JPH0370538A - Self-consciousness type eye examination apparatus - Google Patents

Abstract

PURPOSE:To make it possible to measure accurately a refractive force of a lens spherical surface matching an examined eye without making an apparatus complicate and large by changing continuously a synthesized spherical refractive force of lens means in a field window of view while it is kept uniform based on a relative rotation of two changeable focus lens means. CONSTITUTION:A plurality of lens means 50 and 50 for changing a synthesized refractive force in a field window of view 26 is constituted of two cyclic changeable focus lens means and a synthesized diopter in the field window of view is changed by a relative rotation of disc members 46 and 48 of the lens means. The synthesized diopter can be continuously changed while the synthesized diopter of the lens means in the field window of view is kept uniform in accordance with a relative rotational angle of lens means each other and it is possible to match more accurately the synthesized diopter with an examined eye E without accompanying to make an apparatus complicate and large. Therefore, on the examined eye, it is possible to detect more accurately the diopter of a lens matching the examined eye.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a subjective ophthalmoscopy device for testing the visual acuity of an eye to be examined based on the examinee's awareness, and in particular for testing the spherical refractive power of the eye to be examined more accurately. relates to a technique for improving the accuracy of measuring the spherical refractive power of a lens that is matched to an eye to be examined.

(Background Art) A subjective optometry device is used to test the visual acuity of the subject's eye based on the subject's awareness when producing spectacle lenses or contact lenses. ) measurement function, cylindrical refractive power/axis angle (astigmatism power/astigmatism axis) measurement function, and prism diopter measurement function.

By the way, in such a subjective optometry device, as disclosed in Japanese Patent Application Laid-Open No. 59-44237, etc., a plurality of lens storage cases serving as the main body of the device have a plurality of lenses that can be relatively rotated around the same axis. A lens holding plate is provided, and a number of lenses with different spherical powers are arranged circumferentially at predetermined intervals around the outer periphery of the holding plate so that they can be overlapped with each other within a viewing window formed in a lens storage case. The combination of lenses is successively changed so that the composite spherical refractive power of the lenses superimposed within the visual field matches the eye to be examined, and the spherical refractive power (diobtria) of the lens that matches the eye to be examined can be measured. It was being done.

FIG. 7 shows an example of such a spherical refractive power measurement mechanism, in which 2.4 indicates a lens holding plate connected to a common shaft 6 so as to be relatively rotatable, and S, tO 1 and 2 respectively show lens groups disposed on the outer periphery of the lens holding plate 2.4.

According to such a spherical refractive power measuring mechanism, as disclosed in the above-mentioned publication, while the diopter spacing of one lens group 8 is roughly set, the adjacent diopter spacing of that lens group 8 is set at a constant spacing. By setting the diopter spacing of the other lens group 10 finely in a complementary manner, it is possible to measure the diopter of the lens that matches the eye to be examined at constant intervals within a predetermined range.

However, in the conventional subjective eye examination apparatus using such a spherical refractive power measurement mechanism, as mentioned above, the diopter of the lens to be matched to the eye to be examined can only be measured at preset intervals. Because it is not possible,
There is a problem that a certain amount of error inevitably occurs in the measurement results, and if we try to avoid this problem and suppress the measurement error to a small value, the number of lenses used will inevitably increase, making the optometry device more complex.・There was a problem that it led to larger size.

(Problem to be solved) The present invention has been made against the background of the above, and its object is to solve the problem of the eye to be examined without complicating or increasing the size of the device. It is an object of the present invention to provide a subjective optometry device that can improve the accuracy of measuring the diopters of lenses to be matched.

