JP6839902B2 - Ophthalmic microscope - Google Patents

Description

The present invention relates to an ophthalmic microscope. More specifically, the present invention relates to an ophthalmic microscope suitable for binocular vision, in which residual aberration can be corrected and the afterimage aberration of an image observed by the left and right eyes is close to equal on the left and right. More specifically, the present invention relates to an ophthalmic microscope in which the objective lens can be made small in diameter and the OCT optical system can be easily installed.

In the field of ophthalmology, various ophthalmic microscopes are used for magnifying and observing the eye. Examples of such an ophthalmic microscope include a fundus camera, a slit lamp, a surgical microscope, and the like. These ophthalmic microscopes have a binocular optical system that provides binocular parallax that occurs between the left and right eyes for stereoscopic observation of the eye.

A typical conventional ophthalmic microscope is a Galilean stereomicroscope. The technical features of the Galilean stereomicroscope are that it is equipped with an objective lens that allows the optical axes of the left and right observation optical systems to pass through in common, and that the optical axes of the left and right observation optical systems are basically parallel. It is supposed to be. The Galilean stereomicroscope has the advantage that it can be easily combined with other optical systems and optical elements.
On the other hand, in the Galilean telescope, since the objective lens and the imaging optical system are eccentric, the residual aberrations are opposite to each other on the left and right, and it is difficult to reduce the residual aberrations.

The present inventors have previously developed an ophthalmic microscope that employs a Greenough stereomicroscope, which is a method different from the Galilean stereomicroscope (Patent Documents 1 and 2). The Greenough stereomicroscope is a microscope that has two independent observation optical systems on the left and right, and is arranged so that the optical axes of the left and right observation optical systems intersect. The Greenough stereomicroscope does not use a common objective lens, and each of the left and right observation optical systems is equipped with an objective lens.
According to the Greenough type physical microscopic boundary, it is possible to reduce the eccentricity of the objective lens and the coupling optical system, but there is a problem that the mechanism becomes complicated because the two independent observation optical systems are obliquely crossed. ..

By the way, as an inspection device that can be combined with an ophthalmic microscope, there is an OCT (Optical Coherence Tomography) device. The OCT device can be used for acquiring a cross-sectional image or a three-dimensional image of the eye, measuring the size of the eye tissue (retina thickness, etc.), acquiring functional information of the eye (blood flow information, etc.), and the like.

Many devices have been developed in which an OCT device is incorporated into an ophthalmic microscope, and most of them are those in which the optical path of the OCT optical system is transmitted through an objective lens of the Galilean type body microscope (Patent Documents 3 to 7). ..
Further, a method has been developed in which the optical path of the OCT optical system does not pass through the Galilean-type objective lens of the real microscopic boundary (Patent Document 8), but the OCT optical system is provided between the objective lens and the eye to be inspected.

By the way, as a device for observing an eye to be inspected, there is an SLO (Scanning Laser Ophthalmoscope) that irradiates the eye to be inspected with a laser beam and detects the reflected light, but there is also a device in which SLO and OCT are combined. It has been developed (Patent Document 9).

Japanese Unexamined Patent Publication No. 2016-185177 Japanese Unexamined Patent Publication No. 2016-185178 Japanese Unexamined Patent Publication No. 8-66421 Japanese Unexamined Patent Publication No. 2008-264488 Japanese Unexamined Patent Publication No. 2008-268852 Special Table 2010-522055 Japanese Unexamined Patent Publication No. 2008-264490 U.S. Pat. No. 8,366,271 JP 2015-221091

The Galileo stereomicroscope used in the conventional ophthalmic microscope system has the optical axis (O400L) of the observation optical system for the left eye and the observation optical system for the right eye, as schematically shown in FIG. 10 (A). An objective lens (401) through which the optical axis (O400R) is commonly transmitted is provided. The observation optical system for the left and right eyes includes, for example, a variable magnification lens (402), an eyepiece lens (408), and the like. However, as schematically shown in FIG. 10B, the optical axis (A402) of the variable magnification lens and the optical axis (A401) of the objective lens are eccentric by about 10 to 15 mm. Therefore, it is difficult to correct the residual aberration that occurs in the left and right eyes. Further, since the residual aberration occurs on the outer peripheral side of the objective lens (401), as shown schematically in FIG. 10C, when the subject (2) is observed with both eyes, chromatic aberration of magnification and coma are generated. There is a problem that the image for the left eye (V400L) and the image for the right eye (V400R) are generated on opposite sides, and different images must be observed by the left and right eyes. There are two types of Galilean stereomicroscopes, one with a convergence angle of 0 ° and the other with a convergence angle of not 0 °. In either type, it is difficult to reduce the residual aberration by correction. It was.

Further, the Galilean stereomicroscope has a demerit that the degree of freedom in optical design and mechanical design is limited because it is necessary to use a large-diameter objective lens.
For example, as shown in Patent Documents 3 to 7, an ophthalmologic microscope in which an OCT optical system is incorporated in a Galilean telescope has a method in which the optical path of the OCT optical system passes through an objective lens of the Galilean telescope. Therefore, the OCT optical system and the observation optical system could not be made independent.
As shown in Patent Document 8, as a method in which the optical path of the OCT optical system does not pass through the Galilean-type objective lens of the physical microscope, there is a method in which the OCT optical system is provided under the objective lens. There was a problem that it was not possible to secure a sufficient working space between them.

On the other hand, in the Greenough stereomicroscope, as shown in FIG. 11A, the optical axis (O400L) of the observation optical system for the left eye and the optical axis (O400R) of the observation optical system for the right eye are obliquely crossed. , An objective lens through which these optical axes are commonly transmitted is not provided, and each optical system has an objective lens (401). As shown in FIG. 11B, the optical axis (A402) of the variable magnification lens and the optical axis (A401) of the objective lens are not eccentric, residual aberration can be corrected, and they occur in the left and right eyes. There is no technical problem that chromatic aberration of magnification and coma occur on the opposite sides of the left and right eyes. Further, since the Greenough type physical microscope does not use a large-diameter objective lens, an OCT optical system can be independently provided between the left and right observation optical systems.
However, in the Greenough type physical microscopic boundary, as shown in FIG. 11A, the focus position (Q400L) of the observation optical system for the left eye does not overlap with the focus position (Q400R) of the observation optical system for the right eye. As shown in FIG. 11C, there is a problem that the focus difference in the periphery is reversed in the images of the left and right eyes.
In addition, since the Greenough stereomicroscope diagonally intersects two independent observation optical systems, it has to be mechanically complicated, and there is an inconvenience that it is difficult to assemble the variable magnification optical system. It was.

Therefore, an object of the present invention is to solve the technical problems of the conventional ophthalmic microscope, to correct the residual aberration, and to make the residual aberration almost even on the left and right sides for binocular vision. To provide a suitable ophthalmic microscope. Another object of the present invention is to provide an ophthalmic microscope in which the objective lens can be made small in diameter and the OCT optical system can be easily installed.

As a result of diligent studies, the present inventors have eliminated the large-diameter objective lens through which the left and right observation optical systems commonly transmit, and provided objective lenses in each of the left and right observation optical systems, thereby eccentricity of the lens. It has been found that the problem can be solved, the residual aberration can be corrected, and the objective lens can be made smaller in diameter so that the OCT optical system can be easily installed. Further, the present inventors make the left and right observation optical systems by forming the objective lens as a lens group having at least a first lens, an optical element for changing the direction of the optical axis, and a second lens. It has been found that the optical axes can be crossed by the objective lens without oblique crossing. Furthermore, the present inventors have found that by providing an SLO optical system that guides a light beam substantially coaxial with the optical axis of the OCT optical system to the eye to be inspected, the portion of the eye to be inspected scanned by the OCT optical system can be observed without deviation. The present invention has been completed. Specifically, the present invention comprises the following technical matters.

