Ophthalmic device

Abstract

An ophthalmic apparatus includes an illumination optical system having a slit formed with a slit-shaped opening portion and an iris diaphragm disposed at a position optically substantially conjugate with an iris of an eye to be examined between a light source and the slit and formed with two opening portions at positions separated from a position of an optical axis, generates slit-shaped illumination light using light from the light source, and guides the illumination light to a fundus of the eye to be examined, and a photographing optical system having a photographing diaphragm formed with an opening portion, guides return light of the illumination light guided through the opening portion of the photographing diaphragm from the fundus through a pupil split to an image sensor, and sets a width of the slit-shaped opening portion, a separation of the two opening portions, and a size of the opening portion of the photographing diaphragm in a manner that an overlapping region of a beam region of the illumination light and a beam region of the return light in the eye to be examined is disposed toward a fundus side from a posterior surface of a lens of the eye to be examined.

Description

TECHNICAL FIELD

[0001] The present application relates to an ophthalmic apparatus. BACKGROUND

[0002] In recent years, screening examinations using an ophthalmic apparatus are performed. Such an ophthalmic apparatus is also expected to be applied to self-tests, and further miniaturization and weight reduction are expected.

[0003] For example, in Patent Literature 1 and Patent Literature 2, an ophthalmic apparatus having a structure in which a test eye is pattern-illuminated, and its return light is received by an image sensor in a rolling shutter manner is disclosed. This ophthalmic apparatus is able to acquire an image of the test eye with a simple structure by adjusting the illumination pattern and the light-reception timing based on the image sensor.

[0004] In addition, for example, in Patent Literature 3, a fundus camera having a structure in which point-like illumination light is incident to a fundus and reflected light from the fundus is also point-like reduced, thereby reducing an area where the beam area of the illumination light in the lens and the beam area of the reflected light intersect.

[0005] Patent Literature 1: U.S. Patent No. 7831106 Specification

[0006] Patent Literature 2: U.S. Patent No. 8237835 Specification

[0007] Patent Literature 3: Japanese Patent Application Publication No. 2016-30181 SUMMARY

[0008] However, in the method disclosed in Patent Literature 1 and Patent Literature 2, there is a problem that the image quality of the test eye acquired is sometimes degraded even though the structure is simple, because a flare is generated due to the intersection of the beam area of the illumination light in the lens and the beam area of the reflected light.

[0009] On the contrary, according to the method disclosed in Patent Literature 3, it is possible to reduce the flare. However, there is a problem that it is necessary to irradiate the test eye with point-like illumination light, and thus it is necessary to change the existing structure, and the timing adjustment of the illumination side and the light-reception side becomes complicated. In addition, the photographing time becomes long, and the possibility of causing degradation of the image quality due to the eye movement of the test eye or the like is increased.

[0010] The present application was completed in view of such circumstances, and one of the objects thereof is to provide a new technology capable of acquiring a high-quality image of a test eye with a simple structure.

[0011] A first aspect of some embodiments is an ophthalmic apparatus including: an illumination optical system having a slit formed with a slit-like opening portion and an iris diaphragm disposed at a position optically substantially conjugate with an iris of an eye to be examined between a light source and the slit and formed with two opening portions at a position separated from a position of an optical axis, the illumination optical system generating slit-like illumination light using light from the light source and guiding the illumination light to a fundus of the eye to be examined; and a photographing optical system having a photographing diaphragm formed with an opening portion and guiding return light of the illumination light guided through the opening portion of the photographing diaphragm from the fundus through a pupil split to an image sensor, the slit-like opening portion, the two opening portions, and the opening portion of the photographing diaphragm being set in a manner that an overlapping region of a beam region of the illumination light and a beam region of the return light in the eye to be examined is disposed toward the fundus side from a posterior surface of a lens of the eye to be examined.

[0012] In a second aspect of some embodiments, in the first aspect, when a width of an image of the opening portion of the slit in the fundus is denoted as Fd, an interval of images of the two opening portions of the iris diaphragm in the iris is denoted as Id, a size of an image of the opening portion of the photographing diaphragm in the iris is denoted as Sd, a distance of a pupil center of the eye to be examined from the posterior surface of the lens in an optical axis direction of the photographing optical system is denoted as LI, and a distance of the pupil center from the fundus in the optical axis direction is denoted as Lf, the following formula is satisfied:

[0013] (Id - Sd) > (2 x Fd x LI / (Lf - LI)).

[0014] In a third aspect of some embodiments, in the first aspect, the slit-like opening portion is capable of being disposed at a position optically substantially conjugate with the fundus, the opening portion of the photographing diaphragm is capable of being disposed at a position optically substantially conjugate with the iris, and when a width of an image of the opening portion of the slit in the fundus is denoted as Fd, an interval of images of the two opening portions of the iris diaphragm in the iris is denoted as Id, and a size of an image of the opening portion of the photographing diaphragm in the iris is denoted as Sd, the following formula is satisfied: (Id - Sd) > (Fd / 2).

[0015] In a fourth aspect of some embodiments, in any one of the first aspect to the third aspect, the ophthalmic apparatus further sets the width, the interval, and the size in a manner that the overlapping region in the eye is disposed toward the eye to be examined side from an anterior surface of a cornea of the eye to be examined.

[0016] In the fifth aspect of some embodiments, in the first aspect, the slit-shaped opening portion can be disposed at a position optically substantially conjugate with the fundus, and the opening portion of the photographing aperture can be disposed at a position optically substantially conjugate with the iris, when a width of an image of the opening portion of the slit in the fundus is denoted as Fd, an interval of images of the two opening portions of the iris diaphragm in the iris is denoted as Id, a size of an image of the opening portion of the photographing aperture in the iris is denoted as Sd, a distance between a pupil center of the examined eye and a posterior surface of the lens in an optical axis direction of the photographing optical system is denoted as LI, a distance between the pupil center and the fundus in the optical axis direction is denoted as Lf, a distance between an anterior surface of the cornea of the examined eye and the pupil center in the optical axis direction is denoted as La, and the pupil center is denoted as an origin position, the following formula is satisfied when (La-LI) x Lf < (2 x LI-Lf) x La: (2 x Fd x LI / (Lf-LI)) < (Id-Sd) < (2 x Fd), and the following formula is satisfied when (La-LI) x Lf > (2 x LI-Lf) x La: (2 x Fd x La / (Lf+La)) < (Id-Sd) < (2 x Fd).

[0017] In the sixth aspect of some embodiments, in the first aspect, the slit-shaped opening portion can be disposed at a position optically substantially conjugate with the fundus, and the opening portion of the photographing aperture can be disposed at a position optically substantially conjugate with the iris, when a width of an image of the opening portion of the slit in the fundus is denoted as Fd, an interval of images of the two opening portions of the iris diaphragm in the iris is denoted as Id, a size of an image of the opening portion of the photographing aperture in the iris is denoted as Sd, and the pupil center of the examined eye is denoted as an origin position, the following formula is satisfied: (Fd / 2) < (Id-Sd) < (2 x Fd).

[0018] A seventh aspect of some embodiments is an ophthalmic apparatus including: an illumination optical system having a slit formed with a slit-shaped opening portion and an iris diaphragm disposed at a position optically substantially conjugate with an iris of an eye to be examined between a light source and the slit and formed with two opening portions at a position separated from a position of an optical axis, the illumination optical system generating slit-shaped illumination light using light from the light source and guiding the illumination light to a fundus of the eye to be examined; and a photographing optical system having a photographing diaphragm formed with an opening portion and guiding return light of the illumination light guided through the opening portion of the photographing diaphragm from the fundus through a pupil split to an image sensor, the slit-shaped opening portion, the interval of the two opening portions, and the size of the opening portion of the photographing diaphragm being set in a manner that an overlapping region of a beam region of the illumination light and a beam region of the return light in the eye to be examined is disposed toward the eye to be examined side from a corneal anterior surface of the eye to be examined.

[0019] In an eighth aspect of some embodiments, in the seventh aspect, the slit-shaped opening portion can be disposed at a position optically substantially conjugate with the fundus, the opening portion of the photographing diaphragm can be disposed at a position optically substantially conjugate with the iris, when a width of an image of the opening portion of the slit in the fundus is denoted as Fd, an interval of images of the two opening portions of the iris diaphragm in the iris is denoted as Id, a size of an image of the opening portion of the photographing diaphragm in the iris is denoted as Sd, a distance of a pupil center of the eye to be examined from the fundus in an optical axis direction of the photographing optical system is denoted as Lf, a distance of the corneal anterior surface from the pupil center in the optical axis direction is denoted as La, and the pupil center is denoted as an origin position, the following formula is satisfied: (2 x Fd x La / (Lf + La)) < (Id - Sd) < (2 x Fd).

[0020] In a ninth aspect of some embodiments, in the seventh aspect, the slit-shaped opening portion can be disposed at a position optically substantially conjugate with the fundus, the opening portion of the photographing diaphragm can be disposed at a position optically substantially conjugate with the iris, when a width of an image of the opening portion of the slit in the fundus is denoted as Fd, an interval of images of the two opening portions of the iris diaphragm in the iris is denoted as Id, a size of an image of the opening portion of the photographing diaphragm in the iris is denoted as Sd, and the pupil center of the eye to be examined is denoted as an origin position, the following formula is satisfied: (18 x Fd / 59) < (Id - Sd) < (2 x Fd).

[0021] In a tenth aspect of some embodiments, in any of the first aspect to the ninth aspect, the size of the slit-shaped opening portion can be changed.

[0022] In a twelfth aspect of the embodiments, in any of the first aspect to the eleventh aspect, a size of the opening portion of the photographing aperture can be changed.

[0023] In a twelfth aspect of the embodiments, in any of the first aspect to the eleventh aspect, a size of the opening portion of the photographing aperture can be changed.

[0024] In a thirteenth aspect of the embodiments, in any of the first aspect to the twelfth aspect, the photographing aperture is a pinhole mirror configured to couple an optical path of the illumination optical system with an optical path of the photographing optical system disposed in a direction of an optical axis passing through the opening portion of the photographing aperture, and to guide the illumination light reflected in a peripheral region of the opening portion of the photographing aperture to the fundus.

[0025] In a fourteenth aspect of the embodiments, in any of the first aspect to the thirteenth aspect, the image sensor is configured to acquire, in a rolling shutter manner, a light-receiving result of the return light of the illumination light corresponding to an irradiation position of the illumination light in the fundus.

[0026] In a fifteenth aspect of the embodiments, in any of the first aspect to the fourteenth aspect, the image sensor is a CMOS image sensor.

[0027] Further, structures involved in the above-described aspects can be arbitrarily combined.

[0028] According to the present application, it is possible to provide a new technique capable of acquiring a high-quality image of an eye to be examined with a simple structure. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 is a schematic view showing a structure example of an optical system of an ophthalmic apparatus involved in the embodiments.

[0030] Figure 2 is a schematic view showing a structure example of a control system of an ophthalmic apparatus involved in the embodiments.

[0031] Figure 3A is a schematic view showing a structure example of an optical system of an ophthalmic apparatus involved in the embodiments.

[0032] Figure 3B is a schematic view showing a structure example of an optical system of an ophthalmic apparatus involved in the embodiments.

[0033] Figure 4 is a working explanatory view of an ophthalmic apparatus involved in the embodiments.

[0034] Figure 5 is a working explanatory view of an ophthalmic apparatus according to an embodiment.

[0035] Figure 6 is a working explanatory view of an ophthalmic apparatus according to an embodiment.

[0036] Figure 7 is a working explanatory view of an ophthalmic apparatus according to an embodiment.

[0037] Figure 8 is a working explanatory view of an ophthalmic apparatus according to an embodiment.

[0038] Figure 9 is a working explanatory view of an ophthalmic apparatus according to an embodiment.

[0039] Figure 10A is a schematic view showing a structure example of an optical system of an ophthalmic apparatus according to a first modification of the embodiment.

[0040] Figure 10B is a schematic view showing a structure example of an optical system of an ophthalmic apparatus according to a second modification of the embodiment.

[0041] Figure 11A is a schematic view showing a structure example of an optical system of an ophthalmic apparatus according to a third modification of the embodiment.

[0042] Figure 11B is a schematic view showing a structure example of an optical system of an ophthalmic apparatus according to a fourth modification of the embodiment.

[0043] Figure 12 is a schematic view showing a structure example of a control system of an ophthalmic apparatus according to the first to fourth modifications of the embodiment.

[0044] Figure 13 is a schematic view showing a structure example of an optical system of an ophthalmic apparatus according to a fifth modification of the embodiment.

[0045] Figure 14 is a schematic view showing a structure example of an optical system of an ophthalmic apparatus according to a fifth modification of the embodiment.

[0046] Figure 15 is a schematic view showing a structure example of an optical system of an ophthalmic apparatus according to a sixth modification of the embodiment.

[0047] Figure 16 is a schematic view showing a structure example of an optical system of an ophthalmic apparatus according to a sixth modification of the embodiment. DETAILED DESCRIPTION

[0048] An example of an embodiment of an ophthalmic apparatus according to the present application is described in detail with reference to the drawings. Furthermore, the contents of the documents described in this specification can be appropriately cited as the contents of the following embodiments.

[0049] The ophthalmic apparatus according to the embodiment illuminates a predetermined portion of an eye to be examined while moving the position of irradiation (illumination region, irradiation range) of slit-shaped illumination light, and receives return light from the predetermined portion using an image sensor in which light-receiving elements are arranged in one or two dimensions. The light-receiving result of the return light is read from the light-receiving element at the light-receiving position corresponding to the position of irradiation of the illumination light in synchronization with the timing of the movement of the position of irradiation of the illumination light. In some embodiments, the predetermined portion is the anterior eye segment or the posterior eye segment. The anterior eye segment includes the cornea, the iris, the lens, the ciliary body, the zonule of Zinn, and the like. The posterior eye segment includes the vitreous body, the fundus, or the vicinity thereof (the retina, the choroid, the sclera, and the like), and the like.