(Solution Means) In order to solve this problem, in the present invention, the combined refractive power of a plurality of lens means overlapped in the visual field window is changed, and the visual acuity test of the eye to be examined is performed. In a subjective ophthalmoscopy device that performs ophthalmoscopy based on the patient's awareness, two annular variable focus lens means, the first and second, whose spherical refractive power changes continuously at the same rate of change in the circumferential direction, are used as spherical refractive lenses. The plurality of lens means are constructed by overlapping each other so that the directions of increase and decrease of the forces are opposite to each other, and disposing the lens means so as to be relatively rotatable about the same axis so that a part of the overlapping portion is located within the viewing window. , the composite spherical refractive power within the field window is changed by relative rotation of these lens means.

Here, the relative rotation of the first and second variable focus lens means is manually performed, and the rotational position of the lens means is mechanically displayed, and the mechanical display shows the lens means. Although it is possible to know the composite spherical refractive power of detect,
Based on the detection result, a detection means for automatically determining the composite spherical refractive power within the field window of the variable focus lens means is provided, and the composite spherical refractive power within the field window of the lens means is automatically determined. It is preferable to do this in order to improve the operability and handleability of the optometric apparatus. When the relative rotation of the variable focus lens means is automatically performed by the rotation means, it is recommended to relatively rotate the lens means in opposite directions to shorten the measurement time. It is preferable.

The first and second variable focus lens means can each be constructed by combining a plurality of annular lenses, but usually each is constructed from a single lens of the same shape. The Rukoto.

(Function) When a plurality of lenses are superimposed, the combined spherical refractive power (diobtry) of the lenses is the sum of the dioptric powers of the individual lenses, as is well known. Therefore, a plurality of lens means for changing the composite refractive power within the field window is constituted by the two annular variable focus lens means as described above, and the composite diopter within the field window is changed by relative rotation of these lens means. By doing so, the combined dioptre of the lens means within the field window can be maintained uniformly depending on the relative rotational angle between the lens means, or more precisely, according to the relative rotational position of the lens means with respect to the field window. At the same time, it is possible to continuously change the size of the composite diopter of the lens means within the field window, without complicating or increasing the size of the device. It becomes possible to match the lens to the eye to be examined more accurately, and it becomes possible to more accurately detect the diopter of the lens to be matched to the eye to be examined.

In such an apparatus of the present invention, a rotation means is provided to automatically perform relative rotation of both variable focus lens means, and a detection means is provided to detect the diobject from the rotational position of the variable focus lens means. If the dioptre measurement is automatically determined, the operation for measuring the dioptre becomes extremely simple, and if the lens means are rotated in opposite directions, the rate of change of the combined dioptre of both lens means within the field window is This makes it possible to significantly shorten the measurement time. Note that during I adjustment (N), it is desirable to fix one lens means and rotate only the other lens means in order to improve measurement accuracy. Moreover, it is economically desirable that each of the first and second variable focus lens means be composed of a single lens having the same shape.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

First, FIG. 1 shows a front view of an optometry apparatus according to the present invention.
Further, FIG. 2 schematically shows a sectional view taken along the line ■-■ in FIG. 1. In those figures, 20
．． Reference numeral 20 denotes a lens storage case serving as the main body of the apparatus, which is provided corresponding to both the left and right eyes of the subject, and includes a convergence adjustment mechanism and an intermediate tone 1! It is attached to a connecting portion 22 that has a built-in ff mechanism, etc., and is supported by a column (not shown) via a support rod 24 that supports the connecting portion 22.

Each lens storage case 20 is provided with a viewing window 26 located close to each other, and inside each lens storage case 20, a viewing window 26 is provided as in a conventional ordinary optometry device. Within, spherical refractive power (spherical power;
Spherical refractive power measurement mechanism 2 for measuring dioptre)
8. A cylindrical refractive power measuring mechanism 30 for measuring the cylindrical refractive power (astigmatic power) and its axis angle (astigmatic axis), and a prism diopter measuring mechanism 32 for measuring the prism diopter are provided. There is.

Here, the cylindrical refractive power measurement mechanism 30 has the same rotation axis 34.
A plurality of cylindrical lenses 40 are fixed in the circumferential direction on the outer periphery of each of the cylindrical lens holding plates 36 and 38, which are rotatably supported concentrically with each other. The prism diometry measurement mechanism 32 has two rotary prisms 42 and 44 concentrically superimposed on each other so that they can rotate relative to each other. Furthermore, it has a structure similar to that of the conventional device, and among the three types of measuring mechanisms described above, only the spherical refractive power measuring mechanism 28 has a structure different from that of the conventional device. Therefore, in the following, only the structure of the spherical refractive power measurement mechanism 28 for measuring the diopter of the eye E to be examined (more precisely, the diopter of the lens that matches the eye of the examinee) will be described in detail.

That is, FIG. 3 schematically shows the spherical refractive power measuring mechanism 28 of the apparatus of this embodiment. is mainly composed of two disk members 46 and 48 that are rotatably supported by the rotating shaft 34 at the center of each disk.

The two-day disc members 46 and 48 are each made of an optical resin material such as acrylic resin and have the same shape, and the outer peripheral portion corresponding to the viewing window 26 of the lens storage case 20 is annular. The inner portion of the lens portion 50 is a circular holding portion 52, and a gear 54 is integrally provided on each outer peripheral edge.

The gears 54 and 54 of the disk members 46 and 48 are driven to rotate by servo motors (not shown) as rotation means provided corresponding to the gears 54 and 54, respectively.
6.56 are meshed with each other, and thus the disk member 4
6.48 can be rotated independently of each other around the rotation axis 34 by these servo motors.

Here, the lens portions 50° 50 of the disc members 46 and 48 are as follows:
As shown in FIGS. 4 and 5, one surface is a flat surface, while the other surface is a discontinuous point P.
The radius of curvature of the radial section ' R
(R+, Rz) is a curved surface that changes continuously in the circumferential direction, and its radius of curvature: R is continuously changed in the circumferential direction with a predetermined relationship, and It is a variable focus lens in which the diopter (spherical refractive power) changes continuously at the same rate of change over the entire 360° circumferential range.

Here, disk members 46 and 48 having the same shape and having such lens portions 50 are connected to each lens portion 5.
The lens portions 50 . 50 diometry is continuously set in the range of 125D to +25D, and based on the relative rotation of these disk members 46.48, the combined diometry of these lens portions 50.50 within the field window 26 is approximately -50D. It is designed to be uniformly and continuously changed within the range of ~+50D.

Incidentally, FIG. 6 shows the disk member 46 in the device of this embodiment.
Relationship between the diopter value of the lens portion 50 and the angular displacement in the circumferential direction with respect to the discontinuity point P: θ (see Fig. 4) when the lens portion 48 is made of acrylic resin, and the diopter value and the lens portion 50 The radius of curvature 5R (R,
, R, ).

Here, if the amount of change in diopter per unit rotation angle of light is A, diopter: D is calculated as D = A (18
On the other hand, when the refractive index is N, the diopter and the radius of curvature: R have the following relationship, so the radius of curvature: R at the part of the angular displacement: θ is expressed as That will happen.

By the way, in the spherical refractive power measuring mechanism 28 of the device of this embodiment, the lens portion 50 of the disk member 46 and the lens portion 50 of the disk member 48 are symmetrical in the circumferential direction with the viewing window 26 in between. The positional relationship between the disk members 46 and 48 is set as shown in FIG. The disk members 46 and 48 are the rotating shaft 34
They can be rotated relative to each other with the same amount of displacement in opposite directions. Due to such relative rotation of the disc members 46, 48, the disc members 46, 48 are relatively rotated to a position where a viewing table provided at an appropriate distance from the device can be clearly seen through the viewing window 26. , When this is confirmed by the subject and a confirmation signal is issued, the rotational position of the disk member 46, 48 at that time is detected by a rotation sensor (not shown), for example, an encoder provided on a servo motor, and the detection result is On the basis of the,
The diopters of each lens part 50.50 within the field window 26 and thus those lens parts 5 within the field window 26.
A composite diopter of 0.50 is determined in a computer, not shown. Here, the detection means is composed of a computer that calculates the composite diopter and an encoder provided on the servo motor, and as is clear from the above explanation,
Here, one of the lens parts 50.50 of the disc member 46, 48 constitutes the first variable focus lens means, and the other constitutes the second variable focus lens means.

