JPS60210241A - Eyeground photographing apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fundus photographing device used for a-viewing and photographing the fundus in eye hospitals and the like.

In recent years, with the spread of fundus cameras, the diagnostic functions of ophthalmology and cardiovascular disease have been significantly improved.However, in general, when fundus photography is performed using a fundus camera, the positional relationship between the eye being examined and the camera is extremely delicate. Even if there is a slight difference or movement of the eyes, flare or ghosts may appear in the photographed image, resulting in poor image quality. In particular, in non-mydriatic fundus photography that does not use mydriatic agents, there is a natural limit to the number of images that can be taken, and in cases such as two-group examinations, the impact of failure is extremely large.

The purpose of the present invention is to improve such problems, and to make it possible to immediately judge whether or not it is necessary to take pictures again by creating a frame memory of images taken on film, etc. and monitor images, such as shots. The purpose of the device is to provide a fundus photographing device that is equipped with an observation optical system that guides light from an observation light source into the eye to be examined, captures and displays a fundus image, and a system that guides light from an observation light source into the eye to be examined. A fundus camera comprising a photographing optical system for recording a guided fundus image, the camera comprising: guiding at least a part of the light reflected by the fundus emitted from the observation light source to an imaging means of the observation optical system; and an output of the imaging means. Accordingly, a monitor image equivalent to the recorded image is stored in the image storage means and is also displayed on the display means.

The present invention will be explained in detail based on illustrated embodiments.

FIG. 1 is a configuration diagram showing a first embodiment of the present invention, and
is a light observation source consisting of a tungsten lamp or the like, and the light emitted from this observation light source L passes through a condenser lens 2 and a microink mirror 3, and then passes through a ring-shaped opening [-1] of a Ringeslint plate 4 as shown in FIG. The section 4a is illuminated.

Here, as shown in FIG. 3, the dichroic mirror 3 is made of i+ (transmits visible light and reflects infrared rays).The light emitted from the ring-shaped opening 4a is passed through the relay lens 5. After forming an image in the vicinity of the perforated mirror 6, it is reflected, and by the objective lens 7 placed between the perforated mirror 6 and the subject's eye E, it is re-imaged near the cornea of the subject's eye E, and the fundus Ef is reflected. On the other hand, the fundus Ef
After being imaged by the objective lens 7, the light passes through the hole in the perforated mirror 6, passes through the photographic lens 8 and the dichroic mirror 9, and forms an image near the field lens 10, and then is further imaged by the reflecting mirror 11, The image is formed on the image receiving surface of the image pickup tube 13 via the relay lens 12. Furthermore, the dichroic mirror 9 used has characteristics as shown in FIG. The fundus image guided to the image pickup tube 13 is displayed on the cathode ray tube of the monitor television 14 as a fundus image Ea. In addition, near the hole of the perforated mirror 6, there are two light guides 16 and 17 that guide the light from the wide tip (15).
The tips P and Q of are arranged. A film 18 is placed behind the quick mirror 9 via a shutter (not shown), and further behind the dichroic mirror 3, a photographing light source 19 consisting of a strobe tube and a condenser lens 20 are placed 4.

Here, the tips P and Q of the light guide 16.17 are arranged near the hole of the perforated mirror 6, and the light guide 16.17 is reflected by the cornea of the eye E through the objective lens 7.
When operating the fundus camera, the light spot is again formed at a position almost conjugate with the fundus image by the objective lens 7 and projected on the cathode ray tube of the monitor television 14 as light points Pa and Qa. , it is possible to take pictures while observing and adjusting the screen of the monitor television 14. That is, focusing and determining the imaging area are performed while looking at the fundus image Ea on the screen, and the position between the fundus camera and the eye E is determined depending on whether the light points Pa and Qa can be observed well or not. be exposed.

Next, photography is performed, but in this case, the photography light source 19
is emitted. The light emitted by the photographing light source 19 passes through the dichroic mirror 3, illuminates the ring-shaped opening 4a of the ring slit 4, and then passes through the relay lens 5, the perforated mirror 6, and the objective lens 7 to illuminate the eye E to be examined. Illuminate the fundus Ef. The light reflected by the fundus Ef passes through the objective lens 7, the hole in the perforated mirror 6, the photographic lens 8, and the dichroic mirror 9, and is imaged and recorded on the film 18. In this case, the photographing light source 19 emits light by operating the shutter, but at the same time, the shutter signal causes
The circuit for obtaining a still image illustrated in FIG. 4 is now functional.

