JP3359112B2 - Fundus camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fundus camera used in mass examinations, ophthalmic clinics, and the like.

[0002]

2. Description of the Related Art Conventionally, a fundus camera performs photographing and observation by directly irradiating a portion to be photographed of a fundus of a subject's eye with illumination light and recording or photoelectrically converting the reflected light.

However, the reflected light from the fundus contains the specular reflected light from the boundary layer of each layer of the retina and the like, and the specular reflected light from the blood in the blood vessel in the retina and the choroid, and these are simultaneously observed and photographed. It is configured as follows.

[0004]

However, in the above-mentioned conventional example, the specularly reflected light from each retina layer boundary surface is
There is a problem that the contrast of a blood vessel image or the like formed by the diffuse reflected light is reduced, and that information from a choroidal blood vessel, which is an internal tissue, cannot be obtained.

An object of the present invention is to solve the above-mentioned problems,
An object of the present invention is to provide a fundus camera that blocks a part of illumination light and captures a clear fundus image by indirect illumination.

[0006]

A fundus camera according to the present invention for achieving the above object provides an indirect illumination with light of a surrounding illumination area with respect to a non-illumination area in which a substantially central portion on a fundus of an eye to be examined is shielded. An illumination optical system in which a light-shielding member for performing the illumination is provided at a position substantially conjugate with the fundus, and a photographing means for providing a mask for shielding the illumination area and photographing a fundus image of the indirectly illuminated area. Features. Further, the fundus camera according to the present invention is a fundus with a stripe-shaped or slit-shaped light-shielding member for performing indirect illumination by light in a surrounding illumination area for a non-illumination area that shields an arbitrary area on the fundus of the eye to be inspected. An illumination optical system provided at a substantially conjugate position, a photographing means for photographing a plurality of areas indirectly illuminated by moving the light shielding member or switching the plurality of light shielding members, and a plurality of photographed images obtained by the imaging means And a synthesizing means for synthesizing a fundus image.

[0007]

In the optometry apparatus having the above-described structure, a part of the illumination light is shielded by a light-shielding member, and an illumination area and a non-illumination area are formed on the fundus of the eye to be inspected. And photograph a fundus image by indirect illumination light.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the illustrated embodiments. FIG. 1 shows a configuration diagram of the present invention. In front of an eye E, an objective lens 1, a perforated mirror 2 having an opening at a central portion, a focusing lens 3, a photographing lens 4, and a switch for retracting outside the optical path during photographing. A mirror 5, a mask 6 for blocking light reflected from the illumination area, and an image sensor 7 are arranged.
The output of the imaging element 7 is connected to the television monitor 8 and the control box 9, and the control box 19 is connected to the storage means 10 and the imaging switch 11.

In the incident direction of the perforated mirror 2, the lens 1
2. A light-shielding region is formed in the fundus, and a light-shielding member 14 which can be inserted into and removed from the optical path by an insertion means 13, a lens 15, a stop 16 having a ring-shaped opening, a light source 17 for photographing comprising a strobe, and a condenser lens 18 , An observation light source 19 are arranged. On the other hand, a total reflection mirror 20, a focusing plate 21, and an eyepiece 22 are arranged in the reflection direction of the switching mirror 5. Note that the light shielding member 14 is a focusing lens 3
It is designed to be able to move along the optical path in conjunction with
Irrespective of the diopter of the eye to be examined, it is always substantially conjugate to the fundus Er.

When the light-shielding member 14 is not present in the optical path, the light beam emitted from the observation light source 19 is
The light source 17 for photography, the aperture of the aperture 16,
The light passes through the lenses 15 and 12, is reflected by the mirror portion of the perforated mirror 2, enters through the objective lens 1 from the periphery of the pupil Ep of the eye E, and illuminates the fundus Er.

The fundus image illuminated in this way is again
The light passes through the center of the Ep, the hole of the perforated mirror 2, the focusing lens 3 and the photographing lens 4, is reflected by the flip-up mirror 5 and the mirror 20, and forms an image near the focus plate 21. The examiner observes this image through the eyepiece lens 22 and prepares for imaging, such as confirmation of the imaging site, focusing, and working distance adjustment.

After the preparation for photographing is completed, the examiner operates the photographing switch 11. As a result, the flip-up mirror 5 is retracted out of the optical path, and the light blocking member 14 is inserted into the optical path by the insertion means 13. Immediately, the photographing light source 17 emits light, and the light beam passes through the opening of the stop 16 and the lens 15,
A part of the light reaches the light-shielding member 14 and is partially shielded, and the other transmitted light passes through the lens 12 and is reflected by the mirror portion of the perforated mirror 2, passes through the objective lens 1, enters the periphery of the pupil Ep, and illuminates the fundus Er. I do.

FIG. 2 shows an illuminated area A and a non-illuminated area B in the fundus Er. This non-illumination area B
Is indirectly illuminated by scattered light from the illumination area A and light transmitted through the retina or choroid. As described above, the blood vessel image mainly of the non-illuminated area B indirectly illuminated passes through the central portion of the pupil Ep, the objective lens 1, the hole of the perforated mirror 2, the focusing lens 3, and the photographing lens 4, and passes through the imaging lens 4. An image is formed on the imaging surface, and the image is displayed on the television monitor 8, further converted into a video signal, and stored in the storage unit 10. Further, since the fundus image in the illumination area A is shielded from light by the light shielding mask 6, only the fundus image in the non-illumination area B is displayed on the television monitor 8. Alternatively, the fundus images of the illumination area A and the non-illumination area B may be stored together in the storage means 10 without using the light-shielding mask 6, and only the image of the non-illumination area may be called and displayed on the television monitor 8.