(1) The present invention includes an illumination optical system for illuminating the eye to be inspected, an observation optical system for the left eye and an observation optical system for the right eye for observing the eye to be inspected illuminated by the illumination optical system. In an ophthalmic microscope comprising a system and an OCT optical system that scans the measurement light for inspecting the eye to be inspected by optical coherence stromography.
In the ophthalmic microscope, the optical axis of the observation optical system for the left eye and the optical axis of the observation optical system for the right eye are substantially parallel.
The observation optical system for the left eye and the observation optical system for the right eye each have an objective lens.
The objective lens includes a first lens, an optical element that changes the direction of the optical axis, and a lens group having at least a second lens.
The objective lens changes the direction of the optical axis of the left eye observation optical system and the direction of the optical axis of the right eye observation optical system so as to intersect each other on the side of the eye to be inspected.
It further has an SLO optical system that scans visible light, near-infrared light, or light rays that are infrared rays and guides the light to the eye to be inspected so as to be substantially coaxial with the optical axis of the OCT optical system. The present invention relates to an ophthalmic microscope characterized in that the portion of the eye to be inspected scanned by the OCT optical system can be observed.
(2) The ophthalmic microscope of the present invention preferably has a deflection optical element that commonly scans the measurement light of the OCT optical system and the light beam of the SLO optical system.
(3) In any of the ophthalmic microscopes, it is preferable that the optical element for changing the direction of the optical axis is a wedge prism.
(4) In any of the ophthalmic microscopes, it is preferable that the first lens is a concave lens having a negative power and the second lens is a convex lens having a positive power.
(5) In any of the ophthalmic mirror microscopes, the first lens, the optical element for changing the direction of the optical axis, and the second lens are arranged in this order from the side of the eye to be inspected. If so,
The optical axis of the first lens of the left eye observation optical system and the optical axis of the first lens of the right eye observation optical system are inclined in a direction in which they intersect each other on the side of the eye to be inspected. It is preferable to have.
(6) In any of the ophthalmic microscopes, the first lens, the optical element for changing the direction of the optical axis, and the second lens are arranged in this order from the side of the eye to be inspected. If so,
The optical axis of the second lens of the left eye observation optical system and the optical axis of the second lens of the right eye observation optical system are inclined in a direction away from each other on the side of the eye to be inspected. Is preferable.

According to the present invention, there is provided an ophthalmic microscope suitable for binocular vision, which enables correction of residual aberration and has residual aberration that is almost even on the left and right. Further, according to the present invention, there is provided an ophthalmic microscope in which an objective lens, which is an optical component constituting an ophthalmic microscope, can have a small diameter and an OCT optical system can be easily installed. Further, according to the present invention, it has an SLO optical system that guides a light beam substantially coaxial with the optical axis of the OCT optical system to the eye to be inspected, thereby observing the eye to be inspected without any deviation from the image obtained by the OCT optical system. A capable ophthalmic microscope is provided.

It is a front view which shows typically the structure of the optical system of the ophthalmic microscope of 1st Embodiment of this invention. It is a side view which shows typically the structure of the optical system of the ophthalmic microscope of 1st Embodiment of this invention. It is a drawing which shows typically the optical composition of the OCT unit used in the ophthalmic microscope of the 1st Embodiment of this invention. It is sectional drawing which shows typically the arrangement of the lens and the arrangement of the optical path around the objective lens in the ophthalmic microscope of the 1st Embodiment of this invention. FIG. 4A shows the arrangement of the lens around the objective lens, and FIG. 4B shows the arrangement of the optical path around the objective lens. It is a front view which shows typically the optical composition of the objective lens in the ophthalmic microscope of 1st Embodiment of this invention. FIG. 5 (A) shows the configuration of the objective lens used in the ophthalmic microscope of the first embodiment, and FIG. 5 (B) shows the direction of the optical axis of each lens constituting the objective lens. It is a drawing which shows typically the display part which displays the OCT image and SLO image acquired by the ophthalmologic microscope of 1st Embodiment. It is sectional drawing which shows typically the arrangement of the optical path around the objective lens in the ophthalmic microscope of the 2nd embodiment and the ophthalmic microscope of the 3rd embodiment of the ophthalmic microscope of the present invention. FIG. 7 (A) shows the arrangement of the optical path around the objective lens of the ophthalmic microscope of the second embodiment, and FIG. 7 (B) shows the optical path around the objective lens of the ophthalmic microscope of the third embodiment. Indicates the arrangement of. It is a front view which shows typically the optical composition of the objective lens in the ophthalmic microscope of the 4th Embodiment of this invention. FIG. 8A shows the configuration of the objective lens used in the ophthalmic microscope of the fourth embodiment, and FIG. 8B shows the direction of the optical axis of each lens constituting the objective lens. It is a front view which shows typically the optical composition of the objective lens in the ophthalmic microscope of the 5th Embodiment of this invention. FIG. 9A shows the configuration of the objective lens used in the ophthalmic microscope of the fifth embodiment, and FIG. 9B shows the direction of the optical axis of each lens constituting the objective lens. It is a schematic diagram which showed the Galileo type stereomicroscope which is a prior art, and the image observed by the stereomicroscope to the left and right eyes. FIG. 10 (A) is a schematic view showing the configuration of the optical system of the observation optical system for the left and right eyes of the Galilean telescope, and FIG. 10 (B) is the light of each lens of the Galilean telescope. It is a schematic diagram which shows the axis, and FIG. 10C is a schematic diagram which shows the image observed by the left and right eyes. It is a schematic diagram which showed the Greenough type stereomicroscope which is a prior art, and the image observed by the stereomicroscope to the left and right eyes. FIG. 11 (A) is a schematic view showing the configuration of the optical system of the observation optical system for the left and right eyes of the Greenough type physical microscopic boundary, and FIG. 11B is the light of each lens of the Greenough type physical microscopic boundary. It is a schematic diagram which shows the axis, and FIG. 11C is a schematic diagram which shows the elephant observed by the left and right eyes.