That is, the signal from the shutter circuit 21 is sent to the imaging tube 13 at the same time as the imaging light source 19 emits light, and the output from the imaging tube 13 is guided to the A/D conversion circuit 22. Here, A/D
The converted signal is stored in the frame memory 23, the stored information is input to the monitor television 14, and a fundus image Ea equivalent to the photographed image is displayed on the monitor television 14. , the image of Qa can be confirmed.

Therefore, it is possible to immediately determine whether the photograph taken on the film 18 is appropriate or not, and to immediately take necessary measures such as retaking the photograph.

FIG. 5 shows a second embodiment of the invention, in which the same reference numerals as in FIG. 1 indicate the same or equivalent parts.

The main difference from the previous embodiment shown in FIG. 1 is that a split illumination system is added.

This split illumination system is used to judge whether the film 18 of the fundus camera is correctly aligned with the fundus Ef, and includes a light source 24, a split index plate 25, a split prism 26, a reflecting mirror 27, and a relay lens 2
8. It is composed of a two-hole slit plate 29 and a beam splitter 30 installed obliquely within the illumination optical system. subry
71. The indicator plate 25 has a rectangular slit indicator 25a as shown in FIG. 6, and the two-hole slit plate 29 has two arc-shaped slit indicators forming part of a ring slit as shown in FIG. It has slit portions 29a and 29b.

Further, in this embodiment, a beam splitter 31 is inserted between the tyro-ink mirror 9 and the film 18, and a field lens 32 placed on the reflection side almost conjugate with the film 18 is followed by a reflection mirror 33 and an eyepiece. 34
A viewfinder rNl and an observation optical system are provided, and can be observed with the presbyopic eye e. Furthermore, tree nuts 1
In the example, dichroic ink mirror 3 and condenser lens 20
An infrared filter 35 is inserted between the two.

In FIG. 5, light from an observation light source 1 passes through a condenser lens 2 and a dichroic mirror 3 that acts as a beam splitter, illuminates a ring-shaped opening 4a of a ring slit 4, and illuminates a ring-shaped opening 11 4a. The light that has passed through the fundus Ef follows the same path as in the previous example. Q will be clear. The reflected light emitted from the fundus Ef passes through the objective lens 7, the hole of the perforated mirror 6, and the photographing lens 8, and then the visible light is transmitted by the tychro-ink mirror 9 having the characteristics shown in FIG. I'm willing to go. The light reflected by the beam splitter 31 forms an image in the vicinity of the field lens 32 which is almost conjugate with the film 18, passes through the reflection mirror 33 and the eyepiece 34, and is then observed by the presbyopic observer e.

On the other hand, the light reflected by the dichroic ink mirror 9 forms an image near the field lens 10, which is almost conjugate with the film 18, and then is directed to the imaging surface of the imaging tube 13 by the reflection mirror 11 and relay lens 12. An image is formed and displayed on the monitor television 147 as a fundus image Ea.

The light from the light source 24 of the Matasprint illumination system illuminates the index 25a of the split index plate 25.

The light beam that has passed through the index 25a is separated into two by the split prism 26 from the center of the index 25a. The luminous fluxes which have been reduced by N1 for 1 minute pass through the anti-Ut mirror 27 and the relay lens 28, and enter the slint portions 29a and 29b of the two-hole slint plate 29, respectively, independently. The light exiting the two-hole slint plate 29 is reflected by the beam splitter 30 and combined into the illumination optical system of the fundus camera.

(7) , 2.7' After forming a two-hole pickpocket 71-image near the hole-perforated mirror 6 by the finger frame light beam t ori-relay lens 5, -,! ;j, forms an aerial image and enters the objective lens 7; After passing through the objective lens 7, a two-hole aperture 7) image is formed again near the cornea of the eye E to be examined, and the image enters the eye E to be examined, forming an index image on the fundus Ef. And fundus Ef
This split index image that has been emitted is guided to the observation system in the same way as the fundus image Ea. This split illumination system is designed so that the split index plate 25 is always connected to the film 18.
If it is linked to the focusing mechanism of the fundus camera, the observer can use the finder a focusing system to
By observing the index image, it is possible to always take a photograph in sharp focus.

Also, a light kite illuminated by the light source 15]6.1
The tips P and Q of No. 7 are also confirmed by the observation presbyopia e through the same route as described above, and are used to adjust the distance between the eye E to be examined and the fundus camera.

Using these functions, determine the imaging area of the eye E,
Fundus photography is performed after positioning and focusing. In this embodiment, the light emitted from the photographing light source 19 passes through the condenser lens 20 and the infrared filter 35, and then enters the ring-shaped ring slit 4. The opening 4a is illuminated.

