JPH05111466A - Ophthalmic equipment - Google Patents

Abstract

(57) [Summary] [Objective] It is an object to provide an ophthalmologic apparatus capable of properly capturing an image with a TV camera without adjusting the light amount of the same illumination light source step by step. [Composition] A TV camera 32 having sensitivity characteristics ranging from the visible light wavelength region to the infrared light wavelength region and having different sensitivity characteristics in the visible light wavelength region and the infrared light wavelength region is provided, and the same illumination is provided. In the ophthalmologic apparatus that illuminates the subject's eye 18 with the light source 3 to perform observation and photography, it is based on the fact that the sensitivity characteristics differ with the switching of the illumination wavelength from one of visible light illumination and infrared light illumination to the other. In order to correct the output fluctuation of the TV camera 32, output fluctuation correction means 33 is provided which corrects the output fluctuation in conjunction with switching of the illumination wavelength.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a TV having sensitivity characteristics ranging from the visible light wavelength region to the infrared light wavelength region, and having different sensitivity characteristics between the visible light wavelength region and the infrared light wavelength region.
The present invention relates to improvement of an ophthalmologic apparatus equipped with a camera.

[0002]

2. Description of the Related Art Conventionally, there has been known an ophthalmologic apparatus in which an eye to be inspected is imaged by a TV camera and the eye to be inspected is imaged, while an image of the eye to be inspected is displayed on a monitor television. The TV camera has sensitivity characteristics ranging from the visible light wavelength region to the infrared light wavelength region, and is capable of performing visible light observation photography and infrared light observation photography.
It is also possible to perform visible fluorescence observation photography and infrared fluorescence observation photography.

[0003]

By the way, as shown in FIG. 1, the sensitivity of a TV camera is substantially constant in the visible light wavelength region, but the sensitivity gradually increases as it moves to the infrared light wavelength region. Has the property of decreasing. Therefore, if infrared light observation is performed with infrared illumination while adjusting the light amount of the illumination light source for observation so that proper imaging can be performed in the visible light wavelength region, the sensitivity of the TV camera in the infrared light wavelength region Since the characteristics are lower than the sensitivity characteristics in the visible light wavelength region, if the light amount of the same illumination light source remains fixed, the video output of the TV camera will be smaller than the output obtained in the visible light wavelength region and underexposure will occur. Then, the image of the subject's eye projected on the television monitor is too dark. On the other hand, when observing visible light with visible light illumination while adjusting the light amount of the illumination light source so that proper imaging can be performed in the infrared light wavelength region, the sensitivity characteristic of the TV camera is infrared in the visible light wavelength region. Since it is higher than the sensitivity characteristic in the light wavelength region, the output of the TV camera becomes higher than the output obtained in the infrared light wavelength region and the exposure becomes overexposed when the light amount of the illumination light source for observation remains fixed. , The image of the subject's eye projected on the television monitor is too bright.

Therefore, conventionally, the light amount of the same illumination light source is adjusted when observing visible light and when observing infrared light. However, it is troublesome to adjust the light amount of the illumination light source for observation one by one when performing the visible light observation and photography and when performing the infrared light observation and photography. The same problem occurs when performing visible fluorescence observation photography and when performing infrared fluorescence observation photography.

Therefore, it is an object of the present invention to provide an ophthalmologic apparatus capable of properly capturing an image with a TV camera without adjusting the light amount of the same illumination light source one by one.

[0006]

In order to solve the above-mentioned problems, an ophthalmologic apparatus according to the present invention has sensitivity characteristics ranging from the visible light wavelength region to the infrared light wavelength region, and has a visible light wavelength region. TVs with different sensitivity characteristics in the infrared light wavelength range
In an ophthalmologic apparatus that is equipped with a camera and illuminates the eye to be inspected with the same illumination light source for imaging, the sensitivity characteristics associated with switching the illumination wavelength from one of visible light illumination and infrared light illumination to the other are In order to correct the output fluctuation of the TV camera based on the difference, an output fluctuation correction means for correcting the output fluctuation in conjunction with the switching of the illumination wavelength is provided.

[0007]

According to the ophthalmologic apparatus of the present invention, the output variation correcting means adjusts the output variation of the TV camera in association with the switching of the illumination wavelength from one of the visible light illumination and the infrared light illumination to the other. to correct.

