JPH0575412B2 - - Google Patents

Description

[Detailed description of the invention]

【0001】

[Industrial Application Field] The present invention relates to an eye position testing device,
More specifically, the present invention relates to an apparatus for testing for strabismus or strabismus in an eye to be examined.

【0002】

[Prior Art] Eye position abnormalities can be broadly classified into strabismus and strabismus. Strabismus is classified as an eye position shift that can be recovered by fusional movement, and strabismus is an eye position shift that cannot be recovered by fusional movement. An example of a conventional eye position abnormality testing device is a crosshair target placed at a distance of 5 m or more in the case of a far vision position, or a cross target placed at a distance of 5 m or more in the case of a gaze position.
Using a small lamp, a toy, etc. placed 33 cm away, use a piece of cardboard approximately 5 cm x 15 cm as an obstructor, or in the case of children, a thumb, etc., while having the subject gaze at the above gaze target. This is carried out by observing the displacement of the eye to be examined, more specifically, the displacement of the pupil of the eye to be examined, while inserting and removing the shield in front of the eye to be examined.

[0003] In this test, it is desirable that the examiner be in front of the subject in order to accurately observe the displacement of the pupil of the subject's eye. However, if this is done, the examiner obstructs the subject's field of view, and there is a problem in that the displacement of the pupil of the subject's eye must be observed from the lower front side of the subject's eye. In addition, in this test, it is desirable that the effects of fusion and accommodation of gaze be completely eliminated when the above-mentioned occluder is inserted in front of the subject's eye, and for this purpose, the test must be performed in a completely dark room. , it is necessary that only the gaze target shines and no other objects are visible. However, in reality, this test is performed in a semi-dark room so that the examiner can observe the pupil of the eye to be examined. Therefore, this test has problems in that fusion and accommodation of gaze have not been completely eliminated, and that it is difficult to observe the pupil of the subject's eye due to insufficient brightness of the illumination.

[0004] A large amblyoscope is known as another example of a conventional eye position abnormality inspection device. In this device, although the examiner visually observes the displacement of the eye to be examined, there is a problem in that the eyepiece is placed in front of the eye to be examined, making it difficult to observe the displacement of the eye to be examined. As yet another example of a conventional eye position abnormality testing device, a test eye sector that rotates at high speed with a 90° phase difference is placed in front of the left and right eyes to be tested, while on the screen there is a screen that is similar to the test eye sector. Images are projected by a pair of left and right projectors with synchronized projector sectors, and the image from the right projector is visible only to the right eye, and the image from the left projector is visible only to the left eye. A phase-contrast haploscope is known that is configured to be able to separate Even with this device, although the examiner visually observes the displacement of the eye to be examined, there is a problem in that the sector is placed in front of the eye to be examined, making it difficult to observe the displacement of the eye to be examined.

【0005】

OBJECTS OF THE INVENTION The present invention has been made in view of the above-mentioned problems of conventional eye position abnormality testing devices, and allows the examiner to observe the eye from substantially the surface of the eye without obstructing the examinee's field of view. The purpose of the present invention is to provide an eye position inspection device with high measurement accuracy. Another object of the present invention is to provide an eye position testing device that can accurately test eye position abnormalities by completely eliminating fusion and gaze accommodation of the eye to be examined.

[0006] The present invention further provides an eye position testing device that can easily and accurately observe and measure the displacement of the eye to be examined by forming a bright spot image at the center of the pupil image of the eye to be examined, if desired. The purpose is to A further object of the present invention is to provide an eye position testing device that can accurately test for eye position abnormalities by completely eliminating fusion and gaze adjustment effects even in a bright place if desired.

【0007】

[Structure of the invention] The present invention achieves the above object,
A gaze target projection system for projecting a beam of light from a gaze target toward the subject's eye, an imaging optical system that guides an infrared beam from the anterior segment of the subject's eye to an imaging means, and a display that displays the output of the imaging means. After projecting the gaze target light beam onto both eyes of the subject's eye,
This eye position testing device is characterized in that it is configured to be able to block only the gaze target light beam projected onto one eye.

