JPS62179430A - Eyeground scanning optical 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 [Industrial Field of Application] The present invention relates to a fundus scanning optical device that can be used, for example, as a fundus imaging/photographing device.

[Prior Art] Conventional fundus cameras cannot reduce the pupil diameter beyond a certain level necessary for photographing, and cannot photograph an eye with a cataract.

This is because there is scattering due to opacity in the cornea and crystalline lens, and it is necessary to separate the illuminating light and photographing light in the anterior segment of the eye.

[Objective of the Invention] The object of the present invention is to significantly reduce the pupil diameter required for imaging, to enable fundus imaging and photographing even in patients using miotics, and to enable imaging from areas of the pupil that are less cloudy even in the case of cataracts. An object of the present invention is to provide a fundus scanning optical device.

[Summary of the Invention] The gist of the present invention for achieving the above object is to provide a light source;
It has a two-dimensional scanning optical system, a light splitting member, a small aperture conjugate to the fundus, and a light receiving means, and the light beam emitted from the light source is passed through the light splitting member and the two-dimensional scanning optical system to the subject's eye. The fundus scanning optical device is characterized in that the reflected light from the fundus of the eye to be examined is received by the light receiving means via the two-dimensional scanning optical system, the light splitting member, and the small aperture.

[Embodiments of the invention] The present invention will be explained in detail based on illustrated embodiments.

FIG. 1 shows a configuration diagram of a fundus scanning optical device, in which 1 is a light source that generates a light beam such as a laser, and along the optical path emitted from this light source 1, a focus lens 2 and a focus lens 2 pass the light on one side of the optical axis. A light splitting member 3 that passes through and reflects on the other side, a first relay lens 4, a first light beam scanning member 5 made of, for example, a galvano mirror, a second relay lens 6, and a vertical direction of the first light beam scanning member 5. a second light beam scanning member 7 for scanning the light beam; Objective lenses 8 are sequentially arranged. On the reflection side of the light splitting member 3, a focus lens 9, a condenser lens 10, a pinhole 11 located at the focal plane of the condenser lens 10, and a light receiver 12 made of, for example, a photomultifire are arranged. In addition, pinhole 1
Position 1 is conjugated to the fundus Er, and unnecessary light is cut off.

The laser beam emitted from the light source 1 is transmitted to each optical element 2 to 8.
, enters the eye E to be examined, is reflected by the fundus Er, and enters the optical element 8
4, is reflected by the light splitting member 3, and is imaged on the light receiver 12. Objective lens 8, 1st. The second light beam scanning member 5.7 and the first relay lens 6 constitute a two-dimensional scanning optical system, and the signal from the light receiver 12 is connected to an ordinary fly-in-ge spot imaging device or the like and transmitted to the fundus Er on a CRT. You can get images of.

The pupil Ep of the eye E to be examined is scanned by the first and second light beam scanning members 5.
7. It is optically conjugated to the light splitting member 3. Also,
A similar focus lens 2.9 is used and operates synchronously to adjust the diopter of the eye E to be examined. The light emitted from the light source 8 is parallel light, and only the parallel light of the light beam returned from the focus lens 9 enters the light receiver 12 due to the pinhole 11 placed on the focal plane of the condenser lens IO. .

FIG. 2 shows luminous fluxes L1 and L2 within the eyeball, where the luminous flux Ll is illumination light and hits the cornea Ec and crystalline lens En to generate reflected Φ scattered light. However, since the light receiver 12 only receives light in the same direction as the incident direction, reflections and
The scattered light does not enter the light receiver 12, and the light receiver 12 does not enter the fundus E.
Only the reflected light L2 from r is taken in. Since this relationship holds true regardless of the incident angle, the pupil diameter required for imaging is determined by the diameter of the light beam at the pupil Ep, and can be made significantly smaller. Note that in order to prevent the light reflected by the relay lenses 4 and 6 from entering the light receiver 12, it is preferable that the lenses 4.6 be tilted or eccentric.

FIG. 3 shows another embodiment, in which a focus lens 13, which is the same as the focus lens 2.9 in FIG. 1, is placed in front of the light splitting member 3. In this case, the pupil position may shift slightly, but this is not a major problem.

The light beam scanning member 5.7 may be an acousto-optic element or a polygon mirror, and if the relay lens 6 is a variable magnification system, the imaging angle can be changed. In addition,
The light splitting member 3 can be a mirror with a hole or the like, the light source 1 can be a halogen lamp or the like in addition to a laser, and the pinhole 11 can be a diaphragm made of a small reflective mirror. Furthermore, a photographic film may be used instead of the light receiver 12.

[Effects of the Invention] As explained above, the fundus scanning optical device according to the present invention has the following advantages:
This has the advantage that imaging and photographing can be performed even if the pupil diameter is extremely small. Furthermore, it is not impossible to perform fluorescence fundus imaging using a non-mydriatic method.

[Brief explanation of drawings]

The drawings show an embodiment of the fundus scanning optical device according to the present invention,
FIG. 1 is a diagram of its configuration, FIG. 2 is a diagram of the optical path inside the eyeball, and FIG. 3 is a diagram of the main part of another embodiment. 1 is a light source, 2.9.13 is a focus lens, 3 is a light splitting member, 5.7 is a light beam scanning member, 8 is an objective lens, 10 is a condensing lens, 11 is a pinhole, and 12 is a light receiver. be. Figure 1 Figure 2

Claims (1)

[Scope of Claims] 1. It has a light source, a two-dimensional scanning optical system, a light splitting member, a small aperture conjugate to the fundus, and a light receiving means, and the light beam emitted from the light source is transmitted to the light splitting member. , the light is guided to the eye to be examined via a two-dimensional scanning optical system, and the reflected light from the fundus of the eye to be examined is received by the light receiving means via the two-dimensional scanning optical system, the light splitting member, and the small aperture. Fundus scanning optical device. 2. The two-dimensional scanning optical system includes two sets of light beam scanning members that scan in directions perpendicular to each other.
The fundus scanning optical device described in Section 1.