In FIG. 1, reference numeral 60.60 indicates a standard for determining the relative position between the lens storage case 20.20 as the main body of the apparatus and the eye to be examined.

In order to measure the diopter of the lens that matches the eyelid of the subject using such a device, preferably, the discontinuity point P of each lens portion 50, 50 is located at a position opposite to the visual field window 26. In other words, from a state in which the composite diopter of the lens portion 50.50 in the field window 26 is set to 0'', the subject looks into a predetermined visual chart through the field window 26, and then remote control using a computer is performed. By operating each corresponding servo motor, the disk members 46 and 48 are moved to a position where the viewing table can be clearly seen.
Let it rotate. Then, when the viewing table is clearly visible through the viewing window 26, the rotation of the disk members 46, 48 is stopped and a confirmation signal is generated.

In this way, based on the confirmation signal, the rotational position of each disc member 46, 48 is automatically detected by the rotation sensor as described above, and based on the detection result, the rotational position of each disk member 46, 48 is automatically detected in The composite diopter of the lens part 50.50, that is, the diopter of the lens that matches the eye to be examined, is
It is automatically determined by the computer.

Accordingly, in the present embodiment device, when measuring such dioptres, as described above, each disk member 46, 48
The dioptres of the lens portions 50 and 50 of the disk member 46 and 50 change at the same rate of change in the circumferential direction, and the directions of increase and decrease of these dioptres are the same in the circumferential direction for the lens portion 50 of the disc member 46 and the lens portion 50 of the disc member 48. The relative rotation of the disc members 46, 48, which are set opposite in direction, causes the lens portion 50° 50° in the viewing window 26.
Since the composite diopter of the lens portion 50, 50 within the field window 26 is kept uniform while the composite diopter of the lens portion 50, 50 changes continuously, the composite diopter can only be adjusted in steps. Compared to the conventional device, it is possible to match the composite diopter of the lens portion 50,50 within the viewing window 26 to the eye of the subject with extremely high accuracy; therefore, compared to the conventional device,
This makes it possible to significantly improve the accuracy of measuring the diopter of the lens that matches the eye to be examined.

Furthermore, in the device of this embodiment, as described above, the disk members 46, 48 are arranged so that the respective lens portions 50, 50 are symmetrical in the circumferential direction with the viewing window 26 in between, and the viewing window When adjusting the composite dioptre within 26, since the disk members 46 and 48 are relatively rotated in opposite directions with the same amount of displacement (rotation amount), the adjustment is made by the combination of lens portions 50 and 50. This has the advantage that the composite diopter within the viewing window 26 can be changed over the entire range obtained, and the rotation control of the disc members 46, 48 is simple, and the composite diopter within the viewing window 26 can be changed over the entire range obtained. Since the rate of change can be increased, it also has the advantage of requiring less time for measurement.

Although one embodiment of the present invention has been described in detail above, this is a literal illustration, and it goes without saying that the present invention should not be interpreted as being limited to this specific example.

For example, in the embodiment described above, the lens portion 50.50 as a variable focus lens means was integrally formed with the holding portion 52.52 from an optical resin material as a part of the disk member 46.48. It is also possible to configure the portion 50.50 and the holding portion 52.52 separately, and it is also possible to configure the lens portion 50.50 from an optical material other than a resin material.

Further, in the above embodiment, lens portions 50° 50 of the same shape were employed as the first and second variable focus lens means, but the first and second variable focus lens means do not necessarily have the same shape. It is not necessary, and as long as the rate of change of the diopter in the circumferential direction is the same, it is also possible to use lenses with different ranges of diobotomy as the first and second variable focus lens means.