[0050] The control method of the ophthalmic apparatus according to the embodiment includes one or more steps for realizing the processing performed by the processor (computer) in the ophthalmic apparatus according to the embodiment. The program according to the embodiment causes the processor to perform each step of the control method of the ophthalmic apparatus according to the embodiment.

[0051] In this specification, a "processor" refers to, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), a programmable logic device (for example, a SPLD (Simple Programmable Logic Device), a CPLD (Complex Programmable Logic Device), an FPGA (Field Programmable Gate Array), or the like), or the like. The processor realizes the functions according to the embodiments, for example, by reading and executing a program stored in a storage circuit or a storage device.

[0052] Hereinafter, a case in which the ophthalmic apparatus according to the embodiment acquires an image of the fundus of an eye to be examined is mainly described.

[0053] [Structure of optical system]

[0054] Figure 1 、 Figure 2 、 Figure 3A and Figure 3B A schematic view showing an example of the structure of the ophthalmic apparatus according to the embodiment is shown.Figure 1 A configuration example of an optical system of an ophthalmic apparatus 1 to which the embodiment is applied is shown. Figure 2 A block diagram showing a configuration example of a control system (processing system) of the ophthalmic apparatus 1 to which the embodiment is applied is shown. Figure 3A A first configuration example of the iris diaphragm 21 is schematically shown as viewed in the direction of the optical axis O. Figure 1 A second configuration example of the iris diaphragm 21 is schematically shown as viewed in the direction of the optical axis O. Figure 3B A second configuration example of the iris diaphragm 21 is schematically shown as viewed in the direction of the optical axis O. Figure 1 A second configuration example of the iris diaphragm 21 is schematically shown as viewed in the direction of the optical axis O. Figures 1-3B In the following description, the same reference numerals are attached to the same parts, and the description is appropriately omitted.

[0055] The ophthalmic apparatus 1 includes a light source 10, an illumination optical system 20, a light scanner 30, a projection optical system 35, a photographing optical system 40, and an image pickup device 50. In some embodiments, the illumination optical system 20 includes at least one of the light source 10, the light scanner 30, and the projection optical system 35. In some embodiments, the photographing optical system 40 includes the image pickup device 50. In some embodiments, the projection optical system 35 or the photographing optical system 40 includes the light scanner 30.

[0056] (light source 10)

[0057] The light source 10 includes a visible light source that generates light in the visible region. For example, the light source 10 generates light having a central wavelength in the wavelength range of 420 nm to 700 nm. Such a light source 10 includes, for example, an LED (Light Emitting Diode), an LD (Laser Diode), a halogen lamp, or a xenon lamp. In some embodiments, the light source 10 includes a white light source or a light source capable of outputting light of each color component of RGB. In some embodiments, the light source 10 includes a light source capable of switching and outputting light in the infrared region or light in the visible region. The light source 10 is disposed at a position optically non-conjugate to the fundus Ef and the iris, respectively.

[0058] (illumination optical system 20)

[0059] The illumination optical system 20 generates slit-shaped illumination light using light from the light source 10. The illumination optical system 20 guides the generated illumination light to the light scanner 30.

[0060] The illumination optical system 20 includes an iris diaphragm 21, a slit 22, and a relay lens 23. Light from the light source 10 passes through an opening portion formed in the iris diaphragm 21, passes through an opening portion formed in the slit 22, and passes through the relay lens 23. The relay lens 23 includes one or more lenses. Light that has passed through the relay lens 23 is guided to the light scanner 30.

[0061] (Iris diaphragm 21)

[0062] The iris diaphragm 21 (specifically, an opening portion described later) can be disposed at a position optically substantially conjugate with the iris (pupil) of the subject eye E. One or more opening portions are formed in the iris diaphragm 21 at positions separated from the optical axis O.

[0063] For example, Figure 3A As shown, the opening portions 21A, 21B having a predetermined thickness are formed in the iris diaphragm 21 along a circumferential direction centered on the optical axis O. The interval Id of the opening portions 21A, 21B is an interval in a direction passing through the optical axis position.

[0064] For example, Figure 3B As shown, the opening portions 21A, 21B having a predetermined thickness are formed in the iris diaphragm 21 along a circumferential direction centered on the optical axis O. The interval Id of the opening portions 21A, 21B is an interval in a direction passing through the optical axis position.

[0065] The opening portions formed in the iris diaphragm 21 define the incident position (incident shape) of the illumination light in the iris of the subject eye E. For example, Figure 3A or Figure 3B As shown, by forming the opening portions 21A, 21B, it is possible to cause the illumination light to be incident into the eye from a position eccentric from the pupil center (specifically, a position point-symmetric with the pupil center) when the pupil center of the subject eye E is disposed at the optical axis O.

[0066] The shape of the opening portions formed in the iris diaphragm 21 is not limited to Figure 3A the circular arc shape shown or Figure 3B the arc shape shown. In some embodiments, the shape of each of the opening portions 21A, 21B is a rectangular shape. In some embodiments, the shape of each of the opening portions 21A, 21B is an elliptical shape.

[0067] In addition, by changing the relative position between the light source 10 and the opening portions formed in the iris diaphragm 21, it is possible to change the light amount distribution of the light passing through the opening portions formed in the iris diaphragm 21.

[0068] (Slit 22)

[0069] The slit 22 (specifically, an opening portion described later) can be disposed at a position optically substantially conjugate with the fundus Ef of the subject eye E. For example, an opening portion is formed in the slit 22 in a direction corresponding to the line direction (row direction) in which the image sensor 51 described later reads in a rolling shutter manner. The opening portion formed in the slit 22 defines the irradiation pattern of the illumination light in the fundus Ef of the subject eye E.

[0070] The slit 22 is movable in the optical axis direction of the illumination optical system 20 by a driving mechanism (driving mechanism 22D described later). The driving mechanism moves the slit 22 in the optical axis direction under the control of a control section 100 described later. For example, the control section 100 controls the driving mechanism in accordance with the state of the eye E under examination. Thereby, the position of the slit 22 can be moved in accordance with the state of the eye E under examination (specifically, the refractive power, the shape of the fundus Ef).

[0071] In some embodiments, the slit 22 is configured to be able to change at least one of the position and the shape of the opening portion in accordance with the state of the eye E under examination without moving in the optical axis direction. The function of such a slit 22 is realized, for example, by a liquid crystal shutter.

[0072] The light from the light source 10 that has passed through the opening portion of the iris diaphragm 21 passes through the opening portion formed in the slit 22, and thereby is output as slit-shaped illumination light. The slit-shaped illumination light is transmitted through the relay lens 23 and guided to the light scanner 30.

[0073] (Light scanner 30)

[0074] The light scanner 30 is disposed at a position optically substantially conjugate with the iris of the eye E under examination. The light scanner 30 deflects the slit-shaped illumination light that has transmitted through the relay lens 23 (the slit-shaped light that has passed through the opening portion formed in the slit 22). Specifically, the light scanner 30 deflects the slit-shaped illumination light for a predetermined illumination range for sequentially illuminating the fundus Ef while changing the deflection angle within a predetermined deflection angle range with the iris of the eye E under examination or the vicinity thereof as the scan center position, and guides it to the projection optical system 35. The light scanner 30 can one-dimensionally or two-dimensionally deflect the illumination light.

[0075] When one-dimensionally deflecting, the light scanner 30 includes a galvanometer scanner that deflects the illumination light within a predetermined deflection angle range with reference to a predetermined deflection direction. When two-dimensionally deflecting, the light scanner 30 includes a first galvanometer scanner and a second galvanometer scanner. The first galvanometer scanner deflects the illumination light in such a manner that the irradiation position of the illumination light moves in a horizontal direction orthogonal to the optical axis of the illumination optical system 20. The second galvanometer scanner deflects the illumination light deflected by the first galvanometer scanner in such a manner that the irradiation position of the illumination light moves in a vertical direction orthogonal to the optical axis of the illumination optical system 20. The scan method of moving the irradiation position of the illumination light by the light scanner 30 includes, for example, horizontal scanning, vertical scanning, cross scanning, radial scanning, circular scanning, concentric circular scanning, spiral scanning, and the like.

[0076] (Projecting optical system 35)

[0077] The projection optical system 35 guides the illumination light deflected by the light scanner 30 to the fundus Ef of the eye E. In an embodiment, the projection optical system 35 guides the illumination light deflected by the light scanner 30 to the fundus Ef via an optical path after coupling with the optical path of the photographing optical system 40 through the aperture mirror 45 which is an optical path coupling member described later.

[0078] The projection optical system 35 includes a relay lens 41, a black dot plate 42, a mirror 43, and a relay lens 44. Each of the relay lenses 41, 44 includes one or more lenses.

[0079] (The black dot plate 42)

[0080] The black dot plate 42 is disposed at a position optically substantially conjugate with a lens surface of the objective lens 46 or in the vicinity thereof. Thereby, it is possible to prevent the reflected light from the lens surface of the objective lens 46 from being guided to the imaging device 50.

[0081] In this projection optical system 35, the illumination light deflected by the light scanner 30 transmits through the relay lens 41, passes through the black dot plate 42, and is reflected toward the aperture mirror 45 by the mirror 43.

[0082] (The photographing optical system 40)

[0083] The photographing optical system 40 guides the illumination light guided by the projection optical system 35 to the fundus Ef of the eye E, and guides the return light of the illumination light from the fundus Ef to the imaging device 50.

[0084] In the photographing optical system 40, the optical path of the illumination light from the projection optical system 35 and the optical path of the return light of the illumination light from the fundus Ef are coupled. By using the aperture mirror 45 as an optical path coupling member which couples these optical paths, it is possible to make the illumination light and the return light thereof pupil-divided.

[0085] The photographing optical system 40 includes the aperture mirror 45, an objective lens 46, a focus lens 47, a relay lens 48, and an imaging lens 49. Each of the relay lenses 48 includes one or more lenses.

[0086] (The aperture mirror 45)

[0087] In the aperture mirror 45, a hole portion is formed which is disposed on the optical axis of the photographing optical system 40. The hole portion of the aperture mirror 45 is disposed at a position optically substantially conjugate with the iris of the eye E. The aperture mirror 45 reflects the illumination light from the projection optical system 35 toward the objective lens 46 in a peripheral region of the hole portion. This aperture mirror 45 functions as a photographing stop.

[0088] That is, the pinhole mirror 45 is configured to couple the optical path of the illumination optical system 20 (the projection optical system 35) with the optical path of the photographing optical system 40 disposed in the direction of the optical axis passing through the hole portion, and to guide the illumination light reflected in the peripheral region of the hole portion to the fundus Ef.

[0089] (Focusing lens 47)

[0090] The focusing lens 47 is movable in the optical axis direction of the photographing optical system 40 by a movement mechanism not shown. The movement mechanism moves the focusing lens 47 in the optical axis direction under the control from a control section 100 described later. Thereby, depending on the state of the subject eye E, the return light of the illumination light passing through the hole portion of the pinhole mirror 45 can be imaged on the light receiving surface of the image sensor 51 of the image pickup device 50.

[0091] In this photographing optical system 40, the illumination light from the projection optical system 35 is reflected in the peripheral region of the hole portion formed in the pinhole mirror 45 toward the objective lens 46. The illumination light reflected in the peripheral region of the pinhole mirror 45 is refracted by the objective lens 46, thereby being incident into the eye through the pupil of the subject eye E, and illuminating the fundus Ef of the subject eye E.

[0092] The return light of the illumination light from the fundus Ef is refracted by the objective lens 46, and passes through the hole portion of the pinhole mirror 45, the focusing lens 47, the relay lens 48, and is imaged on the light receiving surface of the image sensor 51 of the image pickup device 50 by the imaging lens 49.

[0093] (Image pickup device 50)

[0094] The image pickup device 50 includes an image sensor 51 that receives the return light of the illumination light guided from the fundus Ef of the subject eye E through the photographing optical system 40. The image pickup device 50 can output the light receiving result of the return light under the control from the control section 100 described later.

[0095] (Image sensor 51)

[0096] The image sensor 51 realizes the function as a pixelated light receiver. The light receiving surface (detection surface, image pickup surface) of the image sensor 51 can be disposed at a position optically substantially conjugate with the fundus Ef.

[0097] The light receiving result based on the image sensor 51 is acquired and read by a rolling shutter method. In some embodiments, the control section 100 described later controls the reading of the light receiving result by controlling the image sensor 51. In some embodiments, the image sensor 51 can automatically output the light receiving result of a predetermined line equivalent with information indicating the light receiving position.

[0098] This image sensor 51 includes a CMOS image sensor. In this case, the multiple pixel (light-receiving element) groups arranged in the row direction of the image sensor 51 include multiple pixels arranged in the column direction. Specifically, the image sensor 51 includes multiple pixels arranged in two dimensions, multiple vertical signal lines, and horizontal signal lines. Each pixel includes a photodiode (light-receiving element) and a capacitor. Multiple vertical signal lines are provided in each pixel group in the column direction (vertical direction) orthogonal to the row direction (horizontal direction). Each vertical signal line is selectively electrically connected to a pixel group that has accumulated a charge corresponding to the light-receiving result. The horizontal signal lines are selectively electrically connected to the multiple vertical signal lines. Each pixel accumulates a charge corresponding to the light-receiving result of the returned light, and the accumulated charge is read sequentially, for example, in each pixel group in the row direction. For example, a voltage corresponding to the charge accumulated in each pixel is provided to the vertical signal lines for each row in the row direction. The multiple vertical signal lines are selectively electrically connected to the horizontal signal lines. By sequentially performing the reading operation in each row direction in the vertical direction, the light-receiving result of the multiple pixels arranged in two dimensions can be read.

