116] As described above, according to the third embodiment, by inserting and removing the optical module 136 for observing the anterior segment into and from the optical path of the objective lens 130, which functions as an observation optical system for observing the posterior segment, the photographing optical system 116A can be instantly switched between an anterior segment observation optical system for observing the anterior segment of the subject's eye 12 and a posterior segment observation optical system for observing the posterior segment.

[0117] Preferred Embodiments Next, an example of the objective lens 130 according to the third embodiment will be described.

[0118] Example 5 FIG. 15 shows an example of the lens configuration of the objective lens 130 according to Example 5. Since Example 5 has the same configuration as Example 2, the same parts are denoted by the same reference numerals and detailed description thereof will be omitted. Example 5 differs from Example 2 in that a lens 136 included in an optical module 136 for observing the anterior segment of the eye is added between the second lens group 132 and the third lens group 133 in the configuration of Example 2.

[0119] In the fifth embodiment, the negative lens L41 is disposed between the second lens group G2 and the third lens group 133, specifically, between the positive lens L21 and the negative lens L34.

[0120] Table 7 shows the lens data for Example 5. [Table 7]

[0121] Although not shown in the figures, the objective lens 130 of Example 5 has good aberration correction for light in the wavelength range for anterior eye photography (visible light wavelength range or near-infrared range) even when an optical module 136 for anterior eye observation is inserted into the optical path of the objective lens 130, which functions as an observation optical system for posterior eye observation.

[0122] [Fourth embodiment] Next, a fourth embodiment will be described. The configuration of the fourth embodiment is substantially the same as the above-described embodiments, so the same parts are given the same reference numerals and the description thereof will be omitted.

[0123] In the above embodiments, the objective lens 130 included in the imaging optical system 116A for observing the subject's eye 12 can suppress aberration variations for light in a wide wavelength range, including light in the visible wavelength range and light in the near-infrared range. Therefore, the objective lens 130 according to each of the above embodiments can be applied to ophthalmic apparatuses dedicated to SLO and OCT. In addition, the objective lens 130 can be applied (shared) as a common objective lens for SLO and OCT in a combining apparatus having the functions of both SLO and OCT. In the fourth embodiment, the objective lens 130 is used in common for SLO and OCT.

[0124] Because the wavelengths of light used in the SLO optical system and the OCT optical system differ, it is preferable to adjust the lens configuration for each. Therefore, in the fourth embodiment, since the objective lens 130 is used in common, the objective lens is configured with two lens groups, and the difference between the SLO optical system and the OCT optical system is absorbed by one of the lens groups (for example, the first lens group G1) using the SLO objective lens as a reference. Specifically, the objective lens is configured with two lens groups, and the front lens group (the second lens group G2) is used in common, and the configuration of the rear lens group (the first lens group G1) is changed, so that the relay lens device for SLO functions as a relay lens device for OCT.

[0125] FIG. 16 shows an example of the configuration of the objective lens 130 in the imaging optical system 116A according to the fourth embodiment. As shown in Fig. 16, the objective lens 130 according to the fourth embodiment forms an area in the optical path where substantially parallel light propagates, and a separation / combination element (e.g., a dichroic mirror) DM1 that separates or combines the optical path is disposed in the formed area. In the example shown in Fig. 16, a parallel optical system is formed between the first lens group G1 and the third lens group G3. In this case, the first lens group G1 forms a lens group such that the light traveling from the first lens group G1 to the third lens group G3 becomes parallel.

[0126] The third lens group G3 is formed so as to direct the collimated light from the first lens group G1 to an intermediate pupil position P3. Specifically, the third lens group G3 includes, in order from the scanning unit side, lens group G31, lens group G32, and lens group G33. The lens group G31 is a lens group that functions to form an intermediate pupil within the third lens group G3 from the collimated light from the first lens group G1. The lens group G32 is a lens group that has a concave surface at or near the intermediate pupil position P3. The lens group G33 is a lens group that functions to transfer the intermediate pupil toward the second lens group.

[0127] 16 is used as the optical path for the SLO, and a separation / combination element DM1 is placed in the region between the first lens group G1 and the third lens group G3 and used as the optical path for the OCT. In this way, it becomes possible to combine two optical systems, the SLO and the OCT. In this way, in the fourth embodiment, an area that propagates approximately parallel light is formed in the optical path of the objective lens 130, and a separation / combination element DM1 that separates the optical path is placed in the formed area, making it possible to combine two optical systems, SLO and OCT.