[0008]

FIG. 2 shows an optical system of a fundus camera as an ophthalmologic apparatus. In FIG. 2, 1 is an illumination optical system and 2 is a photographing optical system. The illumination optical system 1 includes a halogen lamp 3 as an observation light source, a condenser lens 4, a xenon tube 5 as a photographing light source, a condenser lens 6, an infrared light cut filter 6 ', a visible light cut filter 7', a ring diaphragm 7, and a relay. The lens 8, the mirror 9, and the relay lens 10 are generally included. The photographing optical system 2 includes an objective lens 11, a perforated mirror 12, a variable power optical system 13 ', a focusing lens 13, and an imaging lens.
It consists of 14, quick return mirrors 15, 16 and film 17. The objective lens 11 faces the subject's eye 18. The ring-shaped diaphragm 7 is provided with respect to the relay lenses 8 and 10 and the objective lens 11 at a position substantially conjugate with the pupil 19 of the eye 18 to be inspected.

At the time of observation with visible light illumination, an infrared light cut filter 6'is inserted in the optical path of the illumination optical system 1. Visible light cut filter 7'for observation with infrared light
Is inserted in the optical path of the illumination optical system 1. Both the infrared light cut filter 6'and the visible light cut filter 7'are retracted from the optical path of the illumination optical system 1 at the time of fluorescence observation photography.

Illumination light from the halogen lamp 3 includes condenser lenses 4 and 6, a ring diaphragm 7, a relay lens 8, a mirror 9, a relay lens 10, a perforated mirror 12, and an objective lens 11.
It is guided to the eye to be inspected 18 through and illuminates the fundus 20 of the eye to be inspected 18. The illumination light becomes ring-shaped illumination light when passing through the pupil 19 of the subject's eye 18. At the time of photographing the eye to be inspected, the xenon tube 5 is caused to emit light by operating a photographing switch (not shown), and the fundus 20 is similarly illuminated.

The light flux from the fundus 20 reaches the quick return mirror 15 via the objective lens 11 and the hole 12a of the perforated mirror 12, the focusing lens 13 and the imaging lens 14. Here, the quick return mirror 15 is retracted from the optical path of the photographing optical system 2 when observing visible light with the eyepiece optical system described later, and when observing with a TV camera described later,
It is inserted in the optical path of the photographing optical system 2. The quick return mirror 15 constitutes a part of the television image receiving system 21, and the television image receiving system 21 will be described later.

The quick return mirror 16 is inserted into the optical path of the photographing optical system 2 when observing the visible light illumination by the eyepiece optical system, and the light flux from the fundus 20 is reflected by the quick return mirror 16 and the eyepiece optical system 22. It enters the eye 25 of the examiner through the mirror 23 and the eyepiece lens 24. As a result, the fundus 20 of the subject's eye 18 is observed.

The mirror 9 and the relay lens 8 of the illumination optical system 1
Exciter filter for visible fluorescence in the optical path between
26 and an exciter filter 27 for infrared fluorescence can be inserted. Further, a visible fluorescence barrier filter 28 and an infrared fluorescence barrier filter 29 can be inserted between the perforated mirror 12 and the focusing lens 13 of the photographing optical system 2.

During observation photography other than fluorescence photography, the visible fluorescence exciter filter 26 and infrared fluorescence exciter filter 27 are retracted from the optical path of the illumination optical system 1, and the visible fluorescence barrier filter 28 and infrared fluorescence barrier filter are used. 29 is retracted from the optical path of the photographing optical system 2. Exciter filter for visible fluorescence for visible fluorescence observation
26 is inserted in the optical path of the illumination optical system 1. Similarly, the visible fluorescence barrier filter 28 is inserted in the optical path of the photographing optical system 2. At the time of infrared fluorescence observation photography (wavelength 800 nm to 950 nm), the infrared fluorescence exciter filter 27 is inserted into the optical path of the illumination optical system 1. Similarly, a barrier filter for visible fluorescence
29 is inserted in the optical path of the photographing optical system 2.

The television image receiving system 21 includes a reflection mirror.
30, a TV relay lens 31, and a TV camera 32 are provided. The TV camera 32 has sensitivity characteristics ranging from the visible light wavelength range to the infrared light wavelength range, and the sensitivity characteristics are different between the visible light wavelength range and the infrared light wavelength range as shown in FIG.
The output of the TV camera 32 is input to the processing circuit 34 via the gain adjusting circuit 33. A gain change signal is input to the gain adjustment circuit 33. The gain adjusting circuit 33 serves as an output fluctuation correcting means for correcting an output fluctuation of the TV camera based on a difference in sensitivity characteristic associated with switching of illumination light from one of visible light illumination and infrared light illumination to the other. In this embodiment, a gain change signal is output when the visible light cut filter 7'is inserted into the optical path of the illumination optical system 1 during visible light illumination, and the gain of the gain adjusting circuit 33 is automatically adjusted. It is supposed to be changed in the direction of increasing. Therefore, the television monitor 35 under visible light illumination
From the observation by the television monitor under infrared illumination 35
Even if the observation is switched to the observation by T
An appropriate image can be taken by the V camera 32. The processing circuit 34 outputs a video signal based on the output of the TV camera 32 and has a function of storing the fundus image as image information. The video signal is input to the television monitor 35, and the television monitor 35 displays the fundus image 36. When the infrared light illumination is switched to the visible light illumination, the gain of the gain adjusting circuit 33 of the gain adjusting circuit 33 is returned to the original state as the optical path of the visible light cut filter 7'is separated from the illumination optical system 1. It

When a photographing switch (not shown) is operated during photographing, the xenon tube 5 emits light and the fundus 20 is illuminated. At the same time, the quick return mirror 16 is retracted from the optical path of the photographing optical system 2. The light flux from the fundus 20 is guided to the film and film recording is performed. Also, when the quick return mirror 15 is inserted, electronic image recording is performed. The fundus image 36 is also displayed on the television monitor.
Displayed on 37 television screens.

Next, examples of visible light observation photography and infrared fluorescence observation photography will be described.

When the visible fluorescence observation photography and the infrared fluorescence observation photography are performed, for example, the subject is to be simultaneously injected with a visible fluorescence fluorescent agent and an infrared fluorescence fluorescent agent. .. In this embodiment, a gain change signal is input to the gain adjusting circuit 33 in response to switching from the visible fluorescence observation / photographing mode to the infrared fluorescence observation / photographing mode.
Then, the light amount of the halogen lamp 3 is adjusted so that the visible fluorescence observation can be appropriately performed. Then, when set to the visible fluorescence photographing mode, the exciter filter 26 for visible fluorescence and the barrier filter 28 for visible fluorescence are inserted into the respective optical paths of the illumination optical system 1 and the photographing optical system 2. In this state, visible fluorescence observation or photographing is performed. When performing infrared fluorescence observation or photographing during this visible fluorescence observation or photographing, the infrared fluorescence photographing mode is set. Then, the gain change signal is input to the gain adjustment circuit 33, the gain change signal is input to the gain adjustment circuit 33, and the gain adjustment circuit 33 changes in the direction in which the gain automatically increases in accordance with the switching of the mode. To be done. Further, the exciter filter 26 for visible fluorescence and the barrier filter 28 for visible fluorescence are retracted from the respective optical paths of the illumination optical system 1 and the photographing optical system 2, and the exciter filter 27 for infrared fluorescent light and the barrier filter for infrared fluorescent light are provided. 28 is inserted in each optical path of the illumination optical system 1 and the photographing optical system 2.

As a result, even when the visible fluorescence observation is switched to the infrared fluorescence observation, proper imaging can be performed without changing the light amount of the same illumination light source one by one.

When the infrared fluorescence observation is switched to the visible fluorescence observation, the gain of the gain adjusting circuit 33 is restored to the original gain.

As described above, in the embodiment, the output fluctuation correcting means is constituted by the gain adjusting circuit 33, but instead of providing the gain adjusting circuit 33, the television image receiving system between the TV relay lens 31 and the reflecting mirror 30. ND in 21 optical paths
The filter is insertable / removable, and when observing visible light, the ND filter is inserted in the optical path for observation, and when observing infrared light, the illumination optical system of the visible light cut filter 7 '. The ND filter is removed from the optical path of the television image receiving system 21 in association with the insertion of the optical path 1 into the optical path, so that the illumination light is switched from one of the visible light illumination and the infrared light illumination to the other. It is also possible to adopt a configuration that corrects the output fluctuation of the TV camera due to the difference in sensitivity characteristics.

[0022]

Since the ophthalmologic apparatus according to the present invention is configured as described above, there is an effect that a TV camera can properly capture an image without adjusting the light amount of the same illumination light source step by step.

[Brief description of drawings]

FIG. 1 is a diagram showing a wavelength sensitivity characteristic of a TV camera according to the present invention.

FIG. 2 is a diagram showing an example of an optical system of an ophthalmologic apparatus according to the present invention.

[Explanation of symbols]

 3 Halogen lamp (illumination light source for observation) 18 Eye 32 TV camera 33 Gain adjustment circuit (output fluctuation canceling means)

Claims (1)

[Claims] 1. A TV camera having sensitivity characteristics extending from the visible light wavelength region to the infrared light wavelength region, and having different sensitivity characteristics between the visible light wavelength region and the infrared light wavelength region In an ophthalmologic apparatus that illuminates the eye to be inspected with an illumination light source and performs observation and photography, a TV based on the difference in sensitivity characteristics with switching of the illumination wavelength from one of visible light illumination and infrared light illumination to the other An ophthalmologic apparatus comprising: an output fluctuation correcting unit that corrects the output fluctuation in association with the switching of the illumination wavelength in order to correct the output fluctuation of the camera.