JPS62101242A - Microscope for operation - 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 [Field of Industrial Application] The present invention relates to a surgical microscope used for corneal surgery and the like.

[Conventional technology]

In recent years, so-called microsurgery, in which microsurgery is performed under magnified observation under a microscope, has become popular, and because it allows the surgery to be performed accurately, it has become popular in various fields, including ophthalmology, neurosurgery, and plastic surgery. has achieved great results.

In addition, especially in the field of ophthalmology, when suturing the colored area during corneal surgery, the radius of curvature of the cornea is measured and the degree of suturing is adjusted according to the measured value, thereby preventing the occurrence of corneal astigmatism after surgery. There is an increasing demand for prevention. In order to meet these demands, for example,
Japanese Patent No. 5436 discloses an example of a surgical microscope equipped with a device that can automatically measure the radius of curvature of the cornea of an eye to be examined. This consists of an observation system for observing the test area,
An observation illumination system that provides illumination for observation, a measurement device that includes a photoelectric detector and a corneal illumination system for measuring the radius of corneal curvature are provided, and light with a predetermined property is removed from the illumination light by the observation illumination system. The present invention is characterized in that it is provided with a removing means for removing the light and a regulating means for regulating the light incident on the photoelectric detector to only light having a predetermined property. Further, the removing means and regulating means are so-called wavelength cut filters that remove and regulate light depending on the wavelength (color) of light.

[Problem that the invention seeks to solve]

As described above, in the conventional technology, in addition to a ring-shaped light source for measuring the radius of corneal curvature, a light source for observing the examination area with a different irradiation angle from the ring-shaped light source is required, so two light sources are installed near the lens barrel of the surgical microscope. It is necessary to provide a different light source, which results in a complicated structure and poor operability, and has drawbacks such as a large loss of illumination light due to the wavelength cut filter. SUMMARY OF THE INVENTION In view of the above points, it is an object of the present invention to provide a surgical microscope in which the vicinity of the lens barrel of the surgical microscope is simple, has good operability, and has efficient illumination.

[Means and effects for solving the problems] The surgical microscope according to the present invention transforms illumination light for corneal curvature radius measurement and corneal observation into linearly polarized light and irradiates it onto the examination area, and the illumination reflected by the cornea Only the polarized light component that is the same as the light is split by a polarization splitting member and guided to the corneal radius of curvature measurement optical system, and a polarized light component that is different from the polarized light component is used as observation light to measure the corneal radius of curvature using the same light source. This enabled the measurement and observation of

〔Example〕

FIG. 1 shows an optical system according to a first embodiment of the present invention.

In the figure, E is the eye to be examined, and C is the cornea of the eye E to be examined.

1 is an illumination light source composed of, for example, a fiber bundle arranged in a ring shape. 2 is a ring-shaped slit, 3 is a ring-shaped collimating lens, and the collimating lens 3 is an annular cylindrical lens that has a refractive index in each meridian direction and has no refractive index in the direction perpendicular to the meridian direction, that is, in the ring circumferential direction. The slit 2 is placed apart from the slit 2 by its focal length, and the image of the slit 2 illuminated by the light tA1 is made parallel to the subject's eye E from an optically infinite distance.
so that it is projected onto the cornea C of the person. Further, the angle formed between the optical axis 0 of the eye E to be examined and the illumination light flux projected onto the eye to be examined is:
The same angle θ is about the optical axis 0. Reference numeral 4 denotes a ring-shaped polarizing plate, which allows only the linearly polarized light perpendicular to the paper surface of the illumination light to be viewed. Don't struggle.

The illumination optical system for the eye E to be examined is configured as described above.

5 is an objective lens of a surgical microscope, and 6.6' is a left and right relay lens, and the optical axes of the relay lenses 6.6' are arranged in parallel. Reference numeral 7.7' denotes left and right eyepieces, which are used to visually observe the images produced by the relay lenses 6 and 6'. The objective lens 5.degree. relay lens 6.6' and the eyepiece lens 7.7' constitute an optical system of a binocular stereomicroscope for three-dimensionally observing the eye E and the cornea C.

8' is a so-called polarizing beam splitter which has the characteristic of reflecting most of the polarized light component perpendicular to the paper surface and transmitting the horizontal polarized light component. 9 is an imaging lens; 10 is a photoelectric converter for two-dimensional imaging; for example, a ccD (Charge Co.
A solid-state imaging element such as an upgraded device is used. Objective lens 5. Relay lens 6', polarizing beam splitter 8', imaging lens 9 and photoelectric converter 10
This constitutes the light receiving section of the corneal radius of curvature measuring device.

Here, the operation of the corneal curvature radius measuring device will be explained.

In FIG. 1, the image of the ring-shaped slit is specularly reflected by the cornea C of the eye E to be examined, forming a reflected image 11 (virtual image). Since this reflected image 11 is an image caused by specular reflection by the cornea C, the linearly polarized light (perpendicular to the plane of the paper) transmitted through the polarizing plate 4 is maintained, and most of it is therefore reflected by the polarizing beam splitter. Therefore, the light receiving section of the corneal radius of curvature measuring device forms a projected image 11' (FIG. 2) onto the photoelectric converter lo. Here, since the cornea C is generally regarded as a toric surface, even if the ring-shaped slit 2 of the illumination optical system is a perfect circle, the corneal reflected image 11 and the projected image 11' on the photoelectric converter 10 are elliptical. Become.

As shown in FIG. 2, there is a projected image 11' projected onto the photoelectric converter lo and three scanning lines 1 at appropriate intervals crossing it.
2, 13. Intersection with the projected image 11 by 14 12', 12
", 13", 13", 14', 14' are found. From the coordinates of five of these intersection points, the elliptical shape of the projected image ll' can be found, and from this the radius of corneal curvature of the eye to be examined is calculated. be able to.

Generally, the equation of an ellipse is ax" + by" +2cxy+dx+ey+1= for any coordinate axes x and y.
It can be written as 0. Here, five of a - e are unknown numbers,
To find this, it is necessary to substitute the coordinates of five points on the plane into the above equation, and three scanning lines are used to find the coordinates of the five points.

Next, an optical system of a binocular stereomicroscope for three-dimensionally observing the eye E and the vicinity of the cornea C will be described.

Except for the linearly polarized illumination light from the illumination optical system and the light specularly reflected by the cornea C, the linearly polarized light is scattered by the eye E and the cornea C, and the linearly polarized light is disturbed and becomes randomly polarized light. ``The images of the eye E and the cornea C created by this randomly polarized light are observed using the optical system of a binocular stereomicroscope.However, the polarizing beam splitter 8' transmits the component of the randomly polarized light that is horizontal to the plane of the paper. Here, 8 may be a polarizing beam splitter that transmits polarized light components horizontal to the plane of the paper and reflects polarized light components perpendicular to the plane of the paper, similar to the polarization beam splitter a'', or a polarized light beam that transmits polarized light components that are horizontal to the plane of the paper. It doesn't matter if it's a board. In addition, in order to increase the separation between the light flux for measuring the radius of curvature of the cornea C, which is linearly polarized light perpendicular to the plane of the paper due to specular reflection on the cornea C, and the observation light, which is randomly polarized light from the eye E and the cornea C, Additionally, a polarizing plate may be inserted closer to the viewer than the polarizing beam splitters 8, 8' and/or between the polarizing beam splitter 8' and the photoelectric detector 10.

Since this embodiment is configured as described above, the radius of corneal curvature can be measured and observed with one light source without the need for two light sources that irradiate at different angles as in the conventional case. The area around the lens barrel of the microscope is simpler and easier to operate. Further, there is no need to provide a wavelength cut filter, and as a result, there is little loss of illumination light, and efficient illumination is possible. Further, by rotating the polarizing plate 4 about the optical axis ◯, the corneal reflection image 11 can be observed at any time. In addition, since the observation and measurement illumination optical axes are coaxial, the ring-shaped light source images formed on the cornea coincide, and also on the photoelectric detector 10, so the observation illumination light affects measurement accuracy. I never give.

FIG. 3 shows an optical system according to a second embodiment of the present invention.

Its configuration is basically the same as that of the first embodiment, but a ring lens 15. A ring strobe 16 is arranged, and the - of the ring strobe 16 is arranged at a position conjugate with the slit 2 with respect to the ring lens 1.5. Here, if the ring strobe 16 is made to emit light only when measuring the radius of curvature of the cornea C, the sensitivity of the photoelectric detection 2g 10 can be lowered than in the first embodiment. Furthermore, if a wavelength cut filter 17 that transmits only near-infrared light is inserted between the ring light source 1 and the ring strobe 16, the visible component of the ring strobe 16 will be visible to the viewer when the ring strobe 16 emits light. As a result, there is no risk of the observer (operator) being dazzled and interrupting the operation. Furthermore, if a wavelength cut filter 18 having the same characteristics as the wavelength cut filter 17 is inserted between the polarization beam splinter 8' and the photoelectric converter 10, stray light from the outside, etc., which may reduce measurement accuracy, can be removed. can be removed.

〔Effect of the invention〕

As explained above, the surgical microscope according to the present invention allows the same illumination light to be incident on the eye to be examined for observation of the eye to be examined and measurement of the radius of corneal curvature, so a separate illumination system can be installed externally. As a result, the structure around the mirror body is simple and easy to operate, and there is no need to provide a wavelength cut filter, resulting in less loss of illumination light and more efficient illumination. be.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the optical system of the first embodiment of the surgical microscope according to the present invention, FIG. 2 is a diagram showing the image formation state on the photoelectric converter of the first embodiment, and FIG. It is a figure showing an optical system of an example. 1...Illumination light source, 2...Slit, 3...
Collimating lens, 4...Polarizing plate, 5...Objective lens, 6.6'...Relay lens, 7.7'...
... Eyepiece, 8.8" ... Polarizing beam splitter, 9. 0. Imaging lens, 1o... Photoelectric converter, 11...
・Reflected image, 11'...Projected image, 12, 13.14.
...Scanning lines, 12', 12', 13', 13', 14
゛, 14'' peak/intersection, E... eye to be examined, C... cornea. Figure 1

Claims (1)

[Claims] A surgical microscope equipped with an observation system for observing an object to be examined and a measuring device for measuring the radius of corneal curvature, an illumination system for observation and measurement, and regulating the illumination light of the illumination system to polarized light. A regulating means for irradiating the area to be examined, and a dividing means for dividing the reflected light from the area to be examined into specularly reflected light and scattered reflected light and guiding the former to the measuring device and the latter to the observation system, respectively, are provided. A surgical microscope characterized by: