JPH07299032A - Optometrical device - Google Patents

Abstract

PURPOSE:To show a target never influenced by switching of long-distance and short-distance viewing inspections, and make an optometrical measurement by the binocular vision having a wide visual field. CONSTITUTION:In a long-distance viewing inspection, the light from a target 4 is reflected by a half mirror 2 and a concave mirror 3 broader than the eye width of a testee, and then again incident to the half mirror 2, and the testee S observes the target 4 by the transmitted light thereby. In a short-distance viewing inspection, the half mirror 2 is rotated by 90 deg. and switched to the position of a half mirror 2', the light from the target 4 is directly reflected by the half mirror 2', and the testee S observes the target 4 by this reflected light. The testee S judges the direction of an optometric mark, whereby the visual acuity is measured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optometer such as a optometer used in an ophthalmological hospital or an eyeglass store.

[0002]

2. Description of the Related Art Conventionally, in an optometry apparatus equipped with an optotype optical system capable of binocular vision, a method of presenting different optotypes to the left and right eyes by different optical systems has been adopted. In addition, a method of presenting a single visual target through separate lenses for the left and right eyes, a method of presenting a single visual target using a single large lens, and the like have been proposed.

[0003]

However, in the method of the above-mentioned conventional example, when observing different targets for the left and right eyes with different optical systems, there is a drawback that the visual field of the eye to be examined cannot be wide. is there. In addition, when using a lens having a diameter smaller than the interpupillary distance, a problem that convergence occurs due to the interpupillary distance of the subject occurs, and a lens having a diameter larger than the interpupillary distance must be used to solve this problem. I won't.

The object of the present invention is to solve the above-mentioned problems,
An object of the present invention is to provide an optometry apparatus for binocular vision having a wide visual field that is not affected by switching between a distance vision test and a near vision test.

[0005]

In order to achieve the above-mentioned object, an optometry apparatus according to a first aspect of the present invention comprises a concave mirror having a lateral diameter larger than the interpupillary distance of an eye to be inspected, and the concave mirror and the eye to be inspected. And an optotype which is reflected by the light splitting member and the concave mirror and further transmitted through the light splitting member to be presented to the subject.

The optometry apparatus according to the second invention is characterized by having a concave mirror having a lateral diameter larger than the interpupillary distance and an optotype which is obliquely reflected by the concave mirror and is presented to the eye to be examined.

[0007]

In the optometry apparatus of the first invention having the above-mentioned structure, a light splitting member is provided between the concave mirror having a lateral diameter larger than the eye width and the eye to be examined, and the light splitting member and the concave mirror are reflected, and The target is presented to the subject through the light splitting member.

Further, the optometry apparatus of the second invention is provided with a concave mirror having a lateral diameter larger than the interpupillary, and presents the visual target to the subject by reflecting the concave mirror obliquely.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail based on the illustrated embodiments. FIG. 1 is a configuration diagram of the first embodiment viewed from the side, FIG.
Is a configuration diagram viewed from above. In FIG. 1, the eye E to be inspected
An opening 1 as shown in FIG. 3 having left and right openings 1R and 1L for the examinee S to look into is provided on the front surface of the opening 1R,
On the optical axis O1 passing near the center of 1L, a concave mirror 3 having a width wider than the distance between the half mirror 2 and the openings 1R, 1L is arranged, and an optical axis O2 perpendicular to the optical axis O1 which is the incident direction of the half mirror 2. The target 4 is arranged on the upper side, and the illumination light source 5 is provided behind it. Further, an illumination light source 6 that illuminates the periphery of the optotype, which is a diffuse reflector, is provided diagonally in front of the optotype 4.

The central portion C of the visual target 4 is a liquid crystal for image display, and as shown in FIG. 4, the computer can turn on / off each element thereof to generate the visual acuity measurement mark M. The part C is illuminated by the illumination light source 5 at the rear and presented to the subject S.

In order to make the apparent size of the target 4 always constant, the distance from the concave mirror 3 to the eye E and the concave mirror 3
The distance from the target to the target 4 is almost the focus position of the concave mirror 3, and the half mirror 2 to the concave mirror 3 and the half mirror 2
The distance from the target to the target 4 is the same, and the half mirror 2 rotates 90 degrees around the rotation axis 2a on the optical axis O1 and can move to the position of the half mirror 2'shown by the dotted line. There is.