In particular, when imaging a blood vessel in the choroid, an element having sensitivity to infrared light is used as the imaging element 7, and infrared light is illuminated by an infrared light source or an infrared light transmitting filter or the like. It is preferable to use as.

Further, focusing, confirmation of a photographing part, etc.
This was performed by directly observing the visible image of the fundus Er via the eyepiece 22 with the naked eye, but the fundus Er was illuminated with infrared light, and a moving image of the fundus Er due to the infrared light was captured by the imaging device 7.
The user can prepare for shooting while observing the image on the television monitor 8. Further, the light shielding member 14 in the illumination optical system is automatically inserted into the optical path in conjunction with the operation of the photographing switch 11. However, the light shielding member 14 is inserted into the optical path at an arbitrary timing. Can be provided.

As shown in FIG. 3, the light-shielding member 14 is formed in a stripe shape, is arranged in the direction of a vertical stripe with respect to the fundus Er, and driving means for scanning the vertical stripe horizontally is provided, or different light-shielding portions are provided. A plurality of vertical stripe-shaped light shielding members 14 having
Insertion means capable of inserting the light blocking member 14 into the illumination light path is provided, and as shown in FIGS. 4 (a) and 4 (b), it is also possible to photograph a plurality of fundus images where different positions are non-illuminated areas.

By cutting out the indirectly illuminated portions from these images, bonding them again, and synthesizing them, it becomes possible to form a wide-angle fundus image using indirect illumination light.
In addition, by the computer of the control box 9,
The above-described division and composition are automatically performed, and the television monitor 8
A composite fundus image can also be displayed on top.

Further, as shown in FIG. 5, the light shielding member 14 is formed in a plate shape, and a driving means for moving the light shielding member 14 in a direction perpendicular to the optical axis is provided. As shown in FIGS. 6 (a) to 6 (d), Means for scanning the light-shielding portion to obtain a plurality of different fundus images, thereby continuously taking out and synthesizing the image of the non-illuminated area, and using this means to display a moving image on the television monitor 8 indirectly using a wide-angle fundus image Can also be displayed.

In this manner, a clear fundus image of a tissue such as a choroidal blood vessel in the retina can be photographed without being affected by specular reflection light at a boundary surface of each layer of the retina. In this case, since the macular area is not directly irradiated with strong light, the degree of glare experienced by the subject can be reduced. It is possible to take multiple shots.

[0020]

As described above, the fundus camera according to the present invention provides a light shielding member in an illumination optical system to form an illumination area and a non-illumination area on the fundus, and photographs the non-illumination area. A fundus image showing a choroidal blood vessel or the like in a lower layer than the retina can be clearly photographed without being affected by specular reflection light from a boundary surface of each layer of the retina. In addition, if the non-illuminated area is moved and the image of the non-illuminated area is cut out and pasted again, a wide-angle fundus image can be automatically formed, thereby enabling simple and accurate ophthalmologic diagnosis. Becomes

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment.

FIG. 2 is an explanatory diagram of a fundus image.

FIG. 3 is a front view of a striped light shielding member.

FIG. 4 is an explanatory diagram illustrating a non-illumination area.

FIG. 5 is a front view of a plate-shaped light shielding member.

FIG. 6 is an explanatory diagram showing a non-illumination area.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Objective lens 2 Perforated mirror 3 Focusing lens 7 Image sensor 8 Television monitor 9 Control box 10 Storage means 11 Shooting switch 14 Shielding member 17 Light source for shooting 19 Light source for observation

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-55-113434 (JP, A) JP-A-55-29316 (JP, A) JP-A-2-198536 (JP, A) JP-A-3-1985 193026 (JP, A) Japanese Patent Laid-Open No. 1-195838 (JP, A) Osamu Matsuo, Masahiko Usui, Examination Method for Diseases in Ophthalmology, Medical Aoi, Edition, September 17, 1984, First Edition, P. 28-29 (58) Field surveyed (Int. Cl. ⁷ , DB name) A61B 3/00-3/16 JICST file (JOIS)

Claims (2)

(57) [Claims] 1. A non-lighting device in which a substantially central portion on a fundus of a subject's eye is shielded from light.
Indirect illumination is performed on the bright area using the light from the surrounding illumination area
Optics with a light shielding member provided at a position approximately conjugate with the fundus
System, and a mask for shielding the illumination area from light is provided.
Photographing means for photographing a fundus image of an indirectly illuminated area . 2. A non-light-shielding device for shielding an arbitrary region on the fundus of the eye to be inspected from light.
Indirect illumination is performed on the illumination area using light from the surrounding illumination area.
A stripe-shaped or slit-shaped light-shielding member to conjugate with the fundus
Moving the light blocking member and the light blocking member
Is indirectly illuminated by switching a plurality of the light shielding members.
Photographing means for photographing a plurality of areas,
Combining multiple obtained captured images to compose a fundus image
And a fundus camera.