[0128] In the fourth embodiment, a dichroic mirror or the like is used in the optical path of OCT in a region where substantially parallel light propagates. However, the region where substantially parallel light propagates is not limited to the region between the first lens group G1 and the third lens group G3. For example, a separation / combining element may be provided in any space between the first lens group G1 and the third lens group G3 of the objective lens 130 according to each of the above embodiments. Furthermore, in the fourth embodiment, a separation / combining element DM1 is provided in a region where substantially parallel light propagates. However, this is not limiting. For example, a separation / combining element DM2 may be provided in a region between the lens group G31 and the lens group G32 in the third lens group G3, a separation / combining element DM3 may be provided in a region between the lens group G32 and the lens group G33, and a separation / combining element DM4 may be provided in a region between the third lens group G3 and the second lens group G2.

[0129] In the configuration shown in FIG. 16, it is of course possible to use the optical path including the optical axis AX as the optical path for OCT, and to arrange a separation / combination element DM1 and use it as the optical path for SLO.

[0130] Note that if an optical element (separation / combination element DM4) is placed between the second lens group G2 and the third lens group G3, flare may occur in the visible light range. Therefore, if an optical element (separation / combination element DM4) is placed between the second lens group G2 and the third lens group G3 to separate the optical path, it is preferable to use it as the optical path for OCT.

[0131] As described above, according to the fourth embodiment, the objective lens 130 can be used as a synthesizing device having both the functions of SLO and OCT.

[0132] Fifth Embodiment Next, a fifth embodiment will be described. The configuration of the fifth embodiment is substantially the same as that of the fourth embodiment, so the same parts are given the same reference numerals and the description thereof will be omitted.

[0133] Ophthalmic devices may include a fixation target projection optical system that presents a fixation target using a fixation lamp and a subject's eye position imaging optical system that images the position of the subject's eye 12 using a camera or the like. These observation optical systems, such as the fixation target projection optical system and the subject's eye position imaging optical system, are sufficient in terms of imaging performance by appropriately correcting primarily the visible range. On the other hand, the objective lens 130 of the present disclosure provides excellent aberration correction over a wide wavelength range, including both the visible range for SLO and the near-infrared range for OCT. In this case, the objective lens 130 can be configured to perform aberration correction primarily in the visible range on the subject's eye 12 side of the pupil conjugate position P3 in the objective lens 130, and to perform aberration correction in the near-infrared range by an optical system on the scanning unit side of the pupil conjugate position P3. In other words, it is possible to separate the wavelength range for aberration correction into multiple wavelength ranges and perform aberration correction in different wavelength ranges in each. For example, the second lens group G2 is used as the optical system closer to the subject's eye 12 than the intermediate pupil conjugate position P3, and the first lens group G1 is used as the optical system closer to the scanning unit than the intermediate pupil conjugate position P3. When combining the optical paths of the observation optical systems, such as the fixation target projection optical system and the subject's eye position photographing optical system, an optical path combining prism can be placed in the third lens group G3 in the area before and after the pupil conjugate position P3 (the area where the separating / combining element DM2 or DM3 shown in FIG. 16 is placed). To take into consideration the influence of aberrations in the visible range, it is preferable to place the optical path combining prism that combines the optical paths in the area where the separating / combining element DM3 is placed. Furthermore, when infrared light is used in the subject's eye position photographing optical system, it is effective to place the optical path combining prism at the position of DM1 on the scanning unit side in FIG. 16. In any case, when a light path combining prism is placed between the subject's eye pupil P2 and the pupil conjugate position P1 where the scanning unit is placed, it is important to balance the aberration correction functions of each group of the three-group objective lens.

[0134] As described above, according to the fifth embodiment, the ophthalmologic apparatus 110 can be provided with an observation optical system, such as a fixation target projection optical system and an examination eye position photographing optical system, with a simple configuration.

[0135] Sixth Embodiment Next, a sixth embodiment will be described. The configuration of the sixth embodiment is substantially the same as the above-described embodiments, so the same parts are given the same reference numerals and the description thereof will be omitted.