The left and right eyes EL and ER's line of sight OL and OR of the subject S are
In particular, at the time of distance inspection, two parallel lines of sight parallel to the optical axis O1 reach the concave mirror 3 via the half mirror 2. Therefore,
The horizontal diameter of the concave mirror 3 needs to be larger than the eye width which is the width of the two lines of sight OL, OR, but the vertical diameter may be small, and the shape of the concave mirror 3 may be substantially rectangular or elliptical. Further, if the opening 1L or the opening 1R of the opening 1 on the front surface of the left eye EL or the right eye ER is sequentially shielded, the inspection for each eye can be performed.

In the case of a distance inspection, when the illumination light source 6 is turned on and the target peripheral portion D of the target 5 is illuminated obliquely from the front, the reflected light flux from the target 4 is reflected by the half mirror 2 and the concave mirror 3. Then, the light flux that has entered the half mirror 2 again and has passed therethrough reaches the subject's eye E, and the subject S observes the optotype 4.
At this time, since the visual target 4 is at the focal position of the concave mirror 3, the visual target 4 is observed at a position farther than it appears.

In the case of near vision inspection, the half mirror 2 is set to 90.
The illumination light source 5 is turned on by rotating it to the position of the half mirror 2 '. The light source 5 illuminates the central portion C of the visual target 4 from behind, and the light flux from the visual acuity measurement mark M is reflected by the half mirror 2 '.
The subject directly observes the optotype 4 because it reflects light and directly reaches the eye E to be inspected. The subject determines the direction of the visual acuity measurement mark M,
This measures visual acuity.

In the case of a near vision inspection, the position of the optotype 4 may be brought closer to the optical axis O1 without rotating the half mirror 2. Further, in order to make the half mirror 2 as small as possible, it is preferable to arrange the half mirror 2 so that the reflection direction thereof is the vertical direction.

As described above, in the present embodiment, the binocular vision inspection is performed, and since the visual target 4 can be shared by the left and right eyes, the visual field can be widened and the distance vision can be provided. convenient. Furthermore, since the visual target 4 is at the focal position of the concave mirror 3, the light flux emitted from one point of the visual target 4 becomes parallel light in front of the eye of the subject S, regardless of the size of the eye width of the subject S. The lines of sight OR and OL of the left and right eyes are always parallel, and similarly it is easy to obtain a distance vision.

It should be noted that the opening 1 having the openings 1R and 1L provided on the front surface of the eye E to be inspected as shown in FIG. 3 is used for positioning an eye when used as an automatic optometer for measuring a face close to the device. However, when used for subjective refraction measurement, it can be omitted because the target is observed using a temporary frame of a horopter or lens.

FIG. 5 shows a second embodiment, and the same reference numerals as those in FIG. 1 indicate the same members. The plane mirror 10 is provided at a position approximately in the center of the distance between the concave mirror 3 and the eye E to be examined shown in the first embodiment, and the plane mirror 10 can be inserted into and removed from the optical path similarly to the second embodiment.

In the case of a distance inspection, as in the first embodiment, the luminous flux from the visual target 4 is reflected by the half mirror 2 and the concave mirror 3 and again passes through the half mirror 2 to reach the eye E to be inspected. The person S observes the optotype 4.

In the case of the near vision inspection, the light flux from the optotype 4 is reflected by the half mirror 2 and the plane mirror 10 inserted in the optical path 01 and then passes through the half mirror 2 to reach the eye E to be inspected. Can also observe the target 4. Also in this case, the plane mirror 1
If the distance from 0 to the concave mirror 3 and the distance from the plane mirror 10 to the subject's eye E are made the same, the apparent size of the optotype 4 at the time of switching from the distance examination to the near examination does not change.

