JP2000126129A - Dynamic visual acuity examining device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a measurement possible even when a subject is not good at a switch operation, or has a difficulty to operate the switch, and obtain a measurement result of a high reliability by forming a response inputting means of a sound response means which can respond by sound. SOLUTION: In the case of a subject who is not good at a delicate operation with fingers, or a subject who has handicapped limbs, a response inputting by sound for the distrimination is convenient. For example, a microphone 60 by which the subject responds, and a sound recognizing section 61 which performs the recognition of voice are provided, and a response by sound is made possible by the selection of a selection switch, instead of the inputting of a response signal by a response button 4 or a joy stick 5. In this case, simple words such as 'yes, no, up, down, right, and left' need to be recognized, and a complicated processing means such as a speech recognition software does not need to be provided. The device side performs the same processing as a case wherein a signal by the response button 4 or the joy stick 5 is input, by the input of a response signal by voice, and performs a dynamic visual acuity measurement and the measurement of the reaction period of time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dynamic visual acuity test apparatus for testing a dynamic visual acuity of an eye to be examined.

[0002]

2. Description of the Related Art A dynamic visual acuity inspection device is known as a device for inspecting the appearance (moving visual acuity) of a moving object such as when driving a car. This type of device moves a test target such as a Landolt ring from a distance to a subject's eye at a predetermined speed,
When the subject can read the target, the subject presses a response switch or the like, and the moving body visual acuity is measured based on the target position at that time.

[0003] In addition, this type of apparatus is generally of a manual type in which the examiner determines and inputs the correctness of the discrimination response of the subject's optotype and inputs the same. However, the subject can be discriminated. There has also been proposed an automatic target that responds to the type of the target (the direction of the cut of the Landolt ring) by an operation of tilting the joystick.

[0004]

However, some subjects have no difficulty in driving a car, but are not good at operating fine fingers. In the conventional apparatus, since the calculation is performed from the target position when the response signal is input by operating the response switch or the joystick as described above, in such a person, there remains a problem in the reliability of the obtained measurement result. In some cases, the measurement itself is difficult.

[0005] In view of the above-mentioned drawbacks of the prior art, the present invention makes it possible to obtain a highly reliable measurement result even when the operation of the switch is inadequate or difficult for the subject. It is an object of the present invention to provide a device that can be used.

[0006]

Means for Solving the Problems In order to solve the above problems, the present invention is characterized by having the following configuration.

(1) Moving means for moving the test target toward the eye to be inspected, response input means for responding that the subject can read the test target moved by the moving means, and the response signal In the dynamic visual acuity inspection apparatus that measures the dynamic visual acuity based on the target position when the is input, the response input means is a voice response means capable of responding by voice.

(2) In the dynamic visual acuity test apparatus of (1), the dynamic visual acuity is obtained in consideration of a reaction time from when the subject recognizes the interpretation of the test target to when the subject responds by the voice response means. It is characterized by comprising a calculating means.

(3) In the dynamic visual acuity testing apparatus of (1), a switch responding means for responding that the subject can read the test optotype by operating a switch, and a response input to the voice responding means or the switch. Selecting means for selecting one of the response means.

[0010]

Embodiments of the present invention will be described with reference to the drawings.

<Embodiment 1> FIG. 1 is a diagram showing an appearance of an apparatus according to this embodiment. Reference numeral 1 denotes an apparatus main body, and reference numeral 2 denotes an inspection window through which a subject looks into the apparatus and observes an inspection target presented in a housing by an optical system described later. An operation panel 3 operated by the examiner is arranged on a side surface of the apparatus main body 1.

An operation section operated by a subject is provided integrally with the housing of the apparatus main body 1 on the front side of the lower portion of the apparatus main body 1. Reference numeral 4 denotes a response button to be pressed when a test target presented in a dynamic visual acuity test (in the embodiment, a Landolt ring target is used) is pressed. Stops and disappears. Also, it is used when a visual target cannot be determined during a static visual acuity test. The same response button 4 is provided on the left and right sides of the joystick 5 so that the examiner can respond with a right-handed person, a left-handed person, or the like who can easily operate.