[0008]

[Embodiments] [First Embodiment] As shown in FIG _.
In the first embodiment, which is configured based on the right eye to be examined optical axis O _L and the right eye to be examined optical axis OR, and is adjusted for distance _eye position examination, the left eye to be examined optical axis O L and the right eye to be examined optical axis _OR are parallel.

[0009] On the left and right eye optical axes O _L , O _R , there are light-emitting gaze target units 1 that can blink independently.
0 and 12 are arranged so as to be able to slide on the optical axis, and the images of the respective gaze targets 14 and 16 are directed to the objective lens, 1
8 and 20 so that the images are focused on the fundus of the left and right eyes L and R to be examined. Gaze target unit 1
Semi-transparent mirrors 22 and 24 that reflect infrared light and transmit visible light are arranged between the mirrors 0 and 12 and the objective lenses 18 and 20.

[0010] Furthermore, it exits from the anterior segment of the eyes L and R, passes through the objective lenses 18 and 20, and passes through the semi-transparent mirror 22,
The infrared light beam reflected by 24 passes through a right angle prism 26
The light beam is refracted so as to travel substantially on the common optical axis 28 by the light beam, and is then imaged onto the infrared imaging tube 32 through the condenser lens 30 . The output signal of the infrared imaging tube 32 is displayed on the CRT 34 as left and right eye images 36, 38. Left and right examined eyes L,
An infrared illumination device 44 including a tungsten lamp 40 and an infrared filter 42 is arranged obliquely in front of R.
The left and right eyes L and R to be examined are illuminated with infrared light.

[0011] The above optical system is placed in one dark box housing 48, and the subject is placed on the optical axis of the left and right eyes.
Openings 50, 5 provided to transmit O _L and O _R
2, gaze at the gaze targets 14, 16. In the above configuration, when the gaze targets 14 and 16 light up, the subject gazes at them, and the gaze targets 14 and 16 turn on.
When the light 6 goes out, the subject cannot see anything, and the subject's eyes L and R are in a state where they are not fusional or fixate. On the other hand, since the eye positions of the eyes L and R to be examined are always displayed on the CRT 34, the gaze targets 14 and 16 are blinked as appropriate, and the CRT at that time is displayed.
It is possible to observe the displacement of the eyes L and R to be examined on 34, and to check for abnormal eye position. for example,
While keeping the gaze target 14 lit, the gaze target 16
When blinking, if the pupil image of the eye R to be examined displayed on the CRT 34 is displaced, the amount and direction of displacement indicate tropism. [Second Embodiment] As shown in FIG. 2, the second embodiment of the present invention is based on the left subject eye L and the left subject eye optical axis O _L and the right subject eye R and the right subject eye optical axis O _R. It consists of
In the second embodiment, which is adjusted for distance eye position testing, the left optical axis O _L of the eye to be examined and the optical axis O _R of the right eye to be examined are parallel.

[0012] Among the configurations of the second embodiment, the same parts as those of the first embodiment are designated by the same reference numerals as those of the first embodiment in the drawings, and the explanation thereof will be omitted. semi-transparent mirror 2
2, 24 and the gaze target units 10, 12, in order from the side of the semi-transparent mirrors 22, 24, the eyes L,
circular aperture stops 100, 102 arranged at positions conjugate with respect to the R pupil position and the objective lenses 18, 20;
A rotary prism 1 arranged at a position conjugate with respect to the subject's glasses wearing position and the objective lenses 18 and 20.
04, 106, relay lenses 108, 110, and infrared reflection, visible light transmission cold filter 11
2,114 are provided.

[0013] In addition, the cold filter 112,1
14 reflection optical axes OR _L and OR _R are equipped with objective lens 1.
8, 20 and relay lenses 108, 110, pinholes 120, 122 for creating a bright spot indicating the center of the pupil of the subject's eye are arranged, and behind the pinholes 120, 122, an infrared LED 124,
126 are arranged. The rotary prisms 104 and 106 rotate the two deflection prisms 130 and 132 in mutually opposite directions around the optical axes O _L and O _R of the eye to be examined, so that the deflection angle of the angle deflection prisms 130 and 132 is changed from 0°. This is to obtain a transmission deviation angle of up to twice that of . Semi-transparent mirror 22,2
The reflection optical axes OK _L and OK _R of No. 4 have objective lenses 18,
circular aperture stop 14 located at 20 focal positions;
0,142 are arranged, and the eyes L and R to be examined are measured with a telecentric optical system, so that accurate eye position observation and measurement is possible even if interpupillary distance adjustment is not accurate. On the optical axis 28 where the reflected optical axes OK _L and OK _R are further reflected by the right angle prism 26 and proceed, there are a field lens 150 and an objective lens 1.
52 are arranged.