1. 1. Outline of the ophthalmic microscope of the present invention The ophthalmic microscope of the present invention includes an illumination optical system for illuminating the eye to be inspected, an observation optical system for the left eye and an observation optical system for the right eye for observing the eye to be inspected illuminated by the illumination optical system. The present invention relates to an ophthalmic microscope including an observation optical system having an observation optical system and an OCT optical system that scans measurement light for inspecting an eye to be inspected by optical coherence stromography.
Since the ophthalmic microscope of the present invention has objective lenses with smaller diameters in the left eye observation optical system and the right eye observation optical system, respectively, the left eye observation optical system and the right eye observation optical system It is not necessary to use a large-diameter objective lens that transmits light in common. Therefore, the eccentricity between the optical axis of the objective lens and the optical axis of the lens in front of the objective lens becomes small, and the residual aberration can be corrected. Further, in the ophthalmic microscope of the present invention, it is not necessary to use an objective lens having a large diameter, and the objective lens can be made smaller in diameter, so that an OCT optical system can be easily installed.
The ophthalmic microscope of the present invention uses a lens group having at least a first lens, an optical element for changing the direction of the optical axis, and a second lens as an objective lens. With such an objective lens, the directions of the optical axis of the observation optical system for the left eye and the optical axis of the observation optical system for the right eye are changed so as to intersect each other on the side of the eye to be inspected. Therefore, in the ophthalmic microscope of the present invention, the optical axis of the observation optical system for the left eye and the optical axis of the observation optical system for the right eye are substantially parallel to each other in the ophthalmic microscope, and the optical axis is closer to the eye to be inspected than the objective lens. The two optical axes can be crossed, and there is no need for a complicated mechanism in which the left and right observation optical systems are arranged obliquely as in the case of a Greenough stereomicroscope.
Here, the optical axis of the observation optical system for the left eye and the optical axis of the observation optical system for the right eye are not coaxial because they intersect on the side of the eye to be inspected. Therefore, the optical axis of the OCT optical system cannot be coaxial with both the optical axis of the observation optical system for the left eye and the optical axis of the observation optical system for the right eye at the same time. Therefore, the elephant observed by the observation optical system and the elephant obtained by the OCT optical system are misaligned, and accurate alignment becomes difficult.
However, in the ophthalmic microscope of the present invention, an SLO optical system that scans visible light, near infrared rays, or infrared rays and guides the light to the eye to be inspected so as to be substantially coaxial with the optical axis of the OCT optical system is further provided. Have. With this SLO optical system, it is possible to observe the eye to be inspected without deviating from the image obtained by the OCT optical system. For example, the shape of the fundus surface is imaged by the SLO optical system, and this is displayed on a part of the display unit (display), and the tomographic image obtained by the OCT optical system is superimposed or displayed on the display unit in association with the image. By displaying it on other parts, the observer can accurately grasp which part of the fundus surface the tomographic image corresponds to.

In the present invention, the "ophthalmic microscope" refers to a medical or examination device capable of magnifying and observing an eye to be inspected, including not only for humans but also for animals. The “ophthalmic microscope” includes, but is not limited to, a fundus camera, a slit lamp, a microscope for ophthalmic surgery, and the like.
The ophthalmic microscope of the present invention is used for observing (imaging) a magnified image of an eye to be inspected in medical treatment or surgery in the field of ophthalmology. The site to be observed may be any part of the patient's eye, for example, the cornea or iris in the anterior eye, the corner, the vitreous, the crystalline lens, the ciliary body, or the like, and the retina in the posterior eye. Or choroid or vitreous. Further, the observation target portion may be a peripheral portion of the eye such as an eyelid or an orbit.

The ophthalmic microscope of the present invention can have a function as another ophthalmic apparatus in addition to the function as a microscope for magnifying and observing the eye to be inspected. In addition to OCT, examples of functions as other ophthalmic devices include laser treatment, axial length measurement, refractive power measurement, and higher-order aberration measurement. Other ophthalmic devices include arbitrary configurations that allow the examination, measurement, and imaging of the eye to be examined by optical techniques.
The ophthalmic microscope of the present invention can include a control unit for controlling the position and inclination of each lens, a light source, and a display unit for displaying an captured image. Further, these control units and display units may be separate from the ophthalmic microscope.

In the present invention, the "illumination optical system" includes an optical element for illuminating the eye to be inspected. The illumination optical system may further include a light source, but may be one that guides natural light to the eye to be inspected.

In the present invention, the "observation optical system" includes an optical element that enables the eye to be inspected to be observed by the return light reflected and scattered by the eye to be inspected illuminated by the illumination optical system. Is. In the present invention, the observation optical system includes an observation optical system for the left eye and an observation optical system for the right eye, and when parallax is generated in the images obtained by the left and right observation optical systems, binocular vision is used. It is also possible to observe three-dimensionally.
Further, the "observation optical system" of the present invention may be one that allows the observer to directly observe the eye to be inspected through an eyepiece or the like, or one that can be observed by receiving light from an image sensor or the like and imaging it. It may be present, or it may have both functions.

In the present invention, the optical element used in the "illumination optical system" or the "observation optical system" is not limited to these, but for example, a lens, a prism, a mirror, an optical filter, an aperture, and a diffraction grating. , A polarizing element or the like can be used.

In the present invention, the optical axis of the observation optical system for the left eye and the optical axis of the observation optical system for the right eye are "substantially parallel" in the ophthalmic microscope. It means that the main paths in the microscope are almost parallel, and a part of the optical axis may be non-parallel, and the main paths should be parallel in the range of 5 ° or less. Just do it. However, in order to facilitate the arrangement of the lenses of the optical system, it is preferable to make them parallel as close to 0 ° as possible, and it is preferable to make them parallel in a range of 3 ° or less.

In the present invention, the "objective lens" and the "objective lens for OCT" refer to a lens or a lens group provided on the side of the eye to be inspected in an ophthalmic microscope. For example, when the objective lens is composed of three lens groups, the third lens from the side of the eye to be inspected is the objective lens. When the objective lens is composed of four lens groups, the fourth lens from the side of the eye to be inspected is the objective lens. However, the front lens (loupe) that is temporarily inserted between the objective lens and the eye to be inspected is not included in the "objective lens" in the present invention.

In the present invention, the "optical element that changes the direction of the optical axis" may be any optical element that can change the direction of the optical path, and is not limited to these, but the optical path is changed by refraction / reflection. A wedge prism, a longoid type prism capable of changing the position and orientation of the optical axis, and the like can be used.

The "visible light, near-infrared or infrared light" used in the SLO optical system of the ophthalmic microscope of the present invention is any light that includes wavelengths in the visible region, near-infrared region or infrared region. It may be a light ray, but it is preferably a highly directional light ray. More preferably, a laser beam is used.
Further, the SLO optical system is "substantially coaxial with the optical axis of the OCT optical system" if the directions of the optical axes are almost the same in the main region between the objective lens of the ophthalmologic microscope and the eye to be inspected. Well, there may be some deviation. Here, since both the optical path of the OCT optical system and the optical path of the SLO optical system are scanned, the direction of light oscillates, but the optical axis of the optical system at the center thereof may be substantially coaxial. Even if there is a slight deviation in the direction of the optical axis, it may be less than 6 °, more preferably less than 4 °, and even more preferably less than 1 °.

The ophthalmic microscope of the present invention has an OCT optical system and an SLO optical system, but from the viewpoint of miniaturizing the apparatus, it is preferable to use a part of the OCT optical system and the SLO optical system as a shared optical system. .. In particular, it is preferable to share a deflection optical element that scans the measurement light of the OCT optical system and the light beam of the SLO optical system.
When a part of the optical system is shared, the optical axis of the OCT optical system and the optical axis of the SLO optical system are substantially coaxial on the side to be inspected, and the measurement light of the OCT optical system and the optical system of the SLO optical system are on the detection system side. It is preferable to separate it from the light beam. In this case, the measurement light and the light beam can be separated by, for example, a dichroic mirror, an optical filter, or the like by utilizing characteristics such as the wavelength and deflection of the light.

When the measurement light of the OCT optical system and the light beam of the SLO optical system are merged and both are scanned by the same deflection optical element, the scanning range of the OCT optical system and the scanning range of the SLO optical system are the same. Therefore, the alignment of both images becomes easier.
The deflection optical element shared by the OCT optical system and the SLO optical system may be any optical element capable of scanning light by changing the direction of light. For example, but not limited to these, optical elements having reflecting parts that change direction, such as galvano mirrors, polygon mirrors, rotating mirrors, and MEMS (Micro Electro Mechanical Systems) mirrors, deflection prism scanners, and the like. An optical element that can change the direction of light by an electric field, an acoustic optical effect, or the like can be used, such as an AO element.

