JPH09122076A - Eye refractivity measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an eye refractivity measuring apparatus which can provide information on an eye to be inspected to perform a test of eyesight for naked eyes efficiently and accurately by arranging a vision value forecasting means for naked eyes to forecast a naked eye vision value based on objective measuring data and an output means of the results of the forecasting. SOLUTION: A control section 30 is arranged to control the operation of the apparatus as a whole containing an objective refractivity measuring system and a target presenting system 31 An input switch 32 provided with a measuring switch, to generate a trigger signal for starting an objective refractivity measurement, a measuring mode changeover switch, a switch to change over a target chart on a target disc plate 21, a memory having information for judging a vision value, a memory 34 to store various data and a display part to display a measuring data or the like is also arranged. In addition, a display circuit 36, a printer 37 and a drive circuit 38 therefor are arranged. Thus, the control section 30 obtains a naked eye vision value forecast of eyes to be inspected based on an objective measuring data.

Description

Detailed Description of the Invention

[0001]

[0001]

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an eye refractive power measuring apparatus for objectively measuring the refractive power of an eye to be examined.

[0003]

[0002]

[0004]

2. Description of the Related Art An eye refractive power measuring device for objectively measuring the refractive power of an eye to be examined is known. Subsequent to this objective measurement, in order to obtain reference information for determining the prescription value, the naked eye is inspected, and when the subject has glasses, the glasses (hereinafter referred to as old glasses) Sometimes the visual acuity is checked based on the data.

[0005]

The visual acuity value of the optotype initially presented at the time of these visual acuity tests is determined by the examiner by predicting an appropriate visual acuity value, relying on information such as the degree of visibility asked to the examinee. .

Therefore, the objective refractive power is first obtained by the eye refractive power measuring device, and the test target initially presented at the time of the naked eye visual acuity test may be determined based on the measured data. . Further, in the visual acuity test using the old spectacles, the lens power of the old spectacles may be measured by a lens meter, and the test target to be presented first may be determined based on the measured data.

[0007]

[0004]

[0008]

However, such determination of the presenting target is largely due to the experience and knowledge of the examiner, and is difficult for an examiner who is unfamiliar with the examination. If you present a target with a visual acuity value that is far from the original naked eye visual acuity value or the visual acuity value of old glasses, you will have to change the presenting visual acuity and confirm the interpretation to the subject many times, and the examination time will be long. There was a chance

In the case of astigmatism or hyperopia, complicated judgment is required, and it is especially difficult for an examiner who is unfamiliar with the examination.

[0010]

In view of the above problems, the present invention provides an eye refractive power measuring device capable of providing information on the eye to be inspected for efficiently and accurately performing the naked eye visual acuity test or the front eyeglass visual acuity test. This is a technical issue.

[0011]

[0006]

[0012]

Means for Solving the Problems In order to solve the above problems, the present invention is characterized by having the following configuration. (1) In an eye-refractive-power measuring device including objective-refractive-power measuring means for objectively measuring the eye-refractive power of an eye to be examined, the objective-measurement data obtained by the objective-refractive-power measuring means is used. The present invention is characterized by comprising a naked eye visual acuity value predicting means for predicting the naked eye visual acuity value based on the output, and an output means for outputting the prediction result by the naked eye visual acuity value predicting means.

[0013]

(2) The eye refractive power measuring device of (1) is further characterized by further comprising display means for displaying the prediction result.

[0014]

(3) The naked eye visual acuity value prediction means of (1) is
It is characterized by having a table of visual acuity values corresponding to spherical powers to be applied when objective measurement data is myopia.

[0015]

(4) The naked eye visual acuity value prediction means of (1) is
It is characterized by having a table corresponding to the age and spherical power of the subject to be applied when the objective measurement data is hyperopia.

[0016]

(5) The naked eye visual acuity value prediction means of (1) is
Furthermore, when the objective data has astigmatism, it is characterized by comprising astigmatism processing means for correcting the naked eye visual acuity value.

[0017]

(6) The eye-refractive-power measuring device according to (1) is characterized by further comprising a transfer means for transferring data to a device capable of presenting a target.

