JP2000296113A - Fundus camera - Google Patents

Abstract

(57) [Summary] Fluorescent imaging can be performed with a small amount of light while observing with infrared light. SOLUTION: In fluorescence fundus image photographing, at the time of observation, a fluorescence excitation filter 6 is inserted into an optical path O1, and a filter
1 leaves the optical path O2. Similar to the case of photographing a color fundus image, the fundus Er is irradiated with infrared light of the halogen lamp light source 1.
Is illuminated, and a fundus image is captured by the black-and-white video camera 16. The fundus image is observed on the video monitor 18 to perform positioning and focusing. When the position and focus are achieved, the filter 11 is inserted into the optical path O2 immediately before photographing, the strobe light source 4 emits light, and the fluorescent still fundus image is captured by the black-and-white video camera 16 and recorded in the image recording means 17.

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 an ophthalmic hospital or the like.

[0002]

2. Description of the Related Art Conventionally, in the case of performing fluorescent imaging with a non-mydriatic retinal camera, imaging has been performed using color imaging means.

[0003]

However, in the above-mentioned conventional example, when performing fluorescence imaging while observing the fundus of the eye to be inspected with infrared light, the amount of light must be increased and the burden on the examinee is increased. Is multiplied.

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 performs fluorescence imaging with a small amount of light while observing with infrared light.

[0005]

According to the present invention, there is provided a fundus camera for illuminating a fundus with infrared light for observation, a flash light source for photographing, and a removable light path for an illumination light path. A fluorescence excitation filter for transmitting or blocking observation infrared light, a color fundus image photographing means, a black-and-white video camera for fundus observation, and an observation infrared ray detachably provided in a fundus imaging optical path of the black-and-white video camera. A fluorescent filter that blocks or transmits light.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the illustrated embodiment. FIG. 1 shows a configuration diagram of a fundus camera according to a first embodiment. A halogen lamp light source 1 for observation, on an illumination optical path O1, cuts short-wavelength light of 800 nm or less and transmits infrared light more than that. An infrared filter 2, an imaging lens 3, a strobe light source 4 for imaging, a ring slit 5 conjugated to a pupil of the eye E, a fluorescence excitation filter 6 inserted into an optical path O1 at the time of fluorescence imaging, and a lens 7 are sequentially arranged. ing.

On the optical path O2 in front of the eye E, an objective lens 8, a perforated mirror 9 conjugate to the anterior segment of the eye E, and a fluorescent filter driven and inserted by a solenoid 10 into the optical path O2 during fluorescent imaging. A color image photographing means 14 such as a filter 11, an imaging lens 12, an optical path switching mirror 13, and a digital camera is arranged. A relay lens 15 and a black-and-white video camera 16 are arranged on the optical path O3 in the reflection direction of the optical path switching mirror 13. Have been. The output of the color image photographing means 14 is output to an image recording means 17 such as a magneto-optical disk.
The output of the monochrome video camera 16 is connected to an image recording means 17 and a video monitor 18.

FIG. 2 shows the spectral transmission characteristics of the fluorescent filters 6 and 11, wherein the horizontal axis represents wavelength (nm) and the vertical axis represents transmittance.
The fluorescence excitation filter 6 transmits the excitation wavelength light of 400 to 500 nm and the infrared light for observation. Further, the fluorescent filter 11 blocks the light of these wavelengths together, and
m fluorescence wavelength light is transmitted.

In photographing a color fundus image, at the time of observation, the fluorescent filters 6 and 11 are separated from the optical paths O1 and O2, respectively, and the luminous flux from the halogen lamp light source 1 is cut off by the infrared filter 2 except for the infrared light. An image is formed on the ring slit 5 by the lens 3, reflected by the peripheral mirror of the perforated mirror 9, and projected on the fundus Er of the eye E through the objective lens 8. The reflected image from the fundus Er passes through the objective lens 8, the hole of the perforated mirror 9, the imaging lens 12 again, is reflected by the optical path switching mirror 13, and is reflected by the relay lens 1.
The image is formed on a black-and-white video camera 16 via the monitor 5 and is observed by a video monitor 18.

At the time of photographing, the optical path switching mirror 13 is flipped up to the position indicated by the dotted line, and the strobe light source 4 emits light. The luminous flux of the strobe light source 4 illuminates the fundus Er by tracing the same optical path O1 as during observation, and the image of the fundus Er is captured by the color image capturing unit 14 via the similar optical path O2, and the image recording unit 17
Will be recorded.

In the fluorescence fundus image photographing, at the time of observation, the excitation filter 6 is inserted into the optical path O1, and the filtering filter 11 is separated from the optical path O2. The fundus Er is illuminated with the infrared light of the halogen lamp light source 1 as in the case of the color fundus image photographing, and the fundus image is captured by the monochrome video camera 16.
The fundus image is observed on the video monitor 18 to perform positioning and focusing. Fluorescent filter 1 during shooting
1 is inserted into the optical path O2, and the strobe light source 4 emits light. The optical path switching mirror 13 picks up the fluorescent still fundus image with the black-and-white video camera 16 without flipping it up, records it in the image recording means 17, and displays the still image on the monitor 18 for confirmation. For the next photographing, the fluorescent filter 11
From the optical path O2 to return the display on the monitor 18 to an infrared moving image.