2. 2. First Embodiment Hereinafter, an example of the embodiment of the present invention will be described in detail with reference to the drawings.
1 to 6 are drawings schematically showing a first embodiment which is an example of an ophthalmic microscope of the present invention. FIG. 1 is a front view schematically showing the configuration of the optical system of the ophthalmic microscope of the first embodiment, and FIG. 2 is a side view of the configuration of the optical system. 3 is a drawing schematically showing the optical configuration of the OCT unit, FIG. 4 is a cross-sectional view schematically showing the arrangement of the lens and the arrangement of the optical path around the objective lens, and FIG. 5 is a sectional view schematically showing the arrangement of the optical path. It is a front view which shows typically the optical composition of the objective lens. FIG. 6 is a schematic view showing a display unit for displaying the OCT image and the SLO image.

As shown in the front view of FIG. 1, the optical system of the ophthalmic microscope (1) is an observation optical system consisting of an observation optical system (400L) for the left eye and an observation optical system (400R) for the right eye of the observer. It has a system, an OCT optical system (500), and an SLO optical system (1500).
Further, as shown in the side view of FIG. 2, the optical system of the ophthalmic microscope (1) further includes an illumination optical system (300). The observation optical system (400) is used for magnifying and observing the eye to be inspected (8) illuminated by the illumination optical system (300).
As shown in FIGS. 1 and 2, the observation optical system (400), the OCT optical system (500), the SLO optical system (1500), and the illumination optical system (300) are for ophthalmology shown by a single point chain line. It is housed in the microscope body (6).

In FIG. 1, the optical axis of the observation optical system (400L) for the left eye is shown by a dotted line (O-400L), and the optical axis of the observation optical system (400R) for the right eye is shown by a dotted line (O-400R). The optical axis of the OCT optical system is indicated by a dotted line (O-500).

As shown in FIG. 1, the optical axis (O-400L) of the observation optical system for the left eye and the optical axis (O-400R) of the observation optical system for the right eye are arranged in the ophthalmic microscope main body (6). It is parallel.
Therefore, the ophthalmic microscope (1) of the first embodiment does not need to have a complicated mechanism in which the left and right observation optical systems are arranged so as to intersect each other as in the Greenough stereomicroscope.

As shown in FIG. 1, the left and right observation optical systems (400L, 400R) each have an objective lens (401). The objective lens (401) is an objective lens composed of a lens group, and includes a first lens (401a), an optical element (401b) that changes the direction of the optical axis, and a second lens (401c). ing.
In the first embodiment, a wedge prism is used as the optical element (401b) for changing the direction of the optical axis, and the base direction is inside (base-in). The wedge prisms change the directions of the optical axes (O-400L, O-400R) of the left and right observation optical systems so that they intersect each other on the side of the eye to be inspected.

In the first embodiment, the first lens (401a) is a concave lens having a negative power. The optical axes of the left and right first lenses are inclined inward (directions in which they intersect each other on the side of the eye to be inspected).
The second lens (401c) is a convex lens having a positive power.

The objective lens (401) used in the ophthalmic microscope of the first embodiment has a single large-diameter lens through which the optical axes of the left and right observation optical systems are commonly transmitted, as in the conventional Galilean telescope. It is not a lens, but an objective lens that the left and right observation optical systems have independently. Therefore, as shown in FIG. 1, the objective lens (401) can have a small aperture, and the OCT optical system (500) can be easily installed between the left and right observation optical systems (400L, 400R). Can be done.
Further, as shown in FIG. 1, the left and right objective lenses (401) are oriented so as to intersect the optical axes (O-400L, O-400R) of the left and right observation optical systems on the side of the eye to be inspected. Therefore, it is possible to observe the same part of the eye to be inspected with both eyes with the left and right eyes.

Hereinafter, the ophthalmic microscope of the first embodiment will be described in more detail.
As shown in FIG. 2, the illumination optical system (300) illuminates the eye to be inspected (8), and includes an illumination light source (9), an optical fiber (301), an outlet diaphragm (302), and a condenser lens ( 303), an illumination field diaphragm (304), a collimating lens (305), and a reflection mirror (306). The optical axis of these illumination optical systems (300) is shown by a dotted line (O-300) in FIG.

The illumination light source (9) is provided outside the main body of the ophthalmic microscope (6). One end of the optical fiber (301) is connected to the illumination light source (9). The other end of the optical fiber is arranged at a position facing the condenser lens (303) inside the main body of the ophthalmic microscope (6). The illumination light output from the illumination light source (9) is guided by the optical fiber (301) and incident on the condenser lens (303).
An exit aperture diaphragm (302) is provided at a position facing the exit port (fiber end on the condenser lens (303) side) of the optical fiber (301). The exit aperture diaphragm (302) acts to block a part of the exit port of the optical fiber (301). When the blocking area by the emission port diaphragm (302) is changed, the emission area of the illumination light is changed. Thereby, the irradiation angle by the illumination light can be changed.

The illumination field diaphragm (304) is provided at a position (x position) optically conjugate with the front focal position (U0) of the objective lens (401). The collimating lens (305) converts the illumination light that has passed through the illumination field diaphragm (304) into a parallel luminous flux. The reflection mirror (306) reflects the illumination light converted into a parallel luminous flux by the collimating lens (305) toward the eye to be inspected (8). The reflected light passes through the illumination objective lens (7) and is applied to the eye to be inspected (8).
The illumination light (a part of) irradiated to the eye to be inspected (8) is reflected and scattered by the tissue of the eye to be inspected such as the cornea and the retina. The reflected / scattered return light (also referred to as “observation light”) is incident on the observation optical system (400).

As shown in FIG. 1, the left and right observation optical systems (400L, 400R) are an objective lens (401), a variable magnification lens (402), a beam splitter (403), an imaging lens (404), and an image correction lens, respectively. It includes a vertical prism (405), an eye width adjusting prism (406), a field diaphragm (407), and an eyepiece lens (408). The beam splitter (403) has only an observation optical system (400R) for the right eye.
The variable magnification lens (402) is a lens group including a plurality of zoom lenses (402a, 402b, 402c). Each zoom lens (402a, 402b, 402c) can be moved along the optical axes (O-400L, O-400R) of the left and right observation optical systems by a scaling mechanism (not shown). As a result, the magnifying magnification when observing or photographing the eye to be inspected (8) is changed.

As shown in FIG. 1, the beam splitter (403) of the observation optical system (400R) for the right eye transfers a part of the observation light guided from the eye to be inspected (8) along the observation optical path for the right eye. Separate and lead to the imaging optical system. The photographing optical system includes an imaging lens (1101) and a television camera (1102).
The television camera (1102) includes an image sensor (1102a). The image sensor (1102a) is composed of, for example, a CCD (Charge Coupled Devices) image sensor, a CMOS (Complementary Metal Oxide Semiconductor) image sensor, or the like. As the image pickup device (1102a), one having a two-dimensional light receiving surface (area sensor) is used.
The light receiving surface of the image sensor (1102a) is arranged at a position optically conjugate with the front focal position (U0) of the objective lens (401).
The beam splitter and the photographing optical system may be in both the left and right observation optical systems. A three-dimensional image can be obtained by acquiring images with parallax between the left and right image sensors.
The image of the TV camera can be used for tracking the OCT observation site based on the acquired signal or image as well as acquiring the image of the observation site. If the eye to be inspected moves during OCT scanning due to fixation microtremor of the inspected eye or surgical operation, the tomographic image obtained by OCT will shift, but the movement of the fundus will be based on the image obtained by the TV camera. By detecting and scanning the OCT optical system according to the movement of the fundus, it is possible to obtain an OCT tomographic image without deviation.