FIG. 6 shows a third embodiment, in which an opening 11 having openings 1R and 1L is provided on the front surface of an eye E to be inspected, and the eye width is defined on the optical axis O3 passing near the center of the openings 1R and 1L. The concave mirror 12 having a large lateral diameter is arranged such that its central optical axis O4 is slightly decentered from the optical axis O3. Also, near the focal point of the concave mirror 12 on the optical axis O5 in the reflection direction of the concave mirror 12,
An optotype 13 is provided. A removable plane mirror 14 is provided near the middle of the eye E to be inspected and the concave mirror 12, and the rotary shaft 14
It is possible to move to a solid line position outside the optical path and a dotted line position inside the optical path around a.

The subject S looks into the openings 1R and 1L and observes the target 13 reflected by the concave mirror 12. In the case of the near vision inspection, the rotary shaft 14a is rotated to insert the plane mirror 14 into the optical path, and the subject S observes the target 13 reflected by the plane mirror 14 and traveling on the optical axis O6.

If the distance from the plane mirror 14 to the subject's eye E and the distance from the plane mirror 14 to the concave mirror 12 are the same, the apparent size of the target 13 does not change. It is not necessary to change the size of the 13 mark.

The eccentric direction of the concave mirror 12 is not the left-right direction,
The vertical direction can reduce the eccentric angle. By making the distance between the concave mirror 12 and the eye E to be inspected and the distance between the concave mirror 12 and the visual target 13 approximately the same and making the angle of eccentricity as small as possible, it is possible to reduce the influence of aberrations that accompany eccentricity. Alternatively, another plane mirror may be arranged at the position of the optotype 13, and the plane mirror may be reflected again to observe the optotype 13.

In this third embodiment, the concave mirror 12
By decentering the optical path 05 from the optical path 04, the target 13 can be arranged near the optical path 04, and the vertical space of the optical system can be reduced.

[0026]

As described above, the optometry apparatus according to the first aspect of the present invention uses a concave mirror having a lateral diameter larger than the interpupillary distance, so that there is no intervention of vergence in far vision regardless of the interpupillary distance. A distant feeling can be obtained. In addition, since a single visual target is observed by binocular vision, a wide field of view can be taken, inspection can be performed with one eye or both eyes, and near vision inspection is possible. It is possible to keep the apparent size of the target unchanged even when is switched.

In addition to the effects described above, the eye examination apparatus according to the second aspect of the present invention reduces the volume of the apparatus by making the lateral width of the concave mirror larger than the eye width and further decentering the optical axis of the concave mirror. be able to.

[Brief description of drawings]

FIG. 1 is a side view of the first embodiment.

FIG. 2 is a configuration diagram viewed from above.

FIG. 3 is a front view of a light shielding plate.

FIG. 4 is a front view of an optotype.

FIG. 5 is a configuration diagram of a second embodiment.

FIG. 6 is a configuration diagram of a third embodiment.

[Explanation of symbols]

 1, 11 Aperture 2 Half mirror 3, 12 Concave mirror 4, 13 Target 5, 6 Light source 10, 14 Plane mirror

Claims (7)

[Claims] 1. A concave mirror having a lateral diameter larger than the eye width of the eye to be inspected, and a light splitting member arranged between the concave mirror and the eye to be inspected.
An optometry apparatus comprising: the light splitting member and a target that is reflected by a concave mirror and is further transmitted through the light splitting member to be presented to a subject. 2. The optometry apparatus according to claim 1, wherein the near vision target is presented by providing rotation means for rotating the light splitting member by 90 degrees. 3. The optometry apparatus according to claim 1, wherein a near target is presented by providing a target moving unit that moves the target in the optical axis direction. 4. The optometry apparatus according to claim 1, further comprising a plane mirror insertion means for inserting a plane mirror between the concave mirror and the light splitting member to present a near vision target. 5. An optometry apparatus comprising: a concave mirror having a lateral diameter larger than an interpupillary distance and an optotype which is obliquely reflected by the concave mirror and is presented to an eye to be examined. 6. The optometry apparatus according to claim 5, wherein a near-sighted target is presented by providing a plane-mirror insertion means for inserting a plane mirror between the concave mirror and the optotype. 7. The optometry apparatus according to claim 5, wherein the concave mirror reflects the target in an oblique direction in a vertical direction.