JP4406258B2 - Vision test device - Google Patents

Description

  The present invention relates to a visual acuity inspection apparatus that can be suitably used for driving aptitude inspection or the like.

In the driving aptitude test or the like, in addition to a normal static vision test, a moving body vision test is performed in order to check the degree of appearance of a moving object during driving of the vehicle (see Patent Document 1).
JP 2000-201893 A

  By the way, the appearance when driving a car is also affected by the effect of glare (glare light) caused by the headlight of an oncoming vehicle at twilight or at night and the degree of contrast between the surrounding background and the object. For this reason, in addition to the normal static visual acuity test, the visual acuity when moving visual acuity, glare light projection, and visual acuity when the contrast is changed are examined, and the subject is changed to a different visual environment. It is important to recognize the ability regarding visibility and to provide appropriate driving guidance.

  When these glare and contrast tests are performed in addition to the normal static vision test and dynamic vision test, the separate testing device will not only take time for the test, but also the concentration of the subject will be interrupted. There is a problem that affects accuracy, so a continuous device is desired. In addition, the conventional apparatus has a problem that it is difficult to create a state close to the actual change in the visual environment.

  In view of the above-described prior art, the present invention can recognize the visual ability of the subject with respect to the change of the visual environment in an easy-to-understand manner, and efficiently perform the visual examination in a state close to the actual change of the visual environment. It is an object of the present invention to provide a visual acuity inspection device that can be used.

In order to solve the above problems, the present invention is characterized by having the following configuration.
(1) Equipped with a target presentation optical system that can change the optical distance of the visual acuity test target to be presented to the subject's eye, inspecting the static eyesight of the subject's eye with the optical distance of the inspection target being a predetermined inspection distance, and inspection In the visual acuity inspection apparatus that inspects the moving body visual acuity of the eye to be examined by changing the optical distance of the visual target at a predetermined speed, the background luminance of the test visual target presented by the visual target presenting optical system is set to a high luminance of normal brightness Background luminance variable means for changing to a low luminance that reproduces a state that is difficult to see at night, and glare disposed at a position off the optical axis of the target presentation optical system in order to project glare light (glare light) to the subject's eye A glare light projecting means having a glare light source disposed at a position where the glare light is reflected directly or by a mirror and directed to the eye to be examined; and the background brightness varying means reduces the background brightness of the target. Set on the glare light Setting means capable of setting a static visual acuity test and a moving visual acuity test in which glare light is projected by the light projecting means.
(2) In the visual acuity test apparatus according to (1), the first visual acuity test target having a low transmittance and the first visual acuity test target arranged in the optical path of the visual target presenting optical system and having the low transmittance. A target selection means for selecting a second visual acuity test target whose transmittance is higher than that of the visual acuity test target; and the setting means sets the background luminance of the visual target to a low luminance and then the glare light projection In addition to glare light projection by the means, it is possible to set a static visual acuity test and a moving visual acuity test in which the second visual acuity test target is selected by the target selection means.

ADVANTAGE OF THE INVENTION According to this invention, the several visual acuity test | inspection which changed the visual environment can be performed efficiently , and the visual acuity ability at the time of a driving | operation can be test | inspected more appropriately.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an external view of a visual acuity test apparatus according to the present invention.

  Reference numeral 1 denotes an apparatus main body, and 2R and 2L are inspection windows for a subject to look into the apparatus and observe an inspection target presented in the casing by an optical system described later. An operation panel 3 having various switches for operation by an examiner is disposed on the side surface of the apparatus body 1.

  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 5 denotes a joystick for the subject to input the cut direction of the Landolt visual target to be presented, and reference numeral 4 denotes a response button for inputting the response when the presented visual target cannot be identified. In addition, the response button 4 also serves as a response input when the test target presented at the time of moving eyesight test can be determined. Reference numeral 6 denotes a switch for starting inspection in the automatic inspection mode. Reference numeral 9 denotes a speaker 9 that outputs a voice guide.

  A printer 8 prints out the inspection result. Reference numeral 10 denotes an open / close door, which includes a speed changeover switch for changing the apparent speed of the target moving at the time of moving visual acuity inspection, a switch for setting the contrast at the time of contrast inspection and the illumination brightness of the target, and the like. Is built-in. The moving speed of the visual target at the time of moving body vision test can be changed every 10 km / h between 20 and 60 km / h. The standard speed is usually set at 30km / h.