[0018]

(7) In an eye-refractive-power measuring device equipped with an objective refracting power measuring means for objectively measuring the eye-refractive power of an eye to be examined, it is obtained by a lens meter for measuring the power of a spectacle lens or a contact lens. Input means for inputting the old spectacles measurement data, and old spectacles visual acuity for predicting the old spectacles visual acuity value based on the residual frequency obtained from the comparison between the old spectacles measurement data and the objective measurement data. And a value predicting means.

[0019]

(8) The eye refractive power measuring device according to (7) is a naked eye visual acuity value predicting means for predicting a naked eye visual acuity value based on the objective measurement data obtained by the objective refractive power measuring means,
The naked eye visual acuity measuring means for measuring the naked eye visual acuity of the eye to be examined by presenting the test visual target for the visual acuity test, and the actual naked eye visual acuity value obtained by the naked eye visual acuity measuring means and the naked eye visual acuity value predicting means A visual acuity value correcting means for correcting the predicted old eyeglass visual acuity value by the old eyeglass visual acuity value predicting means based on a comparison with the predicted naked eye visual acuity value.

[0020]

(9) The old eyeglasses visual acuity value predicting means of (7) is characterized by having a table of visual acuity values corresponding to spherical powers to be applied when objective measurement data is myopia.

[0021]

(10) The old spectacles visual acuity value predicting means of (7) is characterized by having a table corresponding to the age and spherical power of the subject to be applied when the objective measurement data is hyperopia. .

[0022]

(11) The old-glasses visual acuity value prediction means of (7) is characterized by further comprising astigmatism processing means for correcting the old-glasses visual acuity value when the residual dioptric power has astigmatism.

[0023]

[0017]

[0024]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a layout diagram of an optical system of an automatic eye-refractive-power measuring device according to an embodiment, and the device according to the embodiment has a subjective inspection function. Although the present apparatus includes a known optical system such as an observation system and a sighting system, the description thereof is omitted because it is not directly related to the present invention.

[0025]

(Objective refractive power measuring system) 1 is a pair of measuring light sources having a wavelength in the infrared region, and 2 and 3 are condenser lenses. A measurement target plate 4 moves on the optical axis so as to be arranged at a position conjugate with the fundus of the eye 5 to be inspected. Reference numerals 6 and 7 are objective lenses, and 8 and 9 are beam splitters.

[0026]

Reference numeral 10 is a reflection mirror, and 11 and 12 are relay lenses. Reference numeral 13 denotes a strip-shaped corneal reflection removal mask, which is disposed at a position conjugate with the cornea of the eye 5 to be inspected, and is rotatable about the optical axis. Reference numeral 14 denotes a moving lens that moves together with the measurement target plate 4, and reference numeral 15 denotes an imaging lens. 16
Is a two-divided measuring light receiving element, which rotates around the optical axis in synchronization with the measuring light source 1 and the corneal reflection removal mask 13.

[0027]

The (target presenting system) 17 is a first relay lens that can move on the optical axis, and the spherical refractive power applied to the eye 5 to be inspected is changed by moving the first relay lens.
Reference numerals 18 and 19 are positive cylindrical lenses having the same focal length, both of which are rotatable about the optical axis in the same direction or the opposite direction by the same amount. It should be noted that when a cylindrical component is created by two cylindrical lenses, it is necessary to take the spherical effect into consideration for correction.

[0028]

Reference numeral 20 is a second relay lens. Reference numeral 21 denotes a disc-shaped optotype disc plate, on the same circumference of which a fixation chart for fixing the eye to be examined at the time of objective measurement, a plurality of visual acuity values of 0.1 to 1.0. All visual acuity charts in which a target is drawn on one screen, visual acuity charts in which visual acuity values are drawn individually for each visual acuity value of 0.1 to 1.0, and point cloud charts used for subjective tests, Various inspection targets such as red green chart are drawn. The optotype disc plate 21 is arranged at the focal position of the second relay lens 20, and is rotationally driven by a motor (not shown) to switch and arrange various types of optotypes on the optical path. Reference numeral 22 is a condenser lens, and 23 is an illumination lamp.

