JPH05300877A - Ophthalmologic measuring apparatus - Google Patents

Abstract

PURPOSE:To provide an ophthalmologic measuring apparatus which has a function to allow the operation of a lighting stop adapted to limit a range of lighting the eyegrounds with a simple operation. CONSTITUTION:An optical system for inspecting the eyegrounds comprises lighting systems 2-9... and observation and photographing systems 11-16. An inspector S moves a focusing lens 11 anchored on gears 18 and 19 with a lens drive section 17 to adjust focus according to the diopter of an eye to be inspected. A stop 7 is made to interlock the focusing lens 11 through a lens drive section 17 and gears 20 and 21. The stop 7 is provided in the lighting system to set a range of lighting the eyegrounds and is so arranged to act in linkage to be always conjugate with the eyegrounds Er of the eye E to be inspected with the lens drive section 17 in the operation of adjusting focus. With such an arrangement. the range of lighting the eyegrounds can be set automatically to a proper range interlocking the adjustment of focus, thereby eliminating dazzling of an examinee as in the past and getting rid of complicated manipulation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ophthalmologic measuring apparatus, and more particularly to an apparatus for illuminating the fundus of a subject's eye and receiving reflected light to evaluate the fundus image to measure the diameter of the blood vessel in the fundus.

[0002]

2. Description of the Related Art Conventionally, as a method for measuring the diameter of blood vessels in the retina, the fundus of the eye is illuminated in a range sufficiently wider than the blood vessel to be measured, and the reflected light is photographed by a TV camera, a solid-state image sensor, or the like. It is known to measure the blood vessel diameter by subjecting the obtained fundus image to filter processing, binarization processing, etc. which are generally known image processing.

Further, as in JP-A-63-264941,
It is also known that a fundus image is continuously photographed on a video tape or the like by a TV camera to analyze a change in blood vessel diameter with time.

It is considered that these are the same as the illuminating means of the conventional fundus camera, since no reference is made to the means for illuminating the fundus of the subject. So, in the following,
The problem of the conventional technique will be described with reference to the illumination means of a general fundus camera.

[0005]

The illuminating means of the fundus camera is configured to illuminate with an illumination angle of view corresponding to the angle of view to be observed or photographed.

[0006] For example, in a fundus camera configured to photograph at an angle of view of 20 °, illumination is usually performed at an angle of view slightly larger than the angle of view at 20 °. Illuminating with a slightly larger angle of view means that the illuminance illuminating the fundus is near constant when the diopter of the subject's eye is close to the reference value at the time of optical design, but as the diopter moves away from the reference value, the fundus When the illuminance at the edge of the illumination area is gradually lower than that at the center, and if this low-illumination portion is photographed, the obtained image will not have uniform brightness and will be unsightly. This is because it is not suitable for image processing.

For this reason, in a general fundus camera, the range of the photographing field angle is wider than the photographing field angle at which the diopter of the eye to be inspected can always illuminate with uniform illuminance. Must be given.

In a general fundus camera, the limitation of the angle of view of illumination is not performed by a component having one function such as a diaphragm, but by a lens barrel of a lens.

In such a configuration, the fundus of the subject is illuminated in a range wider than the angle of view for photographing, so that the subject also dazzles even the unnecessary light is made incident on the eye.

As a solution to this problem, an illumination diaphragm for limiting the range of illuminating the fundus of the eye is arranged at a position in the illumination optical system almost conjugate with the fundus of the eye, and the diaphragm is adjusted according to the diopter of the subject.
It is conceivable to control so as to have a conjugate relationship with the fundus.

However, in the conventional configuration, the examiner must operate the diaphragm so as to have a conjugate relationship with the fundus according to the diopter of the subject, and the operation of the complicated device is complicated. There is a problem that becomes.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and to provide an ophthalmologic measuring apparatus having a mechanism capable of operating an illumination diaphragm which limits the range of illuminating the fundus by a simple operation.

[0013]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an ophthalmological examination for illuminating the fundus of an eye to be examined, receiving the reflected light thereof, and evaluating a fundus image to perform a fundus examination. In the measuring device, a light source for illuminating the fundus of the eye to be examined and an illumination optical system provided with a diaphragm for limiting the illumination light at a position substantially conjugate with the fundus, and a reflected light from the fundus are received to capture or observe. When forming an image on the image plane, means for performing focusing according to the diopter of the eye to be inspected and interlocking means for moving the fundus of the eye to be inspected and the diaphragm in a conjugate relationship according to the focusing. The configuration provided is adopted.

