JPS5839527B2 - Remote optometry device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ophthalmometric apparatus, particularly to a remote ophthalmometric apparatus in which an ophthalmometric chart is projected through a corrective lens, and a subject observes the projected chart image.

The present invention provides a remote optometry device that has a simple structure, is convenient to use, and can directly adjust the lens power. It is characterized by having a rotating disk on which a plurality of types of corrective lenses are arranged at intervals in the circumferential direction.

According to the present invention, since corrective lenses with different power levels can be inserted into the chart projection optical path by rotating the rotating disk, the results of optometry can be obtained as the lens power required for visual acuity correction. .

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, in FIG. 1, a light beam from a light source 1 passes through a condenser lens 2, a chart 4 on a chart board 3, and is projected by a projection lens 5.

The chart board 3 is a disc rotatable around the axis 3a,
A large number of optometry charts 4 are arranged along its circumference, and by rotating the chart board 3, one of the many charts 4 is positioned in the optical path 7 of the projected light beam from the condenser lens 2. be able to.

As shown in FIG. 2, a motor 6 is provided to rotate the chart board 4.

A half mirror 8 is arranged at an angle of 45° behind the projection lens 5, and part of the chart projection light flux from the projection lens 5 is reflected in the right angle direction by this half mirror 8, and the rest is reflected by the half mirror 8. Go straight through.

The projection light beam that has passed through the half mirror 8 travels along the optical path 5a, is reflected by the mirrors 9 and 10, and travels along the optical path 12a parallel to the optical path 5a.

The light beam reflected by the half mirror 8 travels along the optical path 5b, is reflected rearward by the mirror 11 at right angles, and
It travels along an optical path 12b parallel to and spaced apart from optical path 12a.

In this example, the light beam projected through each chart is split into two, but separate chart projection systems may be provided for the left and right eyes.

Each of the optical paths 12a, 12b is provided with a corrective lens insertion device 14, 15, respectively.

These corrective lens insertion devices 14,15 are of the same construction, the details of which are shown in FIG. 2 for the insertion device 15.

That is, the corrective lens insertion device 15 includes a disc 18 that is rotatably supported on a fixed shaft 16 and a disc 20 that is fixed to a rotating shaft 19. A number of different spherical lenses 22 are arranged at intervals in the circumferential direction, and a number of cylindrical lenses 23 are similarly arranged at intervals in the circumferential direction on the disk 20.

As shown in FIG. 4, the disk 18 has a radial slit 2.
3 is formed, and a pin 26 on a drive plate 25 engages with this slit 24 to drive the disk step by step.

In this example, the degree of nearsightedness or farsightedness is determined by the lens 22 on the disc 18, and the drive plate 25 is rotated by a drive motor 27.

The drive shaft 19 fixed to the disk 20 is connected to a drive motor 28
It is rotated by

The lens 23 has a lens frame 23a rotatably mounted on a disk 20, and teeth formed on the outer periphery of the lens frame 23a are gears 2 rotatably provided around a drive shaft 19.
9.

The gear 29 is a small gear 31 driven by a motor 30.
The rotation of the motor 30 causes the lens 23 to mesh with the lens 23.
The cylindrical axis of can be rotated.

As shown in FIG. 2, an astigmatism index projection device 32 is provided on the optical path 7 and behind the chart board 3.

This projection device 32 consists of a rotating member 34 having an index such as a colored portion 33 at one point on the circumference.
4 is driven by a motor 36 via a gear 35.

Therefore, while looking at the index projected on the circumference of the astigmatism chart, the test subject turns the motor 3 until the index comes to the most clearly visible position on the chart.
By rotating 6, the direction of the astigmatic axis can be determined.

Referring to FIG. 1, there are mirrors 3 on the optical paths 12a and 12b.
7a and 37b are diagonally arranged at an angle of 45°, and mirrors 38a and 38b are arranged in the reflection optical path thereof.

Mirrors 37a, 38a and mirror 37b. 38b are each moved in pairs in a direction perpendicular to the optical paths 12a, 12b, for example from a solid line position to a broken line position, so that the distance between the optical paths for the left and right eyes can be adjusted from 11 to 12.

Between the left and right corrective lens insertion devices 14, 15 there is provided a device for inserting an accessory lens into the optical path, such as a crossed cylinder lens used for precise determination of the astigmatism axis direction and degree of astigmatism.

This device consists of an arm 40 supported swingably about a horizontal axis 39 and an attached lens 41 rotatably mounted within the arm 40, and the lens 41 can be rotated as appropriate by a knob 42.

Reference numeral 43 denotes a tightening screw, which allows the arm 40 to be swung to the position shown by the imaginary line in FIG.
2 and 23, and can be fixed in that position with screws 43.

In the present invention, the left and right corrective lens insertion devices 14.
Since the distance between the lenses is always constant, there is an advantage that the attached lens can be shared for the left and right eyes.

In this embodiment, pinhole plates 44a and 44b are provided in front of the eye to be examined so that their positions can be adjusted in the left and right directions in order to facilitate alignment between the optometric chart projection light beam and the eye to be examined. .

Generally, the diameter of the beam of light incident on the subject's eye varies depending on the lens power, but is about 5 mm to 20 mm, and when the diameter becomes as small as about 5 mm, it becomes difficult to properly align the eye with the light beam.

In this example, by using the above-mentioned pinhole plate, the position of the eye to be examined relative to the projection light beam can be easily determined.

Furthermore, as shown in FIG. 6-7, the pinhole plate 44a
, 44b are provided with reference devices 45a, 45b for adjusting the anteroposterior position of the eye to be examined.

This reference device includes a hot section 46 having a reference mark 46a;
By adjusting the forehead rest 49 so that the corneal apex of the eye to be examined 48 matches the visual axis connecting the index 46a and the sight 47, the position of the eye to be examined in the anteroposterior direction can be properly positioned. can be determined.

The pinhole plates 44a and 44b can be flipped up from the solid line position in FIG. 1 to the imaginary line position during eye examination.

The present invention includes a rotating disk in which a large number of lenses are arranged in the circumferential direction as a means for inserting a corrective lens into an optical path for projecting an optometric chart. This has the advantage that the appropriate lens power required for vision correction can be directly adjusted.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an optical system of an optometry apparatus showing an embodiment of the present invention, FIG. 2 is a partially enlarged view showing details thereof, and FIG. 3 is a view taken along the line l-11I in FIG. Figure 4 is IV-I of Figure 2.
FIG. 5 is a view taken along the VV line in FIG. 1, FIG. 6 is a plan view of the alignment pinhole plate, and FIG.
It is a view taken along the line ■-■ in the figure. 1...Light source, 4...Chart, 8...
... Half mirror 14, 15 ... Corrective lens insertion device, 17.18, 20 ... Disc, 2
2,23...Lens.

Claims (1)

[Scope of Claims] 1. A device comprising a pair of chart projection optical paths for left and right eyes, and means for inserting a corrective lens into each of the chart projection optical paths, and configured to observe the projected chart image. In the remote optometry apparatus, the corrective lens insertion means includes a rotating disk on which a plurality of types of corrective lenses are arranged at intervals in the circumferential direction. 2. The optometry device according to item 1 above, wherein lenses having different dioptric powers one step at a time are arranged on the disc in order of dioptric power. 3. In the above item 1, the corrective lens insertion means includes at least one rotating disk having a large number of spherical lenses and at least one rotating disk having a large number of cylindrical lenses, An optometry device equipped with an astigmatism index projection device in the optical path. 4. The optometry apparatus according to item 1, wherein the rotating disk is driven step by step by an electric motor.