Further, the first and second variable focus lens means each include - lenses (lens portion 50) as in the above embodiment.
Although it is preferable to configure them as follows, each of them may be configured by combining a plurality of annular lenses.

Further, in the embodiment, the lens portion 5'0.50 (rotating member 46.
48) are automatically rotated in opposite directions by a servo motor, but the first and second variable focus lens means are not necessarily rotated only in opposite directions. It is not necessary, they could be made to rotate in the same direction with respect to each other, or it is also possible to have one lens means fixed and only the other lens means rotated. especially,
When finely adjusting the composite diopter, it is preferable to fix one lens means and rotate only the other lens means.

It is also possible to manually rotate the first and second variable focus lens means.

In addition, in the embodiment described above, the present invention is applied to an optometry device that has a spherical refractive power measurement function, a cylindrical refractive power/axis angle measurement function, and a prism diopter measurement function. However, it is also possible to simply apply the present invention to an optometric apparatus having only a spherical refractive power measurement function.

(Effect of the invention) As is clear from the above explanation, according to the device of the present invention,
Based on the relative rotation of the first and second variable focus lens means, the size of the resultant dioptres of the lens means within the field window is continuously adjusted while maintaining the resultant dioptres of the lens means within the field window uniformly. Because it can be changed, there is no need to make the equipment more complicated or larger.
It is possible to match the composite diopter of the lens means within the visual field window to the eye to be examined more accurately than conventional devices, and therefore, the eye to be examined can be matched to that without complicating or increasing the size of the device. This makes it possible to measure lens diopters more accurately than before.

[Brief explanation of drawings]

FIG. 1 is a front view schematically showing an embodiment of the present invention, FIG. 2 is a sectional view taken along the line ■-■ in FIG. 1, and FIG. 3 is a spherical surface of the device shown in FIG. FIG. 4 is a perspective view of a main part of the refractive power measuring mechanism taken out; FIG. 4 is a front view showing a disc member of the spherical refractive power measuring mechanism of the apparatus of FIG.
The figure is a V-■ cross-sectional view in FIG. 4, and FIG.
6 is a graph showing both the relationship between the displacement in the circumferential direction of the lens portion of the disk member of FIG. 5 and the set value of diopters, and the relationship between the diopter value and the radius of curvature of the lens portion. FIG. 7 is a diagram corresponding to FIG. 3 in a conventional optometric apparatus. 20: Lens storage case 26: Viewing window 28: Spherical refractive power measuring mechanism 30: Cylindrical refractive power measuring mechanism 32: Prism diopter measuring mechanism 34: Rotation axis 46.48: Disk member 50: Lens section 52: Holding section 54 □ 56: Gear

Claims (4)

[Claims] (1) In a subjective ophthalmoscopy device that tests the visual acuity of the subject's eye based on the subject's awareness by changing the composite refractive power of a plurality of lens means superimposed within the visual field window, the spherical refractive power in the circumferential direction Two annular variable focus lens means, the first and second annular variable focus lens means in which the spherical refractive power changes continuously at the same rate of change, are overlapped such that the directions of increase and decrease of the spherical refractive power are opposite to each other, and a part of the overlapped portion is The plurality of lens means are arranged so as to be relatively rotatable about the same axis so as to be located within the field window, and the composite spherical refractive power within the field window is changed by the relative rotation of the lens means. A self-aware optometry device characterized by: (2) A rotation means for relatively rotating the first and second variable focus lens means, and a rotational position of the first and second variable focus lens means are detected, and based on the detection results, the variable focus The optometry apparatus according to claim 1, further comprising a detection means for detecting a composite spherical refractive power within the field window of the lens means. (3) The optometry apparatus according to claim (2), wherein the first and second variable focus lens means are relatively rotated in opposite directions by the rotation means. (4) The optometry apparatus according to any one of claims (1) to (3), wherein the first and second variable focus lens means each include a single lens having the same shape.