[0136] In the above embodiments, the objective lens 130 included in the imaging optical system 116A for observing the subject's eye 12 can suppress aberration variations for light in a wide wavelength range, including light in the visible wavelength range and light in the near-infrared range. Therefore, the objective lens 130 according to each of the above embodiments can be applied to an ophthalmic apparatus dedicated to SLO, and the SLO-dedicated ophthalmic apparatus can be switched from an SLO ophthalmic apparatus to an OCT ophthalmic apparatus for use. In the sixth embodiment, the SLO-dedicated ophthalmic apparatus is configured to be switchable from an SLO ophthalmic apparatus to an OCT ophthalmic apparatus.

[0137] FIG. 17 shows an example of the configuration of an ophthalmologic apparatus 110A according to the sixth embodiment. 17, an ophthalmic apparatus 110A according to the sixth embodiment includes a relay lens device 140 dedicated to SLO that relays scanning light from an SLO unit, and an objective lens 130 (see also FIG. 2), and is configured as a dedicated SLO device. The relay lens device 140 is disposed in a relay unit 140A that is detachable from the ophthalmic apparatus 110A. That is, by attaching the relay unit 140A to a relay lens attachment portion (not shown) of the ophthalmic apparatus 110A, the ophthalmic apparatus 110A functions as a dedicated SLO device.

[0138] Meanwhile, a relay unit 140B can be attached to a relay lens attachment portion (not shown) of the ophthalmic apparatus 110A. In the relay unit 140B, a dichroic mirror DM5 that separates and combines light is disposed in the optical path of the relay lens device 140. In addition, in the relay unit 140B, an OCT unit is disposed in the optical path separated by the dichroic mirror DM5. Therefore, by attaching the relay unit 140B to the relay lens attachment portion (not shown) of the ophthalmic apparatus 110A, the ophthalmic apparatus 110A can function as an SLO device as well as an OCT device.

[0139] Thus, according to the sixth embodiment, by replacing the relay lens device 140 of the SLO-dedicated machine with a relay lens 141 having the same components as the relay lens device 140 and incorporating a dichroic mirror DM5, and by attaching an OCT unit, an ophthalmic device can be made that can operate as both an SLO and OCT device.

[0140] Furthermore, by using a common objective lens 130 and a common lens configuration for the relay lens device 140 and the relay lens 141, an ophthalmic device capable of both SLO and OCT can be constructed from an SLO-only device, thereby enabling significant cost reductions.

[0141] Although the above describes the case where the relay unit is attached to a relay lens attachment portion (not shown), the relay lens device 140 may be formed of a plurality of lens groups, the relay lens device 140 may be fixed to the ophthalmic apparatus 110A, and the dichroic mirror DM5 may be configured to be inserted and removed into the space between adjacent lens groups. In this case, replacement of the relay lens device 140 is not necessary, which further reduces costs.

[0142] As such, the technology of the present disclosure includes a function for configuring an ophthalmic apparatus capable of both SLO and OCT from an ophthalmic apparatus that functions as an SLO-only apparatus, and therefore includes the following first technology. (1st technology) a first optical path having a scanning unit for angularly scanning a light beam from a first light source; an objective lens that guides the scanning light beam from the scanning unit to the subject's eye; The scanning light beam from the scanning unit is guided to the objective lens. a relay lens for guiding the light to the lens; The relay lens includes two lens groups and an optical element for combining and separating optical paths that can be inserted and removed between the two lens groups, and a second optical path is configured on a reflected optical path of the optical element for combining and separating optical paths, with the optical element for combining and separating optical paths being disposed in the optical path, to guide a light beam from a second light source different from the first light source to the objective lens. Ophthalmology equipment.

[0143] The dichroic mirror DM5 is an example of the optical element for combining and separating optical paths in the first technique.

[0144] Furthermore, the optical system of the first technique includes an aberration correction technique, and therefore includes the following Supplementary Technique 1 and Supplementary Technique 2. (Supplementary Technology 1 of Technology 1) In a first composite optical system including the relay lens and the objective lens, a first aberration correction is made to the light beam from the first light source, and in a second composite optical system including the objective lens and a lens group on the objective lens side of the two lens groups constituting the relay lens, a second aberration correction different from the first aberration correction is made to the light beam from the second light source. First technology ophthalmic device.