The image erecting prism (405) converts the inverted image into an erect image. The eye width adjusting prism (406) is an optical element for adjusting the distance between the left and right observation optical paths according to the eye width (distance between the left eye and the right eye) of the observer. The visual field diaphragm (407) limits the observer's visual field by blocking the peripheral region in the cross section of the observation light. The field diaphragm (407) is provided at a position (X position) conjugate with the front focal position (U0) of the objective lens (401).
The observation optical system (400L, 400R) may be configured to include a stereo variator configured to be removable from the optical path of the observation optical system. The stereo variator is an optical axis position changing element for changing the relative positions of the optical axes (O-400L, O-400R) of the left and right observation optical systems guided by the left and right variable magnification lens systems (402), respectively. is there. The stereo variator is retracted to, for example, a retracted position provided on the observer side with respect to the optical path of the observation optical system.

As shown in FIG. 1, when observing the retina of the fundus, the anterior lens (14) is placed on the optical axes O-400L, O-400R, and O-500 in front of the eye to be inspected by a moving means (not shown). Will be inserted. In this case, the anterior focal position (U0) of the objective lens (401) is conjugate with the fundus retina (8a).
When observing the anterior segment of the cornea, iris, etc., the anterior lens is detached from the front of the eye to be inspected, and the anterior focal position (U0) is aligned with the anterior segment.

As shown in FIG. 1, the OCT optical system (500) includes an OCT unit (10), an optical fiber (501), a collimating lens (502), an illumination field diaphragm (503), scanners (504a, 504b), and relay optics. The system (505), the first lens group (506), the reflection mirror (508), the second lens group (507), and the objective lens for OCT (509) are included.

The OCT unit (10) divides the light from the OCT light source having low coherence (short coherence distance) into the measurement light and the reference light. The measurement light is guided by the OCT optical system (500) and irradiated to the eye to be inspected (8), is reflected and scattered in the tissue of the eye to be inspected, and is guided to the OCT unit (10) as return light. The OCT unit (10) detects the interference between the return light of the measurement light and the reference light. This makes it possible to obtain a tomographic image of the tissue of the eye to be inspected.

As shown in FIG. 1, the OCT unit (10) is provided outside the ophthalmic microscope main body (6), but one end of the optical fiber (501) is connected to the ophthalmic microscope main body. It is connected to (6). The measurement light generated by the OCT unit (10) is emitted from the other end of the optical fiber (501). The emitted measurement light is a collimating lens (502), an illumination field aperture (503), a dichroic mirror (1501), a scanner (504a, 504b), a relay optical system (505), a first lens group (506), and a reflection mirror (501). The return light of the measurement light that is irradiated to the eye to be inspected (8) via the second lens group (507) and the objective lens for OCT (509) and is reflected and scattered by the tissue of the eye to be inspected (8) is It travels in the same path in the opposite direction and is incident on the other end of the optical fiber (501).

As shown in FIG. 1, the collimating lens (502) converts the measurement light emitted from the other end of the optical fiber (501) into a parallel luminous flux. The collimating lens (502) and the other end of the optical fiber (501) are configured to be relatively movable along the optical axis of the measurement light. In the first embodiment, the collimating lens (502) is configured to be movable, but the other end of the optical fiber (501) may be configured to be movable along the optical axis of the measurement light.
The illumination field diaphragm (503) is conjugate with the front focal position (U0) of the objective lens (401).
The dichroic mirror (1501) is composed of a reflective member that transmits the measurement light of the OCT optical system (500) without reflecting it.

The scanners (504a, 504b) in the OCT optical system are deflecting optical elements that two-dimensionally deflect the direction of the measurement light, which is converted into a parallel luminous flux by the collimating lens (502). The scanners are a first scanner (504a) having a reflective surface that can rotate around the first axis, and a second scanner (504b) that has a reflective surface that can rotate around the second axis that is orthogonal to the first axis. ) Is included in the galvano mirror. A relay optical system (505) is provided between the first scanner (504a) and the second scanner (504b). When the distance between the first scanner (504a) and the second scanner (504b) is shortened, the relay optical system (505) may not be provided.

The first lens group (506) is configured to include one or more lenses, and the second lens group (507) is also configured to include one or more lenses. The reflection mirror (508) between the first lens group (506) and the second lens group (507) turns the light toward the eye to be inspected.
Further, an OCT objective lens (509) is provided on the side close to the eye to be inspected (8). The OCT objective lens (509) is configured to be movable along the optical axis, and the focus of the OCT optical system can be adjusted by controlling the position of the OT objective lens. This makes it possible to adjust the focal point of the OCT optical system to a position different from the focal point of the observation optical system.
The OCT objective lens (509) may have an optically conjugate relationship with a member such as a galvanometer mirror, and in that case, the aperture of the objective lens of the OCT optical system can be reduced.

As shown in FIG. 1, the ophthalmic microscope (1) of the present invention further has an SLO optical system (1500). The SLO optical system (1500) includes an SLO light source (16), an optical fiber (1502), a collimating lens (1503), an illumination field aperture (1504), a dichroic mirror (1501), a half mirror (1505), and an optical aperture (1506). , A condenser lens (1507), a reflected light detector (1508), and an image creating unit (1509).
The SLO light source (16) is provided outside the ophthalmic microscope main body (6), but one end of the optical fiber (1502) is connected to the SLO light source (16) so as to be connected to the ophthalmic microscope main body (6). .. The light beam generated by the SLO light source (16) is emitted from the other end of the optical fiber (1502). The emitted light beam passes through the collimating lens (1503) and the illumination field aperture (1504), is reflected by the half mirror (1505), and is further reflected by the dichroic mirror (1501), and is measured by the OCT optical system (500). It merges coaxially with the light.

As shown in FIG. 1, the combined light rays of the SLO optical system (1500) are two-dimensionally scanned by the optical scanners (504a, 504b) in the same manner as the measurement light of the OCT optical system (500). By using optical scanners (504a, 504b) that require a complicated mechanism in common for the OCT optical system (500) and the SLO optical system (1500), the device can be miniaturized and reduced in cost.
In the ophthalmic microscope of the present invention, it is also possible to provide separate optical scanners for each of the OCT optical system and the SLO optical system and scan the OCT optical system and the SLO optical system independently. In this case, it is possible to scan different parts of the observed surface at the same time.
The light rays of the SLO optical system (1500) scanned by the optical scanners (504a, 504b) are the relay optical system (505), the first lens group (506), the reflection mirror (508), the second lens group (507), and the like. The eye to be inspected (8) is irradiated via an OCT objective lens (509) or the like. Here, the optical axis (O-500) of the SLO optical system guided to the eye to be inspected (8) is coaxial with the optical axis (O-500) of the OCT optical system. Then, the return light of the light beam reflected / scattered by the tissue of the eye to be inspected (8) travels in the opposite direction along the same path, is reflected by the dichroic mirror (1501), passes through the half mirror (1505), and has an optical aperture. (1506), it is detected by the reflected light detector (1508) via the condenser lens (1507). The detected signal is converted into an image by the image creation unit (1509).

As shown in FIG. 1, the dichroic mirror (1501) transmits the measurement light of the OCT optical system (500) and reflects the light rays of the SLO optical system (1500). As a result, the measurement light of the OCT optical system (500) and the light rays of the SLO optical system (1500) can be merged and separated.
The half mirror (1505) reflects a part of the light rays of the SLO optical system (1500) and transmits a part of the light rays. The half mirror (1505) can separate the light source side and the light receiving side of the SLO optical system (1500).
The optical aperture (1506) is conjugate with the anterior focal position (U0) of the objective lens (2), and the condenser lens (1507) collects the light rays reflected and scattered by the eye to be inspected (8).

