JPH0576292B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an eye refractometer that is used in eye hospitals and the like to measure the refractive value of the eye and can perform diopter guidance well. .

[Prior Art] Conventional general eye refractometers are equipped with a diopter guiding means for guiding the eye to be examined to the far point, near point, etc., but the optotype for guiding the diopter is a flat one. Therefore, accommodation of the subject's eye may not be sufficiently guided, and as a result, there is a drawback that refraction measurements at far points and near points cannot necessarily be performed accurately.

[Object of the Invention] The object of the present invention is to improve such conventional drawbacks, to be able to reliably guide the subject's eye to the far point or the near point, and to be able to accurately guide the subject's eye to the far point or the near point. An object of the present invention is to provide an eye refractometer capable of measuring refractive power.

[Summary of the invention] The gist of the present invention for achieving the above object is as follows:
comprising a stereoscopic target for the eye to be examined to gaze at, and a projection optical system that projects the stereoscopic target toward the eye to be examined,
The eye refractometer is characterized in that the optical member of the projection optical system or the stereoscopic target is moved in the optical direction of the projection optical system to adjust the diopter of the stereoscopic target and measure the refractive power.

[Embodiments of the Invention] The present invention will be described in detail based on illustrated embodiments.

FIG. 1 shows an embodiment of an eye refractometer according to the present invention, in which a light splitting member 1, a projection optical system 2, and a stereoscopic target 3 are arranged from the eye E side to be examined. A refractive power measuring section 4 is provided on the side.
The projection optical system 2 is for guiding the eye E to the far point, near point, etc., and the stereoscopic target 3 has an apparent depth of several dayopters, and has a thickness of several mm, for example, as shown in the figure. It is possible to use a transparent plate 5 made of glass or the like having different patterns 6a and 6b on both sides. Further, the refractive power measurement section 4 is a device that projects, for example, near-infrared light onto the fundus of the eye E to be examined, and processes the reflected light photoelectrically to measure refractive power.

FIG. 2 shows the stereoscopic visual target 3 of FIG. 1 viewed from the optical axis direction, and the pattern 6a is provided on the front surface of the transparent plate 5, and the pattern 6b is provided on the rear surface.

With conventional planar optotypes, when the optotype is presented in a position where it appears blurry, the subject's eye E has no idea in which direction it should be adjusted. However, in this embodiment, since the stereoscopic optotype 3 having a three-dimensional structure is used as the optotype that the eye E to be examined looks at, a pattern with depth can be clearly seen, and the direction in which the eye E to be examined should be adjusted becomes clear. . Therefore, when the projection optical system 2 is moved to change the apparent position of the stereoscopic target 3, the eye E can be reliably adjusted by following the diopter. Therefore, the measurement can be reliably performed using the refractive power measuring section 4 at the far point or the near point.

Further, in the embodiment, the projection optical system 2 is moved, but instead of moving the projection optical system 2, the stereoscopic target 3 may be moved.

In the above-described embodiment, two types of patterns 6a and 6b were provided on both sides of the transparent plate 5 as the stereoscopic visual target 3, but other patterns such as a hologram may also be used.

[Effects of the Invention] As explained above, the ocular refractometer according to the present invention has the following effects:
Because it uses a stereoscopic target that has distance in the optical axis direction, the eye to be examined can be reliably guided to the far point or near point, and refractive power can be accurately measured at the far point or near point. .

[Brief explanation of the drawing]

The drawings show an embodiment of the ocular refractometer according to the present invention, and FIG. 1 is an optical layout thereof, and FIG. 2 is a front view of a stereoscopic target. 1 is a light splitting member, 2 is a projection optical system, 3 is a stereoscopic target, 4 is a refractive power measurement unit, 5 is a transparent plate, 6a,
6b is a pattern.

Claims (1)

[Scope of Claims] 1. A stereoscopic visual target for the eye to be examined to gaze at, and a projection optical system that projects the stereoscopic visual target toward the eye to be examined, and an optical member of the projection optical system or the stereoscopic visual target. An eye refractometer, characterized in that the diopter of the stereoscopic target is adjusted by moving it in the optical axis direction of the projection optical system to measure the refractive power. 2. The stereoscopic visual target has different patterns on both sides and is a thick transparent plate.
Ophthalmic refractometer as described in Section.