JP3649921B2 - Dynamic visual acuity testing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a moving body visual acuity inspection apparatus that inspects the moving body visual acuity of an eye to be examined.
[0002]
[Prior art]
2. Description of the Related Art A moving visual acuity inspection device for inspecting the appearance (moving visual acuity) of a moving object when driving a car is known. This type of device moves a test target such as a Landolt ring from a distance toward the subject's eye at a predetermined speed, and when the target is read, the subject presses a response switch or the like. The dynamic visual acuity is measured based on the target position.
[0003]
In addition, this type of device is generally a manual type in which the examiner determines and inputs the correctness / incorrectness with respect to the determination response of the subject's optotype. There has also been proposed an automation system that responds to the type (Landolt ring break direction) by an operation of tilting the joystick.
[0004]
[Problems to be solved by the invention]
Generally, the subject takes some reaction time from recognizing that the target has been discriminated until the response switch or the like is pressed. However, the result of the dynamic visual acuity measurement in the conventional device is calculated as it is from the target position when the response signal of the response switch is input, and the value is expressed as a result of adding the reaction time. Therefore, it was not necessarily accurate as a measurement of dynamic visual acuity.
[0005]
In view of the above-described drawbacks of the prior art, an object of the present invention is to provide a moving object visual acuity inspection device that takes into account the reaction time from when a subject determines a target and responds.
[0006]
Another object of the present invention is to provide a device that can reflect the reaction time of each subject in the measurement result and can give appropriate advice.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the present invention is characterized by having the following configuration.
[0008]
(1) A moving body that has moving means for optically moving an examination target to be presented to the subject's eye toward the subject's eye and measures the moving eyesight of the subject's eye based on the target position when the subject responds In the visual acuity testing device, when the subject reads the test target and responds by the response unit, the target position measuring unit for obtaining the target position at the time of response, and the response unit responds after reading the test target Storage means for storing the reaction time necessary for the calculation, and calculation means for correcting the target position at the time of response based on the reaction time and the moving speed of moving the test target toward the eye to be examined to obtain moving eyesight It is characterized by providing.
[0009]
(2) A moving object that has a moving means for optically moving the test target to be presented to the subject's eye toward the subject's eye and measures the moving eyesight of the subject's eye based on the target position when the subject responds In the visual acuity test apparatus, the subject has a brightness of the target background, and a target position measuring means for obtaining a target position at the time of response when the subject reads the test target and responds by the response means. After showing the target without the target, present the target easily readable to the subject, and measure the reaction time of the subject from the presentation of the target to the response by the response means Reaction time measuring means, and a calculation means for correcting the target position at the time of response based on the reaction time and a moving speed for moving the test target toward the eye to be examined to obtain a moving visual acuity. And
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
[0017]
<Embodiment 1>
FIG. 1 is a view showing the appearance of the apparatus of 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 the housing by an optical system to be described later. An operation panel 3 operated by the examiner is disposed on the side surface of the apparatus main body 1.
[0018]
On the front side of the lower part of the apparatus main body 1, an operation unit operated by the subject is provided integrally with the casing of the apparatus main body 1. Reference numeral 4 is a response button to be pressed when the test target (in the embodiment, the Landolt ring target is used) presented at the time of moving visual acuity test can be determined. When the response button 4 is pressed, the target is displayed at that time. Stops and disappears. Also, it is used when the target cannot be determined during the static visual acuity test. The response buttons 4 are the same on the left and right with the joystick 5 in between, so that the examiner can respond with a right-handed or left-handed one that is easy to operate.
[0019]
The joystick 5 is used in an automatic inspection mode in which the subject himself / herself performs an inspection. A response can be input by tilting the joystick 5 in the same direction as the cut direction of the Landolt target determined by the subject (tilting in the front-rear and left-right directions). Reference numeral 6 denotes a start button used when the subject himself / herself starts an examination in the automatic examination mode. Reference numeral 7 denotes a volume knob for adjusting the volume of the voice guide. The voice of the voice guide is generated by the speaker 9 disposed inside the apparatus main body 1.
[0020]
A printer 8 prints out the inspection result. Reference numeral 100 denotes an opening / closing door, and a speed changeover switch capable of changing the apparent speed of the target is built in the door, so that it can be changed every 10 km / h between 20-60 km / h. It has become. Usually it is set to 30km / h.
[0021]
FIG. 2 is a diagram showing a switch configuration of the operation panel 3. 30 is a switch for selecting an inspection mode (manual inspection mode, semi-automatic inspection mode, automatic inspection mode), 31 is a switch for selecting an eye to be inspected (left, right, both eyes), and 32 is a static visual acuity test. A switch for selecting and starting. Reference numeral 33 denotes a visual acuity value switch for selecting a visual acuity value when examining the static visual acuity, and the visual acuity value 0.1 to 1.6 can be selected in 16 stages. The selected visual acuity value is displayed on the display 33a. Reference numeral 35 denotes a target switch unit, which is provided with four switches for inputting the cut direction of the Landolt ring target in four directions, up, down, left and right. In addition, the type of target presented can be known by lighting a lamp 35a provided corresponding to the four switches. Reference numeral 36 denotes an erroneous answer input switch.
[0022]
Reference numeral 34 denotes a switch for selecting and starting a moving body vision test. Reference numeral 37 denotes a display unit having a lamp 37a for displaying the number of examinations at the time of moving body vision examination, a display 37b for displaying the vision value, and the like. Reference numeral 38 denotes a print switch.
FIG. 3 is a diagram showing the main part of the optical system and 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 target plate 11, four types of Landolt ring targets (having cuts in the upper, lower, left and right directions) are arranged on concentric circles, and the target is selected by the rotation of the rotating device 21.
[0023]
The target on the target plate 11 is illuminated by turning on the illumination light source 10, and the target luminous flux from the target plate 11 is reflected by the prism 12, passes through the lens group 13, reflects off the mirror 14, and travels toward the lens group 15. . The lens groups 13 and 15 are arranged to be an afocal system, and the distance between the lens group 13 and the lens group 15 is the sum of the focal length of the lens group 13 and the focal length of the lens group 15.
[0024]
The light beam that has passed through the lens group 15 enters the prism 16. The prism 16 divides the incident light beam into left and right, respectively, and reflects the target light beam by mirrors 17R and 17L (in the direction of the back side of the paper, not shown in the figure) to the left and right eye of the subject. Make it incident.
[0025]
Further, the prism 12 is moved by the moving device 22 and can optically change the distance between the eye to be examined and the visual target from 48 m to 3 m. The visual target on the visual target plate 11 has a visual acuity value of 1.6 when the distance between the eye to be examined and the visual target is 48 m, a visual acuity value of 1.0 when the distance is 30 m, and a visual acuity value of 0.1 when the distance is 3 m. Designed to be
[0026]
Reference numeral 18 denotes a protective glass disposed in the inspection window 2, and there is one on the left and right according to the mirrors 17R and 17L. Further, when performing a one-eye examination, a shutter (not shown) is inserted on the optical path in front of the protective glass 18.
[0027]
Reference numeral 20 denotes a control unit of the apparatus, to which a panel unit 3, a response button 4, and a joystick 5 are connected. The control unit 20 controls the lighting of the illumination light source 10 and the operation of the rotating device 21, the moving device 22, and the voice guide generating unit 23 by signals input from these.
[0028]
In addition, when the control unit 20 stops the target by inputting a response signal from the response button 4 (or joystick 5), the position data and the reaction operation loss time (subject of the subject) stored in the memory 24 are displayed. The moving visual acuity of the subject is calculated on the basis of correction data that takes into account the loss time required from when the examiner recognizes the test target to when the test target is actually stopped.
