JP3490512B2 - Eye test - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a visual acuity test apparatus, and more particularly to an automatic visual acuity test apparatus suitable for a screening test such as a mass screening. 2. Description of the Related Art A plurality of targets having different visual acuity values are presented to a subject, and the subject's visual acuity is automatically determined by obtaining a response of the subject to the presented target. Automatic visual acuity testing devices are known. Conventionally, in this type of automatic visual acuity testing apparatus, a predetermined visual acuity value (for example, an average visual acuity value of 0.
From 7), the test was performed by changing the visual acuity value one step at a time in accordance with the response of the subject, starting with the presentation of the target. Also,
As an optotype used in the automatic visual acuity test apparatus, a Landolt ring optotype which responds to a break direction is generally used. [0003] However, in the automatic visual acuity test, irrespective of the visual acuity state of the subject, the test is always performed from a predetermined visual acuity value. For example, when the visual acuity value is larger than the visual acuity value presented in the above, there is a problem that the number of replies increases and the examination time becomes longer. Also, performing visual target presentation by sequentially changing visual acuity values one step at a time from the visual acuity value initially presented increases the useless visual target presentation depending on the subject's visual acuity state. was there. In addition, Landolt ring targets used in group examinations and the like are used in four directions of up, down, left, and right in order to perform quick measurement, but in order to perform accurate measurement, eight directions including four oblique directions are preferable. Have been. An object of the present invention is to provide a visual acuity test apparatus capable of performing an automatic visual acuity test in a short time with an efficient test procedure in view of the above-mentioned drawbacks of the conventional apparatus. [0005] The present invention is characterized by having the following configuration in order to solve the above-mentioned problems. (1) Optotype presenting means for selectively presenting a plurality of optotypes having different visual acuity values to a subject, input means for inputting a response of the subject, and correctness of the response input by the input means. In a visual acuity testing apparatus having a judgment
The initial value at the start of the program is a predetermined visual acuity value.
The first method, or the second method using an arbitrarily designated visual acuity value
The initial value determining means for determining whether
If the second method is selected, the
When switching the eyesight value, raise or lower the eyesight value one step at a time,
If one method is selected, the eyesight will be
Step of changing visual acuity value in multiple steps when switching values
And a program executing means for executing the inspection program based on the judgment result of the right / wrong judgment means . An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of the eyesight test apparatus main body 1. 2
Is a liquid crystal display panel, and an illuminating device such as a fluorescent lamp (not shown) is arranged on the back of the liquid crystal display panel 2 to illuminate the liquid crystal panel from behind. A Landolt ring visual target 3 for an inspection distance of 5 m is formed on the liquid crystal display panel 2. The Landolt ring target 3 has 14 visual acuity values of 0.1 to 2.0 (visual acuity values of 0.1 and 0.1).
5, 0.2, 0.3, 0.4, 0.5, 0.6, 0.
7, 0.8, 0.9, 1.0, 1.2, 1.5, 2.
0) is prepared. The Landolt ring of each visual acuity value has liquid crystal elements in a total of eight directions of four directions (up, down, left and right, and four diagonal directions) and eight fan-shaped liquid crystal elements between each of the cuts. By applying a voltage to other elements except for the above, eight types of optotypes having different cut directions can be presented. Thereby, the visual acuity value of 0.1 to 2.
In the case of the optotype presentation of 0, a total of 112 presentations can be performed. Reference numeral 4 denotes a light receiving unit for receiving a signal from a remote controller, which will be described later. Reference numeral 5 denotes a signal of the display content of the Landolt ring target 3 presented on the liquid crystal display panel 2 to the remote controller. This is a light emitting unit. Reference numeral 7 denotes a tripod seat corresponding to a camera tripod for fixing the visual acuity inspection apparatus main body 1 to the eye level of the subject. Reference numeral 8 denotes a hanging bracket for hanging the main body from a ceiling or the like by a chain or the like. At schools and the like, it may be difficult to attach a hook or the like to a wall surface, so that the main body can be installed by appropriately using these devices. As described above, the visual acuity inspection apparatus main body 1 has a simple structure with no moving parts, so that no special maintenance is required, and a general home power supply or a battery can be used as a drive power supply. . FIG. 2 is an external view of the remote controller 10. Reference numeral 11 denotes a window for transmitting and receiving data to and from the visual acuity inspection apparatus main body 1, and a light emitting unit having an LED for transmitting an optical signal and a light receiving unit for receiving an optical signal from the main body are provided inside. 12 is the visual acuity value of the presented target 0.1 to 2.0.
Is a group of eyesight value switches for arbitrarily selecting and setting. Reference numeral 13 denotes a start switch for auto measurement. Reference numeral 14 denotes a group of direction input switches for inputting the direction of the break of the Landolt ring, and has eight switches in four directions, that is, left, right, up, down, and oblique directions. The direction input switch group 14 serves as response input means for inputting the direction of the Landolt ring answered by the subject during auto measurement, and as direction specifying means for specifying the direction of the Landolt ring during manual measurement. . 15 is when the subject cannot answer at the time of auto measurement.
This is a switch for proceeding with the inspection program. Reference numeral 16 denotes a power switch for the main body and the remote controller. Reference numeral 18 denotes a mode switch for switching between measurement in four directions (up, down, left, and right) in the direction of the cut of the Landolt ring, and measurement in eight directions with a diagonal direction added. Reference numeral 20 denotes a liquid crystal display panel. 21 is a direction confirmation mark indicating the direction of the presented Landolt ring;
Is a display unit for displaying the visual acuity value of the presented target or an error message, 23 is a mark indicating whether or not auto measurement is performed, and 24 is a mode.
Designation by the mode switch 18 is four-way mode or eight-way mode
This is a mark that indicates whether the password is valid. FIG. 3 is a block diagram of the electric system of the apparatus. The signal input by each switch of the remote controller 10 is converted into an optical signal by the light emitting unit 31 via the control circuit 30 and sent to the light receiving unit 4 of the main body 1 of the visual acuity inspection apparatus. The signal received by the light receiving unit 4 is input to the main body control circuit 40 after being subjected to predetermined processing. Main unit control circuit 4
0 is the liquid crystal drive circuit 41 according to the input switch signal.
The optotype is displayed on the liquid crystal display panel 2 via. The main body control circuit 40 sends the signal of the target displayed on the liquid crystal display panel 2 back to the remote controller 10 via the main body light emitting section 5. The signal received by the light receiving unit 32 is converted into a predetermined electric signal and input to the control circuit 30. The control circuit 30 compares the transmitted optotype with the received optotype. If there is no discrepancy in the contents, the optotype is displayed on the direction confirmation mark 21 and the display section 22 on the liquid crystal display panel 2 via the display circuit 33. Display the direction and visual acuity value. Remote
If the transmission signal of the controller 10 is interrupted and does not reach the main unit, the signal of the main body light emitting unit 5 is not transmitted within a predetermined time, so that the control circuit 30 displays an error message on the display unit 22. Page. In this manner, the apparatus has a check function for preventing the presented optotype on the main body side from being inconsistent with the displayed optotype on the remote controller 10 side. The control circuit 3 on the remote controller 10 side
Numeral 0 has an inspection program for automatic measurement described below. When the control circuit 30 receives the signal of the start switch 13 for auto measurement, the control circuit 30 starts the inspection program, and determines whether the response of the subject input by the direction input switch group 14 or the switch 15 is correct or incorrect. The target to be determined and presented is sequentially switched (this procedure will be described later).
As a result of the determination of each response, if the number of correct answers equal to or more than a reference is obtained for a certain visual acuity value, it is determined that the visual acuity value is possessed. Reference numeral 42 denotes a buzzer, and reference numeral 43 denotes a drive circuit. When the control circuit 30 determines the eyesight of the subject and ends the auto-measurement test, the control circuit 30 transmits a test end signal to the main body through the light emitting unit 31 and a display unit displayed on the liquid crystal display panel 20. The visual acuity value number 22 is blinked. When receiving the inspection end signal, the main body control circuit 40 operates the buzzer 42 via the drive circuit 43. Thus, the examiner can know the end of the examination and the determined visual acuity of the subject. The operation of the apparatus having the above configuration will be described separately for manual measurement and automatic measurement. (Manual measurement) The subject is measured from the eye test device main body 1 to 5
After being positioned m meters away, a visual acuity test begins. In order to perform an accurate visual acuity test, the mode switch 18 is used to set the direction of the discontinuity of the Landolt ring of the presented target in eight directions. The examiner presses a switch of a desired visual acuity value in the visual acuity value switch group 12. When the visual acuity value switch is pressed, the control circuit 30 sets the direction of the discontinuity of the Landolt ring of the visual acuity value. The direction of the discontinuity of the Landolt's ring is programmed to change randomly each time the visual acuity value switch is pressed. The signal of the target content determined by the control circuit 30 is input to the main body control circuit 40 via the light emitting section 31 and the main body light receiving section 4, and passes through the liquid crystal drive circuit 41 to the visual acuity value input to the liquid crystal display panel 2. A sign is presented. Also,
On the liquid crystal display panel 20 of the remote controller 10, a Landolt ring in the same direction of the cut line and the number of the input visual acuity value are displayed, so that the examiner can see the optotype presented on the main body 1 of the visual acuity test apparatus. Without this, it is possible to judge whether the response of the subject is correct or not. When it is desired to change the direction of the discontinuity of the Landolt's ring with the same visual acuity value, a desired switch of the direction input switch group 14 is inputted to change the direction, and the inspection is performed. By repeating these operations, an accurate eyesight test of the subject can be performed. (Automatic Measurement) The automatic measurement is started when the visual acuity value of the target presented at the first time (at the start of the test) is selected and designated arbitrarily. -There are two ways to set up. First, the auto-measurement operation when the visual acuity value of the target presented at the first time is arbitrarily specified and started will be described with reference to the flowcharts of FIGS. The automatic measurement for designating the visual acuity value is used when the visual acuity of each subject is known to some extent.
In a visual acuity test conducted at a school or a company, there are many cases where the results of the previous test remain on a medical checkup card, etc.
There are few cases in which the eyesight fluctuates greatly in 2 years. Therefore, as the visual acuity value of the optotype presented for the first time, for example, the visual acuity of the previous result can be used. The selection and input of the visual acuity value is performed by pressing the switch of the visual acuity value to be presented in the visual acuity value switch group 12, as in the manual measurement described above. Liquid crystal plate 2 on the side of the eyesight inspection device main body 1
Displays an optotype having a specified visual acuity value. Subsequently, the examiner inputs the auto measurement start switch 13. Remote
In response to this signal, the control circuit 30 of the remote controller 10 stores the direction of the break presenting the Landolt's ring and the visual acuity value (step 1-1), and the liquid crystal display panel 20 of the remote controller 10. The upper mark 23 is displayed and the inspection program for auto measurement is executed. When the examiner confirms the execution of the auto measurement on the display of the mark 23, the examiner asks the examinee for the direction of the break of the Landolt ring currently presented, and changes the direction in which the examinee responds to the direction input switch. An input is made by a switch of the group 14 (when there is no answer or when the answer is invisible, the switch 15 is pressed). The control circuit 30 determines whether the input direction and the direction of the cut of the Landolt ring of the presented target are correct (step 1).
-2). In the auto-measurement of this embodiment, when three correct answers are obtained during the presentation of the optotype having the same visual acuity value four times, the subject is determined to have the visual acuity value. A case where it is determined that an error (not visible) in the first optotype presentation will be described. If the presented target is not the lowest visual acuity value of 0.1 (step 2-1), the control circuit 30 sets the target to be one greater (the visual acuity value is reduced by one) (step 2-2). The direction of the break in the Landolt ring is
It is programmed so that it changes randomly each time the target changes. If the lowest visual acuity value is 0.1 in step 2-1, the process proceeds to step 2-10. Step 2
The examiner asks the examinee about the direction of the cut of the Landolt's ring, and presses the direction input switch group 14 in the answered direction. The control circuit 30 determines the correctness (step 2-3), and if an error is detected, returns to the previous step 2-1 and repeats this routine until a correct answer is obtained in the step 2-3. If a correct answer is obtained in step 2-3, measurement is performed up to three times with the same visual acuity value (step 2-4). Two incorrect answers during this measurement (step 2
If -5), the process returns to step 2-1 again, and if it is correct twice (step 2-6), the visual acuity value is increased by one (step 2-7). If the correct answer is twice in the routines in steps 2-4 to 6, the total of three correct answers including the correct answer in step 2-3 has been obtained, so the final visual acuity presented in step 2-3 is obtained. Although it is determined that the visual acuity value has the minimum value, there is a possibility that the visual acuity value may be higher by one. Therefore, the visual acuity value is increased by one in step 2-7. When the visual acuity value is increased by one in step 2-7,
It is determined whether the visual acuity value has already been measured four times and the wrong answer has been made twice (step 2-8). The eyesight of the examiner is determined. If the wrong answer has not been reached twice, it is determined whether the eyesight value has not been measured once (step 2-9). If the target is present at a visual acuity value one step higher than the presentation, the process proceeds to step 3-1 to be described later, otherwise, the measurement is performed using the same visual acuity value (step 2-10). If the answer is incorrect in the determination of correctness of the measurement in step 2-10 (step 2-11), it is determined whether the visual acuity value has reached the lowest visual acuity value of 0.1 (step 2-12). ), When the visual acuity value reaches 0.1, it is determined that the visual acuity value is 0.1 or less, and when the visual acuity value does not reach 0.1, the visual acuity value of the preceding presented target is determined to be the visual acuity of the subject. You. If the answer is correct in the judgment of correctness in step 2-11, if the visual acuity value has reached the highest visual acuity value of 2.0 (step 2-13), if the visual acuity value has reached 2.0, the visual acuity value The value 2.0 is determined to be the eyesight of the subject, and when the eyesight value has not reached 2.0, the process returns to the previous step 2-7, and the measurement and the determination are repeated in the same manner. A case will be described in which the subject's response is determined to be correct in the first optotype presentation. In this case, the visual acuity determination program is a program in which steps 2-1 to 13 are substantially reversed in pattern. In Step 3-1, if the presenting visual target has the highest visual acuity value of 2.0, the visual target that is one size smaller (up one stage) is presented if the visual acuity value is not 2.0 (Step 3-). 2). If the response is correct in the right / wrong judgment (step 3-3) in presenting the optotype, the process returns to step 3-1. If the response is incorrect in the determination in step 3-3, measurement is performed up to three times with the same visual acuity value until there is a wrong answer during the measurement (step 3-4). If there is no wrong answer during the measurement, the process returns to step 3-1. If there is a wrong answer, the visual acuity value is increased by one (step 3-6). In step 3-6, it is determined whether or not four measurements have already been made and three correct answers have been obtained (step 3).
According to -7), if three correct answers have been obtained, the visual acuity value is determined to be the visual acuity of the subject, otherwise, it is determined whether or not the visual acuity value has not been measured once. It is determined (step 3-8). If the visual acuity value in step 3-6 has not been measured at all, the process proceeds to step 2-1. If the visual acuity value has been measured even once, the measurement is performed using the visual acuity value (step 3-9). If the correctness of the measurement in step 3-9 (step 3-10) gives three correct answers together with the previous determination, the visual acuity value is determined to be the visual acuity of the subject. You. If two correct answers have not been obtained, then it is determined whether or not two incorrect answers have been reached (step 3-11).
Therefore, if two incorrect answers have not been reached yet, the process returns to the previous step 3-9 and the measurement is repeated. If two wrong answers have been reached as a result of the determination in step 3-11, it is determined whether the visual acuity value is the lowest visual acuity value of 0.1 (step 3-12).
At 1, the eyesight of the subject is determined to be 0.1 or less. If the lowest visual acuity value has not reached 0.1, the process returns to the previous step 3-6, and the measurement and the determination are repeated. When the eyesight of the subject is determined by the auto measurement in this way and the examination is completed, the control circuit 30 activates the buzzer 42 via the drive circuit 43 to notify the examiner of the fact, and Then, the visual acuity value number of the display unit 22 displayed on the liquid crystal display panel 20 is flickered, thereby informing the examiner of the determined visual acuity. As described above, the visual acuity value is first specified and the
By starting the measurement, for example, eyesight 2.
When examining a subject having an average visual acuity value of 0.
Starting from the presentation of the optotype 7, seven steps of measurement from 0.7 to 2.0 are required, but starting from the presentation of the optotype with the visual acuity 1.5 from the prior information (the previous test result etc.) The inspection can be completed by two-stage measurement of 5 and 2.0. Next, the operation of auto measurement when starting from a certain visual acuity value stage will be described. FIG. 6 is a flowchart for explaining this auto measurement operation. Remote
If the auto-measurement start switch 13 is input without depressing the switch of the visual acuity value switch group 12 of the controller 10, the apparatus first presents a target having a predetermined visual acuity value. As the visual acuity value of the initially presented visual target, for example, starting from the presentation of the visual acuity value visual target with an average visual acuity of 0.7 (step 4-1). As described above, the examiner presses the switches of the direction input switch group 14 in response to the subject. The apparatus determines whether the response input is correct or not (step 4-2), and presents a target having a visual acuity value of 1.0 three levels higher if correct (step 4-3). If the response is incorrect, an optotype having a visual acuity value of 0.3, which is four steps lower, is presented (step 4-4). Thereafter, the process proceeds to step 1-2 of the above-described auto measurement program.
A visual acuity determination is made based on a visual acuity value change step by step. For example, when examining a subject having the visual acuity of 2.0 as described above, the visual acuity values of 0.7, 1.0,
It is possible in five stages of 1.2, 1.5 and 2.0. In this way, for subjects who do not have prior information, starting from a certain visual acuity value, the second optotype presentation is not a one-step visual acuity value change, but skips to a certain stage to reduce the total number of measurements. Can be done. The visual acuity values 0.7 and 1.0 shown in FIG.
And 0.3 are merely an example of numbers, and may be changed according to the subject to be examined. In addition, before moving to the automatic measurement program for the visual acuity value change by one step, the visual acuity value may be further increased to another certain level. As described above, the present invention can be variously modified, and these are included in the present invention as long as the technical ideas are the same. As described above, according to the present invention, a visual acuity test can be performed in a short time with an efficient test procedure in an automatic visual acuity test.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing a front view of a main body of an eyesight inspection apparatus. FIG. 2 is a view showing an external view of a remote controller. FIG. 3 is a configuration diagram of an electric system of the apparatus. FIG. 4 is a flowchart for explaining an auto-measurement operation in a case where a visual acuity value of an optotype presented for the first time is specified and started. FIG. 5 is a flowchart for explaining an auto measurement operation when the visual acuity value of the target presented at the first time is arbitrarily specified and the start is performed. FIG. 6 is a flowchart for explaining the operation of auto measurement when starting from a certain visual acuity value stage. DESCRIPTION OF SYMBOLS 1 Main body of visual acuity test apparatus 2 Liquid crystal display panel 3 Landolt ring target 10 Remote controller 12 Visual acuity value switch group 13 Start switch 14 Direction input switch group 30 Control circuit 40 Main body control circuit

Claims (1)

(57) [Claims] 1. An optotype presenting means for selectively presenting a plurality of optotypes having different visual acuity values to a subject, and input means for inputting a response of the subject; A visual acuity test apparatus having a right / wrong judgment means for judging whether a response inputted by the input means is right or wrong.
The initial value at the start of the program
The first method is a value, or the second method is an arbitrarily specified visual acuity value.
An initial value determining means for determining between two methods;
If the second method is selected by the step, the response of the subject
When changing the eyesight value accordingly, increase or decrease the eyesight value one step at a time.
If the first method is selected, respond to the subject's response.
When changing the visual acuity value by pressing
A program storage means for storing a test program including steps, the test based on the determination result of said correctness determination means
And a program executing means for executing an inspection program.