[0145] (Supplementary Technology 2 of Technology 1) The objective lens is subjected to aberration correction for the light beam from the first light source and the light beam from the second light source, and the relay lens of the first optical path and the relay lens of the second optical path are common lens components. First technology ophthalmic device.

[0146] Seventh Embodiment Next, a seventh embodiment will be described. The configuration of the seventh embodiment is substantially the same as the above-described embodiment, so the same parts are given the same reference numerals and the description thereof will be omitted.

[0147] The technology disclosed herein includes, as an ophthalmic apparatus, at least one of the following optical systems: an SLO optical system using light mainly having wavelengths in the visible range; an OCT optical system using light mainly having wavelengths in the near-infrared range; and an alignment optical system used for aligning the subject's eye. The alignment optical system includes a fixation target projection optical system and a subject's eye position photographing optical system. Each of these optical systems may have aberration correction for the lens system that differs from that of the SLO optical system or the OCT optical system. Therefore, in the seventh embodiment, an example configuration of an ophthalmic apparatus that takes into account aberration correction in the objective lens will be described.

[0148] (First configuration example) The ophthalmic apparatus as the first configuration example is an SLO ophthalmic apparatus equipped with an objective lens that is corrected for chromatic aberration at least in the visible range. An optical system including this objective lens that is corrected for chromatic aberration in the visible range will be described.

[0149] FIG. 18 shows an example of the configuration of the imaging optical system 116B in the ophthalmologic apparatus according to the first configuration example. As shown in Fig. 18, the ophthalmologic apparatus according to the first configuration example functions as a dedicated SLO device. Specifically, the imaging optical system 116B includes, in order from the subject's eye 12 side, an objective lens 1130 corrected for chromatic aberration in the visible range, a horizontal scanning unit (also referred to as an H scanner in Fig. 18) 142, a relay lens device 140, and a vertical scanning unit (also referred to as a V scanner in Fig. 18) 120 such as a polygon mirror.

[0150] The horizontal scanning unit 142 is an optical scanner that horizontally scans the SLO laser light incident via the relay lens device 140. The vertical scanning unit 120 is an optical scanner that vertically scans the laser light incident from the SLO unit 18. In this embodiment, a galvanometer mirror is used as an example of the horizontal scanning unit 142, and a polygon mirror is used as an example of the vertical scanning unit 120.

[0151] The relay lens device 140 includes two lens groups 144 and 146 each having a positive power. The two lens groups 144 and 146 configure the relay lens device 140 so that the position of the vertical scanning unit 120 and the position of the horizontal scanning unit 142 are conjugate. More specifically, the relay lens device 140 is configured so that the central positions of the angular scanning of both scanning units are conjugate. The relay lens device 140 is also configured to include a position conjugate with the fundus of the subject's eye 12. Furthermore, the positions of the vertical scanning unit 120 and the horizontal scanning unit 142 are configured so that they are conjugate with the pupil of the subject's eye 12.

[0152] The light emitted from the SLO unit 18 is two-dimensionally scanned by the vertical scanning unit 120 and horizontal scanning unit 142 that constitute the SLO optical system. The two-dimensionally scanned SLO laser light is incident on the subject's eye 12 via the objective lens 1130. The SLO laser light reflected by the subject's eye 12 is incident on the SLO unit 18 via the objective lens 1130, the horizontal scanning unit 142, the relay lens device 140, and the vertical scanning unit 120.

[0153] The objective lens 1130 includes, in order from the horizontal scanning unit 142 side, a first lens group G1 and a second lens group G2, where at least the second lens group G2 is a positive lens group having a positive overall power. In this embodiment, the first lens group G1 is also a positive lens group having a positive overall power. Each of the first lens group G1 and the second lens group G2 includes at least one positive lens. When each of the first lens group G1 and the second lens group G2 includes multiple lenses, each of the first lens group G1 and the second lens group G2 may include a negative lens as long as it has a positive overall power. The objective lens 1130 is configured to include a position conjugate with the fundus of the subject's eye 12.

[0154] With the above configuration, it is possible to provide an ophthalmic apparatus dedicated to SLO.