[0029]

FIG. 2 is a diagram showing a main part of a control system of the apparatus of the embodiment.

A control unit 30 controls the operation of the entire apparatus including the objective refracting power measurement system and the optotype presenting system. Reference numeral 31 is a measurement switch for issuing a trigger signal for starting the objective refracting power measurement, and 32 is an input switch having a measurement mode changeover switch or a switch for changing over the target chart on the target disc plate 21. Is. Reference numeral 33 is a memory that stores information for determining visual acuity values, which will be described later, and 34 is a memory that stores various data. Reference numeral 35 is a display unit for displaying measurement data and the like, and 36 is a display circuit. Reference numeral 37 is a printer, and 38 is a drive circuit thereof.

[0031]

Reference numeral 39 is an interface circuit for inputting / outputting data, and a lens meter 40 for measuring the refracting power of a spectacle lens or a contact lens is provided through this apparatus and the interface circuit 39. Cable connection so that the measurement data of the lens meter 40 can be transferred and input. Further, the data stored in the memory 34 can be transferred and output to another optometry apparatus or the like via the interface circuit 39.

[0032]

The operation of the apparatus configured as described above will be described. Since this device has a subjective test function, in addition to the objective refractive power measurement mode, the naked eye visual acuity measurement mode, the old spectacle visual acuity measurement mode, and the subjective refraction mode are selected by the measurement mode changeover switch. Although the mode can be switched to the force measurement mode, the operation of performing the objective refractive power measurement first, and then performing naked eye visual acuity measurement and old spectacle visual acuity measurement will be mainly described here.

[0033]

<Measurement of Objective Refractive Power> In the objective refractive power measurement mode, the fixation target of the target disc plate 21 is set on the optical path of the target presentation system. The examiner positions the eye to be inspected at a predetermined position, aligns the eye to be inspected and the device in a predetermined relationship while observing the anterior segment of the eye by an observation system (not shown), and then presses the measurement switch 31 to obtain the objective refractive power. Make a measurement.

[0034]

The infrared light emitted from the measurement light source 1 is condensed near the cornea of the eye 5 to be inspected after passing through the condenser lenses 2 and 3, the measurement target 4, the objective lens 6 and the beam splitter 8. To reach. On the other hand, the light from the illumination lamp 23 passes through the condenser lens 22 and projects the fixation target set in the optical path onto the fundus to fixate the eye to be examined. When the subject's eye 5 is a normal eye, the target image reflected from the fundus is reflected by the mirror 10 via the beam splitters 8 and 9, passes through the relay lenses 11 and 12, and then the imaging lens 1
5 forms an image on the light receiving element 16. When there is a refraction error, the control unit 30 together with the moving lens 14 measures the measurement target 4 based on the light reception signal detected by the light receiving element 16.
Is moved so as to come to a position conjugate with the fundus of the eye 5 to be inspected.

[0035]

Next, the control unit 30 controls the first relay lens 17
Is moved so that the fixation target is located at a position conjugate with the fundus, and then the first relay lens 17 is moved so that the cloud is applied by an appropriate diopter. With the fogging of the eye to be examined, the measuring light source 1, the corneal reflection removing mask 13 and the measuring light receiving element 16 are synchronized and rotated about the optical axis by 180 °. During rotation, it is possible to know the refractive power value of the eye 5 to be inspected for each radial line from the light reception signal from the light receiving element 16, and the control unit 30 performs a predetermined process on the refractive power value for each radial line, SPH (sphere power), C
Objective measurement data of YL (astigmatic power) and AXIS (astigmatic axis angle) are obtained.

[0036]

The control unit 30 obtains the predicted naked-eye visual acuity value of the subject's eye based on the objective measurement data. The means for obtaining the predicted naked-eye visual acuity value classifies the objective measurement value data into the following four types, and according to the visual acuity value table A by the myopia degree shown in FIG. 3A, and the age shown in FIG. This is performed based on the table B of the adjustment value table. These table tables are stored in advance in the memory 33 (in this embodiment, the CYL value is read by minus reading).

