JPS59155232A - Ophthalmic 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 The present invention relates to an ophthalmological apparatus, particularly an ophthalmological apparatus such as a surgical microscope, which is equipped with a function of measuring eye information such as corneal shape.

Accurately measuring the shape of the corneal surface during corneal surgery is extremely important in order to prevent the occurrence of corneal astigmatism after surgery. There is a strong demand for the practical application of shape measuring devices.

A corneal shape measuring device that is built into a surgical microscope has already been attempted, but it can only be built into a specific surgical microscope, and the measurement optical system is built into the observation optical system of the surgical microscope. Therefore, there were problems such as impairing the observation performance inherent to the surgical microscope.

By the way, it is often convenient to use an eye microscope during surgery, and it is useful to add a corneal shape measurement function to the microscope without impairing the original observation performance.

However, dead space due to parallax in binocular systems is generally not used effectively.

In view of the above, an object of the present invention is to provide an ophthalmologic apparatus that eliminates the drawbacks of the conventional example and effectively utilizes dead space.

The present invention will be explained in detail below with reference to the drawings.

1 to 4 are diagrams of one embodiment of the present invention. In the figure, 1 is a surgical microscope main body, and 2 is an objective lens thereof. Reference numeral 3 denotes a light source consisting of, for example, an annular fluorescent lamp, which illuminates the circular slit projection index 4. The projection index 4 may be a plurality of circular slits arranged in concentric circles, or
It may also be one in which minute light sources such as light emitting diodes are arranged in a circular shape. Alternatively, a method may be used in which the end faces of the optical fiber γ fibers are arranged in a circular shape and the light is illuminated from the other end.

Alternatively, instead of continuous circular indicators, it is also possible to use intermittent indicators or polygonal indicators. When the projection index 4 is projected onto the cornea Ec of the eye to be examined, a corneal reflection image 4' (virtual image) of the projection index 4 is formed by the convex mirror action of the cornea Ec.

The size of this corneal reflection image 4' changes depending on the radius of curvature of the cornea Ec. If the cornea Ec has regular astigmatism, the corneal reflection image 4' will be an ellipse, and if the angle ll@E c has irregular astigmatism, the corneal reflection image 4' will change in size depending on the radius of curvature of the cornea Ec. The reflected image 4' has an irregular shape. Therefore, the surface shape of the cornea EC can be determined by measuring the shape of the corneal reflection image 4'.

An embodiment of the means for measuring the shape of the corneal reflection image 4' will now be described. Reference numeral 5 denotes an optical path changing member, which is a space between the observation optical paths of the binoculars, and has an oblique reflective surface provided outside the observation optical system. This optical path changing member 5 is fixed near the objective lens 2 of the surgical microscope 1 via a microscope housing. The binocular observation light beam of the surgical microscope 1 is not affected by the optical path changing member 5, and the light beam of the measurement optical system for measuring the shape of the corneal reflected image 4' is reflected by the optical path changing member 5. .

The optical path changing member 5 is a relatively small reflecting mirror fixed near the center of the second objective lens, but it may also be a guichroic mirror that wavelength-divides the measurement light flux and the observation light flux. Furthermore, it may be made movable so as not to kick the observation light flux, and any material may be used as long as it does not substantially affect the observation light flux.

Reference numeral 6 denotes an objective lens of the measurement optical system of the corneal shape measuring apparatus, and a diaphragm plate 7 is disposed near the focal position on the rear side, and a polarizing prism 8 is fixed close to the rear side. For example, the aperture plate 7 has a shape with five small hole openings in the center as shown in FIG. 2, and the polarizing prism 8 has five wedge-shaped prism pieces gathered together as shown in FIG. The small hole opening of the aperture plate 7 and the center of the wedge-shaped prism piece of the polarizing prism 8 coincide with each other. The projected light beam of the corneal reflected image 4' that enters the objective lens 6 of the measurement optical system is separated into five light beams through the small hole opening of the diaphragm plate 7 and the polarizing prism 8, which are reflected by the reflecting mirror 9 and sent to each detection element 1. The image is formed on the light-receiving surface of the camera (for example, a -dimensional photodiode array), but the corneal reflection image 4
For example, as shown in FIG. 4, five detection elements 10 are arranged at positions where a projected image 4' of ' is formed. In a corneal shape measuring device having such a configuration, at the time of measurement, a measurement switch (not shown) is turned on and at the same time the corneal reflection image 4 is detected by the detection element.
' is detected, and the detected signal is electrically amplified and calculated by a signal processing circuit (not shown) to determine the major axis, minor axis, and elliptical axis of the ellipse of the corneal reflection image 4', and this elliptical shape is converted. If the cornea has irregular astigmatism and the corneal reflection image does not become a circle or an ellipse, the radius of curvature, degree of astigmatism, and astigmatic axis angle can be calculated and displayed. It is also possible to request and display the information.

Although the measuring device of Naoki's embodiment detects the shape of the corneal reflection image 4' in the five meridian directions, the present invention is not limited to this. A method of rotating the image low cheetah in the measurement optical system may also be used. Alternatively, a two-dimensional image element may be used.

By the way, the object-side focal position of the measurement optical system of the corneal shape measuring device is made to roughly match the object-side focal position of the observation optical system of the surgical microscope, and the optical axis of the measurement optical system is aligned with the surgical microscope 1. By aligning it with the center of the observation field of view, the positioning operation can be performed while observing the corneal reflection image 4' with the surgical microscope l.

In addition, in order to attach this corneal shape measuring device to a surgical IR* mirror, it can be fixed to the lens barrel of the objective lens section of the surgical microscope with screws, or it can be attached using the accessory mounting seat of the surgical microscope, etc. That's fine. In addition, it is preferable to enable attachment to various types of surgical microscopes by simply replacing the attachment fittings.

Furthermore, since the object-side focal position of various types of surgical microscopes differs slightly, it is possible to adjust the object-side focal position of the corneal topography measuring device by using a zoom lens, for example, and also to correct the measurement data. If you set it to
It will also be possible to attach it to surgical microscopes already in use in the field, expanding its range of uses.

FIG. 5 shows another embodiment of the present invention, in which the optical path switching member is made into a concave reflecting mirror, which also serves as the objective lens of the corneal shape measuring optical system.

When observing the surgical microscope, the concave reflector 11 is raised in the optical axis direction so as not to kick the light beam of the observation optical system, as shown by the two-dot chain line in the figure, and when measuring the corneal shape, the measurement switch is turned on. Interlockingly, the concave reflector 11 is rotated about the rotation axis around the zero point to the position indicated by the solid line in the figure, and the corneal reflection image 4' is projected onto the light receiving surface of the detection element of the corneal shape measuring device, and the measurement detection is completed. Then, it can be flipped up again to the position indicated by the two-dot chain line in the figure. This allows the use of a mirror with a relatively large diagonal area, and also allows the observation light flux to escape sufficiently when measurements are not being made.

Alternatively, the concave reflecting mirror 11 may be moved to a position where it does not interfere with the observation light beam of the surgical microscope.

As described above, the corneal shape measuring system of the present invention can be attached to an optical device for ophthalmological observation such as a surgical microscope and used integrally, and constitutes an optical system that measures the corneal shape without going through the internal optical system of the surgical microscope or the like. This allows accurate measurements to be taken without being affected by the internal optical system of a surgical microscope, etc.
Moreover, there is an effect that the observation performance of an optical device for ophthalmological observation such as a surgical microscope is not impaired.

Furthermore, it can be easily attached to and used in various types of optical devices for ophthalmic observation such as surgical microscopes.

Furthermore, an optical path changing member is provided outside the observation optical system in the space between the observation optical paths of binoculars, making effective use of the so-called dead space due to parallax of the binocular system. In addition, by making a mirror with a large diagonal area movable, it can be used, and when not measuring, it can sufficiently escape from the observation light beam, thereby improving the usability of the microscope. Note that in the present invention, the eye information to be examined is not limited to the corneal shape, but may be other information such as eye refractive power.

[Brief explanation of the drawing]

Figure 1 is a sectional view of an embodiment of the present invention, Figure 2 is a diagram of the aperture plate,
3 is a diagram of a polarizing prism, FIG. 4 is an explanatory diagram of the arrangement of a detection element, and FIG. 5 is an explanatory diagram of main parts of another embodiment. In the figure, Ec is the cornea of the eye to be examined, l is a surgical microscope, is the objective lens of the surgical microscope, 3 is the light source, 4 is the projection index, 4'
is a corneal reflection image of a projection index, 5 is an optical path switching member, 6 is an objective lens of the corneal shape measurement optical system, 7 is an aperture plate, 8 is a polarizing prism, 9 is a reflecting mirror, IO is a detection element, and 11 is a concave reflecting mirror. It is.

Claims (1)

[Scope of Claims] 1. In an ophthalmological apparatus having a binocular observation optical system, y, a space between the observation optical paths of the eyes, in which the observation optical path is provided outside the observation optical system without affecting the observation light flux; What is claimed is: 1. An ophthalmological apparatus comprising: an optical path changing means for guiding a light beam from an eye to be examined in a direction different from that of the eye; and a measuring means for measuring information about the eye to be examined using the light beam passing through the optical path changing means. 2. The ophthalmologic apparatus according to claim 1, wherein the optical path changing means is reflective. 3. The ophthalmologic apparatus according to claim 2, wherein the optical path changing means # is a convex mirror. 4. The ophthalmologic apparatus according to claim 2, wherein the reflector # is movable when not measuring. 5. The ophthalmological device according to claim 1, wherein the ophthalmological device # is a binocular m-microscope, and the optical path changing means and the measuring means are attached to a microscope housing.