[0099] This image sensor 51 acquires (reads) the received light using a rolling shutter method, thereby obtaining a received image corresponding to the desired virtual opening shape extending in the row direction. Such control is disclosed, for example, in U.S. Patent No. 8,237,835.

[0100] Figure 4 A diagram illustrating the operation of the ophthalmic device 1 according to the embodiment is shown. Figure 4 The diagram schematically illustrates the illumination range IP of the slit-shaped illumination light illuminating the fundus Ef and the virtual opening range OP in the light-receiving surface SR of the image sensor 51.

[0101] For example, the control unit 100, described later, uses the light scanner 30 to deflect the slit-shaped illumination light formed by the illumination optics system 20. As a result, in the fundus Ef, the illumination range IP of the slit-shaped illumination light moves (displaces) sequentially in a direction orthogonal to the slit direction (e.g., the row direction, the horizontal direction) in a direction (e.g., the vertical direction).

[0102] In the light-receiving surface SR of the image sensor 51, for example, the control unit 100 (described later) changes the number of pixels of the acquired object in row units, thereby setting a virtual aperture range (aperture region) OP. Ideally, the aperture range OP should be the light-receiving range IP' of the illumination light returning from the light-receiving surface SR, or a range wider than the light-receiving range IP'. For example, the control unit 100 (described later) performs movement control of the aperture range OP synchronously with the movement control of the illumination range IP. Therefore, it is not affected by unwanted scattered light, and a high-quality image of the fundus Ef with strong contrast can be obtained with a simple structure.

[0103] Figure 5 and Figure 6 An example of control timing of a rolling shutter method for the image sensor 51 is schematically shown. Figure 5 An example of timing of read control for the image sensor 51 is shown. Figure 6 is a graph in which a moving control timing of an irradiation range IP (light receiving range IP') of the illumination light is superimposed on the read control timing of the Figure 5 Figure 5 and Figure 6 In the

[0104] Further, in the Figure 5 and Figure 6 In the Figure 6 , for the sake of explanation, a slit width (width in the row direction) of the slit-shaped illumination light is set to 40 rows.

[0105] The read control in the row direction includes reset control, exposure control, charge transfer control, and output control. The reset control is control to initialize the accumulation amount of the charge accumulated in the pixel in the row direction. The exposure control is control to irradiate the photodiode with light and accumulate the charge corresponding to the light receiving amount in the capacitor. The charge transfer control is control to transfer the amount of charge accumulated in the pixel to the vertical signal line. The output control is control to output the amount of charge accumulated in the plurality of vertical signal lines via the horizontal signal line. That is, as shown in Figure 7 , the read time T of the amount of charge accumulated in the pixel in the row direction is the sum of the time Tr required for the reset control, the time Te required for the exposure control (exposure time), the time Tc required for the charge transfer control, and the time Tout required for the output control.

[0106] In the Figure 5 , the read (acquisition) start timing (start timing of the time Tc) is shifted in units of rows, whereby the light receiving result (amount of charge) in the pixel accumulated in the desired range in the image sensor 51 is acquired. For example, when the pixel range shown in Figure 7 is an image corresponding to one frame, the frame rate FR is uniquely determined.

[0107] ​In the present embodiment, the irradiation position of the illumination light having a plurality of line-number-equivalent slit widths in the fundus Ef is sequentially shifted in the direction corresponding to the column direction in the fundus Ef. When the width in the direction of the shift of the irradiation range IP' (a region corresponding to the illumination region in the fundus Ef) in the light-receiving surface of the image sensor 51 has two or more line-number-equivalent widths, the control section 100 described later controls so as to control the light scanner 30 in a manner that the opening range OP (opening region) is shifted in the direction of the shift by a predetermined line-number unit.

[0108] For example, as shown in FIG. 6, the irradiation position of the illumination light in the fundus Ef is shifted in the direction corresponding to the column direction in line units every predetermined shift time Δt. The shift time Δt is obtained by dividing the exposure time Te of the pixel in the image sensor 51 by the slit width of the illumination light (for example, the number of lines of the slit width = 40) (Δt = Te / 40). In synchronization with the moving timing of the irradiation position, the reading start timing of each of the lines of the pixels is delayed to start in shift time Δt units per line. Thereby, a high-quality image of the fundus Ef with strong contrast can be obtained in a short time with simple control. Figure 6

[0109] In some embodiments, the image sensor 51 is constituted by one or more line sensors.

[0110] [Structure of Control System]

[0111] As shown in FIG. 7, the control system of the ophthalmic apparatus 1 is constituted with the control section 100 at the center. Further, at least a part of the structure of the control system can also be included in the ophthalmic apparatus 1. Figure 2 (Control Section 100)

[0112] The control section 100 controls each section of the ophthalmic apparatus 1. The control section 100 includes a main control section 101 and a storage section 102. The main control section 101 includes a processor, and performs processing according to a program stored in the storage section 102, thereby performing control processing of each section of the ophthalmic apparatus 1.

[0113] (Main Control Section 101)

[0114] The main control section 101 performs control of the light source 10, control of the moving mechanism 10D, control of the illumination optical system 20, control of the light scanner 30, control of the photographing optical system 40, control of the image pickup device 50, and control of the data processing section 200.

[0115] The control of the light source 10 includes switching of the light source on, off (or wavelength region of light), and change control of the light amount of the light source.

[0116]

[0117] ​​The moving mechanism 10D changes at least one of the position and orientation of the light source 10 using a known mechanism. The main control unit 101 is capable of changing at least one of the relative position and relative orientation of the light source 10 with respect to the iris aperture 21 and the slit 22.

[0118] The control of the illumination optical system 20 includes the control of the drive mechanism 22D. The drive mechanism 22D moves the slit 22 along the optical axis of the illumination optical system 20. The main control unit 101 controls the drive mechanism 22D according to the state of the examined eye E, thereby positioning the slit 22 at a position corresponding to the state of the examined eye E. The state of the examined eye E includes the shape of the fundus Ef, refractive power, axial length, etc. The refractive power can be obtained by a known eye refractive power measuring device, such as those disclosed in Japanese Patent Application Publication No. 61-293430 or Japanese Patent Application Publication No. 2010-259495. The axial length can be obtained by a known axial length measuring device or by measurement using an optical coherence tomography (OCT).

[0119] For example, first control information, which pre-associates the position of the slit 22 in the optical axis of the illumination optical system 20 with respect to the refractive power, is stored in the storage unit 102. The main control unit 101 refers to the first control information to specify the position of the slit 22 corresponding to the refractive power, and controls the moving mechanism 22D in such a way that the slit 22 is positioned in the specified position.

[0120] Here, as the slit 22 moves, the light distribution through the opening of the slit 22 changes. At this time, as described above, the main control unit 101 can change the position and orientation of the light source 10 by controlling the moving mechanism 10D.

[0121] The control of the optical scanner 30 includes controlling the angle of the deflection surface that deflects the illumination light. By controlling the angle range of the deflection surface, the scanning range (scan start position and scan end position) can be controlled. By controlling the rate at which the angle of the deflection surface changes, the scanning speed can be controlled.

[0122] The control of the imaging optical system 40 includes the control of the moving mechanism 47D. The moving mechanism 47D moves the focusing lens 47 along the optical axis of the imaging optical system 40. The main control unit 101 can control the moving mechanism 47D based on the analysis results of the image obtained using the image sensor 51. In addition, the main control unit 101 can control the moving mechanism 47D based on the operation content of the user using the operation unit 110 described later.

[0123] The control of the imaging device 50 includes the control of the image sensor 51. The control of the image sensor 51 includes control for reading the light-receiving result in a rolling shutter manner (for example, setting of the light-receiving size corresponding to the size of the illumination pattern, and the like). In addition, the control of the image sensor 51 includes reset control, exposure control, charge transfer control, output control, and the like. The time Tr required for the reset control, the time Te required for the exposure control (exposure time), the time Tc required for the charge transfer control, the time Tout required for the output control, and the like can be changed.

[0124] The control of the data processing section 200 includes various image processing, analysis processing with respect to the light-receiving result obtained from the image sensor 51. The image processing includes noise removal processing with respect to the light-receiving result, brightness correction processing for easily recognizing a predetermined site drawn in a light-receiving image based on the light-receiving result. The analysis processing includes specific processing of the focus state, and the like.

[0125] The data processing section 200 can form a light-receiving image corresponding to an arbitrary opening range, based on the light-receiving result read from the image sensor 51 in a rolling shutter manner. The data processing section 200, as an image forming section, can sequentially form light-receiving images corresponding to the opening ranges, and form an image of the eye E from the plurality of formed light-receiving images.

[0126] The data processing section 200 includes a processor, and performs processing in accordance with a program stored in a storage section or the like, thereby realizing the above-described functions.

[0127] In some embodiments, the light source 10 includes two or more light sources. In this case, each of the two or more light sources is provided corresponding to two or more opening portions formed in the iris diaphragm 21. The main control section 101 can change at least one of the position and the orientation (orientation in the direction in which the light amount distribution becomes the largest) of each light source, by controlling the moving mechanism provided corresponding to each of the two or more light sources.

[0128] (Storage section 102)

[0129] The storage section 102 stores various computer programs, data. The computer programs include an arithmetic program for controlling the ophthalmic apparatus 1, a control program.

[0130] (Operation section 110)

[0131] The operation section 110 includes an operation device or an input device. The operation section 110 includes a button, a switch (for example, an operation handle, an operation knob, and the like) provided to the ophthalmic apparatus 1, an operation device (a mouse, a keyboard, and the like). In addition, the operation section 110 can include any operation device, input device such as a trackball, an operation panel, a switch, a button, a dial, and the like.

[0132] (Display section 120)

[0133] The display unit 120 displays an image of the examined eye E generated by the data processing unit 200. The display unit 120 is configured to include a display device such as a flat panel display (LCD). In addition, the display unit 120 may include various display devices such as a touch panel disposed in the housing of the ophthalmic device 1.

[0134] Furthermore, the operation unit 110 and the display unit 120 do not need to be configured as separate devices. For example, a device integrating display and operation functions can be used, such as a touch panel. In this case, the operation unit 110 is configured to include the touch panel and a computer program. Operation content for the operation unit 110 is input to the control unit 100 as an electrical signal. Alternatively, a graphical user interface (GUI) displayed on the display unit 120 can be used for operation and information input with the operation unit 110. In some embodiments, the functions of the display unit 120 and the operation unit 110 are implemented through a touch screen.

[0135] (Other structures)

[0136] In some embodiments, the ophthalmic device 1 also includes a fixation projection system. For example, in Figure 1 In the illustrated optical system structure, the optical path of the fixation projection system is coupled to the optical path of the imaging optical system 40. The fixation projection system can present either an internal fixed target or an external fixed target to the examined eye E. When presenting an internal fixed target to the examined eye E, the fixation projection system includes an LCD that displays the internal fixed target under the control of the control unit 100, and projects the fixation beam output from the LCD onto the fundus of the examined eye E. The LCD is configured to change the display position of the fixed target on its screen. By changing the display position of the fixed target on the LCD, the projection position of the fixed target in the fundus of the examined eye E can be changed. The display position of the fixed target on the LCD can be specified by the user using the operation unit 110.

[0137] In some embodiments, the ophthalmic device 1 includes an alignment system. In some embodiments, the alignment system includes an XY alignment system and a Z alignment system. The XY alignment system is used to align the device optics and the examined eye E in a direction intersecting the optical axis of the device optics (objective lens 46). The Z alignment system is used to align the device optics and the examined eye E in the direction of the optical axis of the ophthalmic device 1 (objective lens 46).

[0138] For example, the XY alignment system projects a bright spot (a bright spot in the infrared or near-infrared region) onto the eye being examined, E. The data processing unit 200 obtains an anterior eye image of the eye being examined, after the bright spot is projected, and calculates the displacement between the bright spot image plotted on the obtained anterior eye image and the alignment reference position. The control unit 100 moves the optical system of the device and the eye being examined relative to each other in a direction intersecting the optical axis via a movement mechanism (not shown) to eliminate the calculated displacement.

[0139] For example, the Z-alignment system projects alignment light in the infrared or near-infrared region from a position offset from the optical axis of the device's optical system and receives the alignment light reflected at the anterior portion of the examined eye E. The data processing unit 200 specifies the distance between the examined eye E and the device's optical system based on the position of the alignment light received, which varies according to the distance between the examined eye E and the device's optical system. The control unit 100 moves the device's optical system and the examined eye E relative to each other in the direction of the optical axis via a movement mechanism (not shown), so that the specified distance becomes the desired working distance.

[0140] In some embodiments, the alignment system functions by using two or more anterior eye cameras positioned at locations offset from the optical axis of the device's optical system. For example, as disclosed in Japanese Patent Application Publication No. 2013-248376, the data processing unit 200 analyzes anterior eye images of the examined eye E acquired substantially simultaneously by two or more anterior eye cameras, using known triangulation to determine the three-dimensional position of the examined eye E. The control unit 100 moves the device's optical system and the examined eye E three-dimensionally relative to each other via a movement mechanism (not shown), such that the optical axis of the device's optical system is substantially aligned with the axis of the examined eye E, and the distance between the device's optical system and the examined eye E becomes a predetermined working distance.

[0141] As described above, in the ophthalmic device 1, the slit 22 (opening), the imaging site (fundus Ef), and the image sensor 51 (light-receiving surface) are arranged in optically conjugate positions. By moving the light-receiving opening in the image sensor 51 in conjunction with the illumination position of the illumination light, the ophthalmic device 1 can suppress the influence of unwanted scattered light while obtaining a clear image of the imaging site.

[0142] In the embodiment, the slit width Fd of the slit 22 formed in the fundus Ef, the interval Id of the images of the opening portions 21A, 21B of the iris diaphragm 21 in the iris, and the size (diameter) Sd of the image of the hole portion of the pinhole 45 formed in the iris are set in a manner that the overlapping region of the beam region of the intraocular illumination light of the examined eye E and the beam region of the return light thereof is configured on the side of the fundus Ef further than the posterior surface of the lens of the examined eye E. Thereby, it is possible to reduce the generation of a flare on the posterior surface of the lens due to the intersection of the beam region of the illumination light and the beam region of the return light in the lens.

[0143] In some embodiments, the slit width Fd, the interval Id of the images of the two opening portions, and the size Sd of the image of the hole portion are set in a manner that the overlapping region of the intraocular of the examined eye E is configured on the side of the examined eye E further than the anterior surface of the cornea of the examined eye E. Thereby, it is possible to reduce the generation of a flare on the anterior surface of the cornea due to the intersection of the beam region of the illumination light and the beam region of the return light between the anterior surface of the cornea and the lens.

[0144] In some embodiments, the slit width Fd, the interval Id, and the size Sd of the hole portion are set in a manner that reduces the generation of a flare on either one of the posterior surface of the lens and the anterior surface of the cornea.

[0145] In the following embodiments, the case where the slit width Fd, the interval Id, and the size Sd of the hole portion are set in a manner that suppresses the generation of a flare on the posterior surface of the lens and the anterior surface of the cornea, respectively, is specifically described.

[0146] First, a coordinate system for defining the beam region of the illumination light and the beam region of the return light thereof is defined. Hereinafter, the return light of the illumination light is sometimes described as a photographing light.

[0147] Further, hereinafter, the distance between the parts is set as a path length (air equivalent distance) without considering the refraction of the eyeball lens. That is, the illumination light and the photographing light (return light) are incident to the intraocular at substantially the same incident angle and substantially the same height, and thus the illumination light and the photographing light are subjected to the same refraction effect. In the case where the refraction effects are the same, the relative relationship of the beam region of the illumination light and the beam region of the photographing light (the position of the intersection point of the illumination light and the photographing light) to the parts in the intraocular such as the cornea, the lens, the fundus, and the like does not cause an influence.

[0148] Figure 7 An example of the coordinate system for defining the beam region passing through the intraocular according to the embodiment is shown. In the coordinate system, the origin O is set on the anterior surface of the cornea of the examined eye E. The X-axis is set in the direction of the optical axis of the examined eye E. The Y-axis is set in the direction of the vertical line of the examined eye E. The Z-axis is set in the direction of the horizontal line of the examined eye E. Figure 7In the diagram, the horizontal axis represents the x-axis, indicating the position of the intraocular portion along the optical axis of the imaging optical system 40 (illumination optical system 20), and the vertical axis represents the y-axis, indicating the intraocular position in a direction orthogonal to the optical axis of the imaging optical system 40 (illumination optical system 20). Furthermore, Figure 7 The origin of the coordinate system is located at the center of the pupil, which is equivalent to the center of the pupil of the examined eye E.

[0149] exist Figure 7 In the coordinate system shown, the distance in the x-direction between the position of the anterior corneal surface (corresponding to the anterior corneal surface) and the position of the pupil center (origin) (corresponding to the pupil center) is represented as La (La>0), the distance in the x-direction between the position of the pupil center and the position of the posterior lens surface (corresponding to the posterior lens surface) is represented as LI (LI>0), and the distance in the x-direction between the position of the pupil center and the fundus is represented as Lf (Lf>0).

[0150] <Suppressing the formation of light spots on the posterior surface of the lens>

[0151] Next, in Figure 7 In the coordinate system defined as shown, in order to determine the boundary of the overlapping area between the illumination beam region and the imaging beam region that causes the spot to form on the posterior surface of the lens, the x-coordinate of the intersection point of the illumination ray and the imaging ray is determined.

[0152] Figure 8 An explanatory diagram showing the overlap between the region of the illumination beam that causes the light spot to form on the posterior surface of the lens and the region of the imaging beam. Figure 8 The diagram schematically illustrates the illumination light and the imaging light in a fully aligned state (where the optical axis of the imaging optical system 40 is aligned with the corneal apex). Figure 8 In the middle, to and Figure 7 Identical parts are labeled with the same reference numerals, and descriptions are omitted where appropriate. Figure 8 In this context, ω represents the shooting angle.

[0153] As described above, the openings 21A and 21B of the iris aperture 21 and the aperture formed in the pore lens 45 are positioned optically approximately conjugate with the iris (i.e., the pupil center) of the examined eye E. Therefore, in Figure 8 In the middle, the spacing Id of the openings 21A and 21B of the iris aperture 21 is defined at the center position of the pupil, and the size (diameter) Sd of the aperture formed in the aperture lens 45 is defined.

[0154] Furthermore, as described above, the slit 22 is positioned optically conjugate to the fundus Ef of the examined eye E. Therefore, in Figure 8 In the middle, the slit width Fd of the slit 22 is defined at the fundus position.

[0155] In this case, the illumination light passes through the opening portions 21A, 21B of the iris diaphragm 21 and reaches the fundus Ef through the opening portion formed in the cleft 22.

[0156] The beam region of this illumination light is demarcated by the illumination light rays SL1, SL2 shown. Specifically, in the y direction, the beam region of the illumination light passing through the opening portion 21A of the iris diaphragm 21 is the region on the upper side than the illumination light ray SL1, and the beam region of the illumination light passing through the opening portion 21B of the iris diaphragm 21 is the region on the lower side than the illumination light ray SL2. Figure 8 Figure 8 In the y direction, the beam region of the illumination light passing through the opening portion 21A of the iris diaphragm 21 is the region on the upper side than the illumination light ray SL1, and the beam region of the illumination light passing through the opening portion 21B of the iris diaphragm 21 is the region on the lower side than the illumination light ray SL2.

[0157] As shown in FIG. 6, the illumination light ray SL1 is represented by a straight line connecting the lower edge of the opening portion 21A of the iris diaphragm 21 in the pupil center position (including the upper edge of the light-shielding region in the position of the optical axis in the iris diaphragm 21) and the lower edge of the opening portion of the cleft 22 in the fundus position. The coordinate position of the lower edge of the opening portion 21A is (0, Id / 2). The coordinate position of the lower edge of the opening portion of the cleft 22 is (Lf, Lf x tan(ω / 2) - Fd / 2). Thus, the illumination light ray SL1 is represented as in Expression (1). Figure 8 [Expression 1]

[0158]

[0159]

[0160] As shown in FIG. 6, the illumination light ray SL1 is represented by a straight line connecting the lower edge of the opening portion 21A of the iris diaphragm 21 in the pupil center position (including the upper edge of the light-shielding region in the position of the optical axis in the iris diaphragm 21) and the lower edge of the opening portion of the cleft 22 in the fundus position. The coordinate position of the lower edge of the opening portion 21A is (0, Id / 2). The coordinate position of the lower edge of the opening portion of the cleft 22 is (Lf, Lf x tan(ω / 2) - Fd / 2). Thus, the illumination light ray SL1 is represented as in Expression (1). Figure 8

[0161] On the other hand, the return light (imaging light) of the illumination light from the fundus Ef is guided to the image sensor 51 from the irradiation position of the illumination light in the fundus Ef through the hole portion formed in the pinhole 45.

[0162] The beam region of this return light of the illumination light is demarcated by the imaging light rays IL1, IL2 shown. Specifically, in the y direction, the beam region of the return light of the illumination light is the region surrounded by the imaging light rays IL1, IL2 (in the range of -Fd / 2 to Fd / 2 in the y direction). Figure 8 Figure 8 In the y direction, the beam region of the return light of the illumination light is the region surrounded by the imaging light rays IL1, IL2 (in the range of -Fd / 2 to Fd / 2 in the y direction). Figure 8 ​​​​In the middle, it is the region that is lower than the shooting light IL1 in the y-direction, and the region that is higher than the shooting light IL2 in the y-direction.

[0163] like Figure 8 As shown, the imaging ray IL1 is represented by a straight line connecting the upper edge of the aperture of the lens 45 at the center of the pupil to the upper edge of the opening of the slit 22 at the fundus. The coordinates of the upper edge of the aperture of the lens 45 are (0, Sd / 2). The coordinates of the upper edge of the opening of the slit 22 are (Lf, Lf×tan(ω / 2)+Fd / 2). Therefore, the imaging ray IL1 is represented as shown in Equation (2).

[0164] [Equation 2]

[0165]

[0166] like Figure 8 As shown, the imaging ray IL2 is represented by a straight line connecting the lower edge of the aperture of the endoscope 45 at the center of the pupil to the lower edge of the opening of the slit 22 at the fundus. The coordinates of the lower edge of the aperture of the endoscope 45 are (0, -Sd / 2). The coordinates of the lower edge of the opening of the slit 22 are (Lf, Lf×tan(ω / 2)-Fd / 2). Therefore, the imaging ray IL2 can be derived in the same way as the imaging ray IL1.

[0167] As described above, when the overlapping area of ​​the illumination beam region and the returning beam region is positioned closer to the fundus Ef side than the posterior surface of the lens, it is possible to suppress the formation of light spots on the posterior surface of the lens. Figure 8 As shown, the position closest to the examined eye E (or objective lens 46) in this overlapping area is the intersection of illumination ray SL1 and imaging ray IL1, or the intersection of illumination ray SL2 and imaging ray IL2. Figure 8 In the diagram, the x-coordinate of the intersection point of illumination ray SL1 and shooting ray IL1 is equal to the x-coordinate of the intersection point of illumination ray SL2 and shooting ray IL2.

[0168] As mentioned above, in Figure 1 In the coordinate system shown, when the x-coordinate of the intersection of the illumination ray SL1 and the imaging ray IL1 is located closer to the fundus Ef side than the position of the posterior surface of the lens, the generation of light spots on the posterior surface of the lens can be completely suppressed. The x-coordinate position Xlens of the intersection is expressed from equations (1) and (2) in a manner independent of the shooting angle ω as in equation (3).

[0169] [Formula 3]

[0170]

[0171] According to formula (3), when Xlens>LI, it is possible to completely suppress the generation of a flare on the posterior surface of the lens. That is, when the slit width Fd, the interval Id, and the size Sd of the hole portion satisfy formula (4), it is possible to completely suppress the generation of a flare on the posterior surface of the lens.

[0172] [Formula 4]

[0173]

[0174] Further, in formula (4), if the pupil diameter Φ that can be photographed defined by the configuration of the ophthalmic apparatus 1 is taken into account, it is necessary to satisfy Id<Φ.

[0175] In some embodiments, in formula (4), the relationship of the slit width Fd, the interval Id, and the size Sd of the hole portion is determined using a parameter representing the configuration of an eyeball. The parameter representing the configuration of an eyeball includes a parameter of a model eye, and the like. The model eye includes a Gullstrand model eye, a Navarro model eye ("Off-axis aberrations of a wide-angle schematic eye model" (I. Escudero-Sanz and R. Navarro, Optical Society of America, August 1999, Vol. 16, No. 8, pp. 1881-1891), and the like. For example, if the position of the anterior surface of the cornea, the position of the posterior surface of the lens, and the position of the fundus with respect to the center position of the pupil are defined using the parameters of the Navarro model eye, La=3.6 [mm], LI=4 [mm], and Lf=20 [mm].

[0176] If LI and Lf derived from the Navarro model eye are used, formula (4) can be expressed as formula (5).

[0177] [Formula 5]

[0178]

[0179] When the slit width Fd, the interval Id, and the size Sd of the hole portion are set in the optical system shown in Figure 7 in a manner that at least formula (4) or formula (5) is satisfied, it is possible to provide an ophthalmic apparatus that can completely suppress the generation of a flare on the posterior surface of the lens.

[0180] <Suppression of generation of flare on anterior surface of cornea>

[0181] Next, in the optical system shown in Figure 9In the coordinate system defined as shown, in order to determine the boundary of the overlapping area between the illumination beam region and the imaging beam region that causes the light spot on the anterior surface of the cornea, the x-coordinate of the intersection point of the illumination ray and the imaging ray is determined.

[0182] Figure 9 An illustrative diagram showing the overlap between the region of the illumination beam that causes the light spot to form a spot and the region of the imaging beam on the anterior surface of the cornea. Figure 8 In the middle, to and Figure 9 Identical parts are labeled with the same reference numerals, and descriptions are omitted where appropriate.

[0183] In this case, the beam area of ​​the illumination light is composed of Figure 9 The illumination rays SL3 and SL4 are shown and delineated. Specifically, in Figure 9 In the iris aperture 21, the beam area of ​​the illumination light passing through the opening 21A of the iris aperture 21 is the area that is higher than the illumination light SL3 in the y direction, and the beam area of ​​the illumination light passing through the opening 21B of the iris aperture 21 is the area that is lower than the illumination light SL4 in the y direction.

[0184] like Figure 9 As shown, the illumination ray SL3 is represented by a straight line connecting the lower edge of the opening 21A of the iris aperture 21 at the center of the pupil (including the upper edge of the light-blocking area at the optical axis position in the iris aperture 21) to the upper edge of the opening of the slit 22 at the fundus position. The coordinate position of the lower edge of the opening 21A is (0, Id / 2). The coordinate position of the upper edge of the opening of the slit 22 is (Lf, Lf×tan(ω / 2)+Fd / 2). Therefore, the illumination ray SL3 is represented as shown in Equation (6).

[0185] [Formula 6]

[0186]

[0187] like Figure 9 As shown, illumination ray SL4 is represented by a straight line connecting the upper edge of the opening 21B of the iris aperture 21 at the center of the pupil (including the lower edge of the light-blocking area at the optical axis position in the iris aperture 21) to the lower edge of the opening of the slit 22 at the fundus position. The coordinates of the lower edge of the opening 21A are (0, -Id / 2). The coordinates of the lower edge of the opening 22 are (Lf, Lf×tan(ω / 2)-Fd / 2). Therefore, illumination ray SL4 can be derived in the same way as illumination ray SL3.

[0188] On the other hand, the beam area of ​​the returning illumination light is composed of Figure 9 The IL3 and IL4 light rays shown are defined. Specifically, in... Figure 9In this case, the light beam region of the return light of the illumination light is a region surrounded by the photographing light rays IL3, IL4.

[0189] As Figure 9 shown, the photographing light ray IL3 is represented by a straight line connecting the upper edge of the hole portion of the hole mirror 45 in the pupil center position and the lower edge of the opening portion of the slit 22 in the fundus position. The coordinate position of the upper edge of the hole portion of the hole mirror 45 is (0, Sd / 2). The coordinate position of the lower edge of the opening portion of the slit 22 is (Lf, Lf x tan(ω / 2) - Fd / 2). Thus, the photographing light ray IL3 is represented as in Expression (7).

[0190] [Expression 7]

[0191]

[0192] As Figure 9 shown, the photographing light ray IL4 is represented by a straight line connecting the lower edge of the hole portion of the hole mirror 45 in the pupil center position and the upper edge of the opening portion of the slit 22 in the fundus position. The coordinate position of the lower edge of the hole portion of the hole mirror 45 is (0, -Sd / 2). The coordinate position of the upper edge of the opening portion of the slit 22 is (Lf, Lf x tan(ω / 2) + Fd / 2). Thus, the photographing light ray IL4 can be derived in the same manner as the photographing light ray IL3.

[0193] As described above, in a case where the overlapping region of the light beam region of the illumination light and the light beam region of the return light thereof is disposed on the side of the examined eye E (the device optical system) from the corneal front surface, it is possible to suppress the generation of a light spot on the corneal front surface. As Figure 9 shown, the position in the overlapping region closest to the fundus Ef is the intersection point of the illumination light ray SL3 and the photographing light ray IL3 or the intersection point of the illumination light ray SL4 and the photographing light ray IL4. In Figure 1 this case, the x-coordinate position of the intersection point of the illumination light ray SL3 and the photographing light ray IL3 is equal to the x-coordinate position of the intersection point of the illumination light ray SL4 and the photographing light ray IL4.

[0194] As described above, in Figure 1 the coordinate system shown, when the x-coordinate position of the intersection point of the illumination light ray SL3 and the photographing light ray IL3 is on the side of the examined eye E from the corneal front surface position, it is possible to completely suppress the generation of a light spot on the corneal front surface. The x-coordinate position Xcor of the intersection point is represented as in Expression (8) from Expressions (6) and (7) in a manner independent of the photographing viewing angle ω.

[0195] [Expression 8]

[0196]

[0197] According to formula (8), when Xcor<-La, it is possible to completely suppress the generation of a flare on the corneal front surface. That is, when the slit width Fd, the interval Id, and the size Sd of the hole portion satisfy formula (9), it is possible to completely suppress the generation of a flare on the corneal front surface.

[0198] [Formula 9]

[0199]

[0200] Further, in formula (9), if the photographable pupil diameter Φ defined by the configuration of the ophthalmic apparatus 1 is taken into account, it is necessary to satisfy Id<Φ.

[0201] Further, in the derivation process of formula (9), the case of (Id-Sd-2xFd)<0 is used. The reason for this is as follows.

[0202] For example, if it is assumed that (Id-Sd-2xFd)>0, on the lens rear surface side, similarly to formula (4), it is necessary to satisfy formula (10) in order to satisfy Xlens>LI.

[0203] [Formula 10]

[0204]

[0205] Further, on the corneal front surface side, similarly to formula (9), it is necessary to satisfy formula (11) in order to satisfy Xcor<-La.

[0206] [Formula 11]

[0207]

[0208] By comparing the right side of formula (10) with the left side of formula (11), when 2xLI<Lf, formula (12) is derived.

[0209] [Formula 12]

[0210]

[0211] Here, from formula (12), the inequality 1<La / (Lf+La) is derived, but this inequality cannot exist.

[0212] Further, by comparing the right side of formula (10) with the left side of formula (11), the inequality 2xLI>Lf is derived, but according to the configuration of the eyeball, this inequality cannot exist either.

[0213] As described above, in the derivation process of formula (9), (Id-Sd-2xFd)<0.

[0214] In some embodiments, in formula (9), a relationship of the slit width Fd, the interval Id, and the size Sd of the aperture is determined using a parameter representing the configuration of the eyeball. The parameter representing the configuration of the eyeball includes a parameter of a model eye and the like. The model eye includes a Gullstrand model eye, a Navarro model eye, and the like.

[0215] As described above, if LI and Lf derived from the Navarro model eye are used, formula (9) can be expressed as shown in formula (13).

[0216] [Formula 13]

[0217]

[0218] When the slit width Fd, the interval Id, and the size Sd of the aperture are set in the optical system shown in at least a manner satisfying formula (9) or formula (13), it is possible to provide an ophthalmic apparatus capable of completely suppressing the generation of a spot on the anterior surface of the cornea. Figure 10A

[0219] In some embodiments, the slit width Fd, the interval Id, and the size Sd of the aperture are set in a manner completely suppressing both the generation of a spot on the posterior surface of the lens and the generation of a spot on the anterior surface of the cornea.

[0220] In this case, the slit width Fd, the interval Id, and the size Sd of the aperture are set in a manner satisfying both formula (4) and formula (9).

[0221] Specifically, when (La - LI) x Lf < (2 x LI - Lf) x La, the slit width Fd, the interval Id, and the size Sd of the aperture are set in a manner satisfying formula (14).

[0222] [Formula 14]

[0223]

[0224] Further, in formula (14), if the pupil diameter Φ that can be photographed defined by the configuration of the ophthalmic apparatus 1 is taken into account, it is necessary to satisfy Id < Φ.

[0225] For example, in the case where the parameters of the Navarro model eye are used, formula (14) can be expressed as shown in formula (15).

[0226] [Formula 15]

[0227]

[0228] ​Further, in the formula (15), if a pupil diameter Φ that can be shot is defined by the configuration of the ophthalmic apparatus 1, then it is necessary to satisfy Id < Φ.

[0229] On the other hand, when (La - LI) x Lf > (2 x LI - Lf) x La, the slit width Fd, the interval Id, and the size Sd of the hole portion are set in a manner to satisfy the formula (16).

[0230] [Formula 16]

[0231]

[0232] For example, in a case where the parameters of the Navarro model eye are used, the formula (16) can be expressed as shown in the formula (17).

[0233] [Formula 17]

[0234]

[0235] When the slit width Fd, the interval Id, and the size Sd of the hole portion are set in the optical system shown in at least a manner to satisfy the formula (16) or the formula (17), it is possible to provide an ophthalmic apparatus that can completely suppress the generation of a light spot on the posterior surface of the lens and the generation of a light spot on the anterior surface of the cornea. Figure 10B

[0236] The hole mirror 45 is an example of the "shooting aperture" involved in the embodiments.

[0237] <Modified Examples>

[0238] (First to Fourth Modified Examples)

[0239] In the embodiments, the slit width Fd, the interval Id, and the size Sd of the hole portion are set, for example, in an inspection process or a factory shipment process of the ophthalmic apparatus 1. However, the structure involved in the embodiments is not limited thereto. In the first to fourth modified examples of the embodiments, the slit width Fd, the interval Id, and the size Sd of the hole portion are set in accordance with the eyeball configuration of the examined eye E.

[0240] Hereinafter, the first to fourth modified examples of the embodiments will be described focusing on the points of difference between the embodiments.

[0241] [Structure of Optical System]

[0242] The structure of the optical system of the ophthalmic apparatus involved in the first to fourth modified examples of the embodiments differs from the structure of the optical system of the ophthalmic apparatus 1 involved in the embodiments in the iris diaphragm 21, the slit 22, and the hole mirror 45.

[0243] ​In the first and second modifications of the embodiment, the iris aperture 21 can change the size of the opening shape of the openings 21A and 21B. By changing the size of the opening shape of the openings 21A and 21B, the spacing between the openings 21A and 21B can be changed.

[0244] Figure 10A and Figure 10B Examples of the structure of the iris aperture 21 involved in the first and second modifications of the embodiments are shown. Figure 10A The structure of the iris aperture 21 involved in the first variation of the embodiment is shown. Figure 10B The structure of the iris aperture 21 involved in the second variation of the embodiment is shown. Figure 1 as well as Figure 10A This schematically illustrates the view when viewed from the direction of the optical axis O. Figure 10A Example of the structure of iris aperture 21.

[0245] For example, such as Figure 10A As shown, the iris aperture 21 involved in the first modified example includes a turntable, which is configured to be approximately orthogonal to the rotation axis O', which is approximately parallel to the optical axis O. The turntable is configured to rotate about the rotation axis O'. Multiple iris apertures are arranged on the turntable in a circle around the rotation axis O'. By rotating the turntable about the rotation axis O', the multiple iris apertures (in...) can be... Figure 10B In this configuration, iris apertures 211-213 are selectively positioned on the optical axis O. The turntable can rotate automatically or manually. For example, a drive mechanism (21D) controlled by the control unit 100 can rotate the turntable around the rotation axis O'. Figure 10B In the process, the size of the opening shape increases in the following order: iris aperture 211 with openings 21A1 and 21B1, iris aperture 212 with openings 21A2 and 21B2, and iris aperture 213 with openings 21A3 and 21B3.

[0246] Additionally, for example, such as Figure 11A As shown, the iris aperture 21 involved in the second modification includes: an optical component 21C1, configured to be substantially orthogonal to the optical axis O, and having openings 21A and 21B; and a disc-shaped shielding plate 21C2, configured to be substantially orthogonal to the optical axis O, and whose radius can be varied. A portion of the circumference of the shielding plate 21C2 constitutes the inner diameter of the openings 21A and 21B. A mechanism (not shown) can vary the radius of the shielding plate 21C2. The radius of the shielding plate 21C2 can be varied automatically or manually. For example, a mechanism controlled by the control unit 100 can vary the radius of the shielding plate 21C2. Thus, by changing the size of the inner diameter of the openings 21A and 21B, the size of the opening shape of the openings 21A and 21B of the iris aperture 21 can be changed.

[0247] Further, in Figure 11B , a case where the size of the inner diameter of the opening portions 21A, 21B is changed is described, but the size of the outer diameter of the opening portions 21A, 21B can be changed. In this case, by changing the size of the outer diameter of the opening portions 21A, 21B, the size of the opening shape of the opening portions 21A, 21B of the iris diaphragm 21 can be changed.

[0248] Thus, by reducing the size of the opening shape of at least one of the opening portions 21A, 21B, the amount of light of the illumination light passing through the iris diaphragm 21 can be reduced. By increasing the size of the opening shape of at least one of the opening portions 21A, 21B, the amount of light of the illumination light passing through the iris diaphragm 21 can be increased.

[0249] Further, the slit 22 according to the third and fourth modified examples of the embodiment can change the size of the opening shape of the opening portion.

[0250] Figure 11A and Figure 11B A structure example of the slit 22 according to the third and fourth modified examples of the embodiment is shown. Figure 11A A structure example of the slit 22 according to the third modified example of the embodiment is shown. Figure 11B A structure example of the slit 22 according to the fourth modified example of the embodiment is shown. Figure 1 and Figure 11A A structure example of the slit 22 according to the third and fourth modified examples of the embodiment is shown. Figure 11A A structure example of the slit 22 according to the third and fourth modified examples of the embodiment is shown.

[0251] For example, as shown in Figure 11A , the slit 22 according to the third modified example includes a turntable provided substantially orthogonal to a rotation axis O" which is substantially parallel to the optical axis O. The turntable is provided to be rotatable around the rotation axis O". On the turntable, a plurality of slits are provided on a circumference around the rotation axis O". By rotating the turntable around the rotation axis O", the plurality of slits (in Figure 11B , the slits 221 to 223) can be selectively arranged on the optical axis O. The turntable can be rotated automatically or manually. For example, a driving mechanism (22D) controlled by the control section 100 can rotate the turntable around the rotation axis O". In Figure 12 , the size of the opening shape is larger in order of the slit 221, the slit 222, and the slit 223.

[0252] Further, for example, as shown in Figure 12As shown, the slit 22 involved in the fourth modification example includes the shielding plates 22A, 22B which are provided so as to be slidable in a direction substantially orthogonal to the optical axis O. The shielding plates 22A, 22B are slid in opposite directions to each other in a manner that the slit width is changed linearly symmetrically with respect to the center line of the slit passing through the optical axis O. The shielding plates 22A, 22B are slid by automatic or manual operation. For example, a driving mechanism (22D) causes the shielding plates 22A, 22B to slide. For example, the driving mechanism (22D) controlled by the control section 100 causes the shielding plates 22A, 22B to slide.

[0253] Thus, by reducing the width (size of the opening shape) of the slit 22, the amount of light of the illumination light passing through the slit 22 can be reduced. By increasing the width of the slit 22, the amount of light of the illumination light passing through the slit 22 can be increased.

