JPS6227918A - Automatic sight examination method and automatic optometer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Industrial application The present invention selectively presents a specific visual target from among a plurality of visual targets to a subject, and shows the visual recognition state of the visual target to the subject. The present invention relates to an automatic visual acuity measuring method for measuring the visual acuity of a subject by having the examinee answer the questions and automatically executing the test according to a predetermined test routine depending on whether the answers are correct or incorrect, and an automatic visual acuity meter therefor.

A predetermined optotype is selected from among multiple optotypes, presented to the test subject, and the testee is asked to answer the state of visual recognition in response to this, and the test is automatically performed based on the answer. Automatic visual acuity meters that determine visual acuity have been in practical use for some time. This automatic visual acuity meter is configured such that the optotype presentation routine starts from an optotype with a visual acuity value of 0.1 and sequentially presents optotypes with one visual acuity value in steps of 0.1. During the optotype presentation routine, for example, if an incorrect answer is given to the presentation of an optotype with a visual acuity value of O19, the visual acuity of the subject is determined using the visual acuity value one step below that, 0.8.

By the way, automatic vision meters are generally used for group medical examinations and driver's license vision tests.

In this case, if the visual acuity target is always presented step by step with a visual acuity value difference of a certain step from the visual acuity target of a specific visual acuity value as described in -, it is difficult to The test subject has to respond to the presentation of the target, which not only makes the test subject unnecessarily fatigued, but also makes it impossible to perform the visual acuity test efficiently.

Spring 8! i...! In view of the drawbacks of the conventional automatic visual acuity side, the present invention eliminates as much as possible the display of optotypes that are not directly related to visual acuity determination, efficiently and without causing undue fatigue to the subject. An object of the present invention is to provide an automatic visual acuity test method that can measure visual acuity with high accuracy, and an automatic visual acuity meter for the same.

The automatic visual acuity testing method according to the present invention selectively presents a plurality of optotypes with different visual acuity values to the test subject, and automatically performs a visual acuity test based on whether the visual recognition of the optotypes is correct or incorrect. In method C□2, the first step is to present an optotype with a predetermined visual acuity value N; If the answer is r + 'F-l, then the visual acuity (l!'IN
Yo! /) High visual acuity (+l￥ (N +-0, 1) is presented next, and if the above answer is [wrong], a predetermined visual acuity value M (however, M<N) is presented next. 4M; after that, the visual acuity value (N − t n ,
n-(], 2, 0.3.

...or M(n, m=0.], 0.2. ・
・+.

N O,1) is presented, and the answer that is inclined to the presented visual target of a certain visual acuity value (N+n or M+-m) is 1 wrong -.
j, the visual acuity value of the visual target one step before the presented visual target is determined as the visual acuity of the subject.

Also, does the automatic vision system 1 according to the present invention have different visual acuity values? M
an optotype presenting means for selectively presenting a number of optotypes to a subject; an answering means operated by the subject to answer an answer corresponding to the presented optotype; and the answer.・In an automatic visual acuity meter having a determination means for determining whether the answer from the stage is correct or not, and a control means for controlling the optotype presenting means to present the next necessary optotype based on the determination result of the determination means , the control means first presents an optotype with a predetermined visual acuity N to the optotype presenting means, and when the determining means determines that the answer from the answering means is "correct", the optotype presentation means Once an optotype with a visual acuity value (N + O, I) higher than N is presented to the means, and when the judgment means determines that the visual acuity value (N + O, I ) is 1-false, the optotype presenting means is given a predetermined value of M (M< If the answer from the answering means is determined to be [correct] after 1 meter, the visual acuity value of QJ- (N → n, n = 0) is presented. .2゜0.3...or M''-
m, m-0,1, (], 2, ..., N
-0, 1 are presented to the optotype presenting means, and the answer from the answering means is the same visual acuity value (N+n or M+m
) is judged as "wrong" multiple times iJ visual acuity value of the optotype presented immediately before that optotype N -L rl
o, 1 or M + rn-0, 1 is controlled to determine the subject's visual acuity.

One Effect of the Invention The present invention has an improved optotype presentation routine, which eliminates as much as possible the presentation of optotypes that are not directly related to visual acuity determination, and improves efficiency without causing undue fatigue to the subject. This method has the advantage that visual acuity can be measured accurately and with high precision.

Embodiment (1) External structure FIG. 1 is an external perspective view showing an embodiment of an automatic visual acuity testing device (hereinafter referred to as a visual acuity meter) according to the present invention. Pedestal 10
The operation panel 1) located in front of the subject on the subject's side includes a start switch 12 consisting of a push button switch for starting the measurement, and a start switch 12 for answering the cut direction of the Landolt optotype visually recognized by the subject. An answer switch 13 is provided. An apparatus housing 15 stands upright on the pedestal 10, and on the front side of the housing 15 facing the examinee, there are two windows 16a and +6b for allowing the examinee to look at the optotype with both eyes, and a forehead rest member 17. and are provided.

