JPH0429374B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ophthalmological measuring device used for testing the refractive power and visual acuity of the eye in ophthalmological clinics, opticians, and the like.

Conventionally, this type of device measures visual acuity or refractive power by showing the subject an optotype in the optical system, but the measurer cannot see the pattern on the optotype. In some cases, it was not clear what test was currently being performed, which was extremely inconvenient in terms of operation. In particular, when a large number of patterns are used to make measurements more precise, it becomes increasingly difficult to understand the measurement process, and the problem of the measurement work requiring a lot of effort and time becomes a serious problem.

The purpose of the present invention is to solve the above-mentioned problems.
Make sure that the person taking the measurements knows the pattern being used.
The objective is to provide an ophthalmological measurement device that can improve operability and measurement accuracy, and the gist thereof is to provide an ophthalmological measurement device that is equipped with an anterior segment observation system for the eye to be examined, and by presenting an optotype pattern that is not visually recognized by the examiner to the eye to be examined. In an ophthalmological measuring device for measuring refractive power or visual acuity of an eye to be examined, a pattern generator that produces a display pattern that is the same as or similar to the pattern presented to the eye to be examined, and a pattern created by the pattern generator are provided. It is characterized by having a display device that displays the anterior segment image simultaneously or sequentially.

The present invention will be explained in detail below based on illustrated embodiments.

FIG. 1 shows an embodiment of the present invention,
The eye E to be examined looks at a visual target 4 through an objective lens 1, a half mirror 2, and a relay lens 3. Here, the objective lens 1 and the relay lens 3 constitute a variable diopter optical system, and by moving the relay lens 3 as shown by the arrow, the optotype 4 can be presented in accordance with the diopter of the eye E to be examined. . The optotype 4 may be a conventionally known one, but it may be one in which a large number of liquid crystal elements are arranged so that the direction of the Landolt ring A can be freely changed as shown in FIG. It is desirable to use a liquid crystal optotype B that allows use of only an arbitrary line of an astigmatic optotype as shown in FIG. In addition, a plurality of optotypes 4 having various patterns
may be driven by an electric motor and presented sequentially.

In this embodiment, a display device 6 consisting of a television camera 5 for grasping the external eye portion of the eye E to be examined and a cathode ray tube for displaying an external eye image C photographed by the television camera 5 is provided on the reflective side of the half mirror 2. ing. In addition, a controller 7 having a microprocessor that determines a presentation pattern according to a preset sequence, and a display pattern P similar to the pattern presented by the optotype 4 based on instructions from the controller 7 are created and displayed. A pattern generator 8 for displaying on the device 6 is provided. In this pattern generator 8, a pattern is broken down into picture elements and stored in a recording element such as a PROM. Note that in this case, the display device 6 does not have to be a cathode ray tube, but may be something like a liquid crystal panel.

In the case of this embodiment, an example was shown in which the above-mentioned extraocular image C and display pattern P are displayed simultaneously on the display device 6, but the extraocular image C and the display pattern P are each displayed using the entire surface of the display device 6. It is also possible to display the following information: Furthermore, the extraocular image C and the display pattern P may be displayed simultaneously over the entire surface using separate display devices.

As described above, according to the ophthalmological measuring device according to the present invention, a display pattern similar to the pattern presented to the subject, such as the Landolt ring A shown in FIG. 2 or the liquid crystal optotype B shown in FIG. Since it is displayed on the display device, the person taking the measurement can proceed with the measurement while looking at the displayed pattern along with the external part of the eye to be examined, making it easy to operate and perform efficient measurements in a short time. can. In addition, since the measurement process can be fully understood, it is particularly advantageous when performing precise measurements using a large number of patterns.
It is possible to easily perform highly accurate measurements.
Further, the present invention allows other information such as the current diopter of the presented optotype to be displayed at the same time, compared to methods such as optically projecting the optotype onto an image pickup tube.

[Brief explanation of drawings]

The drawings show an embodiment of the ophthalmological measuring device according to the present invention, and FIG. 1 is a configuration diagram thereof, FIG.
FIG. 3 is a front view illustrating an optotype pattern. 1 is an objective lens, 2 is a half mirror, 3 is a relay lens, 4 is an optotype, 5 is a television camera, 6
is a display device, 7 is a controller, 8 is a pattern generator, C is an extraocular image, and P is a display pattern.

Claims (1)

[Scope of Claims] 1. An ophthalmological measuring device that is equipped with an anterior segment observation system of the eye to be examined and measures the refractive power or visual acuity of the eye to be examined by presenting the eye to the eye with an optotype pattern that is not visually recognized by the examiner. , a pattern generator that creates a display pattern that is the same as or similar to the pattern presented to the eye to be examined; and a display device that displays the anterior segment image simultaneously or sequentially with the pattern created by the pattern generator. An ophthalmological measuring device characterized by having the following. 2. The ophthalmologic measuring device according to claim 1, wherein the display device displays the pattern created by the pattern generator and the anterior segment image separately.