Thereafter, the fundus Ef is illuminated through the same route as in the fundus observation, and the light from the fundus Ef also reaches the filter 18 through the same route, and a fundus image is recorded. Note that the image confirmation at this time is performed in the same manner as in the previous embodiment, but in this embodiment, the focus state can also be confirmed at the same time.

In addition, in this embodiment, if the visible light part of the split indicator plate 25 is adjusted, the film 181, 1jl,
However, if there is a risk of this happening, an infrared filter may be inserted between the beam splitter 30 and the light source 24 when the photographing light source 19 emits light, or an equivalent optical shank function may be provided. . Also beam sprit,
In step 31, a total reflection mirror may be used to capture the moment of photographing.

As is clear from the above description, the fundus photographing device according to the present invention can display the fundus image recorded on the film and the monitor image of the eye on the cathode ray tube of the monitor television through the heat retention tα means. Immediately after that, you will be able to immediately find any failures in shooting or focusing, and immediately take necessary measures such as redoing the shooting! 0 to implement on ν
Becomes 17 years old.

In addition, in order to obtain a still small image of the fundus with the observation system, the imaging light I-
The imaging light and wavelength can be split without any loss, especially in the case of fluorescence imaging. Furthermore, in order to check for poor focusing or the influence of the subject's eye, it is possible to check the focus by directly capturing an infrared split or the like.

[Brief explanation of the drawing]

The drawings show an embodiment of the fundus photographing device according to the present invention, and the first embodiment
The figure is a block diagram of the first embodiment, Figure 2 is a front view of the ring slit plate, Figure 3 is a characteristic diagram of the gicroic mirror, and Figure 4 is a block circuit diagram for obtaining an image in a static manner. , FIG. 5 is a block diagram of the second embodiment, FIG. 6 is a front view of a split finger plate, and FIG. 7 is a front view of a two-hole slint plate. Is the code l 11? Light source, 2.20 is condenser lens, 3
, 9 is a tie chroic mirror, 4 is a ring slit, 6
is a mirror with a hole, 7 is an objective lens, 8 is a photographing lens, 1
3 is the imaging I6. 14 is the monitor TV, 15 is the light source, 16
．． 17 is a light kite 18 is a film, 19 is a photographing light source, 24 is a light source, 25 is a split index plate, 26 is a split prism, 29 is a two-hole slit, 30 and 31 are a beam splitter, and 34 is an eyepiece. Patent applicant Canon Co., Ltd.

Claims (1)

[Scope of Claims] 1. An observation optical system that guides the light from the RI & Dormitory light mixed light source into the subject's eye and captures and displays a fundus image, and which guides the light from the photographic light source into the subject's eye and records the fundus image. A fundus camera comprising a photographing optical system, wherein at least a part of the light reflected on the fundus emitted from the observation light source is guided to an imaging means of the observation optical system, and an output of the imaging means is used to record the recorded image in 41j. A fundus photographing device characterized by storing an equivalent monitor image in an image storage means and displaying it on a display means. 2. Introducing the light from the light source into the subject's eye <lr4 A bright optical system is provided with a means for wavelength-splitting the light flux, and the light from the observation light source reaching the subject's eye is divided into infrared light and light from the photographing light source. The fundus tM shadow device according to claim 1, wherein the light is visible light. 3. Projecting an index light toward the eye to be examined, arranging it so that the index image is formed at a position where the light flux reflected by the cornea of the eye to be examined substantially coincides with the fundus, and guiding the index image to the imaging means. A fundus photographing device according to claim 1. 4. A light splitting means is provided in the fundus photographing optical system, and the light splitting means selectively guides a fundus image to an imaging means or a finer observation means, as set forth in claim 1. fundus imaging device. 5. The light splitting means provided in the photographing optical system is
Claim 4: Infrared light flux is guided to the imaging means, and visible light flux is guided to the finer observation means (+iii).
The fundus photographing device described in Section t. 6. A focusing optical system for projecting an index onto the fundus and focusing on the fundus, and guiding a finger pillow image reflected by the fundus to the imaging means. The fundus 1-nod imaging device according to item 1. 7. A focusing optical system for projecting an index onto the fundus and focusing on the fundus is provided, and the light splitting means of 111 (setting the index image reflected on the fundus in the photographing optical system) is used. A fundus photographing device according to claim 1, which is adapted to lead to an imaging means or a finder observation means.