[0014]

According to the above construction, the examiner performs focusing according to the diopter of the subject's eye while observing the fundus, so that the diaphragm provided in the illumination optical system does not conjugate with the subject's fundus. Since the position can be automatically controlled, observation or photographing can be easily performed with the same number of operations as a normal fundus camera.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in the drawings.

FIG. 1 shows the structure of an ophthalmologic measuring apparatus adopting the present invention. In FIG. 1, the luminous flux emitted from the halogen lamp 9 passes through the condenser lens 8, is limited by the diaphragm 7 that is substantially conjugate with the fundus Er of the eye E, passes through the relay lens 6, and is reflected by the total reflection mirror 5. Then, the light is reflected by the perforated total reflection mirror 10 through the ring slit 4 and the relay lenses 3 and 4, and is irradiated onto the fundus Er of the eye E through the objective lens 1. The solid line in FIG. 1 is the light ray to be irradiated, and the dotted line is the reflected light from the fundus Er.

The reflected light from the fundus Er returns to the objective lens 1 again.
The light that has passed through the hole of the perforated total reflection mirror 10 through the half mirror 13 through the focusing lens 11 and the imaging lens 12, is imaged on the solid-state image sensor 14, and is reflected by the half mirror 13. Is reflected by the total reflection mirror 15 and observed by the examiner S by the eyepiece lens 16.

The examiner S observes the lens driving unit 17 while observing.
The focusing lens 11 fixed to the gears 18 and 19 is moved by, and focusing is performed according to the diopter of the eye to be inspected. The lens driving unit 17 can be configured by using various conventionally known lens interlocking mechanisms such as a heicoid, a link mechanism, and the like.

In this embodiment, the diaphragm 7 fixed to the gears 20 and 21 is linked with the fundus Er of the eye E to be inspected by the lens driving unit 17 during the focusing operation. It has become.

For this reason, the diaphragm 7 is automatically controlled to a position conjugate with the fundus in conjunction with focusing adjustment according to the diopter of the subject, and the range for illuminating the fundus is automatically set to an appropriate range. Therefore, the subject is not dazzled as in the conventional case.

According to this embodiment, the number of operating systems is exactly the same as that of the conventional device, and it is not necessary to pay attention to the operation of the diaphragm 7, and the device can be operated by a simple operation.

[0022]

As is apparent from the above, according to the present invention, in the ophthalmologic measuring device for performing the fundus examination by illuminating the fundus of the eye to be examined, receiving the reflected light and evaluating the fundus image, An illumination optical system equipped with a light source for illuminating the fundus of the eye and an aperture for limiting the illumination light at a position substantially conjugate with the fundus, and the reflected light from the fundus is received to form an image on an imaging plane for photographing or observation. In doing so, a configuration is provided that includes means for focusing according to the diopter of the eye to be inspected and interlocking means for moving the fundus of the eye to be inspected and the diaphragm in a conjugate relationship according to the focusing. Therefore, the examiner can automatically control the diaphragm provided in the illumination optical system to a position conjugate with the fundus of the eye to be inspected by focusing according to the diopter of the eye to be inspected. , With the same number of operations as a normal fundus camera, Enables observation or photographing to the easy, there is excellent effect of reducing the glare of the subject.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a configuration of an ophthalmologic measuring apparatus adopting the present invention.

[Explanation of symbols]

 1 Objective Lens 3 Relay Lens 4 Ring Slit 5 Total Reflection Mirror 6 Relay Lens 8 Condenser Lens 9 Halogen Lamp 10 Perforated Total Reflection Mirror 11 Focusing Lens 12 Imaging Lens 13 Half Mirror 15 Total Reflection Mirror 16 Eyepiece 20 Gear 21 Gear

Claims (1)

[Claims] 1. A light source for illuminating a fundus of an eye to be examined and an illuminating light are limited in an ophthalmologic measuring apparatus for performing a fundus examination by illuminating a fundus of the eye to be inspected and receiving reflected light to evaluate a fundus image. An illumination optical system provided with a diaphragm at a position substantially conjugate with the fundus, and when receiving reflected light from the fundus and forming an image on an imaging plane for photographing or observation, focusing according to the diopter of the eye to be examined. And an interlocking unit for moving the fundus of the eye to be inspected and the diaphragm in a conjugate relationship in accordance with the focusing.