The reflected light detector (1508) has a photodetector that detects weak light rays reflected and scattered by the eye to be inspected (8), and is composed of, for example, an APD (Avalanche photodiode) or a photomultiplier tube. ing. The detection signal from the reflected light detector (1508) is sent to the image creation unit (1509). The light beam from the SLO light source (16) is irradiated to the eye to be inspected (8) while being scanned by the optical scanners (504a and 504b), and the light beam reflected / scattered by the eye to be inspected (8) is detected by the reflected light detector (1508). By doing so, the scan data of the eye to be examined (8) can be obtained. The image creation unit (1509) creates an image of the eye to be inspected (8) based on the scan data. This image is sent to a display so that the morphology of the tissue of the eye to be examined can be observed.
It is also possible to track the movement of the test site during OCT scanning based on the signal or image obtained by SLO. By tracking, it is possible to correct the fixation tremor of the eye to be inspected during scanning by OCT and the deviation of the observation site due to the surgical operation.

FIG. 3 is a drawing schematically showing an optical configuration of an OCT unit (10) used in the ophthalmic microscope of the first embodiment.
The OCT may be an OCT of another type such as a spectral domain type OCT in addition to the Fourier domain type OCT illustrated below.
As shown in FIG. 3, the OCT unit (10) divides the light emitted from the OCT light source unit (1001) into a measurement light (LS) and a reference light (LR), and the measurement light (LR) passing through another optical path. It constitutes an interferometer that detects the interference between the LS) and the reference light (LR).
The OCT light source unit (1001) is configured to include a wavelength scanning type (wavelength sweep type) light source capable of scanning (sweeping) the wavelength of emitted light, similar to a general swept source type OCT device. The OCT light source unit (1001) changes the output wavelength with time at a near-infrared wavelength that is invisible to the human eye. The light output from the OCT light source unit (1001) is indicated by reference numeral L0.

The light L0 output from the OCT light source unit (1001) is guided by the optical fiber (1002) to the polarization controller (1003), and its polarization state is adjusted. The polarization controller (1003) adjusts the polarization state of the light L0 guided in the optical fiber (1002) by applying external stress to the looped optical fiber (1002), for example.
The light L0 whose polarization state is adjusted by the polarization controller (1003) is guided by the optical fiber (1004) to the fiber coupler (1005) and divided into the measurement light (LS) and the reference light (LR).

As shown in FIG. 3, the reference light (LR) is guided by the optical fiber (1006) to the collimator (1007) to become a parallel luminous flux. The reference light LR that has become a parallel luminous flux is guided to the corner cube (1010) via the optical path length correction member (1008) and the dispersion compensation member (1009). The optical path length correction member (1008) acts as a delay means for matching the optical path lengths (optical distances) of the reference light (LR) and the measurement light (LS). The dispersion compensating member (1009) acts as a dispersion compensating means for matching the dispersion characteristics of the reference light (LR) and the measurement light (LS).
The corner cube (1010) turns back the traveling direction of the reference light (LR) which has become a parallel luminous flux by the collimator (1007) in the opposite direction. The optical path of the reference light (LR) incident on the corner cube (1010) is parallel to the optical path of the reference light (LR) emitted from the corner cube (1010). Further, the corner cube (1010) is movable in the direction along the incident optical path and the outgoing optical path of the reference light (LR). This movement changes the length of the optical path (reference optical path) of the reference light (LR).

As shown in FIG. 3, the reference light (LR) via the corner cube (1010) passes through the dispersion compensating member (1009) and the optical path length correction member (1008), and is focused from the parallel light beam by the collimator (1011). It is converted into a light beam, incident on the optical fiber (1012), and guided by the polarization controller (1013) to adjust the polarization state of the reference light (LR).
The polarization controller (1013) has, for example, the same configuration as the polarization controller (1003). The reference light LR whose polarization state is adjusted by the polarization controller (1013) is guided to the attenuator (1015) by the optical fiber (1014), and the amount of light is adjusted under the control of the arithmetic control unit (12). The reference light (LR) whose light amount is adjusted by the attenuator (1015) is guided to the fiber coupler (1017) by the optical fiber (1016).

As shown in FIG. 3, the measurement light (LS) generated by the fiber coupler (1005) is guided to the optical fiber (501), while the measurement light emitted from the optical fiber (501) is shown in FIG. It is guided to the collimating lens (502) so as to be. Then, as shown in FIG. 1, the measurement light incident on the collimating lens (502) includes the illumination field diaphragm (503), the dichroic mirror (1501), the scanners (504a, 504b), the relay optical system (505), and the first. The eye to be inspected (8) is irradiated via one lens group (506), a reflection mirror (508), a second lens group (507), and an OCT objective lens (509). The measurement light is reflected and scattered at various depth positions of the eye to be inspected (8). The backscattered light of the light measured by the eye to be inspected (8) travels in the same direction as the outward path in the opposite direction, is guided to the fiber coupler (1005), and passes through the optical fiber (1018) as shown in FIG. Then, it reaches the fiber coupler (1017).

The fiber coupler (1017) synthesizes (interferes) the measurement light (LS) incidented via the optical fiber (1018) and the reference light (LR) incident via the optical fiber (1016). ) Generates interference light. The fiber coupler (1017) generates a pair of interference lights (LC) by branching the interference light between the measurement light (LS) and the reference light (LR) at a predetermined branching ratio (for example, 50:50). .. The pair of interference lights (LC) emitted from the fiber coupler (1017) are guided to the detector (1021) by two optical fibers (1019, 1020), respectively.

The detector (1021) has, for example, a pair of photodetectors that detect each pair of interference lights (LC), and a balanced photodiode (hereinafter referred to as "BPD") that outputs the difference between the detection results. ). The detector (1021) sends the detection result (detection signal) to the arithmetic control unit (12). The arithmetic control unit (12) forms a cross-sectional image by, for example, performing a Fourier transform or the like on the spectral distribution based on the detection result obtained by the detector (1021) for each series of wavelength scans (for each A line). To do. The arithmetic control unit (12) causes the displayed image (13) to display the formed image.

In this embodiment, a Michelson type interferometer is adopted, but for example, any type of interferometer such as a Mach-Zehnder type can be appropriately adopted.

FIG. 4 is a cross-sectional view schematically showing the arrangement of lenses and the arrangement of optical paths around the objective lens in the ophthalmic microscope of the first embodiment. FIG. 4A shows the arrangement of the lens around the objective lens, and FIG. 4B shows the arrangement of the optical path around the objective lens.
As shown in FIG. 4A, an illumination objective lens (7) is provided in the lens barrel of the ophthalmic microscope main body (6). The illumination objective lens (7) is provided with three through holes (7a, 7b, 7c), and two through holes (7a, 7c) are provided with a first lens (401a). There is.

As shown in FIG. 4B, the optical path of the observation optical system for the left eye (P-400L) and the optical path of the observation optical system for the right eye (P-400R) are contained in the lens barrel of the microscope main body (6) for ophthalmology. ), The optical path of the illumination optical system (P-300), and the optical path of the OCT optical system (P-500). Of these, the optical path (P-400L) of the observation optical system for the left eye passes through the first lens (401a) in the through hole (7c) of the illumination objective lens (7) shown in FIG. 4 (A). The optical path (P-400R) of the observation optical system for the right eye is the first lens (401a) in the through hole (7a) of the illumination objective lens (7) shown in FIG. 4 (A). It is transparent. Further, the optical path (P-500) of the OCT optical system passes through the through hole (7b) of the illumination objective lens (7) shown in FIG. 4 (A).
In the ophthalmic microscope of the first embodiment of the present invention, since each optical system has its own objective lens, it is possible to independently control the optical path of each optical system.