[0029]
The calculation of the moving object visual acuity value in consideration of the reaction motion loss time will be described. Generally, there is a time loss in the reaction operation from when the subject recognizes the moving target to the time the response button 4 is pressed, and the test target moves forward by the time of the response operation loss. doing. If the moving object visual acuity value corresponding to the target position stopped by the input signal of the response button 4 is used as the measurement result as it is, it differs from the value at the time when the subject recognizes the determination of the target. Therefore, the moving object visual acuity value obtained from the stop position of the target is corrected by taking into account the loss time of the reaction action of the subject.
[0030]
In this correction, the average reaction operation loss time obtained statistically is used in this embodiment. The reaction operation loss time used was obtained as follows.
Present a Landolt ring with a visual acuity value that makes the subject easy to view (for example, a low visual target of about two steps of static visual acuity obtained by measurement in advance, a 0.1 visual target that can be seen reliably, etc.) The reaction time from the moment of presentation until the subject pressed the response switch was examined. In presenting the target, the subject was instructed to press the input button as soon as the direction of the target cut was known. In addition, the target is not suddenly brightened from the dark state, but by displaying an ignorance target chart (with no Landolt ring) of the same brightness as when the target is presented from the beginning. It is less difficult to see and does not affect the detection of reaction action loss time. The subjects were a large number of people selected at random, regardless of age or gender, and performed several times in the same manner, and the average was obtained. As a result, it was statistically determined that the reaction operation loss time was about 0.15 seconds. In addition, in order to measure the reaction operation loss time more accurately, it is preferable to use the same type (response button or joystick) as the input means used in the moving body vision device.
[0031]
A method of calculating a moving object visual acuity value corrected based on the reaction action loss time obtained in this way will be described with reference to FIG. The upper part of FIG. 4 shows the apparent distance of the moving target, and the lower part shows the dynamic visual acuity value (Kinetic Visual Acuity: hereinafter referred to as KVA value) corresponding to each distance. The KVA value is 1.6 at the target position of 48 m and 0.1 at the target position of 3 m, and the KVA value decreases by 0.1 every 3 m. Here, when the moving speed of the inspection target is 30 km / h, it moves in 45 m from 48 m to 3 m in 5.4 seconds, so the 0.1 section (3 m) of the KVA value is 0.36 seconds. Move with.
[0032]
The reaction loss time of 0.15 seconds is converted into a KVA value. Since the target moves through the 0.1 section of the KVA value in 0.36 seconds, a reaction loss time of 0.15 seconds corresponds to a KVA value of about 0.04. This means that the KVA value is lowered by 0.04 minutes during the reaction loss time from when the subject recognizes the test target to when the test button is actually pressed to stop the test target. . Therefore, a KVA value in which the reaction loss time is offset by adding 0.04 minutes as correction data from the KVA value at the time when the response signal is input is obtained.
[0033]
For example, it is assumed that the moving target is stopped at a distance of 34.2 m (point A in FIG. 4), that is, at a KVA value of 1.14 by inputting a response signal. If this value is rounded off to make it 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 (FIG. 4 point B). Therefore, the rounded KVA value after correction is 1.2, which is one step better.
[0034]
In addition, when the set speed is changed, the correction data is 0.04 × 20/30 = 0.027 at 20 km / h based on the KVA value 0.04 which is correction data at 30 km / h. Rounds off to a KVA value of 0.03. According to a similar calculation method, correction data is 0.05 at 40 km / h, 0.07 at 50 km / h, and 0.08 at 60 km / m.
[0035]
For example, when the set speed is 60 km / h and the point where the inspection target has stopped is a KVA value of 0.94, correction data 0.08 may be added to 1.02, and the corrected subject's The KVA value is rounded to 1.0.
[0036]
The above is a method of correcting the KVA value when the inspection target is stopped between 48 m and 3 m. However, since the inspection target becomes a movement limit at a point of 3 m (KVA value 0.1), the inspection target is When there is a response input signal after reaching 3 m, the KVA value is obtained by the following correction method.
[0037]
FIG. 5 is a diagram showing a correction method after the inspection target arrives at the 3 m point at the set speed of 30 km / h. Since the KVA value is finally rounded off to the second decimal place, assuming that the inspection target can move beyond the 3m point, the C point (from the 3m point arrival time at the set speed of 30km / h). The KVA value is 0.1 from the point 0.18 seconds later to the point D (the point 0.18 seconds before the 3m point arrival time).
[0038]
Therefore, considering the reaction operation loss time, the KVA value of 0.1 is set to 0.33 seconds obtained by adding the reaction operation loss time 0.15 seconds to the 0.18 second from the 3 m point arrival time. In other words, the KVA value is 0.1 if a response signal is input within 0.33 seconds after the inspection target stops at the 3 m point. The time from the arrival at the 3m point may be measured by the control unit 20 from the start of moving object visual acuity measurement, or may be started after the inspection target arrives at the 3m point. If no response signal is input within 0.33 seconds, the KVA value is less than 0.1.
[0039]
The operation of moving object visual acuity measurement in the apparatus having the above configuration will be described (the inspection mode is the manual inspection mode).
[0040]
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 the visual target toward the eye to be examined at an apparent speed of 30 km / h. The movement of the prism 12 is controlled so as to approach. The target type is randomly determined by the control unit 20, and the type can be confirmed by turning on the lamp 35a.
[0041]
The subject presses the response button 4 when the target is discriminated while observing the target that is facing. When the response button 4 is pressed, the control unit 20 immediately stops the movement of the prism 12 and turns off the illumination light source 10 to make the visual 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 visual target is stopped and the KVA value correction data described above. Since the KVA value is a value that takes into account the reaction operation loss time, the reliability is higher than the conventional KVA value.
[0042]
After the subject presses the response button 4, the subject is asked to answer verbally the direction of the Landolt visual indicator. If the target direction answered by the subject matches the target direction in which the selection lamp 35a is lit, the moving visual acuity switch 34 is pressed to perform the second inspection. If the target direction answered by the subject is different from the target direction in which the selection lamp 35a is lit, it is an incorrect answer, so the incorrect answer input switch 36 is pressed to check the incorrect answer. When the incorrect 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 collected, and when a total of five examinations are completed, the average KVA value is displayed on the display unit 37, and the dynamic visual acuity examination is terminated. The inspection result is printed out from the printer 8 by pressing the print switch 38.
[0043]
In the above KVA value correction method, the reaction operation loss time is uniformly set to a predetermined time (0.15 seconds) regardless of age and gender. By changing the setting according to the age of the subject, the KVA value can be measured with higher accuracy. In this case, data for each age and gender is stored in advance in the memory 24, and a switch 40 for inputting age and gender on the operation panel 3 is provided as shown in FIG.
[0044]
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. When the button is pressed again, the gender input mode is set by the visual acuity value switch 33 in the same manner. With this setting, the corresponding reaction motion loss time correction data is called from the memory 24 and the moving object visual acuity value is corrected.
[0045]
<Embodiment 2>
In the previous embodiment, the response motion loss time obtained statistically was used as the basis of the correction data. However, in the second embodiment, the response motion loss time is measured for each subject before the dynamic visual acuity test is performed. By using the correction data, the measurement result can be selected with higher accuracy. Although the reaction operation loss time may be input to the apparatus of the first embodiment as measured by another measurement device, this is troublesome, and therefore a mechanism for measuring the reaction operation loss time is incorporated in the second embodiment. It is an example of the device.
[0046]
FIG. 7 is a diagram showing an operation panel of the apparatus of the second embodiment, and 50 is a switch for measuring reaction time. Since the other configuration is basically the same as that of the first embodiment (a neglected mark chart is added to the target plate 11), the description thereof is omitted.
[0047]
Hereinafter, the operation of the apparatus according to the second embodiment will be described with a focus on differences from the first embodiment (see the flowchart of FIG. 8). In addition, about each component, it demonstrates using the code | symbol same as Embodiment 1. FIG. The inspection mode is the manual inspection mode as in the first embodiment.
[0048]
First, the static visual acuity of the subject is first measured. The subject is instructed to look inside the apparatus from the measurement window 2 and the 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 target plate 11 to place the selected target on the optical path, and the prism 12 so that the optical distance of the target illuminated by the illumination light source 10 corresponds to the instructed visual acuity value. Move.
[0049]
In this state, the examiner proceeds with the examination while asking the subject whether or not the cut direction of the target can be determined. Examination is performed while changing the visual acuity value and the type of visual target, and if two or more correct answers out of three are obtained with the same visual acuity value visual target, it is assumed that there is visual acuity.
[0050]
Next, the reaction time measurement switch 50 is pressed to measure the reaction time of the subject. When the switch 50 is pressed, the control unit 20 presents an ignorance mark chart (the Landolt ring is not drawn) having the same brightness as when the target is presented. This is to reduce the difficulty in seeing the visual target due to the change in brightness and to prevent the detection of the reaction operation loss time.
[0051]
In presenting the inspection target, the examiner instructs the subject to press the response button 4 as soon as the direction of the cut of the target is known, and then measures the reaction operation loss time. The target switch unit 35 is used to select the target direction and present the target to the subject. A selection lamp 35a lights up for the selected target. Further, the visual acuity value of the presented visual target is controlled by the control unit 20 so that the visual acuity value that is two steps lower than the static visual acuity value obtained previously is presented. In this case, an inspection target having a visual acuity value that makes it easy for the subject to be viewed is acceptable. Therefore, the visual acuity value is not limited to two lower levels, but may be set to a lower visual acuity value by setting or a fixed test visual acuity value of 0.1 It may be a mark.
[0052]
The subject discriminates the direction at the moment when the examination target is presented, and inputs a response indicating that the discriminating can be made with the response button 4. When the response button 4 is pressed, the control unit 20 turns off the test target and measures and stores the reaction time from when the test target is presented until the response button is pressed (until a response signal is input).
[0053]
After the subject presses the response button 4, the subject is asked to answer verbally the direction of the Landolt visual indicator. If the test subject's answer is correct, the switch 50 is pressed to perform the second test. When the subject's answer is an incorrect answer, the wrong answer input switch 36 is pressed. When the incorrect answer input switch 36 is pressed, the measurement result at that time is not recorded and the same measurement is performed again. In this way, only the 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, but an intermediate value may be selected or three averages excluding the upper and lower limit values of the inspection value may be used. It is also possible to change the total number based on the judgment of the examiner.
[0054]
When the reaction time can be measured, the switch 34 is pressed to measure the above-described moving object visual acuity. When correcting the KVA value in the dynamic visual acuity measurement, the average reaction action loss time obtained previously as correction data is used. The measurement results of the static visual acuity value and the dynamic visual acuity value are printed out together with the measurement result of the reaction time from the printer 8 by pressing the print switch 38.
[0055]
As described above, since the reaction time for each subject can be obtained in advance, a more accurate KVA value can be obtained. Further, since the result of the reaction time is printed together with the KVA value, advice can be given in more detail individually by using both.
[0056]
For example, in the A subject and the B subject, both the static visual acuity value = 0.8, and it is assumed that the measurement result of both reaction times and the result of the KVA value considering the reaction time have the following relationship ( In the conventional measurement method that does not consider the reaction time, both KVA values = 0.4).
A Subject: Reaction time = 0.05 seconds, KVA value considering reaction time = 0.4
B subject: reaction time = 1.50 seconds, KVA value considering reaction time = 0.8
[0057]
Compared with static vision, the A subject has a large decrease in the KVA value, and the B subject has few. Therefore, it can be seen that the B subject is better from the viewpoint of visual function. The reaction time is better for the A subject and slower for the B subject. In driving a car, it takes a series of time to judge the information entered from the eyes and operate the limbs, and it cannot be said that the conventional measurement method includes this reaction time. , It was linked to the erroneous result of “decreased visual acuity”.
[0058]
In the case of the above example, it can be understood from the results of the KVA value and the reaction time that the A subject needs to increase the KVA value, and advice such as “I recommend to increase both static vision with appropriate glasses” is provided. it can. On the other hand, although the subject B is not bad in visual function itself, the reaction time is not good, so advice can be given, such as “Be prepared to deal with it on a daily basis”. Regarding the quality of the reaction time, a statistically obtained time may be used as a reference. It is also effective to obtain a KVA value by a conventional measurement method and print it out in the sense of comprehensive evaluation, or simply to obtain a KVA value obtained by a conventional measurement method and a reaction time measurement result. Effective advice can be given to each subject simply by displaying the information on the display or printing it out. It is also possible to display and print out a message based not only on the measured value but also on the reaction time and KVA value.
[0059]
In the first and second embodiments described above, the response button 4 is used and the target is discriminated by hand operation (although it can be a switch operation by foot), it is not good at fine finger operation. In the case of a non-examined subject, in the case of a subject who is incapable of limbs themselves, it is convenient to adopt a configuration in which the target is identified by voice. For example, as shown in FIG. 9, a microphone 60 for responding to the subject and a voice recognition unit 61 for recognizing voice are provided, and a response signal is input by the response button 4 (or joystick 5) by selecting the selection switch 62. Instead of, it is possible to respond by voice. In this case, it is sufficient to be able to recognize words such as “HIGH, NOI, WE, SHITA, MIGI, HIDARI”, and it is not necessary to provide complicated and expensive processing means such as voice recognition software. On the side of the apparatus, the same processing as when the signal of the response button 4 (or joystick 5) is input is performed by inputting the response signal by voice, and the dynamic visual acuity measurement and the reaction time measurement are performed.
[0060]
【The invention's effect】
As described above, according to the present invention, it is possible to improve the value including the reaction time from when the subject discriminates the target to when he / she responds, and to obtain a more accurate measurement result.
Moreover, by measuring the reaction time for each subject, this can be reflected in the measurement result, or appropriate advice can be given to the subject from the result of the reaction time.
[Brief description of the drawings]
FIG. 1 is a diagram showing an external appearance of an apparatus.
FIG. 2 is a diagram showing details of an operation panel.
FIG. 3 is a diagram illustrating an optical system and a control system.
FIG. 4 is a diagram illustrating an apparent distance of a visual target and a moving object visual acuity value corresponding to each distance.
FIG. 5 is a diagram showing a method of correcting a moving object visual acuity value after an inspection target arrives at a 3 m point.
FIG. 6 is a diagram showing details of the operation panel when the correction data includes age sex.
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 using voice is provided.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Apparatus main body 3 Operation panel 4 Response button 5 Joystick 8 Printer 20 Control part 22 Movement apparatus 40 Switch 50 Reaction time measurement switch 60 Microphone 61 Voice recognition part 62 Selection switch

Claims (2)

A moving visual acuity inspection apparatus that has a moving means for optically moving an examination target to be presented to the subject's eye toward the subject's eye and that measures the visual acuity of the subject's eye based on the target position when the subject responds Necessary to read the test target and to respond with response means after reading the test target after reading the test target. Storage means for storing a response time, and a calculation means for correcting the target position at the time of response based on the reaction time and a moving speed for moving the examination target toward the eye to be examined to obtain a moving body visual acuity. A moving visual acuity test apparatus characterized by the above. A moving visual acuity inspection apparatus that has a moving means for optically moving an examination target to be presented to the subject's eye toward the subject's eye and that measures the visual acuity of the subject's eye based on the target position when the subject responds The target position measuring means for obtaining the response target position when the subject reads the test target and responds by the response means, and the subject has the brightness of the target background but the target Reaction time to measure the reaction time of the subject from the presentation of the target to the response by the response means A moving body comprising: a measuring unit; and a calculation unit that corrects the target position at the time of response based on a moving speed of moving the reaction time and the test target toward the eye to be examined to obtain a moving object visual acuity. Vision test device.

Images