[0014] In the above configuration, if the subject's eye is not oblique, the rotary prisms 104, 10
Adjust the transmission declination angle of 6 to 0°. On the CRT34,
When facing forward, the anterior segment of the eye with an infrared bright spot image appearing in the center of the pupil is displayed. If the subject's eye is oblique, the gaze targets 14, 16
While turning off one of the lights and keeping the other one on, the rotary prism 104 or 106 corresponding to the blinking gaze target 14 or 16 is rotated and adjusted so that the corresponding eye L or R will not be displaced by the blinking gaze target. Do it like this. That is, as shown in FIG. 3, the rotary prism 104 or 106 is arranged so that the light flux from the gaze target 10 or 12 and the light flux from the pinhole 120 or 122 enters the eye L or R in the resting position from the front direction. Adjust the rotation.

[0015] At this time, the displacement or non-displacement of the eye L or R to be examined means that, as shown in FIG.
The image of the anterior segment of the subject's eye formed by
or 20, an image is formed on the image pickup tube 32 by the circular aperture stop 140 or 142, the right angle prism 26, the field lens 150, and the objective lens 152, and the judgment is made based on the display on the CRT 34 formed.

[0016] When the subject's eye is in oblique position and no longer moves due to the flashing of the gaze target, the CRT 34 displays an image R' of one subject's eye facing the front, as shown in FIG.
The other eye image L' facing in a direction other than the front is displayed stationary. The transmission polarization angle and direction of the rotary prism 104 or 106 at this time quantitatively represent the oblique position.

【0017】

[Effects of the Invention] Since the present invention is configured as described above, the displacement of the eye to be examined can be observed and measured from the front to the front, and the adjustment effects of fusion and gaze can be completely eliminated. Because you can
It is possible to obtain the effect that an eye position abnormality test can be performed easily and accurately.

[0018] Furthermore, if desired, a bright spot image can be provided at the center of the pupil image of the eye to be examined to facilitate observation and measurement of the displacement of the eye to be examined, and the configuration is such that the examination can be performed in a bright room. It is also possible to obtain the same effect.

[Brief explanation of drawings]

FIG. 1 is an optical diagram of an eye position testing device according to a first embodiment.

FIG. 2 is an optical diagram of an eye position testing device according to a second embodiment.

FIG. 3 is a light flux diagram of the index projection system of the eye position testing device of the second embodiment.

FIG. 4 is a light flux diagram of the observation system of the eye position testing device of the second embodiment.

FIG. 5 is an explanatory diagram of a CRT display using the light beams shown in FIGS. 3 and 4. FIG.

[Explanation of symbols]

L Left eye to be examined R Right eye to be examined 10,12 Gaze target unit 14,16 Gaze target 18,20 Objective lens 22, 24 semi-transparent mirror 26 Right angle prism 32 Infrared image pickup tube 44 Infrared illumination device 100,102 circular aperture diaphragm 104,106 rotary prism 112,114 cold filter 120,122 Pinhole.

Claims (2)

[Claims] 1. A gaze target projection system for projecting a beam of light from a gaze target toward an eye to be examined; an imaging optical system that guides an infrared beam from the anterior segment of the eye to an imaging means; and a display device for displaying the output, and the eye position is configured such that after projecting the gaze target light flux onto both eyes of the subject's eye, only the gaze target light flux projected onto one eye can be blocked. Inspection equipment. Claim 2: The gaze target is two for the left and right eyes.
2. The eye position testing device according to claim 1, wherein the eye position testing device comprises two gaze targets, and is configured such that while one gaze target is turned on, the other gaze target can blink.