[0037]

SPH value of objective measurement is 0 or minus
Then, based on the table A when the CYL value is 0 (only for emmetropia or myopia only ), the predicted naked eye visual acuity value corresponding to the SPH value (myopia power) is obtained.

[0038]

SPH value of objective measurement is 0 or minus
When there is a CYL value (only astigmatism or astigmatism with myopia)
When there is a) The CYL value is set equal to the SPH value, and the predicted naked eye visual acuity value is obtained from the value obtained by adding the CYL value to the SPH value based on Table A.

The predicted naked-eye visual acuity value may be obtained based on Table A from the equivalent spherical surface value obtained by adding half the CYL value to the SPH value. These two methods can be selected in advance according to the examiner's policy.

[0040]

The SPH value of the objective measurement is positive, and CYL
When the value is 0 (only for hyperopia ), the influence of accommodation power is large in the case of hyperopia, so the accommodation power according to age is obtained from the table B. (The age of the subject should be entered after confirming in advance by interview etc.) Input with the switch 32).

The SPH value obtained by objective measurement is subtracted from the accommodation power obtained from the age based on the table B, and when the value is negative, the value corresponding to the insufficient accommodation power is regarded as the nearsightedness degree. A predicted visual acuity value is obtained from table A. When the value obtained by subtracting the SPH value from the accommodation power is 0 or a positive value, the myopia power in the table A is considered to be 0,
The predicted visual acuity value is 1.0.

[0042]

The SPH value of the objective measurement is positive, and CYL
When there is a value (when there is astigmatism due to hyperopia) , if the value obtained by subtracting the SPH value obtained by the objective measurement from the accommodative power calculated from the table based on table B is negative, then that value is the CYL value. The predicted visual acuity value is obtained from the table A based on the value obtained by adding. When the value obtained by subtracting the SPH value from the accommodation power is 0 or positive, the predicted visual acuity value is obtained from the table A based on only the CYL value.

[0043]

The predicted naked-eye visual acuity values obtained from are stored in the memory 34 together with the objective measurement value data. Also,
The display unit 35 displays the measurement result of the objective measurement (and the predicted naked-eye visual acuity value).

[0044]

<Measurement of the naked eye visual acuity> Subsequently, the mode is switched to the naked eye visual acuity measurement mode (switching to this mode is specified before the objective refractive power measurement, and automatically switched after the objective refractive power measurement. Good). When the measurement mode switching signal is output, the control device 30 drives the disc plate motor to rotate the target disc plate 21 and holds the target of the predicted naked eye visual acuity value obtained as described above. A chart for each visual acuity value is set on the optical path as an initial value. The examiner starts the naked eye visual acuity measurement of the eye to be inspected from the state of presenting the target. The subject is asked if the visual target can be read, and based on the response, the visual acuity value up / down switch of the input switch 32 is operated to switch the visual acuity value chart. The naked eye visual acuity value determined by the switch operation (or the mode shift signal) is displayed on the display unit 35 and stored in the memory 34.

[0045]

<Old spectacle visual acuity measurement> After the naked eye visual acuity measurement, if the subject has spectacles (including contact lenses), the old spectacle visual acuity measurement based on the spectacle power measured in advance is performed. .

[0046]

The power of the spectacle lens is obtained as follows. The measurement data of the spectacle lens measured by the lens meter 40 is transferred to the interface circuit 39 by the transfer signal.
Read out from the lens meter 40 via the memory 34
(The data transfer from the lens meter 40 to this apparatus may be done by IC card or manual input).

[0047]

When the switching signal to the old spectacles visual acuity measurement mode is given, thereafter, the control unit 30 moves the first relay lens 17 based on the old spectacles value data, and the cylindrical lens 1
8 and 19 are rotated to adjust and arrange the optical system corresponding to the old spectacle value data.

[0048]

The control unit 30 also controls the optotype disc plate 21.
Is rotated to set the chart for each visual acuity value on the optical path. At this time, the visual acuity value of the chart is determined as follows (see the flowchart in FIG. 4).

[0049]

First, the residual dioptric power is calculated based on the objective measurement data and the old spectacle value data, and the residual dioptric power is used to predict the visual acuity value of the naked eye (similarly to the process of replacing the residual diopter with the objective measurement data) as shown in FIG. The predicted visual acuity value of the old glasses is obtained based on the tables A and B.

