JPS6264333A - Ophthalmic illumination 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 Application Field] The present invention is particularly useful when performing eye treatment or surgery, in which the anterior segment of the eye is illuminated with strong light for a long period of time in combination with a surgical microscope or the like. The present invention relates to an ophthalmological illumination device that is effective in various cases.

[Prior Art] A conventional device of this type will be explained using a surgical microscope shown in FIG. 3 as an example. In this surgical microscope, illumination light from an illumination light source 2 built into the microscope body l illuminates the eye E through a condenser lens 3, an illumination diaphragm 4, a prism 5, a prism lens 6, and an objective lens 7. Objective lens 7, variable magnification lens 8. uf'l lens9. With an observation optical system consisting of an erecting prism 10 and an eyepiece 11,
The eye E to be examined is observed by an examiner E. Here, the illumination diaphragm 4, the focal position F1 of the objective lens 7, and the focal position 12F2 of the eyepiece lens 11 are in a conjugate relationship with each other.

In normal cases, an extremely powerful light source is used as the illumination light source 2 so that the examiner's eye e can see the observation with sufficient brightness even through the observation optical system, and its brightness is on the focal plane of the objective lens 7. It reaches more than 100,000 lux. Since ophthalmic surgery is performed under such conditions, there is a risk that the fundus of the eye may be damaged by the illumination light that passes through the pupil of the eye E to be examined and reaches the fundus. In order to eliminate this danger, a circular light shielding means 4a is provided in the center of the illumination diaphragm.
For example, it is disclosed in Japanese Patent Application Laid-Open No. 111625/1983, when the anterior segment of the eye E is observed, the pupil of the eye E is made to coincide with the image of the light shielding means 4a, and the illumination light is This is designed to prevent light from entering the fundus of the eye through the pupil. However, in this system, since the illumination diaphragm 4 and the light shielding means 4a are conjugate to the focal point 11FI of the objective lens 7, the illumination field becomes donut-shaped, and the central part becomes dark, making it impossible to observe. have.

Fig. 4 shows the observation state of the microscope when an ophthalmic surgery is performed using such a surgical microscope. It shows that there is. In such cases,
If a light shielding means 4a for protecting the fundus of the examinee's eye E is inserted into the illumination optical path, the pupil P will become dark, and the examiner's eye e will have a chistome 1? It is difficult to perform safe and reliable surgery because it is not possible to see what lies ahead. Conversely, if the light shielding means 4a is removed from the optical path in order to observe beyond the chistome 12, there is a risk that the illumination light will enter the fundus of the eye through the pupil P and damage the retina.

[Object of the Invention] An object of the present invention is to eliminate the drawbacks of the conventional example as described above.
It is an object of the present invention to provide a highly safe ophthalmic illumination device that can prevent damage to the fundus of the eye due to illumination light while illuminating the anterior segment of the eye to be examined with sufficient brightness.

[Summary of the Invention] The gist of the present invention to achieve the above-mentioned object is to provide a method for transmitting a light beam in a plane substantially conjugate to the fundus of the eye to be examined in the optical path of an illumination optical system that illuminates the anterior segment of the eye to be examined. This is an ophthalmologic lighting device characterized by comprising means for blocking or reducing light of a part of the ophthalmologic lighting device.

[Embodiments of the Invention] The present invention will be explained in detail based on the embodiments shown in FIGS. 1 and 2.

In FIG. 1, the same reference numerals as in FIG. 3 indicate the same or equivalent members, and since the observation optical system is the same as in FIG. 3, illustration and description thereof will be omitted. In the illumination optical system, illumination aperture 4
is a simple circular diaphragm, and is not provided with the light shielding means 4a as shown in FIG. As a means to do this, an optical trap 13 formed by a light-blocking filter or a neutral density filter using a light absorber or the like is eccentrically placed in the illumination optical path A and placed at a position conjugate with the center of the fundus Er, as shown in FIG. has been done.

Here, the illumination light emitted from the illumination light source 2 passes through the condenser lens 3, the illumination diaphragm 4, the prism 5, the optical trap 13, the prism lens 6, and the objective lens 7, and illuminates the anterior segment of the eye E to be examined.

Assuming that a pre-incision surgery as shown in FIG. 4 is being performed under a surgical microscope, the focal position F of the objective lens 7 is
1 is located near the pupil P of the eye E to be examined.

Since the illumination diaphragm 4 is conjugate with the focal position IFI, the anterior segment of the eye E to be examined is circularly illuminated. light trap 1
3 is arranged conjugately at the center of the fundus Er of the eye E, so the shadow B of the light trap 13 is projected onto the retina of the eye E, which serves to protect the macular region of the fundus E. Incidentally, the eccentricity of the optical trap 13 is due to the eccentricity of the optical axis of the objective lens 7 and the optical axis of the prism lens 6, and the coaxial illumination of a normal surgical microscope, that is, the observation optical system and the illumination optical system. These are necessary conditions for an illumination device that shares the same objective lens 6.

With this configuration, the illumination light that reaches the fundus ErG is sufficiently blocked or attenuated, and there is little risk that the fundus ErG will be damaged by the illumination light. Since it is non-conjugate with F1, the illumination field can also be illuminated almost uniformly.

Furthermore, if a light trap 13 that completely blocks light is used, the illumination field will also be affected by this and the center will become a little dark, but this is not a problem in practice. However, 1-1, if it is desired to obtain even more uniform illumination, a neutral density filter may be used within a range that allows the amount of light reaching the fundus E' to be safe.

Strictly speaking, the position of the optical trap 13 is determined by moving the observation site on the optical axis and by the degree of refractive error of the eye E.
Although it is no longer conjugate with r, it does not pose much of a practical problem even if it is fixedly placed in the scope of normal anterior segment surgery.However, when removing the crystalline lens in cataract surgery, etc. Considering this, the focal length of the eye E to be examined changes significantly due to crystalline lens extraction, so the optical trap 13
It is safer to make the position movable on the optical axis. In such a case, move the optical trap 13 in the direction of its t1 optical axis! jJl′iT function, but
Since the mechanism becomes increasingly complex, multiple optical traps 13 are required.
It is also possible to prepare an optical trap J3 and insert only the necessary optical trap J3 into the optical path depending on the situation. Regardless of which configuration is adopted, if the optical trap 13 is not needed, it can be retracted from the optical path so that it can be used in the same way as a normal surgical microscope.

Further, in the above-described embodiment, the ophthalmological illumination device is incorporated into a surgical microscope, but it is of course possible to use it in combination with ophthalmological equipment other than the surgical microscope.

[Effects of the Invention] As explained above, the ophthalmic illumination device according to the present invention can sufficiently observe the anterior segment of the eye to be examined under normal uniform illumination, and can reliably prevent damage to the fundus caused by illumination light. This has the advantage of being able to prevent this and ensure high safety.

[Brief explanation of the drawing]

Figures 1 and 2 show an embodiment of the ophthalmic illumination bag 4 according to the present invention, with Figure 1 being an optical layout diagram when it is incorporated into a surgical microscope, and Figure 2 showing the arrangement of a light trap. It is an explanatory diagram,
FIG. 3 is an optical layout diagram of a conventional surgical microscope, and FIG. 4 is an explanatory diagram of the field of view of the microscope during ophthalmic surgery. 1 is the microscope body, 2 is the illumination light source, 4 is the illumination diaphragm, 5
is a prism, 6 is a prism lens, 7 is an objective lens, 1
3 is a light trap.

Claims (1)

[Scope of Claims] 1. A means for blocking or attenuating part of the luminous flux is provided in a plane substantially conjugate to the fundus of the eye to be examined in the optical path of the illumination optical system that illuminates the anterior segment of the eye to be examined. An ophthalmological illumination device characterized by: 2. The ophthalmologic illumination device according to claim 1, wherein the means for blocking or attenuating a portion of the luminous flux is arranged eccentrically from the optical axis. 3. The ophthalmic illumination device according to claim 1, wherein the means for blocking or attenuating a part of the luminous flux is arranged so as to be retractable from the optical path. 4. The ophthalmic illumination device according to claim 1, wherein the means for blocking or attenuating a part of the luminous flux is movable in the optical axis direction in the optical path. 5. A claim in which the means for blocking or attenuating a portion of the light beam comprises a plurality of units arranged at different positions on the optical axis, one of which is selectively inserted into the optical path. The ophthalmological illumination device according to item 1.