FIG. 5 is a front view schematically showing the optical configuration of the objective lens in the ophthalmic microscope of the first embodiment.
FIG. 5 (A) shows the configuration of the objective lens used in the ophthalmic microscope of the first embodiment, and FIG. 5 (B) shows the direction of the optical axis of each lens constituting the objective lens.

As shown in FIG. 5A, the objective lens (401) used in the ophthalmic microscope of the first embodiment is the first lens (401a) and an optical element (401b) that changes the direction of the optical axis. ), And a second lens (401c). The first lens (401a) is a concave lens having a negative power, the optical element (401b) that changes the direction of the optical axis is a wedge prism, and the second lens (401c) is a positive lens. It is a convex lens with power.
As shown in FIG. 5 (B), the optical axis (A-401a) of the first lens is inclined inward (the direction in which they intersect each other on the side of the eye to be inspected).

FIG. 6 is a schematic view of a display unit that displays an OCT image and an SLO image acquired by the ophthalmic microscope of the first embodiment.
As shown in FIG. 6, the display unit (13) has a display screen (1301). The display screen (1301) is provided with six image display units (1302 to 1307). These image display units are a first vertical cross-sectional image display unit (1302), a cross-sectional image display unit (1303), a processed image display unit (1304), a front image display unit (1305), and a second vertical section, respectively. The surface image display unit (1306) and the operation guide image display unit (1307).
An image of the fundus surface acquired by the SLO optical system is displayed on the front image display unit (1305), and the first vertical cross-sectional image display unit (1302), the cross-sectional image display unit (1303), and the second The vertical cross-sectional image display unit (1306) displays a tomographic image of the fundus acquired by the OCT optical system. The processed image display unit (1304) is provided with an image (processed image) obtained by performing a predetermined processing process on an image displayed on another image display unit, for example, angiography (angiography), projection. (Projection, fundus tomographic image), an image for detecting a lesion such as diabetic retinopathy is displayed. In FIG. 6, an image of the fundus surface obtained by the SLO optical system is displayed on the processed image display unit (1304), and the lesion portion is colored and displayed. Here, the location of the lesion is identified by image analysis of the tomographic image obtained by OCT.

As shown in FIG. 6, the front image display unit (1305) shows an observation image of the fundus surface, but the horizontal direction is the x-axis and the vertical direction is the y-axis. Then, a tomographic image of the xy cross section of the fundus is displayed on the cross section image display unit (1303).
Then, in the first vertical section image display unit (1302) and the second vertical section image display unit (1306), the fundus along the two cross sections in the z direction indicated by the dotted line in the front image display unit (1305). The tomographic image of is displayed. A tomographic image of the yz section is displayed on the first vertical section image display unit (1302), and a tomographic image of the xz section is displayed on the second vertical section image display unit (1306).
On the operation guide image display unit (1307), for example, an image obtained by superimposing a site to be operated on on an image obtained before the operation can be displayed.

Here, in the ophthalmic microscope of the first embodiment, since the optical axis of the OCT optical system and the optical axis of the SLO optical system are coaxial, the observation image of the surface of the fundus surface acquired by the SLO optical system is used. , There is no positional deviation from the tomographic image of the fundus obtained by the OCT optical system. Therefore, there is no positional deviation between the observation image of the fundus surface displayed on the front image display unit (1305) and the tomographic image on the xy cross section displayed on the cross-section image display unit (1303), so that accurate alignment can be achieved. It will be possible. Further, the two cross sections shown by the dotted lines in the front image display unit (1305), the tomographic image of the yz cross section displayed in the first vertical cross section image display unit (1302), and the second vertical cross section image display unit (1306). There is no positional deviation from the tomographic image of the xz cross section displayed in, and accurate alignment is possible.

3. 3. Second and Third Embodiments Next, examples of other embodiments of the present invention will be described with reference to the drawings.
FIG. 7 schematically shows the arrangement of optical paths around the objective lens in the ophthalmic microscope of the second embodiment and the ophthalmic microscope of the third embodiment, which are other examples of the ophthalmic microscope of the present invention. It is a cross-sectional view.
FIG. 7 (A) shows the arrangement of the optical path around the objective lens of the ophthalmic microscope of the second embodiment, and FIG. 7 (B) shows the optical path around the objective lens of the ophthalmic microscope of the third embodiment. Indicates the arrangement of.

As shown in FIG. 7A, in the ophthalmic microscope of the second embodiment, the optical path (P-400L) of the observation optical system for the left eye is contained in the lens barrel of the ophthalmic microscope main body (6). In addition to the optical path of the observation optical system for the right eye (P-400R), the optical path of the illumination optical system (P-300), and the optical path of the OCT optical system (P-500), the optical path for the left eye of the sub-observation optical system. (P-400SL) and an optical path for the right eye (P-400SR) are arranged.
The sub-observation optical system is used by an assistant observer other than the main observer (operator) to observe the eye to be inspected.
In the ophthalmic microscope of the present invention, since the observation optical system and the OCT optical system each have their own objective lenses, it is possible to arrange the optical paths of many optical systems independently in this way.

As shown in FIG. 7B, in the ophthalmic microscope of the third embodiment, the optical path (P-400L) of the observation optical system for the left eye is located near the center of the lens barrel of the ophthalmic microscope main body (6). The optical path (P-400R) of the observation optical system for the right eye, the optical path (P-300) of the illumination optical system, and the optical path (P-500) of the OCT optical system are arranged so as to be concentrated. As a result, the angle formed by each optical path can be reduced without overlapping the optical path of the observation optical system and the optical path of the OCT optical system, thus expanding the range in which shape observation with a microscope and tomographic observation with OCT can be performed at the same time. be able to.

4. Configuration of Objective Lens The objective lens used in the ophthalmic microscope of the present invention is an objective composed of at least a first lens, an optical element that changes the direction of the optical axis, and a second lens. It is a lens.
Here, the first lens, the optical element that changes the direction of the optical axis, and the second lens may be arranged in any order.
Further, another lens or an optical element can be added to these lenses to form a lens group used as an objective lens.

In addition, any lens can be used as the first lens and the second lens, and they can be appropriately designed so that the eye to be inspected can be focused and magnified. Preferably, either one of the first lens and the second lens is a convex lens having a positive power, and the other is a concave lens having a negative power.

As the optical element for changing the direction of the optical axis, any optical element capable of changing the direction of the optical path can be used, and the optical element is not limited to these, but for example, refraction / reflection. A prism that changes the optical path can be used. As such a prism, for example, a wedge prism, a longoid type prism capable of changing the position and orientation of the optical axis, or the like can be used.

When the first lens, the optical element that changes the direction of the optical axis, and the second lens are arranged in this order from the side of the eye to be inspected, the optical element that changes the direction of the optical axis left and right. The direction of the optical axis of the observation optical system is changed so that it intersects on the side of the eye to be inspected. Therefore, the optical axis of the first lens of the observation optical system for the left eye and the optical axis of the first lens of the observation optical system for the right eye are inclined in a direction in which they intersect each other on the side of the eye to be inspected. Is preferable. Here, the "optical axis of the lens" is different from the "optical axis of the optical system" and means the optical axis of the lens alone.

Further, when the first lens, the optical element for changing the direction of the optical axis, and the second lens are arranged in this order from the side of the eye to be inspected, the second lens of the observation optical system for the left eye is used. It is preferable that the optical axis of the lens and the optical axis of the second lens of the observation optical system for the right eye are inclined in a direction away from each other on the side of the eye to be inspected.
With such a configuration, it is possible to greatly improve the problem that the focus difference in the periphery is reversed in the images of the left and right eyes as shown in FIG.