In addition, the housing 15 has a printer 1 that prints out the test results.
9 is installed. This printer has "
Calendar manual device f for inputting year, month, and day
] 9 has a.

As shown in FIGS. 2A and 2B, the answer switch 13 includes a pyramid-shaped central protrusion 20, push button switches 21 to 24 arranged on the front, back, left and right sides of the pyramid-shaped central protrusion 20, and each of these push button switches. It consists of Landolt marks 21a to 24a that are displayed close to each switch in order to show the subject which cut direction of the Landolt optotype corresponds to. Even if the subject is constantly looking into the windows 16a and 16b, this configuration allows the subject to select the answer switch 13 based on the tactile sensation of the central protrusion 20.
The entire arrangement of the buttons and the positions of the pushbutton switches 21 to 24 can be known.

An examiner operation panel 30 shown in FIG. 3 is disposed behind the top surface 18 of the housing 15. This operation panel 30 includes a power switch 301 consisting of a toggle switch with a built-in pilot lamp, a measurement sequence setting knob 302, a visual target presentation time setting knob 303, and examination menu setting switches 304 to 310 consisting of push button switches.
, an astigmatism chart light switch 31), an optical path selection switch 312 for selecting whether to put the astigmatism chart into the left eye optical path or the right eye optical path, and a push button provided to end the measurement. A button-type end switch 313 and each inspection menu setting switch ON - OFF F? Pilot lamps 304a to 3 for displaying status
10a, false pilot lamps 315a and 315b that indicate which eye is being measured, left eye or right eye, and visual acuity 0.
．． Judgment lamps 316a and 316b for indicating the judgment result of measurement using the optotype for 7 as "pass" or "fail", and a liquid crystal display panel for indicating the visual acuity value of the optotype presented to the subject during the measurement. 320 are arranged.

Here, each of the above-mentioned pilot lamps 304a to 316
b is composed of LED.

(2) Optical system FIG. 4 is an optical layout diagram of this visual acuity meter. The right eye optical path OR and the left IR optical path OL have the same configuration. The light emitted from the optotype illumination light source 40R1401 is transmitted through the concave mirror 41R14.
After being reflected by 1L, it illuminates the optotype plate 42R142I7. The optotype board 42R142■7 is the window 16a, 16b mentioned above.
It is arranged at the focal position of the distance lenses 43R, 431 arranged in the.

The light from the optotype plate 42R142L is a half mirror 44R1
After being reflected by 44I7, mirror 45R145I5.4
The light is reflected by 6R and 46L, is made into a parallel light beam by lens 43R143L, and enters eye E to be examined.

Normally, when testing one eye's visual acuity, a visual target is not presented to the credit sales person, but it is said that it is necessary to provide a bright field similar to that of the eye to be measured. Therefore, in this embodiment, the bright field light source 47R147■7 and the diffusion plates 48R, 48L
have. For example, when examining the right eye, light source 4
The optotype plate 42R is illuminated with 0R, and the optotype is presented to the subject's right eye ER.

At this time, the light source 47■ of the left eye optical path 0■ is also turned on, and the light diffused by the diffuser plate 481 passes through the half mirror 44L and is reflected by the mirrors 45L and 46L, and the light source 47■ of the left eye optical path 0■ is turned on.
gives a bright field.

The distance lens 43R143L includes an auxiliary lens group 49R1.
It has 49L. These auxiliary lens groups 49R and 149L are, for example, lenses 49 for farsightedness inspection having a refractive power of +0.5D.
1R, 491) 5, for example, a near vision inspection lens 492R, 1492L having a refractive power of +3.0D, and pinhole plates 493R, 493L having a large number of pinholes.

These auxiliary lens groups 49R149L are held by a turret plate 495R1495L, as shown in FIG. 5, and are selectively inserted into their respective optical paths. Turret plate 4
95R and 495L also have a clear aperture 494
R1494L is formed and placed in each optical path during distance inspection.

These turret plates 495R, 495L have gears 498R, 498 on their rotating shafts 497R, 497L, respectively.
It has L. A tension belt 499R1499L is attached to these gears 498R and 498L.
2 bells) 499R1499L is a pulse motor-4
The hook is passed to a gear 496a attached to one end of the rotating shaft of 96.

With this configuration, the turret plate 4 is rotated by the rotation of the motor 496.
95R1495L is rotated.

On the other hand, at the other end of the rotating shaft 496a of the motor 496, a slit plate 500 having a (J slit plate 500a) is attached (N
t 4J and C are here. This Surin L 500a corresponds to the aperture 494R14971,,, and when the Surin 71 and 500a move to the position of the photointerrupter 501 which is the detector, the aperture 494R1494L corresponds to the optical path O1 of each phase. ? ,OI,
It is configured to be located within.

The optotypes (J42R142I, as shown in FIG.
It consists of 23. The diffusion plate 421 functions to diffuse the light from the light source 40.

As shown in FIG. 6, various patterns 401 to 409 are formed on the liquid crystal plate 422, which turn black when energized. Patterns 401 to 4 corresponding to visual acuity of 0.1 to 0.5 among Landolt optotype patterns 4 old to 409
05, the circular arc portion 401a and each cut portion 401b are formed independently so that cuts in four directions can be selectively switched and displayed.

For example, except for the right side opening 416b,
A rightward Landolt optotype is obtained by ffi blackening. On the other hand, in patterns 406 to 409 corresponding to visual acuity of 0.6 to 0.9, the cut direction is, respectively.
” - consists of four Landolt optotypes located on the bottom left and right as a group.

Further, a sunburst type astigmatism table pattern 410 is formed on the liquid crystal panel 422, and a clock time display pattern 41) is formed on each meridian so that the direction thereof can be easily determined. Below the astigmatic table pattern 410, a single row shutter pattern 412 is formed by arranging 16 rectangular patterns 412a in a row. A group of shutters 413 for a stereoscopic chart that controls the presentation of stereoscopic charts 1 to 1 to be described later is formed further below the shutter row pattern 412.

As shown in FIG. 7, the mask plate 423 is placed at a position corresponding to the rectangular pattern 412a of the above-described one-row shutter pattern 412, and has four vertical and horizontal directions corresponding to visual acuities of 1.0.1.2.1.5 and 2.0. A total of 16 directional Landolt optotypes 415 are arranged in groups of four. In this embodiment, optotypes corresponding to visual acuities of 1.0, 1.2.1.5.2.0 are arranged from the right side in the figure.

Below the Landolt optotype row 416, there are five summer-type openings.
The first part 416a, 416b, 416c, 4]6d, and 416e are the stereoscopic chart shutter group 4 described in
A mask portion 417 formed corresponding to 13 is formed. Four small heat molds 418 are formed in each of the openings, one of which is shifted in position from the other small heat molds in the horizontal direction. For example, the small heat mold 419a in the opening 416a has a center-to-center distance of DI (D, >S) with respect to the reference center-to-center distance S of other small heat molds. One small heat mold 41 within the other openings 416b to 416e
9b to 419e also have center-to-center distances of D2 to D2, respectively. Here, >I”+2>D3 >D
4>s>Ds, and the deflection directions in this embodiment are all in the right horizontal direction.

In this embodiment, the stereoscopic chart 416a has a disparity of 4', the chart 416b has a disparity of 1', and the chart 416c has a disparity of 3'.
', chart 416d has a parallax of 30'', chart 4]
6e is configured to provide a parallax of 2', respectively.

The embodiment shown in FIG. 7 is a right eye mask plate, and the left eye mask plate is formed in mirror symmetry with the mask plate shown in FIG. Each of the patterns 415 and 417 described above is formed by chromium vapor deposition on a glass substrate.

(3) Electrical system FIG. 8 is a block diagram showing the electrical system of this visual acuity meter. The electrical system includes a ROM (read only memory) 606 that generates an inspection sequence program, which will be described later.
RAM (RAM) that stores inspection data temporarily or permanently
A CPU (Central Processing Unit) 607 for controlling the entire electrical system according to sequences stored in a random access memory) 608 and a ROM 606, and a drive system 600 for each of the aforementioned components.
and an interface 605 that communicates between the drive system 600 and the CPU 607.

A CTC (counter timer circuit) 609 is connected to the CPU 607 . The CTC 609 supplies the CPU 607 with pulses for controlling the rotation of the pulse motor 496 and pulses for selecting the cut direction of the Landolt optotype presented by the liquid crystal plate 422R1422i of the optotype board 42R142L. CT
For C609, the last four digits are shown as l 1 ]
It is configured as a Datsun counter that gradually decreases from IJ to ro 000J. This down counter starts at the same time as the power is turned on and is constantly executed.

Table 1 The CPU 607 reads the count of the CTC 609 immediately before the visual target presentation step, and the last two digits of the count value are 1) 1
'', the Landolt optotype break is on the ``top'', ``10'' is on the ``bottom'', ``Ol'' is on the ``right'', and ro 0J is on the ``right''. Select each Landolt optotype as shown on the left. With this configuration, the start switch 12 can be operated by the examinee from power-on.
Due to the randomness of both the time from turning on the power to the answer switch 13 and the time from when the power is turned on to the reply by the answer switch 13, the direction of the break in the Landolt optotype is presented at random.

The drive system 600 includes an operation panel 30 and a liquid crystal panel 320 thereof.
Driver circuit 601 for driving, light #40R14
01), a driver circuit 602 for lighting up 47L and 47R, and each liquid crystal board 42 of the optotype board 42R142L.
Driver circuit 603 for driving 2R1422L.
604, a speaker 610 and its driver circuit 61 for outputting sound when there is an answer by an answer switch
It is roughly composed of.

■1 constant M−v 辷BξL斐21) This is −0:)! 1 Year (1) Overall Measurement Flow FIG. 9 shows a flowchart showing the entire measurement procedure by this visual acuity meter, and will be explained in detail below.

"Step 1": Switch the power switch 301 of the operation panel 30 to "Person" and turn on the power.

Step l-2: CPU 607 uses interface 60
5, it is determined whether the photo ink clubter 501 detects the slit 500a, that is, whether the element 1f)lL7c++-494R1494L is located in the optical path. When the photointerrupter 501 does not detect the slit 500a, the pulse motor 496 is rotated by the pulse output from the CTC 609 to move the aperture 494R14941 into the optical path. Also, CP +J [107iJ: I
? The data stored in A M 608 is J″I+iii times.

Step 1-3: The examiner uses the operation panel 30 to select and set the measurement sequence, examination menu, and optotype presentation time. Of course, the measurement sequence is set by the setting knob 302, and when testing either the naked eye or the corrected eye, the knob 302 is set to the "naked" or "corrected" position.

Corrective examination after inspection with naked eye If you want it to run automatically, Knob 302 1 naked eye 10 correction 1 set in position.

Next, consider the age of the subject and the test. Taking into account experience, familiarity, etc. Adjust the optotype presentation time using the knob 303. Decide. In this example, When set to [1], 3 seconds, 5 seconds when you hit ``2'' seven times, 7 seconds when set to r3J The visual target presentation time is obtained. Correction The time is done by the CPU 607, When the desired time comes CI') LJ Driver circuit 603 by 607 Control to erase the optotype.

The inspection menu is a push button Press the switch 304 or 310. Set by Zuko.

“Binocular” menu (switch 310) is right lFI test, left eye test After that, it will automatically proceed to a binocular review of the matter. to move the target. This [both eyes] Left when not selecting menu Right [IN each eye examination and lf.

Step 1-4: The CPLJ 607 reads the measurement sequence, examination menu, and optotype presentation time set in the previous step, and then turns on the light source 40R in the right eye optical path and the light source 47b in the left eye optical path to complete measurement preparation.

Step 1-5: The CPU 607 determines whether or not the start switch 12 has been turned on by the subject. If it has been turned on, the process proceeds to the next step 1-6. If it remains OFF, the process returns to the previous step 1-3 so that it can respond to changes in the measurement sequence or inspection menu.

Step 1-6: Execute a measurement processing subroutine to be described later based on the setting measurement sequence, setting inspection menu, etc. read in step 1-4.

Step 1-7: Count the number of times the CPLJ 607 passes through the set inspection menu, that is, the number of times it is executed.

Step]-8: The CPU 607 determines whether or not it is necessary to proceed to step 1-9, which determines the number of times the previous step 1-7 has passed, according to the setting measurement sequence.

Measurement sequence is "naked eye + correction" If it was set to Proceed to step 1-9. "naked eye" or set to “Correction” If so, proceed to the next step 1-9. Step 1”0 Move to.

Step 1-9 = Check whether the number of passages counted in Step 1-7 is 2 or more, that is, two inspections: an inspection of the all-setting inspection menu with bare Off and an inspection of the all-setting inspection menu in the correction state. Determine whether or not the has been executed.

Two tests were conducted Go to next step 1”0 Transition. If it is less than 2 times, Step 1” Move to 1 and Glasses or contacts for the examiner In the corrected state by wearing lenses Prepare for the vision test. preparation After completion, the test subject presses the start switch. Turn on switch 12 again. Step 1”2), Step 1- Repeat steps 6 and below. and perform a correctional status efficacy test. do.

If it is determined in step 1-9 that the number of il passes N≧2, the measurement result, that is, the visual acuity of the subject is printed out by the printer 19. In addition to visual acuity values for each of the left and right eyes, the printout also includes binocular visual acuity, pass/fail determination results for the 0.7 precision test, results for stereoscopic vision ability, etc., depending on the setting test menu. Furthermore, the inspection date set by the calendar input device 19a is also printed.

After completing the printout The device is ready for the next patient. It returns to step 1-2 and returns to the initial state. Become.

(2) Measurement processing subroutine FIG. 10 is a subroutine flowchart showing steps 1-6 of the above-mentioned measurement processing in more detail. CPU
607 determines whether or not it is necessary to execute the measurement processing step (step 2'' to step 2-6) based on the inspection menu read in step 1-4, and the determination result is r
If YES, each test (step 2-7 to step 2''2) is executed. The subroutines of each test will be explained below. In addition, farsightedness check test (Step 2-
9) or pinhole check test (Step 2)0
) is selected, the CPU 607 is configured to first execute the distance visual acuity test (steps 2-7), then execute each test step, and compare the test results of the two. There is.

(3) Screening test 1) Figure shows a flowchart of the screening test. This screening test consists of the distance visual acuity test (step 2-7>,
Near vision test (Step 2-8), farsightedness check test (Step 2-9) and pinhole check test (
In step 2'0), the left eye, right eye, and both eyes are tested simultaneously. However, during the near visual acuity test, the lenses 492R and 492L are used, during the farsightedness check test, the lenses 491R and 491L are used, and during the pinhole check test, the pinhole plate 493R is used.

The difference is that 493L is inserted into each optical path.

When inserting these lenses, the CPU 607 calculates the number of pulses and CT pulses stored in advance in the ROM 606 corresponding to each lens.
This is executed by rotating the motor 496 by matching the number of pulses input from C609.

The operation of each step will be explained below using a distance visual acuity test as an example.

Step 3: The CPU 607 first turns on the pilot lamps 304a and 315b to indicate to the examiner that the distance visual acuity test will be performed from the right side of the subject. Next, the CPU 607 clears the previous data stored in the failure number storage area of the RAM 60B and resets it to zero.

Step 3-2: The CPU 601 uses the driver circuit 60
3, among the Landolt optotypes 407 with visual acuity of 0.7 on the liquid crystal panel 422R, the Landolt optotypes in either the left, right, top, or bottom cut direction are captured and displayed from the combination of the last two digits of the count value of the CTC 609 at that time. , waits for an answer from the subject using the answer switch 13. When you press the switch 13, the speaker 61) will emit a beep, confirming the switch response. At the same time, the presented visual acuity value of 0.7 is digitally displayed on the liquid crystal panel 320.

Here, each of the Landolt optotypes is blinked for a predetermined period of time, for example, 0.5 seconds at the initial stage of presentation, to make it easier for the subject to visually recognize the presentation position. In this embodiment, the counter from CTC609 is read by CP[J607, the count of CT C6(]9 is done every 0.1 m5ec, and when the last digit of the Callan I value is [IJ], the LCD screen Achieved by controlling the 1-rime circuit 603 with CP [, +6 07 to drive 422R to present the visual target, and stop driving when the last digit is [0]] - and not to present the visual target. be done.

CP LJ 607 is from the subject. Landolt with answers provided If it matches the cut direction of the visual target If so, move on to step 3-4. Ru. If the answers do not match, No response within visual target presentation time If so, move on to step 3-3. do. Spit when the answers do not match. 61) is pronounced as 1 B H] shout and warn the subject.

Step 3-3: CP (J607 is the CT at the time of executing this step and starting the step C609's call 1'1
The cutting direction of the Landolt optotype is determined based on the last two digits of the 1-value, and the driver circuit 603 is controlled to present the Landolt optotype 401 with visual acuity of 0.1. FIG. 12 shows an example of the presentation. At the same time, the display on the liquid crystal board 320 is changed to 0.1.

CP[J607 is from the subject. whether or not there is an answer within the given time and its Presentation of answers for Landolt optotypes Determine if it matches or does not match the cut direction. and in the case of rYEsJ, the step Go to step 3-4 and check if there is a discrepancy. or if no answer, step 3 ” 1, and the subject's visual acuity is less than 0.1 RAM608 1a, and then the next Stella. Move to step 3'2.

Step 3-4: Visual target that is one step smaller than the previously presented visual target (target with visual acuity of 0.7 if the previous step was Step 3-2, visual target with visual acuity of 0.1 if the previous step was Step 3-3) A target, that is, a visual target one step higher in visual acuity value (a visual target of 0.8 when the previous step is step 3-2, a visual target of 0.2 when the previous step is step 3-3) is presented. At this time as well, the cutting direction of the Landolt optotype to be presented is determined from the last two digits of the count value of the CTC 609 at that time. Figure 12B shows an example above the 0.6 Landolt optotype. The liquid crystal panel 320 displays 0.8 or 0.2.

Step 3-5: Determine whether or not the subject answers the direction of the break in the Landolt optotype via the answer switch 13 within the optotype presentation time, and whether the answer matches the cut in the Landolt optotype that was presented. CP[J607 determines whether or not the Judgment ′ is rYEsJ
If so, the process moves to step 3-6, and if the determination is rNOJ, the process moves to step 3-7.

Steps 3-6: The run and step Dort optotypes presented in step 3-4 are the minimum optotypes, i.e. 3-8
It is determined whether or not it is a Landolt optotype with visual acuity of 2.0, and if it is rYEsJ, the process moves to step 3-8, the official record ↑a that the visual acuity of the eye to be examined is 2.0 is stored in RAM60B, and then the next step 3 to 12. If the determination is 1NO, the process returns to step 3-4 and a Landolt optotype that is one step smaller than the previously presented optotype is presented. FIG. 12C is an example of presentation of the Landolt optotype for a visual acuity of 1.5. 1.0.1.2.1. The optotype 5.2.0 makes the corresponding Landolt optotype on the mask plate 423 observable by erasing not the Landolt optotype itself but the rectangular pattern 412a of the shutter line pattern.

Step 3-7: Since the determination of "No" was made in the previous step 3-5, cI) [J6 07 stores 1 in the failure number storage area of the RAM 608.

Already failed in the failure number storage area When the number N is memorized, Add 1 to it.

Step 3-9: Determine whether the number of failures N is 2 or not, and if step rYEsJ, step 33 "0"
The visual acuity value of the presented optotype immediately before the presented optotype for which the number of failures has become 2 is stored in the RAM 308 as the visual acuity of the eye to be examined, and the process then proceeds to the next step 3'2. If it is determined to be rNOj, the process returns to step 3-4 and presents an optotype that is one step smaller than the currently presented optotype.

Step 3 2: Execute the next inspection program.

For example, this screening is far-fetched. Visual acuity test (step 2-7) right eye test, the following The test program is the left eye test. Next light source 40■1.47R1 Pa Turn on Ilot lamp 315a Then, follow step 3 above. 3) Execute 2. Honsu The cleaning is a left eye exam. Binocular mode (switch 310) is selected, the next inspection will be for both Eye examination and light source 40R1401° Pilot lamp 315a.

Turn on 315b and the aforementioned Stella Execute step 3" or 3" 1 let Binocular examination is the main screening If it is a running test, the next step is The step becomes step 2-2.

In the distance visual acuity test, near visual acuity test, hyperopia check test, and pinhole check test described above, when astigmatism check is necessary, operate the astigmatism chart light switch 31) and the optical path selection switch 312 on the operation panel 30. The astigmatism chart can be presented to the patient at any time (even during the measurement).

FIG. 12D is an example of presenting an astigmatism table. The subject is asked to judge whether each meridian on the presented astigmatism chart can be seen with uniform shading. If there is a difference in shading depending on the direction of the meridian, ask students to verbally answer in which direction the meridian is dark (visible) using the ``time'' written on the meridian.

In this way, the present invention does not incorporate the astigmatism test into the measurement routine and allows the astigmatism test to be arbitrarily interrupted at any time during the measurement, so it has the advantage that the tester can perform the test whenever he or she suspects astigmatism. be.

In addition, if the test subject's answer, which is the basis for the judgment in step 3-2 above, is based on estimation rather than visual recognition, even if it is determined to be a correct answer, the flow in Figure 1) is 0. True visual acuity below .7 should not be accepted. As a countermeasure for this, step 3 added with a broken line in Figure 1I
-2b should be added. Step 3-2 b t:J
, I YES in step 3-2 as shown in Figure 13.
If it is determined as J, the user is asked to answer again by presenting the run i/rut optotype, which has the same visual acuity of 0.7 as the previous time but with a different cut direction from the previous optotype, until the number of correct answers Y reaches Y=2. The purpose of using an optotype with a cut in the Puno direction, which is different from the previous one, is to make it easier to detect the effects of astigmatism.

Further, when the number of correct answers Y becomes Y=2 not only in step 3-2 but also in tests using other visual acuity targets, the process proceeds to the next step. If it is desired to add a step for excluding measurements due to coincidence, the above-mentioned step 3-2b can be added after step 3-6.

In addition, the farsightedness check test performed by inserting the farsightedness test lens 491R1491L into the optical path, and the pinhole thousand nick test performed similarly by inserting the vinyl pole plate 493R14931 into the optical path are selected.
The test results of the distance visual acuity test stored in the CP and the test results of each test are stored in the CP 1. When the visual acuity value is compared with J607, the printer 19 is configured to print, for example, "Shiryoku Kojigo".

(310.7 precision test This 0.7 precision test is for conducting a visual acuity test for issuing an automatic driver's license. 7. Use the 7-point keyaki. That is, in the 0.7 precision test, first, step 4.
0.3 optotypes are displayed for the right eye in four directions, and it is determined whether or not a correct answer has been given for three or more directions. If a correct answer is given for three or more directions I- in Step 4, the process proceeds to Step 4-2.

In step 4-2, the 0.3 optotype for left Off is set to 4.
Directions are displayed, and it is determined whether or not a correct answer has been given for three or more directions. If a correct answer is given in step 4-2 for three directions or more, the process proceeds to step 4-3. In step 4-3, 0.7 optotypes are set to 4 for both INs.
The directions are displayed, and it is determined whether an IF answer has been made for three or more directions.

If correct answers are given in three or more directions in step 4-3, the process advances to step 4-4, where it is determined that the 0.7 precision test has passed, the pass judgment lamp 316a is lit, and step 4. 3 in any of 4-2.4-3
If the correct answer is not given for the direction or higher, proceed to step 4-5, where it is determined that the 0.7 precision test has failed.
Turn on the rejection judgment lamp 3] 6b.

Each step 4 in the flowchart of FIG. 14. The flow common to 4-2 and 4-3 consists of the following steps, as shown in FIG.

Step 5'': Reset the failure number N in the failure number storage area in the RAM 608 to 0. At the same time, the number of correct answers Y in the correct answer number storage area in the RAM 608 is also reset to zero. Since the measurement starts from the right eye (step 4), the light source 40R and the light source 471. lights up. Further, the CPIJ 607 recognizes that the transparent apertures 494R and 494T are located in the optical path by the ON signal from the claw 1-interrupter 501.

Step 5-2: CP[J607 determines the cut direction of the Landolt optotype from the last two digits of the currant value from CTC 609 at the time of transition to this step, and directs the visual acuity O13 (at step 4-3) to the cut direction of the Landolt optotype. Randall, whose visual acuity is 0.7) [presents optotype 403 (407). 0.3 or 0.7 is displayed on the liquid crystal panel 320.

This presentation of the Landolt optotype The eye direction is stored in RAM60B. let

Step 5-3: The CPU 607 determines whether the subject has answered within the optotype presentation time or whether the answer is correct. If the determination is rYEsJ, the process proceeds to step 5-4, and if the determination is rNOI, the process proceeds to step 5-5.

Step 5-4: Add 1 to the number of correct answers Y in the correct answer number storage area of the RAM 608 and store it again.

Step 5-5: Add 1 to the failure number N in the failure number storage area of the RAM 608 and store it again.

Step 5-6: The CPU 607 determines whether Y+N=4. That is, it is determined whether the Landolt optotype of 0.3 (or the optotype of 0.7 in the case of step 4-3) has been presented to the subject for all four types of breaks. When it is determined that the number of presentations Y+N is Y1N <4, the process moves to step 5-7.When the number of presentations is determined to be Y1N≧4, the process moves to step 5-8.

Step 5-7: A Landolt optotype having a cut direction other than the Landolt optotype stored in the RAM 608, that is, a cut direction that has not been presented yet, is presented. Then, the process returns to step 5-3 again.

Step 5=8: Determine whether the number of correct answers Y is Y≧3.

When Y≧3, it is judged as fail. and proceed to step 5"n. Immediately move to step 4-5, The judgment lamp 316b is turned on.

If the number of correct answers Y is Y≧3, Move to step 4-2 and connect to the left eye. Then repeat step 5. Execute step 5-8. If the current Execution step is step 4-3 In other words, 0 and 7 vision in binocular vision If it is a standard inspection step is based on the determination in step 5-9. and move on to step 4-4. Turn on the judgment lamp 316a Ru.

(4) Stereoscopic Test Stereoscopic Test 2''2 is composed of the following steps, as shown in FIG. 16.

Step 6”: The CPU 607 uses the driver circuit 602
Control L7, light a! Turn on X40R14 0L and turn off light source 47R1 47L. Next, the driver circuits 603 and 604 are controlled to open the shutter 413 at the position corresponding to the stereoscopic chart 416a of the parallax 4' of the mask plate 423 for the left and right eyes. 416a' is presented.

Figure 17 shows a stereoscopic view with a parallax of 4'. Chart image 416a' is presented. It shows the condition.

Step 6-2: The test subject uses the presented chart and
Among them, other diamonds step 6- by stereoscopic vision
4. Use the answer switch 13 to answer whether the diamond-shaped image 419', which appears to be floating above the image 418, is in the left, right, top, or bottom position. In the example of FIG. 17, the diamond on the left side appears to be floating, so the switch 21 is pressed. The CPU 607 compares the answer from the subject with the answer stored in advance in the ROM 606 and determines whether the answer is correct or not. If the answer is correct, proceed to step 6-3. If the answer is incorrect, the process moves to step 6-4, where the printer 19 prints out the discrimination ability with a parallax of 4' or more, that is, level 0, and the test ends.

Step 6-3: Similarly, stereoscopic vision with a parallax of 3' or maf with a yard of 416C and a parallax of 2' Step 6
5 The embodiment chart 416e, the stereoscopic chart t and 416b with a disparity of 1', and the stereoscopic chart 1416d with a disparity of 30" are presented in order according to whether the examinee's answer is correct, and the stereoscopic chart with the incorrect answer is Based on the parallax value of 1.1, it is determined that the level is either level 1 or level 4, and the result is printed by the printer 19.

If you press the end switch 313 on the operation panel 30 when you want to eliminate an erroneous test during any of the above-mentioned tests, the CPtJ607 will cancel the test after 1M and return to the initial state (Fig. 9). Return to step 1-2).

In addition, if a person who is taking a test using this vision meter for the first time does not understand how to answer, etc., there is a possibility that the test result may be incorrect.
Install the "1 practice" switch as shown by the broken line in Figure 3.
Each time this is turned on, a program is activated that presents a run-first visual target with visual acuity of 0.1 in a binocular continuous visual acuity test and allows the user to practice how to answer using the answer switch 13.

[Brief explanation of drawings]

FIG. 1 is an external perspective view showing an embodiment of an automatic sight word 1 according to the present invention, FIG. 2A is a plan view showing the configuration of an answer switch,
Figure 2B is a sectional view taken along nB-IIB' of Figure 2A;
Fig. 3 is a plan view showing the configuration of the operation panel, Fig. 4 is a perspective view showing the optical arrangement, Fig. 5 is a plan view showing the structure of the auxiliary lens group, and Fig. 6 is a plan view showing an example of the pattern of the liquid crystal plate. 7 is a plan view showing an example of a mask plate pattern, FIG. 8 is a block diagram showing the configuration of the electrical system, FIG. 9 is a flowchart showing the overall flow of the inspection routine, and FIG. 10 is a measurement processing subroutine. Figure 1) is a flowchart showing a screening routine, Figures +2A to 12D are diagrams showing examples of visual target presentation, Figure 13 is a flowchart showing a subroutine for preventing erroneous measurements due to chance-loss, and Figure 14 is a flowchart showing a screening routine. 0.7 A flowchart showing the precision test subroutine.
a flowchart showing the routine within that step of 1;
FIG. 16 is a flowchart showing a stereoscopic vision test routine, and FIG. 7 is a diagram showing an example of stereoscopic vision presentation. 10... Pedestal 1)... Operation panel 12... Start switch 13... Answer switch 19... Printer 30...・Operation panel 422R, 422L...Liquid crystal board 603...
...Dry halo 06...ROM 607...CPU 608...RAM To treetop 2 Figure 28 Figure 6 Figure 71"i Tension 419b 419d Figure 17 419cm 13th Waiting for Figure 3-4 Showa 62-27918 (19) Figure 16 Humming ■]

Claims (8)

[Claims] (1) In a method of selectively presenting a plurality of optotypes with different visual acuity values to a subject and automatically performing a visual acuity test based on whether the visual recognition of the optotypes is correct or incorrect, the visual acuity at a predetermined visual acuity value N is a first step of presenting a target; and a second step of asking the subject to visually recognize the target with the visual acuity value N;
stages; When the answer is "correct", the visual acuity value is higher than the visual acuity value N (
A third step in which an optotype with a visual acuity value of N+0.1) is then presented, and if the answer is "wrong", an optotype with a predetermined visual acuity value M (however, M<N) is presented next; High visual acuity value (N+n, n=0.2, 0.3,・
...or M+m, m=0.1, 0.2,..., N-
0.1) and a certain visual acuity value (N+n or M
+m) when the answer to the presented optotype is "wrong" multiple times, the visual acuity value of the optotype one step before the presented optotype is determined as the visual acuity of the subject; An automatic visual acuity testing method characterized by: (2) The automatic visual acuity testing method according to claim (1), wherein the visual acuity value N is 0.7. (3) The automatic visual acuity testing method according to claim (1) or (2), wherein the visual acuity value M is 0.1. (4) The automatic visual acuity testing method according to any one of claims (1) to (3), wherein the plurality of times in the fourth step is two times. (5) An optotype presenting means for selectively presenting a plurality of optotypes with different visual acuity values to the subject, and an answering means operated by the subject to give an answer corresponding to the presented optotypes. an automatic visual acuity comprising: a determining means for determining whether the answer from the answering means is correct; and a control means for controlling the optotype presenting means to present the next necessary optotype based on the determination result of the determining means. In the measurement, the control means first causes the optotype presentation means to present the index with a predetermined visual acuity N, and when the determination means determines that the answer from the answering means is "correct", the optotype The presenting means presents a visual acuity with a visual acuity value (N+0.1) higher than N, and when the determining means determines "wrong", the visual acuity of a predetermined M (M<N) is displayed on the visual target presenting means. After that, when the answer from the answering means is determined to be "correct", the visual acuity value (N+n, n=0) is sequentially higher than the previous one.
．． 2, 0.3, ... or M+m, m=0.1, 0.
2, .
Or, if the visual target (M+m) is judged as "wrong" multiple times, the visual acuity value N+n of the visual target presented immediately before that visual target
An automatic visual acuity meter characterized by controlling the visual acuity of a subject to be determined as -0.1 or M+m-0.1. (6) The automatic visual acuity meter according to claim (5), wherein the visual acuity value N is 0.7. (7) The automatic visual acuity meter according to claim (5) or (6), wherein the visual acuity value M is 0.1. (8) The automatic visual acuity meter according to any one of claims (5) to (7), wherein the plurality of "erroneous" determinations are made twice.