[0254] Further, the aperture mirror 45 involved in the embodiments or the first to fourth modification examples can change the size of the opening shape of the aperture (opening) by a known mechanism. In some embodiments, a mechanism controlled by the control section 100 changes the size of the opening shape of the aperture of the aperture mirror 45. In some embodiments, the aperture mirror 45 includes a reflecting member in which the aperture is formed in the central region and an aperture member which is disposed inside or in the vicinity of the aperture of the reflecting member, and a mechanism controlled by the control section 100 changes the size of the opening shape of the aperture by driving the aperture member.

[0255] Thus, by reducing the size of the opening shape of the aperture of the aperture mirror 45, the amount of light of the return light of the illumination light passing through the aperture can be reduced. By increasing the size of the opening shape of the aperture of the aperture mirror 45, the amount of light of the return light of the illumination light passing through the aperture can be increased.

[0256] [Structure of Control System]

[0257] Figure 2 A block diagram showing a structure example of the control system (processing system) of the ophthalmic apparatus involved in the first to fourth modification examples of the embodiments is shown. In the first to fourth modification examples of the embodiments, the same parts as those of the ophthalmic apparatus 1 involved in the embodiments are denoted by the same reference numerals, and the description is appropriately omitted. Figure 10A In the first to fourth modification examples of the embodiments, the same parts as those of the ophthalmic apparatus 1 involved in the embodiments are denoted by the same reference numerals, and the description is appropriately omitted. Figure 10B

[0258] The control system of the ophthalmic apparatus involved in the first to fourth modification examples of the embodiments differs from the control system of the ophthalmic apparatus 1 involved in the embodiments in the iris diaphragm 21, the slit 22, and the aperture mirror 45.

[0259] The driving mechanism 21D, for example, causes the rotation of the rotary plate shown or changes the radius of the shielding plate 21C2 shown. The driving mechanism 21D can cause the rotation of the rotary plate or the change of the radius of the shielding plate 21C2 under the control of the control section 100. Figure 10A The driving mechanism 21D, for example, causes the rotation of the rotary plate shown or changes the radius of the shielding plate 21C2 shown. The driving mechanism 21D can cause the rotation of the rotary plate or the change of the radius of the shielding plate 21C2 under the control of the control section 100. Figure 10B The driving mechanism 21D, for example, causes the rotation of the rotary plate shown or changes the radius of the shielding plate 21C2 shown. The driving mechanism 21D can cause the rotation of the rotary plate or the change of the radius of the shielding plate 21C2 under the control of the control section 100. Figure 11A ​The illustrated turntable rotates or changes Figure 11B The illustrated radius of the shield plate 21C2.

[0260] The drive mechanism 22D, in addition to the function of the drive mechanism 22D in the embodiment, for example, also causes Figure 11A The illustrated turntable rotates or causes Figure 11B The illustrated shield plates 22A, 22B slide. The drive mechanism 22D is able to cause Figure 13 The illustrated turntable rotates or causes Figure 13 The illustrated shield plates 22A, 22B slide.

[0261] The drive mechanism 45D changes the size of the opening shape of the aperture portion by driving an aperture member disposed inside or near the aperture portion of the reflecting member that constitutes the hole mirror 45. The drive mechanism 45D is able to drive the aperture member under the control of the control section 100.

[0262] The main control section 101 controls at least one of the drive mechanisms 21D, 22D, 45D in accordance with the eyeball configuration of the examined eye E.

[0263] The eyeball configuration of the examined eye E includes a distance La in the optical axis direction of the optical system between the corneal front surface position and the pupil center position of the examined eye E, a distance LI in the optical axis direction of the optical system between the pupil center position and the lens rear surface position, and a distance Lf in the optical axis direction of the optical system between the pupil center position and the fundus position. At least one of the distances La, LI, Lf can be acquired from the measurement value of a known optical coherence tomograph. The main control section 101 can acquire at least one of the distances La, LI, Lf from an optical coherence tomograph device provided outside the ophthalmic apparatus 1. In some embodiments, the main control section 101 acquires a part of the distances La, LI, Lf from the optical coherence tomograph device and the remaining part from the parameters of the model eye, and controls at least one of the drive mechanisms 21D, 22D, 45D in accordance with the acquired parameters that represent the configuration of the eyeball.

[0264] The main control section 101 controls at least one of the drive mechanisms 21D, 22D, 45D in accordance with the eyeball configuration of the examined eye E in a manner that satisfies Expression (4), Expression (5), Expression (9), Expression (13), Expression (14), Expression (15), Expression (16), or Expression (17).

[0265] For example, control information that associates in advance control contents of at least one of the interval of the opening portions 21A, 21B of the iris diaphragm 21, the slit width of the slit 22, and the size of the opening shape of the hole portion of the pinhole mirror 45 is stored in the storage section 102 in correspondence with each of one or more parameters that represent the eyeball configuration of the eye to be examined. The main control section 101 is able to control at least one of the iris diaphragm 21, the slit 22, and the pinhole mirror 45 in accordance with the eyeball configuration of the eye to be examined E by referring to the control information stored in the storage section 102.

[0266] According to the modification of the embodiment, since the interval of the opening portions 21A, 21B of the iris diaphragm 21, the slit width of the slit 22, and the size of the opening shape of the hole portion of the pinhole mirror 45 are changed in accordance with the eyeball configuration of the eye to be examined E, it is possible to completely suppress the generation of a flare regardless of the eyeball configuration of the eye to be examined.

[0267] (Fifth Modification)

[0268] The structure of the ophthalmologic apparatus according to the embodiment or the modification thereof is not limited to the structure described in the embodiment or the modification thereof. In the fifth modification of the embodiment, the optical system is constituted in accordance with the Badal principle. Thereby, it is possible to fix the size of the slit image in the fundus Ef regardless of the diopter number of the eye to be examined E.

[0269] Hereinafter, the structure of the ophthalmologic apparatus according to the fifth modification of the embodiment will be described focusing on the points of difference from the embodiment.

[0270] Figure 1 The structure example of the ophthalmologic apparatus according to the fifth modification of the embodiment will be described. In the Figure 1 , the same components as those of the Figure 14 will be attached with the same reference numerals, and the description will be appropriately omitted.

[0271] The structure of the ophthalmologic apparatus 1a according to the fifth modification of the embodiment is different from the structure of the ophthalmologic apparatus 1 according to the embodiment shown in Figure 14 in that the illumination optical system 20a is provided instead of the illumination optical system 20.

[0272] The structure of the illumination optical system 20a is different from the structure of the illumination optical system 20 in that the relay lens system RL1 is provided instead of the relay lens 23. That is, the relay lens system RL1 is disposed between the light scanner 30 and the slit 22 like the relay lens 23. The relay lens system RL1, the relay lenses 41, 44, and the objective lens 46 constitute a Badal optical system.

[0273] Figure 14A configuration example of the relay lens system RL1 according to the fifth modification of the embodiment is shown. In To Here, the relay lens system RL1 and the light scanner 30 are shown for convenience of explanation. In addition, in Figure 15 Here, the relay lens system RL1 includes three lenses.

[0274] The relay lens system RL1 includes one or more lenses like the relay lens 23. The back focal point position Fl of the relay lens system RL1 is disposed at a position optically substantially conjugate with the iris of the examined eye E.

[0275] That is, as described above, the light scanner 30 disposed at a position substantially conjugate with the iris of the examined eye E is disposed at the back focal point position Fl of the relay lens system RL1 or in the vicinity thereof. Thus, even in the case where the slit 22 moves in the optical axis direction corresponding to the refractive power of the examined eye E, the size of the slit image (image formed by light passing through the opening portion formed in the slit 22) projected to the fundus Ef does not change regardless of the refractive power of the examined eye E. This means that even if the slit 22 moves in the optical axis direction, Figure 15 the projection magnification of the slit image of the fundus Ef does not change.

[0276] The operation of the ophthalmic apparatus la according to the fifth modification is the same as that of the ophthalmic apparatus 1 according to the embodiment, and thus detailed description is omitted.

[0277] The relay lens system RL1 is an example of the "first relay lens system" according to the embodiment.

[0278] According to the fifth modification, by disposing the light scanner 30 at the back focal point position Fl of the relay lens system RL1 (or in the vicinity thereof), a Petzval optical system is constituted by the relay lens system RL1, the relay lenses 41, 42, and the objective lens 46.

[0279] Thus, regardless of the refractive power of the examined eye E, it is possible to fix the projection visual angle (projection magnification) of the slit image with respect to the visual axis of the examined eye E (long direction and short direction of the slit 22). As a result, regardless of the refractive power of the examined eye E, the size of the slit image does not change, and thus it is possible to fix the deflection operation speed of the light scanner 30, and thus it is possible to simplify the control of the light scanner 30.

[0280] In addition, since the projection visual angle (projection magnification) of the slit image with respect to the visual axis of the examined eye E is fixed regardless of the refractive power of the examined eye E, it is possible to fix the illuminance of the slit image on the fundus Ef regardless of the refractive power of the examined eye E.

[0281] Furthermore, when an image is acquired in an ophthalmic device at a predetermined shooting angle, the projection magnification is fixed as described above, so there is no need to set a margin in the length of the long side of the slit 22 set for acquiring a slit image of a predetermined size.

[0282] (Sixth variation)

[0283] The structure of the ophthalmic device described in the embodiments is not limited to that of the ophthalmic device. In the ophthalmic device described in the sixth variation of the embodiments, in order to improve the degree of freedom in optical design, a relay lens system is arranged between the slit 22 and the iris aperture 21.

[0284] The structure of the ophthalmic device involved in the sixth modification of the embodiment will be described below, focusing on the differences between it and the fifth modification of the embodiment.

[0285] Figure 13 This illustrates a structural example of an ophthalmic device according to a sixth variation of the embodiment. Figure 16 In the middle, to and Figure 16 Identical parts are labeled with the same reference numerals, and descriptions are omitted where appropriate.

[0286] The structure of the ophthalmic device 1b in the sixth modification of the embodiment differs from that of the ophthalmic device 1a in the fourth modification of the embodiment in that an illumination optical system 20b is provided instead of an illumination optical system 20a.

[0287] The structure of the illumination optical system 20b differs from that of the illumination optical system 20a in that it includes a relay lens system RL2. Specifically, the relay lens system RL2 is positioned between the slit 22 and the iris aperture 21.

[0288] Figure 16 This illustrates a structural example of the relay lens system RL2 according to the sixth variation of the embodiment. ​ For ease of explanation, the iris aperture 21, relay lens system RL2, slit 22, relay lens system RL1, and optical scanner 30 are shown. Additionally, in... ​ In the middle, the relay lens system RL2 consists of two lenses.

[0289] Like relay lens system RL1, relay lens system RL2 includes more than one lens. An iris aperture 21 is positioned at or near the front focal position F2 of relay lens system RL2.

[0290] As described above, the iris diaphragm 21 is disposed at the front focal position F2 of the relay lens system RL2 or in the vicinity thereof. That is, the rear focal position Fl of the relay lens system RLl is a position optically substantially conjugate with the iris diaphragm 21, and the iris diaphragm 21 is disposed at the front focal position F2 of the relay lens system RL2. Thus, the projection magnification from the iris diaphragm 21 to the light scanner 30 (disposed at the rear focal position Fl) is determined in accordance with the focal distance fl of the relay lens system RLl and the focal distance f2 of the relay lens system RL2. At this time, the projection magnification is (fl / f2).

[0291] The ophthalmic apparatus needs to form an image of the iris diaphragm 21 on the iris of the examined eye E in a predetermined size. When the projection magnification from the iris of the examined eye E via the objective lens 46 to the light scanner 30 is a known projection magnification, it is sufficient to project an image of the iris diaphragm 21 in a predetermined size on the light scanner 30. At this time, the projection magnification from the iris diaphragm 21 to the light scanner 30 is determined in accordance with the focal distance fl of the relay lens system RLl and the focal distance f2 of the relay lens system RL2. Thus, by changing at least one of the focal distances fl, f2, it is possible to easily form an image of the iris diaphragm 60 on the iris of the examined eye E in a predetermined size. In some embodiments, only the focal distance f2 is changed in a state where the focal distance fl is fixed.

[0292] The focal distance fl is the synthetic focal distance of the relay lens system RLl. In some embodiments, the relay lens system RLl includes a plurality of lenses having different refractive indexes, and the focal distance fl is changed by changing at least one of the lenses constituting the relay lens system RLl. In some embodiments, at least one of the lenses constituting the relay lens system RLl is a lens whose refractive index can be changed. The lens whose focal distance can be changed includes a liquid crystal lens, a liquid lens, an Alvarez lens, and the like. Even in the case where the focal distance fl is changed, the rear focal position of the relay lens system RLl is disposed at a position optically substantially conjugate with the iris of the examined eye E (pupil conjugate position).

[0293] The focal distance f2 is the synthetic focal distance of the relay lens system RL2. In some embodiments, the relay lens system RL2 includes a plurality of lenses having different refractive indexes, and the focal distance f2 is changed by changing at least one of the lenses constituting the relay lens system RL2. In some embodiments, at least one of the lenses constituting the relay lens system RL2 is a lens whose refractive index can be changed. Even in the case where the focal distance f2 is changed, the front focal position of the relay lens system RL2 is disposed at a position optically substantially conjugate with the iris of the examined eye E (pupil conjugate position).

[0294] In addition, in order to capture the fundus Ef, it is desirable that the light source emit light with high luminance. However, the size of the light emitting surface (light emitting area, output beam cross-sectional size) of the light source that can be generally obtained (mass-produced light source) is limited, and it is necessary to project the image of the iris diaphragm 21 onto the light scanner 30 at a projection magnification corresponding to the size of the light emitting surface of the light source.