5. Fourth Embodiment FIG. 8 is a front view schematically showing an optical configuration of an objective lens in the ophthalmic microscope of the fourth embodiment, which is another example of the ophthalmic microscope of the present invention.
FIG. 8A shows the configuration of the objective lens used in the ophthalmic microscope of the fourth embodiment, and FIG. 8B shows the direction of the optical axis of each lens constituting the objective lens.

As shown in FIG. 8A, the objective lens (401) used in the ophthalmic microscope of the fourth embodiment is the first lens (401a) and an optical element (401b) that changes the direction of the optical axis. ), And a second lens (401c). The first lens (401a) is a concave lens having a negative power, the optical element (401b) that changes the direction of the optical axis is a wedge prism, and the second lens (401c) is a positive lens. It is a convex lens with power.

As shown in FIG. 8B, the optical axes (A-401c) of the second lens are inclined in a direction away from each other on the side of the eye to be inspected.
With such a configuration, it is possible to greatly improve the problem that the focus difference in the periphery is reversed in the images of the left and right eyes as shown in FIG.

6. Fifth Embodiment FIG. 9 is a front view schematically showing an optical configuration of an objective lens in the ophthalmic microscope of the fifth embodiment, which is another example of the ophthalmic microscope of the present invention.
FIG. 9A shows the configuration of the objective lens used in the ophthalmic microscope of the fifth embodiment, and FIG. 9B shows the direction of the optical axis of each lens constituting the objective lens.

As shown in FIGS. 9A and 9B, the objective lens (401) used in the ophthalmologic microscope of the fifth embodiment has a wedge prism (401b) and negative power from the side of the eye to be inspected. A concave lens (401a) having a positive power and a convex lens (401c) having a positive power are arranged in this order.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and changes in conditions that do not deviate from the gist are all within the scope of the present invention.

The ophthalmic microscope of the present invention is an ophthalmic microscope that can correct residual aberrations, has aberrations and focus differences that are nearly even on the left and right, and is suitable for binocular vision, and has a small objective lens. Since the OCT optical system can be easily installed, it can be used in the optical equipment industry and the medical equipment-related industry.

1 Ophthalmic microscope 2 Subject 300 Illumination optical system 301 Optical fiber 302 Emission light aperture 303 Condenser lens 304 Illumination field aperture 305 Collimating lens 306 Reflection mirror 400 Observation optical system 400L Observation optical system for left eye 400R Observation optical system for right eye System 401 Objective lens 401a First lens 401b Optical element that changes the direction of the optical axis 401c Second lens 402 Variable magnification lens 402a, 402b, 402c Zoom lens 403 Beam splitter 404 Imaging lens 405 Image erecting prism 406 Eye width Adjusting prism 407 Field aperture 408 Eyepiece lens 500 OCT Optical system 501 Optical fiber 502 Collimating lens 503 Illumination field aperture 504a, 504b Scanner 505 Relay optical system 506 First lens group 507 Second lens group 508 Reflective mirror 509 Objective lens for OCT 6 Ophthalmology Microscope body 7 Illumination objective lens 7a, 7b, 7c Through hole 8 Eye to be inspected 8a Retina 9 Illumination light source 10 OCT unit 1001 OCT light source unit 1002 Optical fiber 1003 Polarization controller 1004 Optical fiber 1005 Fiber coupler 1006 Optical fiber 1007 Collimeter 1008 Optical path Length correction member 1009 Dispersion compensation member 1010 Corner cube 1011 Collimeter 1012 Optical fiber 1013 Polarization controller 1014 Optical fiber 1015 Attenuator 1016 Optical fiber 1017 Fiber coupler 1018 Optical fiber 1019 Optical fiber 1020 Optical fiber 1021 Detector 1101 Imaging lens 1102 TV camera 1102a Imaging element 12 Arithmetic control unit 13 Display unit 1301 Display screen 1302 First vertical cross-sectional image display unit 1303 Cross-sectional image display unit 1304 Processed image display unit 1305 Front image display unit 1306 Second vertical cross-sectional image display unit 1307 Operation guide image Display 14 Front lens 1500 SLO Optical system 1501 Dycroic mirror 1502 Optical fiber 1503 Collimated lens 1504 Illumination field aperture 1505 Half mirror 1506 Optical aperture 1507 Condensing lens 1508 Reflected light detector 1509 Image creation unit A-401 Optical axis of objective lens A-402 Optical axis of variable magnification lens A-401a Optical axis of first lens A-401c Optical axis of second lens O-300 Optical axis of illumination optical system O-400 Optical axis of observation optical system O-400L Optical axis of observation optical system for left eye O-400R Optical axis of observation optical system for right eye O-500 Optical axis of OCT optical system, Optical axis of SLO optical system P-300 Optical path P-300 of illumination optical system 400L Optical path for left eye observation optical path P-400R Optical path for right eye observation optical system P-400SL Optical path for left eye of secondary observation optical system P-400SR Optical path for right eye of secondary observation optical system P-500 OCT Optical path of optical system, optical path of SLO optical system Q400L Focus position of observation optical system for left eye Q400R Focus position of observation optical system for right eye V400L Image for left eye V400R Image for right eye L0 OCT Output from light source unit Optics LC Interference Optics LS Measurement Optics LR Reference Optics U0 Front Focus Position

Claims (6)

An illumination optical system that illuminates the eye to be inspected, an observation optical system that has an observation optical system for the left eye and an observation optical system for the right eye for observing the eye to be inspected illuminated by the illumination optical system, and optical coherence stromography. In an ophthalmic microscope provided with an OCT optical system that scans the measurement light for inspecting the eye to be inspected.
In the ophthalmic microscope, the optical axis of the observation optical system for the left eye and the optical axis of the observation optical system for the right eye are substantially parallel.
The observation optical system for the left eye and the observation optical system for the right eye each have an objective lens.
The objective lens includes a first lens, an optical element that changes the direction of the optical axis, and a lens group having at least a second lens.
The objective lens changes the direction of the optical axis of the left eye observation optical system and the direction of the optical axis of the right eye observation optical system so as to intersect each other on the side of the eye to be inspected.
It further has an SLO optical system that scans visible light, near-infrared light, or light rays that are infrared rays and guides the light to the eye to be inspected so as to be substantially coaxial with the optical axis of the OCT optical system. An ophthalmic microscope characterized in that a region including the portion of the eye to be inspected scanned by the OCT optical system can be observed. The ophthalmologic microscope according to claim 1, further comprising a deflecting optical element that commonly scans the measurement light of the OCT optical system and the light beam of the SLO optical system. The ophthalmic microscope according to claim 1 or 2, wherein the optical element for changing the direction of the optical axis is a wedge prism. The ophthalmic use according to any one of claims 1 to 3, wherein the first lens is a concave lens having a negative power, and the second lens is a convex lens having a positive power. microscope. In the objective lens, the first lens, the optical element that changes the direction of the optical axis, and the second lens are arranged in this order from the side of the eye to be inspected.
The optical axis of the first lens of the left eye observation optical system and the optical axis of the first lens of the right eye observation optical system are inclined in a direction in which they intersect each other on the side of the eye to be inspected. The ophthalmic microscope according to any one of claims 1 to 4, wherein the microscope is provided. In the objective lens, the first lens, the optical element that changes the direction of the optical axis, and the second lens are arranged in this order from the side of the eye to be inspected.
The optical axis of the second lens of the left eye observation optical system and the optical axis of the second lens of the right eye observation optical system are inclined in a direction away from each other on the side of the eye to be inspected. The ophthalmic microscope according to any one of claims 1 to 5, wherein the microscope is characterized by the above.