  FIG. 2 is a diagram seen from the side of the optical system of the apparatus and a configuration diagram of the main part of the control system. FIG. 3 is a view of the optical system as viewed from above. Reference numeral 11 is an illumination light source, 12 is a condenser lens, and 13 is a target plate. As shown in FIG. 4, the visual target plate 13 is provided with visual targets 40, 41, and 42 having different contrast ratios with respect to the background luminance. The target 40 has a contrast ratio of 100% (target transmission 0%), the target 41 has a contrast ratio of 10% (target transmission 90%), and the target 42 has a contrast ratio of 50. % (The transmittance of the visual target is 50%). The visual targets 40, 41, 42 are four Landolt ring visual targets each having a cut in the vertical and horizontal directions, and the sizes thereof are the same. In addition, the illumination light source 11 in the present apparatus uses a white LED that can change the amount of light (luminance), and the background luminance of the target can be changed. The optotype plate 13 is rotated by a motor 31 to switch the presentation optotype.

  The target on the target plate 13 is illuminated by turning on the illumination light source 11, and the target luminous flux from the target plate 13 is reflected by the prism 14 and the mirror 15, passes through the lens 16, and then reflects the mirror 17. Head to the lens 18. The target luminous flux that has passed through the lens 18 enters a prism 19, and is split into right and left optical paths by the prism 19. A mirror 20R and a mirror 20L are disposed in each of the divided optical paths, and the target luminous flux reflected by the mirror 20R and the mirror 20L passes through the protective glasses 22R and 22L disposed in the inspection window 2 to be covered. Head to the left and right of the optometry. In addition, half mirrors 21R and 21L are arranged in front of the left and right eye to be examined through protective glasses 22R and 22L, respectively. The glare emitted from the glare light source 25 is reflected by the half mirrors 21R and 21L and directed toward the eye to be examined. Two glare light sources 25 are provided with the optical axis sandwiched between the left and right optical paths, respectively. Note that the glare light source 25 may be arranged around the left and right examination windows 2R and 2L (protective glasses 22R and 22L), respectively, so as to directly irradiate the eye to be inspected with glare light.

  The prism 14 is moved by the moving device 32 and can optically change the distance between the eye to be examined and the visual target from 50 m to 3 m. The size of the visual target on the visual target plate 13 is such that when the distance between the eye to be examined and the visual target is 50 m, the visual acuity value is 1.66, when the distance is 30 m, the visual acuity value is 1.0. It is designed to be 1. In addition, when performing a one-eye examination, shutters (not shown) are respectively inserted on the optical paths in front of the left and right protective glasses 22R and 22L.

  Reference numeral 30 denotes a control unit. The control unit 30 stores inspection programs such as a normal static visual acuity test, a moving visual acuity test, a contrast test, and a glare test, and the illumination light source 11 and the glare light source 22 are turned on / off, the motor 31, The operation of the moving device 32 and the voice guide generator 33 is controlled. The control unit 30 is connected to the panel unit 3, the response button 4, the joystick 5, the memory 34 for storing measurement results, the printer 8, and the input device 35 for age input. The input device 35 includes a numeric keypad 35a for inputting the age numerically and a display unit 35b for displaying the age.

  FIG. 5 is a configuration diagram of the operation panel 3. Reference numeral 100 denotes an inspection mode selection switch. The inspection mode includes an automatic inspection mode in which the subject can proceed with the inspection by operating the switch according to the voice guide, a manual inspection mode in which the inspector advances the inspection by operating each switch, instructions for the inspection procedure, There are three types of semi-automatic inspection modes in which the conditions are set by the apparatus and the inspection is performed by the examiner inputting only the response of the subject.

  Reference numeral 101 denotes a switch for selecting an eye to be examined (left, right, both eyes) to be examined. Reference numeral 102 denotes a switch for starting a static visual acuity test at normal brightness, 103 a switch for starting a moving visual acuity test, 104 a switch for starting a contrast test, and 105 a switch for starting a glare test. The switches 102 to 105 are used when performing individual inspections in the manual mode.

  Reference numeral 110 denotes a visual value display, and reference numeral 111 denotes a visual value selection switch. Reference numeral 115 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. A switch 106 is used by the examiner to input that the reading is impossible. A print switch 38 prints out the inspection result.

  Next, a normal visual acuity test, a static visual acuity test, a moving visual acuity test, a contrast test, and a glare test, which are performed by the apparatus having the above configuration, will be described. Here, a case where each inspection is continuously performed by using the automatic inspection mode will be described.

  When the switch 6 is pressed, a normal stationary visual acuity test is started first. Under the control of the control unit 30, any one of the visual targets 40 (high contrast visual targets) of the visual target plate 13 is arranged in the visual target presenting optical path, and the illumination light source 11 is turned on. The background luminance of the target is set to 200 cd / cm2. Further, the optical target presentation distance is adjusted by moving the prism 14 so that the visual acuity value of the first target is 0.5. The subject responds with the joystick 5 with the result of the target discrimination. When the target cannot be identified, a response is made with button 4. The control unit 30 determines whether the direction in which the joystick 5 is tilted with respect to the presented target is correct. If the answer is correct, the prism 14 is moved to increase the visual acuity value by one level (the visual acuity value is 0.6). When the response is an incorrect answer (including a response indicating that it cannot be determined), the visual acuity value is lowered by one step (the visual acuity value is 0.4). If there is a wrong answer at the stage of increasing the visual acuity value, the visual acuity value of the visual target is returned to the visible stage and the direction of the visual target is changed. If there are two or more correct answers with the same visual acuity value, the control unit 30 has the visual acuity value. The static visual acuity value is stored in the memory 34.

  Then, it moves to a dynamic visual acuity test. The control unit 30 moves the prism 14 so that the optical presentation distance of the visual target (target 40) is set to 50 m (visual acuity value 1.6), and then is applied to the eye to be examined at an apparent speed of 30 Km / h. Move closer. The cut direction of the target is determined randomly. The subject presses the response button 4 when the target is readable. The control unit 30 stops the movement of the target and simultaneously turns off the illumination light source 11 to make the target invisible. The subject responds to the cut direction of the target by operating the joystick 5. The control unit 30 determines the correctness based on the response input from the joystick 5. The moving object visual acuity value is calculated based on the position of the visual target when the response button 4 responds. The moving body vision test is repeated until the correct answer is obtained five times.

  Subsequently, the contrast inspection is started. The target used in the contrast inspection can be selected in advance by a switch inside the opening / closing door 10. Here, it is assumed that a low-contrast visual target 41 is set. The background luminance of the target is set to 200 cd / cm @ 2 as in the normal static vision test. The control unit 30 drives the motor 31 to place one of the low-contrast visual targets 41 in the visual target presenting optical path. By presenting the low-contrast visual target 41, the visual acuity test is started in the same manner as the static visual acuity test. First, the prism 14 is moved so that the visual acuity value of the visual target becomes 0.5, and then the subject is asked to respond with the joystick 5 or the button 4 that the determination result cannot be read. The control unit 30 changes the visual acuity value of the visual target based on whether the response is correct or incorrect. If there are two or more correct answers with the same visual acuity value, it is assumed that there is the visual acuity value. The low contrast visual acuity value is stored in the memory 34.

Next, the glare inspection is started. In the glare inspection, any one of the visual targets 40 is again arranged in the visual target presenting optical path and the glare light source 25 is turned on under the control of the control unit 30. When the glare light source 25 is turned on, the correctness / incorrectness of the response content of the subject is determined by the control unit 30 and the visual acuity value is inspected in the same manner as in the normal stationary visual acuity test described above.
When the glare inspection is completed, the voice guide announces the end of the inspection, and the printer 8 outputs the inspection result.

  FIG. 6 is a diagram showing an example of printout of the inspection result. In the examination result column, a normal static vision result 201, a moving object vision test result 202, a contrast test (a visual acuity value in a low-contrast test of 10% here) result 203, a glare test result 204, and a driving result The instruction content 205 is displayed. Below the result 203 of the contrast inspection, an evaluation 210 for the contrast inspection is displayed. In this evaluation 210, the difference between the visual acuity value obtained by the static visual acuity test and the visual acuity value obtained by the contrast test is calculated by the control unit 30, and is classified into five stages based on the difference. For example, as shown in FIG. 7, the difference in visual acuity is “0.1 or less”, “0.2”, “0.3”, “0.4”, “0.5 or more”, "5 (excellent)", "Evaluation 4 (slightly superior)", "Evaluation 3 (normal)", "Evaluation 2 (slightly inferior)", "Evaluation 1 (inferior)" The five-stage relative evaluation value for the static visual acuity is determined by the control unit 30.

  Below the result 204 of the glare test, a glare test evaluation 212 classified into five levels is displayed based on the difference between the visual acuity value obtained by the static visual acuity test and the visual acuity value obtained by the glare test. Has been. This evaluation 212 is also determined according to the table of FIG. 7 in the same manner as the calculation method of the contrast inspection evaluation 210. Regarding the moving visual acuity, an evaluation classified into five levels based on the difference from the visual acuity value of the static visual acuity may be displayed. Since the change in the visual acuity value when the visual environment changes is expressed in an easy-to-understand manner, even an elderly subject can easily recognize the degree of his / her visual ability. The guidance content 205 displays precautions for changes in the visual environment during driving of the vehicle based on the evaluation and the visual acuity value of each examination.

The classification of the evaluation based on the difference in the static visual acuity of each examination may be determined by statistically processing from the results of examining a large number of subjects. Moreover, since the ability of appearance changes with age, the evaluation may be calculated by statistical processing for each age. The age of the subject is input by the input device 35 before starting the test. The evaluation result is an evaluation classified into five levels for the same age group. For example, if the age of the subject is an age group of 50 to 59 years old, the evaluation result is expressed as being higher / lower than the average of 50 to 59 years old.
Further, in the dynamic visual acuity test, the contrast test, and the glare test, the visual ability may be classified into five levels based on the results of the respective visual acuity tests, and evaluation may be added.

In the contrast inspection and the glare inspection in the above embodiment, the background luminance of the target is the same as that in the normal static visual acuity inspection. However, by adjusting the light amount of the illumination light source 11, for example, 10 cd / cm ² is difficult to see at night. By changing to a visual environment that reproduces, the visual acuity during driving can be more appropriately examined. Furthermore, if a target 42 having a contrast ratio of 50% is used instead of the low contrast target 41, the visual environment when an object with poor contrast is viewed at night or the like can be easily reproduced.
In addition, the target presentation with different contrasts may be performed by changing only the background luminance of the target by adjusting the light amount of the illumination light source 11 (contrast inspection is also included in this case).
Further, the glare light projection and the change in the contrast of the presented visual target may be performed at the time of moving visual acuity examination. In the driving aptitude test, it is possible to provide guidance and advice on a more appropriate driving method of the vehicle by performing a visual acuity test in various changes in the visual environment.

  In the above embodiment, the glare light is simply inserted into the optical path of the inspection target. However, the present invention is not limited to this. It may be configured such that the glare light source is projected from a distance farther than the actual distance apparently with respect to the eye to be examined.

  FIG. 8 is a diagram illustrating an optical system configured to project a glare light source from a position that is apparently separated from the eye to be examined by a predetermined distance (here, approximately 30 m) (similar to FIG. 3, the optical system is viewed from above). It is a view). In the figure, components having the same functions as those shown in FIG. The other optical members and the control system are basically the same as those shown in FIG.

  Reference numerals 50R and 50L denote glare light sources, which are arranged at positions that are not optically affected by the prism 14 shown in FIG. 2, as shown in FIG. Although the glare light sources 50R and 50L can be installed in the vicinity of the target plate 13, if a glare light source is installed in the vicinity of the target plate 13, the glare light source is moved by the movement of the prism 14 at the time of moving body inspection. However, it is difficult to perform a high-precision glare test because it approaches the eye to be examined together with the visual target. Therefore, it is preferable that the glare light sources 50R and 50L are disposed at positions that are not optically influenced by the prism 14 as described above.

  51R and 51L are mirrors for returning the light beams from the glare light sources 50R and 50L to enter the prism 19, respectively. The mirror 51R and the mirror 51L are installed so as to sandwich the target luminous flux directed to the prism 19 after being reflected by the mirror 17 from both sides. The installation interval between the mirror 51R and the mirror 51L is an interval through which all the target luminous flux reflected by the mirror 17 passes and does not block the target luminous flux. In addition, after the luminous fluxes emitted from the glare light sources 50R and 50L are reflected by the mirrors 51R and 51L, the glare light sources 50R and 50L are installed on the mirrors 51R and 51L in order to allow as much illumination light quantity as possible to enter the prism 19. The angle has been adjusted.

  52R and 52L are lenses for projecting the inspection target on the left and right eyes, respectively, instead of the lens 18 of FIGS. 2 and 3, and mirrors 20 and 20L and protective glasses 22R disposed on the left and right optical paths, respectively. It is placed between 22L. At the same time, the lenses 52R and 52L also serve as projection lenses for projecting the glare light sources 50R and 50L onto the eye to be examined. The installation positions of the glare light sources 50R and 50L are located closer to the subject's eye than the focal positions of the lenses 52R and 52L. As a result, the glare light source 50R and the glare light source 50L appear to be projected from a position far away from the actual distance with respect to the eye to be examined. In this embodiment, the apparent projection distance is set to 30 m. However, the projection distance is not limited to this, and the projection distance of the glare light source (50R, 50L) necessary for performing the glare inspection more accurately is infinite. Any optical design that can secure a distance (for example, 5 m to 50 m, etc.) that can be considered as long as possible can be used.

  In addition, since the glare light sources 50R and 50L are placed at positions away from the optical axis of the target luminous flux as shown in the figure, the more the lenses 52R and 52L move away from the eye to be examined, the more glare light is incident on the eye to be examined. The deviation of the luminous flux (the deviation of the target luminous flux from the optical axis) becomes large. As a result, the glare light projected on the eye to be examined is scattered by the optical wall in the middle and the outer walls around the protective glasses 22R and 22L, and the beam diameter of the glare light incident on the eye to be examined becomes small due to the deviation of the light flux. Or it may disappear completely. For this reason, the lenses 52R and 52L for projecting the glare light sources 50R and 50L onto the eye to be examined are located as close as possible to the eye to be examined, in other words, as much as possible in the examination windows 2R and 2L where the protective glasses 22R and 22L are located. It is preferable to arrange them close to each other.

  The glare inspection in the apparatus having the above optical system configuration will be described. Under the control of the control unit 30 shown in FIG. 2, any one of the visual targets 40 is arranged in the visual target presenting optical path, and the glare light sources 50R and 50L are turned on. The glare luminous fluxes emitted from the glare light sources 50R and 50L are reflected by the mirrors 51R and 51L, respectively, and enter the prism 19 together with the target luminous flux. Thereafter, the target luminous flux and the glare luminous flux are divided into the left and right optical paths, and go through the mirrors 20R and 20, the lenses 52R and 52L, and the protective glasses 22R and 22L to the left and right eyes, respectively. Since the subject can inspect while looking at the glare light source projected from the front 30 m on both sides of the target image presented at a predetermined distance, it is possible to obtain a state more suitable for the actual situation. It is possible to perform a glare inspection with high reliability. The same applies to the single eye examination.

  In the optical system shown in FIG. 8, the lenses 52R and 52L arranged in the vicinity of the protective glasses 22R and 22L are shared for both the presentation of the target and the projection of the glare light source. It is not a thing. For example, a projection lens may be disposed between the glare light source 25 and the half mirror 21R (21L) shown in FIG.

It is an external view of the visual acuity test | inspection apparatus which concerns on this invention. It is the figure seen from the side of the optical system of an apparatus, and the principal part block diagram of a control system. It is the figure which looked at the optical system from the top. It is a figure which shows the target structure in which the target plate was formed. It is a block diagram of an operation panel. It is a figure of the example of print output of a test result. It is a figure which shows the evaluation of five steps based on the difference of a visual acuity value. It is the figure which showed the optical system for making it appear as if it projected from a distant place glare light source.

Explanation of symbols

8 Printer 11 Illumination light source 13 Target plate 40, 41, 42 Target 14 Prism 19 Prism 21R, 21L Half mirror 25 Glare light source 30 Control unit 31 Motor 32 Moving device 40, 41, 42 Target 203, 212 Evaluation

Claims (2)

Equipped with an optotype presenting optical system that can change the optical distance of the visual acuity test target to be presented to the eye to be examined, the static visual acuity of the eye to be examined is inspected by setting the optical distance of the test eye to a predetermined inspection distance, In the visual acuity inspection device that inspects the moving body visual acuity of the subject's eye by changing the optical distance at a predetermined speed, the background luminance of the inspection target presented by the visual target presenting optical system is high in normal brightness and difficult to see at night A background luminance variable means for changing the state to a low luminance that reproduces the state, and a glare light source disposed at a position off the optical axis of the target presentation optical system in order to project glare light (glare light) to the eye to be examined. The glare light projecting means having a glare light source arranged at a position where the glare light is reflected directly or reflected by the mirror and directed to the eye to be examined, and the background brightness varying means sets the background brightness of the target to a low brightness. On the glare light projector Vision testing apparatus, characterized in that it comprises a setting means capable of setting a static vision was projected glare light inspection and dynamic visual acuity test, the by. The visual acuity test apparatus according to claim 1, wherein the visual acuity test target has a different transmittance and is arranged in an optical path of the visual target presenting optical system, and the first visual acuity test target having a low transmittance and the first visual acuity test visual A target selecting means for selecting a second visual acuity test target whose transmittance is higher than that of the target, and the setting means sets the background brightness of the target to a low brightness and then glare by the glare light projecting means. A visual acuity test apparatus capable of setting a static visual acuity test and a moving visual acuity test in which the second visual acuity test target is selected by the target selection means in addition to light projection.

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