[0155] (Second configuration example) In the ophthalmic apparatus as the second configuration example, chromatic aberration correction is performed in the objective lens for SLO at least in the visible range. An optical system including this objective lens with chromatic aberration correction in the visible range will be described.

[0156] FIG. 19 shows an example of the configuration of the imaging optical system 116C in the ophthalmologic apparatus according to the second configuration example. 19, the ophthalmologic apparatus according to the second configuration example has the function of being operable in both SLO and OCT. The ophthalmologic apparatus according to the second configuration example also includes an alignment optical system. Specifically, based on the optical system functioning as SLO, the imaging optical system 116C includes, in order from the subject's eye 12 side, an objective lens 1130 corrected for chromatic aberration in the visible range, a horizontal scanning unit (H scanner) 142, a relay lens device 140 for SLO, and a vertical scanning unit (V scanner) 120 such as a polygon mirror.

[0157] As mentioned above, the wavelengths of light used in the SLO optical system and the OCT optical system are different, so it is preferable to adjust the lens configuration to suit each. In the second configuration example, the SLO optical system and the OCT optical system use a common objective lens 1130, so the relay lens device absorbs the difference in aberration correction. Specifically, the relay lens device is made up of two lens groups. The relay lens device 1140 is configured to function as a relay lens device for OCT by using a common front lens group (for example, the lens group 144 on the objective lens 1130 side of the relay lens device 1140 for SLO) and configuring the lens group 1146 on the scanner 142 side differently from the lens group 1146A on the OCT side. Furthermore, the scanning units that scan the OCT light are also different. Therefore, in the second configuration example, a relay lens device 1140 having a similar configuration to the relay lens device 140 for SLO is provided between the objective lens 1130 and the horizontal scanning unit (H scanner) 142. The relay lens device 1140 includes, in order from the subject's eye 12 side, a front lens group 1144 and a rear lens group 1146, and a beam splitter 1148 that reflects the OCT light and the light reflected from the fundus between the lens groups 1144 and 1146. Specifically, the relay lens device 1140 includes multiple lenses 1144 and 1146 having positive power, similar to the relay lens device 140, and is configured to include a position conjugate with the fundus of the subject's eye 12. On the reflection side of the beam splitter 1148, i.e., on the reflection side of the light reflected from the fundus, a lens group 1146A corresponding to the lens group 1146 in the relay lens device 1140 for SLO and having aberration correction for OCT, and an OCT scanning unit 1142 are arranged in this order. That is, in OCT, XY scanning is performed independently of the SLO. The OCT scanning unit 1142 is also arranged at a position conjugate with the pupil of the subject's eye 12.

[0158] Furthermore, since the photographing optical system 116C includes an alignment optical system, a beam splitter 178 that guides the optical path of the alignment optical system 138H is provided between the objective lens 1130 and the relay lens device 1140. That is, in the photographing optical system 116C, the beam splitter 178 is inserted into the optical path of the optical system that functions as the SLO, and the alignment optical system 138H, which includes a fixation target projection optical system 138HA, a subject's eye position photographing optical system 138HB, and an illumination device 138HC, is provided on the reflection side of the beam splitter 178. The beam splitter 178 is also disposed at a position conjugate with the pupil of the subject's eye 12.

[0159] With the above configuration, the objective lens 1130 for SLO can also be used for OCT.

[0160] (Third configuration example) The ophthalmic apparatus as the third configuration example is an ophthalmic apparatus dedicated to OCT, which uses an objective lens for SLO that has been corrected for chromatic aberration at least in the visible range as an objective lens for OCT.

[0161] FIG. 20 shows an example of the configuration of the imaging optical system 116D in the ophthalmologic apparatus according to the third configuration example. 20 , the ophthalmologic apparatus according to the third configuration example functions as a dedicated OCT device. Specifically, the imaging optical system 116D includes, in order from the subject's eye 12 side, an objective lens 1130 corrected for chromatic aberration in the visible range, a relay lens device 1140 including a beam splitter 1148, a lens group 1146A on the reflection side of the beam splitter 1148 that has been corrected for aberrations for OCT, and an OCT scanning unit 1142. The fundus camera optical system Fundus is provided on the transmission side of the relay lens device 1140. The fundus camera optical system Fundus is positioned conjugate with the pupil of the subject's eye 12.

[0162] With the above configuration, it is possible to provide an ophthalmic apparatus dedicated to OCT using the objective lens 1130 for SLO.

[0163] (Fourth configuration example) The ophthalmic apparatus as the fourth configuration example is an SLO ophthalmic apparatus equipped with the objective lens 130 according to the first embodiment, that is, the objective lens 130 in which chromatic aberration is corrected in the visible and near-infrared ranges.

[0164] FIG. 21 shows an example of the configuration of the imaging optical system 116E in the ophthalmologic apparatus according to the fourth configuration example. 21, the ophthalmologic apparatus according to the fourth configuration example functions as a dedicated SLO device. Specifically, the imaging optical system 116E includes, in order from the subject's eye 12 side, the objective lens 130 according to the first embodiment, i.e., the objective lens 130 corrected for chromatic aberration in the visible and near-infrared ranges, a horizontal scanning unit 142, a relay lens device 140, and a vertical scanning unit 120.

[0165] As explained in FIG. 3, the objective lens 130 includes, in order from the horizontal scanning unit 142 side, a first lens group G1 and a second lens group G2, and a third lens group G3 between the first lens group G1 and the second lens group G2. The objective lens 130 is configured to include a position conjugate with the pupil of the subject's eye 12 within the third lens group G3, and also to include a position conjugate with the fundus of the subject's eye. Note that in FIG. 21, the three lens groups in the objective lens 130 are simply indicated as G1, G2, and G3. These are the three lens groups 134, 132, and 133 shown in FIG. 3. This corresponds to 3. The same applies to the following figures.

[0166] In this way, by using the objective lens 130 with a built-in intermediate pupil, chromatic aberration is corrected in the visible and near-infrared ranges, and by reducing the maximum aperture of the objective lens 130 and preventing an increase in the weight of the objective lens 130, it is possible to provide an ophthalmic device dedicated to SLO that can reduce the weight of the entire device.

[0167] (Fifth configuration example) The ophthalmic apparatus as the fifth configuration example is an ophthalmic apparatus equipped with SLO and OCT, which includes an objective lens 130 that is corrected for chromatic aberration in the visible and near-infrared regions.

[0168] Fig. 22 shows an example of the configuration of the imaging optical system 116F in an ophthalmic apparatus according to the fifth configuration example. As shown in Fig. 22, the ophthalmic apparatus according to the fifth configuration example has the function of being operable in both SLO and OCT. The fifth configuration example shown in Fig. 22 differs from the second configuration example shown in Fig. 19 in that the objective lens 1130 is replaced with an objective lens 130 that has been corrected for chromatic aberration in the visible and near-infrared ranges.

[0169] With the above configuration, it is possible to share the objective lens for both SLO and OCT.

[0170] (Sixth configuration example) The ophthalmic apparatus as the sixth configuration example is an ophthalmic apparatus dedicated to OCT, which uses an objective lens 130 that has been corrected for chromatic aberration in the visible and near-infrared regions as an objective lens for OCT.

[0171] FIG. 23 shows an example of the configuration of a photographing optical system 116G in an ophthalmologic apparatus according to the sixth configuration example. As shown in Fig. 23, an ophthalmic apparatus according to the sixth configuration example functions as a dedicated OCT device. The sixth configuration example shown in Fig. 23 differs from the third configuration example shown in Fig. 20 in that the objective lens 1130 is replaced with an objective lens 130 that has chromatic aberration correction in the visible and near-infrared ranges. In this configuration, as described in Fig. 3, the objective lens 130 performs aberration correction for both the SLO optical system and the OCT optical system due to the aberration correction capability of the third lens group 133 (G3) as an intermediate group, so the relay lenses can be configured in exactly the same way.

[0172] With the above configuration, it is possible to provide an ophthalmic apparatus dedicated to OCT in which chromatic aberration is corrected from the visible range to the near-infrared range.

[0173] (7th configuration example) The ophthalmic apparatus as the seventh configuration example is an ophthalmic apparatus that functions in both SLO and OCT using an objective lens 130 that has been corrected for chromatic aberration in the visible and near-infrared ranges.