[0050]

Next, the actually measured naked eye visual acuity value obtained in the naked eye visual acuity measurement in the previous step is compared with the predicted naked eye visual acuity value, and if they are the same, the predicted visual acuity value obtained from the residual frequency is directly set. The measured visual acuity value
The same applies when there is no data).

[0051]

When the actual naked eye visual acuity value and the predicted naked eye visual acuity value are different from each other, the predicted visual acuity value of the old glasses is likely to be different from the actual old visual acuity value, and therefore the predicted visual acuity value obtained from the residual frequency is corrected. . For example, to simplify the explanation, C
Considering an astigmatism-free eye with a YL value of 0, if the SPH value of the objective measurement value data is -2.00D (diopter) and the SPH value of the old spectacle value data is -1.00D, the residual frequency is-.
It becomes 1.00D. From the table A in FIG. 3A, the predicted visual acuity value of the naked eye is 0.2, and the predicted visual acuity value of the old glasses is 0.6. At this time, the measured naked eye visual acuity value is 0.4.
If it is, the near-sightedness corresponding to this is table A
Since it is -1.50D, the measured value data of-
The difference from −2.00 D −0.50 D is the correction amount. That is, from -1.00D of the residual frequency to -0.50D of the corrected amount.
The corrected residual dioptric power becomes -0.50D when the value is reduced, and the predicted visual acuity value of the front glasses corresponding to this is 0.8 from the table A.
(This is an example in which the actual visual acuity value is higher than the predicted naked eye visual acuity value, but if it is lower than that, correction is similarly applied). In this way, the predicted visual acuity value obtained from the residual dioptric power is corrected to obtain the corrected predicted visual acuity value of the old glasses. When obtaining the corrected predicted visual acuity value, if the corrected residual dioptric power becomes positive, the corrected predicted visual acuity value is set to 1.0. Also,
When the measured naked-eye visual acuity value is 0.1 or less, since there are a plurality of myopic dioptric powers corresponding to the naked-eye visual acuity value in the table A of the example, in this case, the corresponding myopic visual acuity value corresponds to each myopic visual acuity value. Of the frequencies, the one with the smaller absolute value shall be used.

[0052]

When the corrected predicted visual acuity value by the old glasses is obtained, subsequently, this corrected predicted visual acuity value is compared with the actually measured naked eye visual acuity value. If the corrected predicted visual acuity value is lower, the actually measured naked eye visual acuity is obtained. The value is taken as the default visual acuity value, and in other cases, the corrected predicted visual acuity value with old glasses is taken as the default visual acuity value.

[0053]

When the chart for each visual acuity value having the visual acuity value obtained as described above is initially set on the optical path, the examiner determines the visual acuity based on the response of the interpretation by the examinee as in the above-mentioned naked eye visual acuity measurement. Operate the value up / down switch to switch the chart for each visual acuity value to be presented. The determined visual acuity value of the old glasses is displayed on the display unit 35 and stored in the memory 34.

[0054]

The measurement results thus measured are printed out from the printer 37 by pressing the print switch.

[0055]

In the above embodiments, the eye refractive power measuring device having the subjective test function is described as an example, but the present invention can be applied to a device in which the eye refractive power measuring device is combined with the optotype presenting device.
Further, in the case of a device that does not have this function (subjective test function), the predicted naked eye visual acuity value information obtained from the objective measurement data is displayed on the display unit or printed out to notify the examiner (or By transferring the data to another optometry device), the examiner can utilize this information to improve the efficiency of the visual acuity test, such as when performing the temporary frame test. By allowing old eyeglass measurement data by the lens meter to be input to the eye refractive power measurement device as in the embodiment, the device can obtain the predicted visual acuity value by the old eyeglass from the difference from the objective measurement data. Therefore, by notifying the examiner of this as well, the examiner can use this information for the examination.

[0056]

[0046]

[0057]

As described above, the device according to the present invention can obtain the predicted naked eye visual acuity value information and the predicted visual acuity value information of old glasses from the objective measurement data and notify the examiner of the experience. Even a shallow examiner can easily and efficiently perform an unaided visual acuity test and a visual acuity test using old glasses.

Particularly, in the case of an apparatus having a subjective test function of presenting a test target on the eye to be examined, the test is started from the target display of the predicted visual acuity value obtained, so that even an unskilled examiner can perform the test. The inspection can be performed efficiently.

[Brief description of the drawings]

FIG. 1 is a layout diagram of an optical system of an automatic eye refractive power measuring device according to an embodiment.

FIG. 2 is a control diagram of the automatic eye refractive power measuring device according to the embodiment.

FIG. 3 is a table table serving as a criterion for obtaining a predicted visual acuity value.

FIG. 4 is a flow chart diagram for determining the visual acuity value of the initial target when measuring the visual acuity of old glasses.

[Brief description of reference numerals]

 1 light source for measurement 4 target plate for measurement 16 light receiving element for measurement 17 first relay lens 18 cylindrical lens 19 cylindrical lens 21 visual target disc 33 memory 35 display 37 printer 39 interface circuit 40 lens meter

Claims (11)

[Claims] 1. An eye-refractive-power measuring device comprising an objective-refractive-power measuring means for objectively measuring the eye-refractive power of an eye to be examined,
An unaided visual acuity value predicting unit that predicts an unaided visual acuity value based on the objective measurement data obtained by the objective refractive power measurement unit, and an output unit that outputs the prediction result by the unaided visual acuity value prediction unit, An eye-refractive-power measuring device comprising: 2. The eye-refractive-power measuring apparatus according to claim 1, further comprising display means for displaying the prediction result. 3. The eye refractive power measurement device according to claim 1, wherein the naked eye visual acuity value prediction means has a table of visual acuity values corresponding to spherical powers to be applied when objective measurement data is myopia. . 4. The naked eye visual acuity value prediction means according to claim 1, which has a table corresponding to the age and spherical power of the subject to be applied when the objective measurement data is hyperopia. Force measuring device. 5. The eye refractive power measurement device according to claim 1, further comprising astigmatism processing means for correcting the naked eye visual acuity value when the objective data includes astigmatism. 6. The eye-refractive-power measuring device according to claim 1, further comprising: a transfer unit that transfers data to a device capable of presenting an optotype. 7. An eye-refractive-power measuring device equipped with an objective-refractive-power measuring means for objectively measuring the eye-refractive power of an eye to be examined,
Input means for inputting old spectacle measurement data obtained by a lens meter for measuring the power of the spectacle lens or contact lens, and the comparison between the old spectacle measurement data and the objective measurement data are obtained. An eye-refractive-power measuring device, comprising: old eyeglasses visual acuity value prediction means for predicting the old eyeglasses visual acuity value based on the residual dioptric power. 8. The eye refractive power measuring device according to claim 7, wherein the naked eye visual acuity value predicting means predicts a naked eye visual acuity value based on the objective measurement data obtained by the objective refractive power measuring means, and a visual acuity. A naked eye visual acuity measuring means for measuring the naked eye visual acuity of the eye to be examined by presenting an inspection visual target for the examination, a measured naked eye visual acuity value obtained by the naked eye visual acuity measuring means, and a prediction obtained by the naked eye visual acuity value predicting means An eye-refractive-power measuring device comprising: a visual acuity value correcting unit that corrects a predicted old-glasses visual acuity value by the old-glasses visual acuity value prediction unit based on a comparison with the naked eye visual acuity value. 9. The eye-refractive-power measurement according to claim 7, wherein the old-glasses visual acuity value prediction means has a table of visual acuity values corresponding to spherical powers to be applied when objective measurement data is myopia. apparatus. 10. The old spectacles visual acuity value prediction means according to claim 7,
An eye-refractive-power measuring device having a table corresponding to the age and spherical power of a subject to be applied when objective measurement data is hyperopia. 11. The old spectacles visual acuity value prediction means according to claim 7,
Further, the eye refractive power measuring device is provided with an astigmatism processing means for correcting the visual acuity value of the old glasses when the residual dioptric power has astigmatism.