[0295] According to the sixth modification example, since the projection magnification from the iris diaphragm 21 to the light scanner 30 can be changed by changing at least one of the focal distances fl, f2, it is possible to project the image of the iris diaphragm 21 of an arbitrary size onto the light scanner 30 at a desired size. Thereby, even in the case where the size of the light emitting surface of the light source is different, it is possible to project the image of the iris diaphragm 21 of a desired size onto the light scanner 30 by changing only at least one of the focal distances fl, f2, thereby improving the design freedom of the optical system. In particular, by fixing the focal distance fl and changing only the focal distance f2, it is possible to fix the amount of movement of the slit 22 with respect to the change in the diopter number of the examined eye E (the movement sensitivity of the slit 22 with respect to the change in the diopter number), thereby further improving the design freedom of the optical system.

[0296] The operation of the ophthalmic apparatus lb related to the sixth modification example is the same as that of the ophthalmic apparatus la related to the fifth modification example, and thus detailed description is omitted.

[0297] The relay lens system RL2 is an example of the "second relay lens system" related to the embodiments.

[0298] According to the sixth modification example, it is possible to reduce the effective diameter of one or more lenses constituting the relay lens system RLl.

[0299] The reason for this is that a slit 22 is disposed between the optical scanner 30 and the iris diaphragm 21, and the slit 22 is disposed at a position optically substantially conjugate with the fundus Ef of the eye E under examination. The slit 22 is able to move in the optical axis direction in accordance with the diopter number of the eye E under examination. Here, the projection magnification from the iris diaphragm 21 to the optical scanner 30 is determined in accordance with a first distance between the optical scanner 30 and the relay lens system RL1 and a second distance between the iris diaphragm 60 and the relay lens system RL1, and thus when the first distance is shortened, the second distance also needs to be shortened. However, it is necessary to maintain the conjugate relationship with the iris and the conjugate relationship with the fundus Ef while ensuring the movement space of the slit 22 in the optical axis direction, and thus the first distance becomes longer and the effective diameter of the relay lens system RL1 increases. According to the sixth modification example, even if the first distance is shortened by providing the relay lens system RL2, the relay lens system RL2 can be used to adjust the projection magnification. Thus, the movement space of the slit 22 in the optical axis direction is ensured, and it is possible to shorten the first distance while maintaining the conjugate relationship with the iris and the conjugate relationship with the fundus Ef, and thus it is possible to reduce the effective diameter of the one or more lenses constituting the relay lens system RL1.

[0300] In addition, since it is possible to reduce the effective diameter of the one or more lenses constituting the relay lens system RL1, it is possible to shorten the length of the optical system from the optical scanner 30 to the light source 10.

[0301] (Seventh Modification Example)

[0302] Further, in the sixth modification example, it can be that at least one of the focal distance f1 and the focal distance f2 is able to be changed in accordance with the type of the light source 10. The ophthalmic apparatus according to the seventh modification example of the embodiments can change at least one of the focal distance f1 and the focal distance f2 in accordance with the size of the light emitting surface (light emitting area, output beam cross-sectional size) of the light source 10.

[0303] For example, the relay lens system RL1 changes the focal distance f1 in accordance with the size of the light emitting surface of the light source 10, similarly to the sixth modification example. For example, the relay lens system RL2 changes the focal distance f2 in accordance with the size of the light emitting surface of the light source 10, similarly to the sixth modification example.

[0304] In some embodiments, the main control section 101 controls the relay lens system RL1 (or the lens whose refractive index is able to be changed) in accordance with the size of the light emitting surface of the light source 10 specified by the operation section 110, thereby changing the focal distance f1. In some embodiments, the main control section 101 controls the relay lens system RL2 (or the lens whose refractive index is able to be changed) in accordance with the size of the light emitting surface of the light source 10 specified by the operation section 110, thereby changing the focal distance f2.

[0305] [Effects / Advantages]

[0306] The effects and advantages of the ophthalmic apparatus according to the embodiments will be described.

[0307] An ophthalmic apparatus (1) according to some embodiments includes an illumination optical system (20) and a photographing optical system (40). The illumination optical system has a slit (22) formed with a slit-shaped opening portion and an iris diaphragm (21) disposed at a position optically substantially conjugate with an iris of an eye to be examined (E) between a light source (10) and the slit and formed with two opening portions (21A, 21B) at positions separated from a position of an optical axis, and generates slit-shaped illumination light using light from the light source and guides the illumination light to a fundus (Ef) of the eye to be examined. The photographing optical system has a photographing diaphragm (aperture mirror 45) formed with an opening portion (aperture portion) and guides return light of the illumination light guided through the opening portion of the photographing diaphragm from the fundus through a pupil split to an image sensor (51). The width (Fd) of the slit-shaped opening portion, the interval (Id) of the two opening portions, and the size (Sd) of the opening portion of the photographing diaphragm are set in a manner that an overlapping region of a beam region of the illumination light in the eye to be examined and a beam region of the return light is disposed toward the fundus side from a posterior surface of a lens of the eye to be examined.

[0308] According to this structure, since the width of the slit-shaped opening portion formed in the slit, the interval of the two opening portions formed in the iris diaphragm, and the size of the opening portion of the photographing diaphragm are set in a manner that an overlapping region of a beam region of the illumination light and a beam region of its return light is disposed toward the fundus side from a posterior surface of a lens of the eye to be examined, it is possible to completely suppress the generation of a flare on the posterior surface of the lens. Thus, it is possible to acquire a high-quality image of the eye to be examined with a simple structure.

[0309] In some embodiments, the slit-shaped opening portion can be disposed at a position optically substantially conjugate with the fundus, and the opening portion of the photographing diaphragm can be disposed at a position optically substantially conjugate with the iris, and when a width of an image of the opening portion of the slit in the fundus is denoted as Fd, an interval of images of the two opening portions of the iris diaphragm in the iris is denoted as Id, a size of an image of the opening portion of the photographing diaphragm in the iris is denoted as Sd, a distance of a pupil center of the eye to be examined from the posterior surface of the lens in an optical axis direction of the photographing optical system is denoted as LI, and a distance of the pupil center from the fundus in the optical axis direction is denoted as Lf, the following formula is satisfied: (Id-Sd) > (2xFd x LI / (Lf-LI)).

[0310] According to this structure, since the width of the slit-like opening portion formed in the cleft, the interval of the two opening portions of the iris diaphragm, and the size of the opening portion of the photographing diaphragm can be set in a manner satisfying a simple formula, it is possible to completely suppress the occurrence of a flare on the posterior surface of the lens simply.

[0311] In some embodiments, the slit-like opening portion can be disposed at a position optically substantially conjugate with the fundus, the opening portion of the photographing diaphragm can be disposed at a position optically substantially conjugate with the iris, and when the width of the image of the opening portion of the cleft in the fundus is denoted as Fd, the interval of the images of the two opening portions of the iris diaphragm in the iris is denoted as Id, and the size of the image of the opening portion of the photographing diaphragm in the iris is denoted as Sd, the following formula is satisfied: (Id-Sd)>(Fd / 2).

[0312] According to this structure, when a subject eye having a standard eye configuration is imaged using the parameters of the Navarro model eye, it is possible to completely suppress the occurrence of a flare on the posterior surface of the lens simply.

[0313] In some embodiments, the ophthalmic apparatus further sets the width, the interval, and the size in a manner in which the overlapping region in the eye is disposed closer to the subject eye side than the anterior surface of the cornea of the subject eye.

[0314] According to this structure, since the width of the slit-like opening portion formed in the cleft, the interval of the two opening portions of the iris diaphragm, and the size of the opening portion of the photographing diaphragm are set in a manner in which the overlapping region of the beam area of the illumination light and the beam area of the return light thereof is disposed closer to the subject eye side than the anterior surface of the cornea of the subject eye, it is possible to completely suppress the occurrence of a flare on the posterior surface of the lens and the occurrence of a flare on the anterior surface of the cornea. Thus, it is possible to acquire a higher-quality image of the subject eye with a simple structure.

[0315] In some embodiments, the slit-shaped opening portion can be disposed at a position optically substantially conjugate with the fundus, and the opening portion of the photographic aperture can be disposed at a position optically substantially conjugate with the iris, when the width of the image of the slit-shaped opening portion in the fundus is represented as Fd, the interval of the images of the two opening portions of the iris diaphragm in the iris is represented as Id, the size of the image of the opening portion of the photographic aperture in the iris is represented as Sd, the distance between the pupil center of the subject eye and the posterior surface of the lens in the optical axis direction of the photographic optical system is represented as LI, the distance between the pupil center and the fundus in the optical axis direction is represented as Lf, the distance between the corneal anterior surface of the subject eye and the pupil center in the optical axis direction is represented as La, and the pupil center is represented as the origin position, when (La-LI) x Lf < (2 x LI-Lf) x La, the following formula is satisfied: (2 x Fd x LI / (Lf-LI)) < (Id-Sd) < (2 x Fd), and when (La-LI) x Lf > (2 x LI-Lf) x La, the following formula is satisfied: (2 x Fd x La / (Lf+La)) < (Id-Sd) < (2 x Fd).

[0316] According to this structure, since the width of the slit-shaped opening portion formed in the slit, the interval of the two opening portions of the iris diaphragm, and the size of the opening portion of the photographic aperture are set in a manner satisfying a simple formula, it is possible to completely suppress the generation of a flare on the posterior surface of the lens and the generation of a flare on the corneal anterior surface simply.

[0317] In some embodiments, the slit-shaped opening portion can be disposed at a position optically substantially conjugate with the fundus, and the opening portion of the photographic aperture can be disposed at a position optically substantially conjugate with the iris, when the width of the image of the slit-shaped opening portion in the fundus is represented as Fd, the interval of the images of the two opening portions of the iris diaphragm in the iris is represented as Id, the size of the image of the opening portion of the photographic aperture in the iris is represented as Sd, and the pupil center of the subject eye is represented as the origin position, the following formula is satisfied: (Fd / 2) < (Id-Sd) < (2 x Fd).

[0318] According to this structure, when a subject eye having a standard eye configuration is photographed using the parameters of the Navarro model eye, it is possible to completely suppress the generation of a flare on the posterior surface of the lens and the generation of a flare on the corneal anterior surface simply.

[0319] An ophthalmic apparatus (1) according to some embodiments includes an illumination optical system (20) and a photographing optical system (40). The illumination optical system has a slit (22) formed with a slit-shaped opening portion and an iris diaphragm (21) disposed at a position optically substantially conjugate with an iris of an eye to be examined (E) between a light source (10) and the slit and formed with two opening portions (21A, 21B) at positions separated from a position of an optical axis, generates slit-shaped illumination light using light from the light source, and guides the illumination light to a fundus (Ef) of the eye to be examined. The photographing optical system has a photographing diaphragm (aperture mirror 45) formed with an opening portion (aperture portion) and guides return light of the illumination light guided through the opening portion of the photographing diaphragm from the fundus through a pupil split to an image sensor (51). The width (Fd) of the slit-shaped opening portion, the interval (Id) of the two opening portions, and the size (Sd) of the opening portion of the photographing diaphragm are set in a manner that an overlapping region of a beam region of the illumination light in the eye to be examined and a beam region of the return light is disposed toward the eye to be examined side from a corneal front surface of the eye to be examined.

[0320] According to this structure, since the width of the slit-shaped opening portion formed in the slit, the interval of the two opening portions formed in the iris diaphragm, and the size of the opening portion of the photographing diaphragm are set in a manner that an overlapping region of a beam region of the illumination light and a beam region of its return light is disposed toward the eye to be examined side from a corneal front surface of the eye to be examined, it is possible to completely suppress generation of a flare on the corneal front surface. Thus, it is possible to acquire a high-quality image of the eye to be examined with a simple structure.

[0321] In some embodiments, the slit-shaped opening portion can be disposed at a position optically substantially conjugate with the fundus, the opening portion of the photographing diaphragm can be disposed at a position optically substantially conjugate with the iris, and when a width of an image of the opening portion of the slit in the fundus is denoted as Fd, an interval of images of the two opening portions of the iris diaphragm in the iris is denoted as Id, a size of an image of the opening portion of the photographing diaphragm in the iris is denoted as Sd, a distance of the pupil center of the eye to be examined from the fundus in an optical axis direction of the photographing optical system is denoted as Lf, a distance of the corneal front surface from the pupil center in the optical axis direction is denoted as La, and the pupil center is denoted as an origin position, the following formula is satisfied: (2 x Fd x La / (Lf + La)) < (Id - Sd) < (2 x Fd).

[0322] According to this structure, since the width of the slit-shaped opening portion formed in the slit, the interval of the two opening portions formed in the iris diaphragm, and the size of the opening portion of the photographing diaphragm can be set in a manner that a simple formula is satisfied, it is possible to completely suppress generation of a flare on the corneal front surface simply.

[0323] In some embodiments, the slit-shaped opening portion can be disposed at a position optically substantially conjugate with the fundus, and the opening portion of the photographic aperture can be disposed at a position optically substantially conjugate with the iris, and when the width of the image of the opening portion of the slit in the fundus is represented as Fd, the interval of the images of the two opening portions of the iris diaphragm in the iris is represented as Id, the size of the image of the opening portion of the photographic aperture in the iris is represented as Sd, and the center of the pupil of the examined eye is represented as the origin position, the following formula is satisfied: (18 x Fd / 59) < (Id - Sd) < (2 x Fd).

[0324] According to this structure, when the examined eye having a standard eye configuration is imaged using the parameters of the Navarro model eye, the generation of a spot on the corneal front surface can be simply and completely suppressed.

[0325] In some embodiments, the size of the slit-shaped opening portion can be changed.

[0326] According to this structure, an ophthalmic apparatus can be provided in which the size of the slit-shaped opening portion formed in the slit is changed according to the eyeball configuration of the examined eye, thereby suppressing the generation of a spot on the posterior surface of the lens or the corneal front surface, and a high-quality image of the examined eye can be obtained.

[0327] In some embodiments, the interval of the two opening portions can be changed.

[0328] According to this structure, an ophthalmic apparatus can be provided in which the interval of the two opening portions formed in the iris diaphragm is changed according to the eyeball configuration of the examined eye, thereby suppressing the generation of a spot on the posterior surface of the lens or the corneal front surface, and a high-quality image of the examined eye can be obtained.

[0329] In some embodiments, the size of the opening portion of the photographic aperture can be changed.

[0330] According to this structure, an ophthalmic apparatus can be provided in which the size of the opening portion of the photographic aperture is changed according to the eyeball configuration of the examined eye, thereby suppressing the generation of a spot on the posterior surface of the lens or the corneal front surface, and a high-quality image of the examined eye can be obtained.

[0331] In some embodiments, the photographic aperture is a pinhole mirror (45) configured to couple the optical path of the illumination optical system with the optical path of the photographic optical system disposed in the direction of the optical axis passing through the opening portion of the photographic aperture, and to guide the illumination light reflected in the peripheral region of the opening portion of the photographic aperture to the fundus.

[0332] According to this configuration, since the function of the photographing aperture is realized using the pinhole mirror that couples the optical path of the illumination optical system and the optical path of the photographing optical system, it is possible to simplify the configuration of the optical system and acquire a high-quality image of the examined eye while irradiating the fundus with the illumination light through pupil division.

[0333] In some embodiments, the image sensor is configured to acquire, in a rolling shutter manner, a light-receiving result of the return light of the illumination light corresponding to the irradiation position in the fundus.

[0334] According to this configuration, it is possible to provide an ophthalmic apparatus that acquires a light-receiving result of the return light of the illumination light in a rolling shutter manner, whereby it is possible to suppress the generation of flare and acquire a high-quality image of the examined eye with a simple configuration.

[0335] In some embodiments, the image sensor is a CMOS image sensor.

[0336] According to this configuration, it is possible to suppress the generation of flare and acquire a high-quality image of the examined eye with a simple configuration and at low cost.

[0337] The embodiments described above or modifications thereof are merely one example for implementing the present application. A person who implements the present application can implement any modifications, omissions, additions, and the like within the scope of the present application.

[0338] In the above-described embodiments, the ophthalmic apparatus can have, for example, an axial length measurement function, an intraocular pressure measurement function, an optical coherence tomography (OCT) function, an ultrasonic wave examination function, or any function that can be used in the field of ophthalmology. Further, the axial length measurement function is realized by an optical coherence tomograph or the like. In addition, the axial length measurement function can also be realized by projecting light to the examined eye, adjusting the position of the optical system in the Z direction (an anteroposterior direction) with respect to the examined eye, and detecting the return light from the fundus, thereby measuring the axial length of the examined eye. The intraocular pressure measurement function is realized by a tonometer or the like. The OCT function is realized by an optical coherence tomograph or the like. The ultrasonic wave examination function is realized by an ultrasonic diagnostic apparatus or the like. In addition, the present application can also be applied to an apparatus (a compound machine) having two or more of such functions.

[0339] In some embodiments, a program for causing a computer to execute the control method of the ophthalmic apparatus is provided. Such a program can be stored in any recording medium that is non-transitory and readable by a computer. The recording medium can be an electronic medium using magnetism, light, magneto-optical, semiconductor, or the like. Typically, the recording medium is a magnetic tape, a magnetic disk, an optical disk, a magneto-optical disk, a flash memory, a solid state drive, or the like. In addition, the program can also be transmitted and received through a network such as the Internet or a local area network (LAN).

[0340] (Reference numeral explanation)

[0341] 1: ophthalmic apparatus

[0342] 10: light source

[0343] 20: illumination optical system

[0344] 21: iris diaphragm

[0345] 22: slit

[0346] 23, 41, 44, 48: relay lens

[0347] 30: light scanner

[0348] 35: projection optical system

[0349] 40: imaging optical system

[0350] 42: black dot plate

[0351] 43: mirror

[0352] 45: pinhole mirror

[0353] 46: objective lens

[0354] 47: focusing lens

[0355] 49: imaging lens

[0356] 50: image pickup device

[0357] 51: image sensor

[0358] 100: control section

[0359] 101: main control section

[0360] 102: storage section

[0361] 200: data processing section

[0362] E: eye to be examined

[0363] Ef: fundus

Claims

1. An ophthalmic device, characterized in that, include: An illumination optical system having a slit and an iris aperture, the slit having a slit-shaped opening, the iris aperture being positioned between a light source and the slit at a position approximately optically conjugate to the iris of the eye being examined, and having two openings at a position separated from the optical axis; the illumination optical system using light from the light source to generate slit-shaped illumination light and guiding the illumination light to the fundus of the eye being examined. as well as The imaging optical system has an imaging aperture with an opening, and guides the return light of the illumination light, which is guided from the fundus through the pupil and passes through the opening of the imaging aperture, to the image sensor. The slit-like opening can be positioned in a location that is optically conjugate to the fundus. The aperture opening can be positioned approximately conjugate to the optical position of the iris. When the width of the image of the opening of the slit in the fundus is represented as Fd, the interval between the images of the two openings of the iris aperture in the iris is represented as Id, the size of the image of the opening of the imaging aperture in the iris is represented as Sd, the distance between the pupil center of the examined eye and the posterior surface of the lens in the optical axis direction of the imaging optical system is represented as LI, and the distance between the pupil center and the fundus in the optical axis direction is represented as Lf, the following formula is satisfied: (Id-Sd)>(2×Fd×LI / (Lf-LI)).

2. An ophthalmic device, characterized in that, include: An illumination optical system having a slit and an iris aperture, the slit having a slit-shaped opening, the iris aperture being positioned between a light source and the slit at a position approximately optically conjugate to the iris of the eye being examined, and having two openings at a position separated from the optical axis; the illumination optical system using light from the light source to generate slit-shaped illumination light and guiding the illumination light to the fundus of the eye being examined. as well as The imaging optical system has an imaging aperture with an opening, and guides the return light of the illumination light, which is guided from the fundus through the pupil and passes through the opening of the imaging aperture, to the image sensor. The slit-like opening can be positioned in a location that is optically conjugate to the fundus. The aperture opening can be positioned approximately conjugate to the optical position of the iris. When the width of the image of the opening of the slit in the fundus is represented as Fd, the interval between the images of the two openings of the iris aperture in the iris is represented as Id, and the size of the image of the opening of the iris aperture in the iris is represented as Sd, the following formula is satisfied: (Id-Sd)>(Fd / 2).

3. The ophthalmic device according to claim 1 or 2, characterized in that, The ophthalmic device further sets the width, the spacing, and the size such that the overlapping area of ​​the illumination beam region and the return beam region within the eye being examined is positioned closer to the eye than the anterior corneal surface of the eye being examined.

4. An ophthalmic device, characterized in that, include: An illumination optical system having a slit and an iris aperture, the slit having a slit-shaped opening, the iris aperture being positioned between a light source and the slit at a position approximately optically conjugate to the iris of the eye being examined, and having two openings at a position separated from the optical axis; the illumination optical system using light from the light source to generate slit-shaped illumination light and guiding the illumination light to the fundus of the eye being examined. as well as The imaging optical system has an imaging aperture with an opening, and guides the return light of the illumination light, which is guided from the fundus through the pupil and passes through the opening of the imaging aperture, to the image sensor. The width of the slit-shaped opening, the spacing between the two openings, and the size of the aperture opening are set such that the overlapping area of ​​the illumination light beam region and the return light beam region within the examined eye is positioned closer to the fundus than the posterior surface of the lens of the examined eye. The slit-like opening can be positioned in a location that is optically conjugate to the fundus. The aperture opening can be positioned approximately conjugate to the optical position of the iris. When the width of the image of the opening of the slit in the fundus is represented as Fd, the interval between the images of the two openings of the iris aperture in the iris is represented as Id, the size of the image of the opening of the imaging aperture in the iris is represented as Sd, the distance between the pupil center of the examined eye and the posterior surface of the lens in the optical axis direction of the imaging optical system is represented as L1, the distance between the pupil center and the fundus in the optical axis direction is represented as Lf, the distance between the anterior surface of the cornea of ​​the examined eye and the pupil center in the optical axis direction is represented as La, and the pupil center is represented as the origin position, When (La-LI)×Lf<(2×LI-Lf)×La, the following equation is satisfied: (2×Fd×LI / (Lf-LI))<(Id-Sd)<(2×Fd), When (La-LI)×Lf>(2×LI-Lf)×La, the following equation is satisfied: (2×Fd×La / (Lf+La))<(Id-Sd)<(2×Fd).

5. An ophthalmic device, characterized in that, include: An illumination optical system having a slit and an iris aperture, the slit having a slit-shaped opening, the iris aperture being positioned between a light source and the slit at a position approximately optically conjugate to the iris of the eye being examined, and having two openings at a position separated from the optical axis; the illumination optical system using light from the light source to generate slit-shaped illumination light and guiding the illumination light to the fundus of the eye being examined. as well as The imaging optical system has an imaging aperture with an opening, and guides the return light of the illumination light, which is guided from the fundus through the pupil and passes through the opening of the imaging aperture, to the image sensor. The width of the slit-shaped opening, the spacing between the two openings, and the size of the aperture opening are set such that the overlapping area of ​​the illumination light beam region and the return light beam region within the examined eye is positioned closer to the fundus than the posterior surface of the lens of the examined eye. The slit-like opening can be positioned in a location that is optically conjugate to the fundus. The aperture opening can be positioned approximately conjugate to the optical position of the iris. When the width of the image of the opening of the slit in the fundus is represented as Fd, the interval between the images of the two openings of the iris aperture in the iris is represented as Id, the size of the image of the opening of the iris aperture in the iris is represented as Sd, and the center of the pupil of the examined eye is represented as the origin, the following formula is satisfied: (Fd / 2)<(Id-Sd)<(2×Fd).

6. An ophthalmic device, characterized in that, include: An illumination optical system having a slit and an iris aperture, the slit having a slit-shaped opening, the iris aperture being positioned between a light source and the slit at a position approximately optically conjugate to the iris of the eye being examined, and having two openings at a position separated from the optical axis; the illumination optical system using light from the light source to generate slit-shaped illumination light and guiding the illumination light to the fundus of the eye being examined. as well as The imaging optical system has an imaging aperture with an opening, and guides the return light of the illumination light, which is guided from the fundus through the pupil and passes through the opening of the imaging aperture, to the image sensor. The slit-like opening can be positioned in a location that is optically conjugate to the fundus. The aperture opening can be positioned approximately conjugate to the optical position of the iris. When the width of the image of the opening of the slit in the fundus is represented as Fd, the interval between the images of the two openings of the iris aperture in the iris is represented as Id, the size of the image of the opening of the imaging aperture in the iris is represented as Sd, the distance between the pupil center of the examined eye and the fundus in the optical axis direction of the imaging optical system is represented as Lf, the distance between the anterior surface of the cornea and the pupil center in the optical axis direction is represented as La, and the pupil center is represented as the origin, the following formula is satisfied: (2×Fd×La / (Lf+La))<(Id-Sd)<(2×Fd).

7. An ophthalmic device, characterized in that, include: An illumination optical system having a slit and an iris aperture, the slit having a slit-shaped opening, the iris aperture being positioned between a light source and the slit at a position approximately optically conjugate to the iris of the eye being examined, and having two openings at a position separated from the optical axis; the illumination optical system using light from the light source to generate slit-shaped illumination light and guiding the illumination light to the fundus of the eye being examined. as well as The imaging optical system has an imaging aperture with an opening, and guides the return light of the illumination light, which is guided from the fundus through the pupil and passes through the opening of the imaging aperture, to the image sensor. The slit-like opening can be positioned in a location that is optically conjugate to the fundus. The aperture opening can be positioned approximately conjugate to the optical position of the iris. When the width of the image of the opening of the slit in the fundus is represented as Fd, the interval between the images of the two openings of the iris aperture in the iris is represented as Id, the size of the image of the opening of the iris aperture in the iris is represented as Sd, and the center of the pupil of the examined eye is represented as the origin, the following formula is satisfied: (18×Fd / 59)<(Id-Sd)<(2×Fd).

8. The ophthalmic device according to any one of claims 1, 2, 4 to 7, characterized in that, The size of the slit-like opening can be changed.

9. The ophthalmic device according to any one of claims 1, 2, 4 to 7, characterized in that, The distance between the two openings can be changed.

10. The ophthalmic device according to any one of claims 1, 2, 4 to 7, characterized in that, The size of the opening formed in the shooting aperture can be changed.

11. The ophthalmic device according to any one of claims 1, 2, 4 to 7, characterized in that, The shooting aperture is a lens with an aperture that is configured to couple the optical path of the illumination optical system with the optical path of the shooting optical system located in the direction of the optical axis passing through the opening of the shooting aperture, and to guide the illumination light reflected in the peripheral region of the opening of the shooting aperture to the fundus.

12. The ophthalmic device according to any one of claims 1, 2, 4 to 7, characterized in that, The image sensor is configured to acquire the light reception result of the return light of the illumination light corresponding to the illumination position of the illumination light in the fundus using a rolling shutter method.

13. The ophthalmic device according to any one of claims 1, 2, 4 to 7, characterized in that, The image sensor is a CMOS image sensor.

Images