[0174] FIG. 24 shows an example of the configuration of the imaging optical system 116H in the ophthalmologic apparatus according to the seventh configuration example. 24, the ophthalmologic apparatus according to the seventh configuration example functions as an SLO device and an OCT device. Specifically, the photographing optical system 116H includes, in order from the subject's eye 12 side, an objective lens 130 including a first lens group G1 to a third lens group G3, which is chromatically corrected from the visible range to the near-infrared range, a horizontal scanning unit 142, a relay lens device 140, and a vertical scanning unit 120, thereby constituting an optical system for SLO.

[0175] To accommodate the difference in aberration correction due to the difference in scanning light between SLO and OCT, in the seventh configuration example, the optical system for SLO is used as a reference and the configuration of the first lens group G1 of the objective lens 130 is adjusted to be compatible with the optical system for OCT (see also FIG. 16 ). That is, the first lens group G1 and the third lens group G3 are configured to propagate substantially parallel light, and a splitting / combining element (e.g., a dichroic mirror) DM1 is disposed in the optical path. On the reflection side of the splitting / combining element DM1, a lens group 134A corresponding to the first lens group G1 of the objective lens functioning as SLO and having aberration correction for OCT, and an OCT scanning unit 1142A are disposed in this order. That is, in the OCT, XY scanning is performed independently of the SLO. Furthermore, the OCT scanning unit 1142A is disposed at a position conjugate with the pupil of the subject's eye 12. This configuration makes it possible to combine the two optical systems, SLO and OCT, while taking into account the aberrations of each optical system.

[0176] The ophthalmologic apparatus of the seventh configuration example also includes an alignment optical system 138H. Specifically, the optical path synthesis prism is disposed in either an area before or after the pupil conjugate position P3 in the third lens group G3. In the example shown in Fig. 24, the optical path synthesis prism is disposed in front of the pupil conjugate position (the area where the separation / synthesis element DM1 shown in Fig. 16 is disposed). With this configuration, it is possible to appropriately position at least one of the optical systems, the fixation target projection optical system 138HA and the subject's eye position photographing optical system 138HB.

[0177] With the above configuration, it is possible to provide an ophthalmic apparatus that functions as both an SLO and an OCT with appropriately corrected aberrations, and to provide an ophthalmic apparatus that includes the alignment optical system 138H.

[0178] As described above, the technology according to the seventh embodiment includes providing an ophthalmic apparatus including at least one of SLO, OCT, and an alignment optical system, and therefore includes the following second technology. (Second technology) a first scanning unit for scanning the light beam from the first light source; an afocal objective lens system that guides the scanning light beam from the first scanning unit to the eye to be examined; a first optical path including a first afocal relay system disposed between the first scanning unit and the objective lens and configured to guide the scanning light beam from the first scanning unit to the objective lens; a second scanning unit for scanning a light beam from a second light source different from the first light source; a second optical path having a second afocal relay system for guiding the scanning light beam from the second scanning unit to the subject's eye through the afocal objective lens system; The first afocal relay system and the second afocal relay system have a common beam splitter, and the first optical path and the second optical path are combined by the common beam splitter. Ophthalmology equipment.

[0179] The technology of the present disclosure also includes the following third technology. (Third technology) the first afocal relay system and the second afocal relay system each have two positive lens groups, and the common beam splitter is disposed between the two positive lens groups; The positive lens group of the first afocal relay system on the common afocal objective system side is configured in common with the positive lens group of the second afocal relay system on the common afocal objective system side. Second technology ophthalmic devices.

[0180] As described above, when a common objective lens is used for both SLO and OCT, there may be cases where aberration correction is performed for only one of the light sources, SLO or OCT, and the aberration correction for the other is considered insufficient. Therefore, the technology disclosed herein includes the following fourth technology. (4th technology) a positive lens group on the first scanner side of the first afocal relay system is different from a positive lens group on the second scanner side of the second afocal relay system, in the first optical path, aberration correction is performed on the light beam from the first light source in a composite system of the first afocal relay system and the common objective lens system, In the second optical path, in combining the second afocal relay system and the common objective lens system, Aberration correction is performed on the light beam from the second light source. Second technology ophthalmic devices.

[0181] Furthermore, the technique of the present disclosure includes the case where the common objective lens system has perfect aberration correction, and therefore includes the following fifth technique. (5th technology) the common objective lens system is aberration-corrected for both the light beam from the first light source and the light beam from the second light source, a positive lens group of the first afocal relay system on the first scanner side is the same as a positive lens group of the second afocal relay system on the second scanner side; in the first optical path, aberration correction is performed on the light beam from the first light source in a composite system of the first afocal relay system and the common objective lens system, In the second optical path, aberration correction is performed on the light beam from the second light source in a combination of the second afocal relay system and the common objective lens system. Second technology ophthalmic devices.

[0182] Furthermore, the technique of the present disclosure includes the case where the common objective lens system is a built-in pupil objective lens, and therefore includes the following sixth technique. (6th technology) The common objective lens system is a scanner-side positive first lens group G1; a positive second lens group G2 on the test eye side; and a third lens group G3 that is disposed between the two groups and includes a diverging surface. Second technology ophthalmic devices.

[0183] The techniques of the present disclosure also include the following seventh technique. (7th technology) The common objective lens system is A conjugate position (intermediate pupil position) with the scanning center of the scanner is formed between the first lens group G1 and the second lens group G2, and the third lens group G3 includes the intermediate pupil position. Second technology ophthalmic devices.

[0184] The techniques of the present disclosure also include the following eighth technique. (8th technology) a first scanner for scanning a light beam from a first light source; an afocal objective lens system that guides the scanning light beam from the first scanning unit to the eye to be examined; a first optical system including a first afocal relay system disposed between the first scanning unit and the afocal objective lens and configured to guide the scanning light beam from the first scanning unit to the afocal objective lens; a second scanning unit for scanning a light beam from a second light source different from the first light source; a second optical system having a second afocal relay system for guiding the scanning light beam from the second scanning unit to the subject's eye through the afocal objective lens system; The second afocal relay system has a beam splitter and is configured to be interchangeable with the first afocal relay system, and by switching the first afocal relay system to the second afocal relay system, the first optical system and the second optical system are combined via the beam splitter, making it possible to observe the eye to be examined using the first light source and the second light source. Ophthalmology equipment.

[0185] The techniques of the present disclosure also include the following ninth technique. (9th technology) The common objective lens system is aberration-corrected for both the light beam from the first light source and the light beam from the second light source, and the first afocal relay system and the second afocal relay system are the same. 8th technology ophthalmic device.

[0186] The techniques of the present disclosure also include the following tenth technique. (10th technology) The common objective lens system is a scanner-side positive first lens group G1; a positive second lens group G2 on the test eye side; and a third lens group G3 that is disposed between the two groups and includes a diverging surface. 8th technology ophthalmic device.

[0187] Although the technology of the present disclosure has been described using embodiments, the technical scope of the present disclosure is not limited to the scope described in the above embodiments. Various modifications or improvements can be made to the above embodiments without departing from the spirit of the invention, and such modifications or improvements are also included in the technical scope of the present disclosure. Furthermore, all documents, patent applications, and technical standards described in this specification are incorporated by reference in this specification to the same extent as if each individual document, patent application, and technical standard were specifically and individually indicated to be incorporated by reference. [Explanation of symbols]

[0188] 110 Ophthalmological equipment 17 Image processing device 20C First optical coupler 40, 42, 44, 46 light source 70, 72, 74, 76 Photodetector elements 132 First lens group 133 Third lens group 134 Second lens group 142 horizontal scanning unit 148 Vertical scanning unit

Claims

[Claim 1] An ophthalmic apparatus for observing an eye to be examined, A light source and a scanning unit that scans the light from the light source; an objective optical system that forms a pupil conjugate with the pupil of the subject's eye in the scanning unit; and The objective optical system comprises: In order from the scanning unit to the eye to be examined, a scanning unit side lens group; a subject-eye-side lens group, an intermediate pupil different from the pupil conjugate with the pupil of the eye to be examined is formed between the scanning unit side lens group and the eye to be examined side lens group; When W1 is the distance between the lens surface farthest from the subject's eye in the scanning unit side lens group and the position of the scanning unit, W2 is the distance between the lens surface closest to the subject's eye in the subject's eye side lens group and the pupil of the subject's eye, and D is the distance between the concave surface of a predetermined lens in the scanning unit side lens group or the subject's eye side lens group that is arranged closest to the intermediate pupil and the position of the intermediate pupil, D<W1, D<W2 Ophthalmic equipment that meets the above criteria.

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