The joystick 5 is used in an automatic test mode in which the test is performed by the subject. By tilting the joystick 5 in the same direction as the direction of the cut of the Landolt ring optotype determined by the subject (tilting in the front, rear, left and right directions), a response can be input. Reference numeral 6 denotes a start button used when the subject starts the test in the automatic test mode, and reference numeral 7 denotes a volume knob for adjusting the volume of the voice guide. The voice of the voice guide is generated by a speaker 9 arranged inside the apparatus main body 1.

Reference numeral 8 denotes a printer that prints out test results. Reference numeral 10 denotes an opening / closing door, in which a speed changeover switch capable of changing an apparent speed of the target is built in, so that the speed can be changed every 20 km / h between 20 km / h and 60 km / h. Has become. It is usually set at 30 km / h.

FIG. 2 is a diagram showing a switch configuration of the operation panel 3. As shown in FIG. Reference numeral 30 denotes a switch for selecting an inspection mode (manual inspection mode, semi-automatic inspection mode, automatic inspection mode);
1 is a switch for selecting an eye to be examined (left, right, both eyes), and 32 is a switch for selecting and starting a static visual acuity test. Reference numeral 33 denotes a visual acuity value switch for selecting a visual acuity value when examining a static visual acuity, and is selectable in 16 steps from a visual acuity value of 0.1 to 1.6. The selected visual acuity value is displayed on the display 33a. 35
Is an optotype switch section, which is provided with four switches for inputting the direction of the cut of the Landolt ring optotype in four directions, up, down, left and right. Further, the type of the presented target can be known by turning on a lamp 35a provided corresponding to the four switches. Reference numeral 36 denotes an input switch for an incorrect answer.

Reference numeral 34 denotes a switch for selecting and starting a dynamic visual acuity test. Reference numeral 37 denotes a display unit having a lamp 37a for displaying the number of tests performed during a dynamic visual acuity test, a display 37b for displaying the visual acuity value, and the like. Reference numeral 38 denotes a print switch. FIG. 3 is a diagram showing main parts of an optical system and a control system of the apparatus. Reference numeral 10 denotes an illumination light source for illuminating a target provided on the target plate 11. On the optotype plate 11, four types of Landolt ring optotypes (having cuts at the top, bottom, left and right) are arranged concentrically, and the optotype is selected by rotating the rotating device 21.

When the illumination light source 10 is turned on, the target on the target plate 11 is illuminated, and the target light flux from the target plate 11 is reflected by the prism 12, passes through the lens group 13, is reflected by the mirror 14, and becomes a lens group. Go to 15. The lens groups 13 and 15 are arranged to form an afocal system, and the distance between the lens groups 13 and 15 is the sum of the focal length of the lens group 13 and the focal length of the lens group 15.

The light beam that has passed through the lens group 15 is
6 is incident. The prism 16 divides the incident light beam into right and left, and reflects the optotype light beam by mirrors 17R and 17L (which are on the back side of the paper surface and is omitted in the drawing) to the right and left eyes of the subject. Make it incident.

Further, the prism 12 is moved by the moving device 22 so that the distance between the subject's eye and the target can be optically changed from 48 m to 3 m. Optotype 1
1 is designed such that the visual acuity value is 1.6 when the distance between the subject's eye and the visual target is 48 m, 1.0 when the distance is 30 m, and 0.1 when the distance is 3 m. Have been.

Reference numeral 18 denotes a protective glass disposed on the inspection window 2, one for each of the right and left mirrors 17R and 17L. Further, when performing the one-eye inspection, a shutter (not shown) is inserted into the optical path before the protective glass 18.

Reference numeral 20 denotes a control unit of the apparatus,
The response button 4 and the joystick 5 are connected.
The control unit 20 controls the lighting of the illumination light source 10 and the operations of the rotation device 21, the movement device 22, and the voice guide generation unit 23 based on the signals input thereto.

When the control unit 20 stops the optotype by inputting a response signal from the response button 4 (or the joystick 5), the position data and the reaction operation loss of the subject stored in the memory 24 are lost. The dynamic visual acuity of the subject is calculated based on the correction data that takes into account the time (loss time required from when the subject recognizes the test target to when the test target is actually stopped).

The calculation of the visual acuity value in consideration of the reaction operation loss time will be described. Generally, there is a time loss in the reaction operation from when the subject recognizes the discrimination of the moving target to when the response button 4 is pressed, and the test target moves forward by the loss time of the reaction operation. are doing. If the moving object visual acuity value corresponding to the target position stopped by the input signal of the response button 4 is directly used as the measurement result, the value will be different from the value at the time when the subject recognizes the discrimination of the target. Therefore, the moving object visual acuity value obtained from the stop position of the optotype is corrected by considering the loss time of the reaction motion of the subject.

In this correction, an average reaction operation loss time obtained statistically is used in this embodiment. The reaction operation loss time used was obtained as follows. The subject presents a Landolt's ring having a visual acuity value that can be easily viewed (for example, a target having a low level of about two steps of static visual acuity obtained in advance or a target 0.1 that can be seen with certainty). The reaction time from the moment of presentation until the subject pressed the response switch was examined.
When presenting the target, the subject was instructed to press the input button as soon as the direction of the cut of the target was known. Also, instead of suddenly brightening the optotype from a dark state, the neglected target chart (with no Landolt ring drawn) of the same brightness as when presenting the optotype is presented from the beginning. The visibility was reduced so as not to affect the detection of the reaction operation loss time. The test was performed by a large number of randomly selected persons regardless of age and gender, performed several times by the same method, and the average was obtained. as a result,
The reaction operation loss time was statistically determined to be about 0.15 seconds. In order to more accurately measure the reaction operation loss time, it is preferable to use the same form (response button or joystick) as the input means used in the dynamic visual acuity device.

A method for calculating a moving object visual acuity value corrected based on the reaction operation loss time obtained in this manner will be described with reference to FIG. The upper part of FIG. 4 shows the apparent distance of the moving optotype, and the lower part shows the moving object visual acuity value (Ki
netic Visual Acuity: hereinafter referred to as KVA value). The KVA value is 1.6 at a target position of 48 m, and 0.1 at a target position of 3 m.
VA value decreases. Here, assuming that the moving speed of the test target is 30 km / h, 4 m from the 48 m point to 3 m is used.
Since it moves in 5.4 seconds between 5 m, it moves in 0.36 seconds in the 0.1 section (3 m) of the KVA value.

The above reaction loss time of 0.15 seconds is converted into a KVA value. Since the target moves in the KVA value of 0.1 section in 0.36 seconds, the reaction loss time of 0.15 seconds corresponds to about 0.04 in KVA value. This means that the KVA value is reduced by 0.04 minutes during the reaction loss time from when the subject recognizes the test target to when the test button is stopped by actually pressing the response button 4. . Therefore, from the KVA value at the time when the response signal is input, the correction data of.
The reaction loss time was offset by adding 04 minutes, KV
A value is obtained.

For example, suppose that the moving target stops at a distance of 34.2 m (point A in FIG. 4), that is, at a KVA value of 1.14 due to the input of the response signal. If this is rounded off as it is to be a display unit step, the KVA value becomes 1.1. By adding a KVA value of 0.04 as correction data to this data, 1.14+
0.04 = 1.18 (point B in FIG. 4). Therefore, the rounded KVA value after correction is improved by one step to 1.2.

When the set speed is changed, 30 km /
h = 0.04 × 20/30 = 0.02 at 20 km / h based on the KVA value of 0.04 which is the correction data at h
7, the correction data is rounded to a KVA value of 0.03. By the same calculation method, 40
0.05 at km / h, 0.07, 6 at 50 km / h
At 0 km / m, 0.08 is used as the correction data.

For example, when the set speed is 60 km / h,
If the point where the test target stops has a KVA value of 0.94, correction data 0.08 may be added to 1.02, and the corrected KVA value of the subject may be rounded to 1.0. .

The above is the method of correcting the KVA value when the test target is stopped between 48 m and 3 m.
Because the travel limit is reached at the point m (KVA value 0.1),
If there is a response input signal after the test target reaches the point 3m, the KVA value is obtained by the following correction method.