FIG. 3 is a block diagram of the fundus camera of the second embodiment, and FIG. 4 shows the spectral characteristics of the fluorescent filter. Members having the same functions are denoted by the same reference numerals. In the illumination optical system of the optical path O1, a light splitting member 20 that reflects visible light and transmits infrared light is disposed between the lens 3 and the ring slit 5, and on the optical path O4 in the incident direction of the light splitting member 20, A fluorescence excitation filter 21, a lens 22, and a photographing strobe light source 4 that block fluorescence wavelength light and observation infrared light and transmit excitation wavelength light are arranged. Further, a fluorescence excitation filter 23 that transmits the fluorescence wavelength light and the observation infrared light is disposed on the optical path O3, and the other configuration is the same as that of FIG.

In fluorescent imaging, the fluorescent filter 21
23 are inserted into the optical paths O4 and O3, respectively. Observation is performed by illuminating the fundus Er with infrared light from the halogen lamp light source 1, capturing an image with the monochrome video camera 16, and displaying the fundus image on the video monitor 18. In the case of photographing, the strobe light source 4 emits light, is excited with light having a wavelength of 400 to 500 nm, captures a fluorescent still image with the black-and-white video camera 16, and records it in the recording means 17. At this time, the fundus Er by infrared light together with the fluorescent image
The halogen lamp light source 1 is turned off at least between frames in which the strobe light source 4 emits light so that an image is not projected. Alternatively, the fluorescent filter 11 may be inserted at the time of imaging as in the first embodiment.

FIG. 5 shows the spectral transmission characteristics of the fluorescent filters similar to those shown in FIG. 2, and these fluorescent filters can be used when performing visible light fluorescence photography and infrared fluorescence photography. The visible fluorescence excitation filter 25 and the infrared fluorescence excitation filter 26 are separately prepared and used separately, and the fluorescence filtration filter 27 is common to visible and infrared light, transmits visible fluorescence and infrared fluorescence, and blocks excitation wavelength light. 1 and 2 are possible for the configuration of the device.
It is sufficient that the infrared filter 2 can be separated from the optical path O1.

In the apparatus having the structure shown in FIG. 1, a fluorescence excitation filter 25 or 26 is used in place of the fluorescence excitation filter 6, and a fluorescence filtration filter 27 is used in place of the fluorescence filtration filter 11.
Use Visible fluorescence imaging is performed in the same manner as in the first embodiment. In infrared fluorescence imaging, the infrared filter 2 is separated from the optical path O1, and the fluorescence excitation filter 26 is inserted. 700-80
Observation is performed with light having an excitation wavelength of 0 nm, and a fluorescent filter 27 is inserted at the moment of photographing.

3 uses a fluorescence excitation filter 25 or 26 in place of the fluorescence excitation filter 21 and a fluorescence filter 2 instead of the fluorescence filter 23.
7 is used. Visible fluorescence imaging is performed in the same manner as in the second embodiment. In infrared fluorescence imaging, the infrared filter 2 is detached from the optical path O1, and the fluorescence filter 26 and the filter 27 are inserted.

FIG. 6 is a block diagram of the illumination optical system of the third embodiment, and the other parts are the same as those of the second embodiment of FIG. In the fluorescence imaging, the fluorescence filtration filter 23 is inserted into the optical path, observation is performed with infrared light from the halogen lamp light source 1, and the fluorescence excitation filter 21 is inserted into the optical path O1 by the actuator 30 in synchronization with the emission of the strobe light source 4 for imaging. I do.

[0018]

As described above, the fundus camera according to the present invention performs observation using a fluorescence excitation filter that transmits or blocks observation infrared light, and blocks or transmits the observation infrared light immediately before photographing. By inserting a fluorescent filter and taking a picture, it is possible to take a fluorescent picture by an image pickup means without passing through a color separation optical member, and it is possible to reduce a photographing light amount, reduce glare, reduce a power supply size, and take a photographing interval. Can be shortened.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a first embodiment.

FIG. 2 is a graph showing a spectral transmittance of a fluorescent filter.

FIG. 3 is a configuration diagram of a second embodiment.

FIG. 4 is a graph showing a spectral transmittance of a fluorescent filter.

FIG. 5 is a graph showing a spectral transmittance of a fluorescent filter.

FIG. 6 is a configuration diagram of a main part of a third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Halogen lamp light source 2 Infrared filter 4 Strobe light source 6, 21, 25, 26 Fluorescence excitation filter 10 Solenoid 11, 23, 27 Fluorescence filtration filter 14 Color image imaging means 16 Black and white video camera 17 Image recording means 18 Video camera 20 Light division Member 30 Actuator

Claims (1)

[Claims] 1. An illumination means for illuminating the fundus with infrared light for observation, a flash light source for photographing, a fluorescence excitation filter provided in the illumination optical path so as to be able to pass or block infrared light for observation, and a color fundus. Image photographing means, a black and white video camera for fundus observation,
A fundus camera, comprising: a fluorescence filtering filter that cuts or transmits observation infrared light that is removably provided in the fundus imaging optical path of the black-and-white video camera.