FIG. 5 is a diagram showing a correction method after the test target arrives at the point 3 m at the set speed of 30 km / h. Since the KVA value is finally rounded off to the second decimal place and displayed, assuming that the test target can move beyond the 3m point, at the set speed of 30km / h, the CVA point (from the arrival time at the 3m point) 0.18 seconds later)
From point to point D (point 0.18 seconds before the arrival time at point 3m), the KVA value is 0.1.

Therefore, considering the reaction operation loss time, the KVA value of 0.13 seconds from the arrival time at the point 3m to 0.33 seconds obtained by adding the reaction operation loss time 0.15 seconds to 0.18 seconds.
And In other words, after the test target stops at 3m point, 0.3
If a response signal is input within 3 seconds, the KVA value will be 0.1. The measurement of the time from the arrival at the 3 m point may be performed by the control unit 20 from the start of the moving object visual acuity measurement, or may be measured at 3 m.
The timing may be started after the test target reaches the point. If no response signal is input within 0.33 seconds, the KVA value is set to less than 0.1.

The operation of moving visual acuity measurement in the apparatus having the above configuration will be described (the inspection mode is a manual inspection mode).

When the moving object visual acuity switch 34 is pressed, the control unit 20 moves the prism 12 so that the visual target distance becomes 48 m (visual acuity 1.6), and then moves toward the subject's eye at an apparent speed of 30 km / h. Then, the movement of the prism 12 is controlled so that the optotype approaches. The target type is randomly determined by the control unit 20, and the type can be confirmed by turning on the lamp 35a.

The subject presses the response button 4 when the target can be distinguished while observing the incoming target. When the response button 4 is pressed, the control unit 20 immediately sets the prism 1
While stopping the movement of No. 2, the illumination light source 10 is turned off to make the target invisible. At the same time, the control unit 20 calculates the corrected KVA value using the moving object visual acuity value (KVA value) obtained from the apparent position where the target is stopped and the above-described KVA value correction data. Since the KVA value is a value considering the reaction operation loss time, the reliability is higher than the conventional KVA value.

After pressing the response button 4, the subject verbally answers the direction of the cut of the Landolt ring chart. If the target direction answered by the subject matches the target direction in which the selection lamp 35a is lit, the moving object visual acuity switch 34
Press for a second inspection. If the direction of the optotype answered by the subject is different from the direction of the optotype where the selection lamp 35a is lit, it is a wrong answer.
Press 6 to check for incorrect answers. When the wrong answer input switch 36 is pressed, the measurement result at that time is not recorded, and the same inspection is performed again. In this way, only the correct answers are counted, and when a total of five tests are completed, the average KVA value is displayed on the display unit 37, and the dynamic visual acuity test is completed. The inspection result is printed out from the printer 8 by pressing the print switch 38.

In the above KVA value correcting method, the reaction operation loss time is uniformly set to a predetermined time (0 .0) regardless of age and gender.
15 seconds), but for example, correction data of the reaction operation loss time for each age and gender is obtained, and the setting is changed according to the age and gender of each subject, so that KVA can be more accurately performed.
The value can be measured. In this case, data for each age and gender is stored in the memory 24 in advance, and a switch 40 for inputting the age and gender of the operation panel 3 is provided as shown in FIG.

When the switch 40 is pressed once, the age input mode is set, and the age to be input is set by the visual acuity value switch 33. If pressed again, the gender input mode is set in the same way with the eyesight value switch 33. With this setting, the corresponding correction data of the reaction operation loss time is called from the memory 24, and the moving object visual acuity value is corrected.

<Embodiment 2> In the above embodiment, the reaction operation loss time statistically obtained was used as the basis of the correction data. In the second embodiment, however, the reaction operation loss time was determined for each subject before performing the dynamic visual acuity test. By measuring the loss time and using it as correction data, a measurement result can be selected with higher accuracy. The reaction operation loss time measured by another measuring device may be input to the device of the first embodiment. However, since this is troublesome, a mechanism for measuring the reaction operation loss time is incorporated in the second embodiment. This is an example of the apparatus.

FIG. 7 is a view showing an operation panel of the apparatus according to the second embodiment, and 50 is a switch for measuring a reaction time.
The other configuration is basically the same as that of the first embodiment (an ignoring chart is added to the optotype plate 11), and a description thereof will be omitted.

Hereinafter, the operation of the device of the second embodiment will be described.
The following description focuses on the differences from the first embodiment (see the flowchart in FIG. 8). Note that each component will be described using the same reference numerals as in the first embodiment.

First, the static visual acuity of the subject is measured. The subject is instructed to look into the inside of the apparatus from the measurement window 2, and an eye to be examined is selected by the switch 31. When the static visual acuity test is selected by the static visual acuity switch 32, the visual acuity value is selected by operating the visual acuity value switch 33, and the direction (type) of the visual target is selected by the four visual target switches of the visual target switch unit 35. The control unit 20 rotates the optotype plate 11 to place the selected optotype on the optical path, and the illumination light source 10
The prism 12 is moved so that the optical distance of the target illuminated by (1) corresponds to the specified visual acuity value.

In this state, the examiner proceeds with the examination while asking the examinee whether the direction of the cut of the optotype can be determined. The test is performed while changing the visual acuity value and the type of the visual target, and if two or more correct answers out of three are obtained with the same visual acuity value visual target, it is determined that the visual acuity exists.

Next, the reaction time measuring switch 50 is pressed to measure the reaction time of the subject. When the switch 50 is pressed, the control unit 20 presents an ignoring target chart (with no Landolt ring drawn) having the same brightness as when presenting the target. This is to reduce the difficulty of seeing the target due to the change in brightness and to prevent the detection of the reaction operation loss time from being affected.

When presenting the test target, the examiner instructs the subject to press the response button 4 as soon as the direction of the cut in the target is known, and then measures the reaction operation loss time. The optotype switch unit 35 is used to select the direction of the optotype and present the optotype to the subject. The selection lamp 35a is turned on for the selected target. The visual acuity value of the presented target is controlled by the control unit 20 so that a visual acuity value two levels lower than the still visual acuity value obtained earlier is presented. In this case, it is sufficient that the test target has a visual acuity value that allows the subject to easily look at the test target. It may be a mark.

The subject discriminates the direction at the moment when the test target is presented, and inputs a response that the discrimination was made with the response button 4. When the response button 4 is pressed, the control unit 20 erases the test target and measures and stores a reaction time from when the test target is presented to when the response button is pressed (until a response signal is input).

After pressing the response button 4, the subject verbally answers the direction of the Landolt's ring mark. When the subject's answer is correct, the switch 50 is pressed to perform the second examination. When the subject's answer is a wrong answer, the wrong answer input switch 36 is pressed. When the wrong answer input switch 36 is pressed, the measurement result at that time is not recorded, and the same measurement is performed again. In this manner, only correct answers are counted, and when a total of five measurements are completed, an average reaction operation loss time is calculated and displayed using the display units 33a and 37b. In this case, the average of five measurements is taken,
An intermediate value may be selected, or an average of three values excluding the upper and lower limits of the inspection value. It is also possible to change the total number at the discretion of the examiner.

After measuring the reaction time, switch 34
Is pressed to perform the above-described dynamic visual acuity measurement. When correcting the KVA value in the moving-object visual acuity measurement, the average reaction operation loss time previously obtained as the correction data is used. The measurement results of the static visual acuity value and the dynamic visual acuity value are printed by the print switch 3.
Pressing 8 prints out the data from the printer 8 together with the measurement result of the reaction time.

As described above, since the reaction time for each subject can be obtained in advance, a more accurate KVA value can be obtained. In addition, since the result of the reaction time is printed out together with the KVA value, further advice can be individually provided in more detail.

For example, in the subjects A and B,
In both cases, the static visual acuity value is 0.8, and the result of the measurement of the reaction time and the result of the KVA value in consideration of the reaction time have the following relationship (the KVA value in both of the conventional measurement methods not considering the reaction time). = 0.4). A subject: Reaction time = 0.05 sec, KVA value taking into account the reaction time = 0.4 B subject: Reaction time = 1.50 sec, KVA value taking into account the reaction time = 0.8

As compared with the static visual acuity, the subject A has a large decrease in the KVA value, and the subject B has a small decrease. Therefore, it is understood that the subject B is better from the viewpoint of the visual function. The reaction time is better for the subject A and slow for the subject B. In driving a car, a series of time is required to judge the information entered from the eyes and operate the limbs, and it cannot be said that the conventional measurement method measures including this reaction time. In other words, it was linked to the wrong result as "decrease of visual acuity".

In the case of the above example, it is understood from the results of the KVA value and the reaction time that the subject A needs to increase the KVA value, and that "it is recommended to increase the static visual acuity by using appropriate glasses or the like". Such advice can be given. On the other hand, since the subject B does not have a bad visual function but does not have a good reaction time, the subject B can give an advice such as "Be prepared to take measures on a daily basis in an emergency." The quality of the reaction time may be determined based on the time statistically obtained. It is effective to obtain the KVA value by the conventional measuring method and print out the combined value in the sense of comprehensive evaluation, or simply obtain the KVA value obtained by the conventional measuring method.
The VA value and the measurement result of the reaction time are displayed on a display,
Just by printing out, effective advice can be provided for each subject. It is also conceivable to display and print out a message based on not only the measured value but also the reaction time and the KVA value.

In Embodiments 1 and 2 described above, the target button is responded to by the operation of the hand using the response button 4 (although the switch operation can be performed by foot).
In the case of a subject who is not good at fine finger operation, or in the case of a subject who has difficulty in limbs themselves, it is convenient to input a discrimination response by voice. For example, as shown in FIG. 9, a microphone 60 for the subject to respond to and a voice recognition unit 6 for recognizing the voice.
1 is provided so that a response can be made by voice instead of inputting a response signal by the response button 4 (or the joystick 5) by selecting the selection switch 62. In this case, "High,
What is necessary is just to be able to recognize words such as "no, no, no, no, no tongue", and there is no need to provide complicated and expensive processing means such as voice recognition software. In response to the input of the response signal by voice, the apparatus performs the same processing as when the signal of the response button 4 (or the joystick 5) is input, and measures the dynamic visual acuity and the reaction time.

[0054]

As described above, according to the present invention,
Even in the case of a subject who is unsatisfactory in the switch operation for the interpretation response or the operation of the subject is difficult, the measurement can be performed and a highly reliable measurement result can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing an appearance of an apparatus.

FIG. 2 is a diagram showing details of an operation panel.

FIG. 3 is a diagram showing an optical system and a control system.

FIG. 4 is a diagram illustrating an apparent distance of a target and a moving object visual acuity value corresponding to each distance.

FIG. 5 is a diagram illustrating a method of correcting a moving object visual acuity value after the test target arrives at a point 3m.

FIG. 6 is a diagram showing details of an operation panel when age data is included in correction data.

FIG. 7 is a diagram showing details of an operation panel when correction data is obtained for each subject.

FIG. 8 is a flowchart showing a flow when measuring a reaction time.

FIG. 9 is a block diagram of a control system when an input mechanism by voice is provided.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Device main body 3 Operation panel 4 Response button 5 Joystick 8 Printer 20 Control part 22 Moving device 40 Switch 50 Reaction time measurement switch 60 Microphone 61 Voice recognition part 62 Selection switch

Claims (3)

[Claims] 1. A moving means for moving a test target toward an eye to be examined, a response input means for responding that a subject can read the test target moved by the moving device, and a response signal comprising: A dynamic visual acuity testing device for measuring a dynamic visual acuity based on a target position when input is provided, wherein said response input means is a voice response means capable of responding by voice. 2. The dynamic visual acuity inspection apparatus according to claim 1,
A moving visual acuity testing apparatus, further comprising calculating means for obtaining a moving visual acuity in consideration of a reaction time from when the subject recognizes the interpretation of the test target to when the subject responds by the voice response means. 3. The dynamic visual acuity inspection apparatus according to claim 1,
The apparatus further includes switch response means for responding that the test target can be read by the operation of the switch by the subject, and selection means for selecting whether the response input is the voice response means or the switch response means. A dynamic visual acuity inspection apparatus, characterized in that: