JP2006263067A - Optometer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optometer capable of measuring visual acuity in each distance range and highly precisely measuring the visual acuity. <P>SOLUTION: A display device 3 is moved in the X direction by a driving device 4 and an input device 6 inputs whether a subject 1 can identify an image for an optometry on the display device 3. In this case, the display size of the image for the optometry is changed according to a distance between the position of an eye of the subject 1 and the position of the display device 3 displaying the image for the optometry so as to be projected on the retina of the subject 1 at a fixed size according to the set visual acuity. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a visual acuity measuring apparatus for measuring the visual acuity of a subject.

  In the conventional visual acuity measurement, in the case of myopia, a table displaying a plurality of large and small C-shaped Landolt rings at a distance of 5 m from the subject is installed, and the visual acuity is determined with a size that can identify the breaks in the Landolt ring. Measuring. In the case of hyperopia, a table displaying the Landolt ring is placed at a distance of 50 cm from the subject, and the visual acuity is measured in a size that can identify the breaks in the Landolt ring.

  FIG. 8 is a diagram showing a visual acuity measurement operation using the Landolt ring. As shown in the figure, the visual acuity value is represented by 1 / viewing angle (minute). The direction of the Landolt ring used for the measurement is four directions, up, down, left and right.

  FIG. 9 is a diagram showing an image of conventional visual acuity measurement, and shows the relationship between distance and visual acuity. As shown in the figure, the visual acuity originally depends on the distance and can change continuously. The three subjects of the measurement data A, B, and C have different visual acuity, but all of the current measurement methods are judged to be the same. Thus, the conventional visual acuity by measuring only two points at different distances is insufficient, and more accurate visual acuity measurement is necessary to determine training conditions such as visual acuity recovery training.

  It is also known to use an accomodometer for measuring visual acuity (see, for example, Non-Patent Document 1). This measures the time it takes to focus from the point that is closest to the eye (near point) to the point that is farthest (far point), or vice versa. The apparatus measures objectively the refraction value of the subject when the fixation target is moved continuously with a built-in refractometer. At that time, an adjustment stimulus is given by moving the position of the fixation target, and the adjustment reaction is measured by an automatic refractometer.

  There has also been proposed a vision improvement device that facilitates focusing of eyes when moving a target such as a Landolt ring (see, for example, Patent Document 1). This moves the target at an appropriate speed between a near point and a far point at a predetermined distance from the eyepiece, and is displayed on the target in proportion to the distance between the target and the eyepiece. It changes the size of the figure.

Toshio Maruo and Shinobu Ashiya "Vision Correction" 7th edition, Kanehara Publishing Co., Ltd., published February 10, 2004, pages 113-114 International Publication No. 2004/066900 Pamphlet

  However, in the conventional visual acuity measuring device, the relationship between the distance to the table for visual acuity measurement and visual acuity is not considered so much, so an erroneous visual acuity judgment may be made, and the conditions such as visual acuity recovery training are accurate. There was a case that could not be set.

  The present invention has been made in view of the above-described conventional circumstances, and it is an object of the present invention to provide a visual acuity measuring apparatus that can measure how much visual acuity is in a range of distances and can perform high-accuracy visual acuity measurement. And

  The visual acuity measurement device of the present invention is a visual acuity measurement device for measuring the visual acuity of a subject, a visual acuity setting unit that sets a visual acuity value to be measured, a display unit that displays an image for visual acuity measurement, and the subject's visual acuity A drive unit that changes the distance between the position of the eye and the position of the display unit, and the visual acuity measurement image on the retina of the subject according to the distance, a constant size according to the set visual acuity value A display control unit that changes a display size of the visual acuity measurement image so as to be projected.

  According to the above configuration, the subject is informed of whether or not the eyesight measurement image can be identified while changing the distance between the position of the display unit that displays the eyesight measurement image according to the set eyesight value and the eye position of the subject. By doing so, it is possible to measure at what distance the eye has the visual acuity to be measured. That is, it is possible to measure how much visual acuity is in which distance range, and it is possible to measure visual acuity with high accuracy. Therefore, conditions such as visual acuity recovery training can be set accurately.

  In addition, the visual acuity measuring device of the present invention includes an input unit for inputting a discrimination result of the visual acuity measurement image by the subject. According to the above configuration, the visual acuity measurement result can be automatically obtained using the input discrimination result.

  In the visual acuity measuring apparatus of the present invention, the discrimination result includes information indicating the direction of the visual acuity measurement image. According to the said structure, visual acuity can be measured more correctly.

  In the visual acuity measuring apparatus of the present invention, the input unit includes a voice input unit and a voice recognition unit that recognizes the input voice. According to the said structure, a discrimination | determination result can be input with a test subject or the voice of the person around a test subject.

  In addition, the visual acuity measuring device of the present invention includes a distance information output unit that outputs information on the distance between the eye position of the subject and the position of the display unit at the time when input is performed on the input unit. According to the said structure, a test subject can be made to grasp | ascertain distance by displaying the acquired distance information on a display part, or outputting with an audio | voice.

  In the visual acuity measuring apparatus according to the present invention, the display unit is a liquid crystal display panel. According to the above configuration, it is possible to display a vision measurement image with low power consumption.

  In the visual acuity measuring apparatus of the present invention, the drive unit moves the display unit from a position where the subject cannot discriminate the visual acuity measurement image to a position where the visual acuity measurement image can be discriminated. According to the above configuration, when the display unit is moved from a discriminable position to an indistinguishable position, it is difficult for the subject to accurately recognize whether he / she can discriminate the image for measuring eyesight. On the other hand, the subject can easily recognize whether or not discrimination is possible, and can accurately report it, thereby enabling more accurate visual acuity measurement.

  In the visual acuity measuring device of the present invention, when the subject is a nearsighted person, the drive unit moves the display unit in a direction to approach the subject. According to the above configuration, the subject can easily recognize whether or not discrimination is possible, and can accurately report it, thereby enabling more accurate visual acuity measurement.

  In the visual acuity measuring device of the present invention, the drive unit moves the display unit in a direction away from the subject when the subject is a farsighted person. According to the above configuration, the subject can easily recognize whether or not discrimination is possible, and can accurately report it, thereby enabling more accurate visual acuity measurement.

  In addition, the visual acuity measuring apparatus of the present invention has a visual acuity recovery training mode for performing an eye imaging adjustment function training, and in the visual acuity recovery training mode, the display unit displays an image for training, and the driving unit The display unit continuously reciprocates, and the display control unit sets the training image on the retina according to the distance between the eye position of the subject and the position of the display unit. The display size of the training image is changed so as to be projected at a certain size according to the visual acuity value. According to the said structure, the effect of a vision recovery training can be measured.

  According to the present invention, according to the distance between the position of the eye of the subject and the position of the display unit of the image for measuring eyesight, the image for measuring eyesight has a constant size according to the eyesight value set on the retina of the subject. To provide a visual acuity measuring apparatus capable of measuring the visual acuity at a certain distance range by changing the display size of the visual acuity measurement image so as to be projected, and capable of measuring the visual acuity with high accuracy. it can.

  Hereinafter, a visual acuity measuring apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram showing a schematic configuration of a visual acuity measuring apparatus according to an embodiment of the present invention. In the figure, reference numeral 1 denotes a subject who performs visual acuity measurement, and shows a state in which the face is directed to the eyepiece of the visual acuity measurement apparatus 2. The visual acuity measuring device 2 measures the visual acuity of the subject, a visual acuity setting device (not shown, described later) for setting a visual acuity value to be measured, a display device 3 for displaying an image for visual acuity measurement, and the subject 1 The eyesight measurement image is on the retina of the subject 1 in accordance with the distance between the eye position of the subject 1 and the position of the display device 3. And a control device 5 that changes the display size of the image for visual acuity measurement so that the image is projected at a constant size according to the set visual acuity value. The drive device 4 moves the display device 3 in the X direction in the figure.

  The display device 3 and the driving device 4 are controlled by the control device 5. Further, an input device 6 having a switch or the like for inputting a discrimination result of the visual acuity measurement image by the subject 1 is provided in the vicinity of the eyepiece portion of the visual acuity measurement device 2, and the visual acuity measurement result is automatically obtained. Be able to.

  FIG. 2 is a diagram illustrating an example of a visual acuity measurement image of the display device 3. The display device 3 is composed of a liquid crystal display panel capable of displaying the visual acuity measurement image 7 with low power consumption. Here, a case where a C-shaped mark (Landolt ring) is displayed on the visual acuity measurement image 7 is shown, and the discrimination result of the visual acuity measurement image 7 input from the input device 6 is the visual acuity measurement image. 7 includes information indicating the direction of 7 (the direction of the break of the mark). (A) of the figure shows the case where the distance between the eye position of the subject 1 and the position of the display device 3 is short, and (b) shows the case where the distance is long.

  FIG. 3 is a block diagram showing the configuration of the control device 5 and the input device 6 of the present embodiment. In addition to the switch 11 described above, the input device 6 includes a visual acuity value setting unit 12 that sets a visual acuity value to be measured. In addition, the input device 6 is provided with a voice input unit 13 for inputting voice and a voice recognition unit 14 for recognizing the input voice, and inputs a discrimination result by the voice of the subject 1 or a person around the subject 1. Can be done. Further, a distance information output unit 15 that outputs information on the distance between the position of the eye of the subject 1 and the position of the display device 3 at the time when the input is performed on the input device 6 is provided, and the acquired distance information is displayed on the display device. 3 is configured such that the subject 1 can grasp the distance by displaying it on the screen 3 or outputting it by voice.

  The control device 5 is provided with a control input unit 21 for inputting control information from the input device 6, and the display control unit 22 for changing the display size of the above-described visual acuity measurement image through the control input unit 21 and a driving device. 4 is controlled. Further, a moving direction control unit 24 that controls the moving direction of the display device 3, a position control unit 25 that controls the position, and a speed control unit 26 that controls the speed are provided, and the display device 3 is connected to the subject 1 by the driving device 4. However, the visual acuity measurement image 7 can be moved from a position where it cannot be determined to a position where it can be determined.

  When the subject 1 is a nearsighted person, the display device 3 is moved in a direction to approach the subject 1, and when the subject 1 is a farsighted person, the display device 3 is moved in a direction away from the subject 1. When the display device 3 is moved from a discriminable position to an indistinguishable position, it is difficult for the subject 1 to accurately recognize whether he / she can discriminate the visual acuity measurement image 7 or not. 1 makes it easy to recognize whether or not discrimination is possible, and since it can be accurately reported, more accurate visual acuity measurement is possible.

  Furthermore, the visual acuity measuring apparatus according to the present embodiment has a visual acuity recovery training mode for training the imaging adjustment function of the eyes. In this visual acuity recovery training mode, the display device 3 displays an image for training. The driving device 4 continuously reciprocates the display device 3, and the display control unit 22 displays the training image on the retina according to the distance between the eye position of the subject 1 and the position of the display device 3. The display size of the training image is changed so as to be projected at a constant size according to the visual acuity value set by the visual acuity value setting unit 12. Thereby, the effect of vision recovery training can be measured.

  According to this embodiment, the subject 1 uses the eyesight measurement image 7 to change the distance between the position of the display device 3 that displays the eyesight measurement image 7 corresponding to the set eyesight value and the eye position of the subject 1. By reporting whether or not the image 7 can be discriminated, it is possible to measure at what distance the eye has the visual acuity of the measurement object. That is, it is possible to measure how much visual acuity is in which distance range, more accurate visual acuity measurement is possible, and conditions such as visual acuity recovery training can be set accurately.

  Next, the operation at the time of visual acuity measurement in the present embodiment will be described. When measuring visual acuity, a C-shaped mark shown in FIG. 2 is used as a visual target to be displayed on the visual acuity measurement image 7. In this case, as shown in FIG. 8, the visual acuity value is represented by 1 / viewing angle (minute). The direction of the mark used for measurement is four directions, up, down, left and right.

  Actual measurement is performed by slowly moving the display device 3 while displaying a mark corresponding to the set visual acuity value (image for visual acuity measurement). At this time, according to the distance between the eye position of the subject 1 and the position of the display device 3, the image for visual acuity measurement is projected onto the retina of the subject 1 with a certain size according to the set visual acuity value. The display size of the image for visual acuity measurement is changed. The subject 1 presses the switch 11 corresponding to the direction of the cut when the direction of the mark is visible. At this time, if the pressed direction matches the displayed direction, the distance is stored. If the answer is incorrect, the action (redo or continue) is performed according to the settings.

  Then, the number of times set with the same visual acuity value is measured, and after all the visual acuity measurements are performed, the measurement result is displayed and a file is created. The display format of the measurement result is visual acuity value-distance (average value), and the file format is visual acuity value: distance, ... distance (repeated by the number of times of measurement). The file name is the date and time (up to seconds). For example, when a USB memory is inserted, the file is automatically copied, erased from the storage, and executed until the USB memory is released.

  Thus, in the present embodiment, the display size of the mark is changed at the same time as the position of the display device 3 is changed. For example, in the measurement of myopia, when the display device 3 is brought closer from a distance while displaying a mark corresponding to a visual acuity of 0.5, it can be determined at a position of 3 m. Next, it is assumed that the same measurement is performed while displaying a mark corresponding to a visual acuity of 0.7, and the discrimination can be made at a position of 2 m. By performing this from a visual acuity value of about 0.1 to about 1.5, accurate visual acuity can be measured.

  As another method, the display device 3 is fixed at a position 30 cm from the subject 1, and a mark having a size equivalent to visual acuity 2.0 is displayed on the display device 3. Then, the mark is continuously increased, and when the subject 1 can be determined, the direction of the mark is input. At this time, if the direction of the mark is different, a buzzer is sounded, the size of the mark is continuously increased as it is, and if the direction of the mark is correct, a “ping-pong” is sounded and a flower circle is displayed.

  Next, the display device 3 is moved to a position of 1 m, and the visual acuity measurement is similarly performed. This is repeated up to a certain distance, for example, 5 m. At that time, the size of the mark to be displayed may be started from one smaller than the size determined in the previous measurement. In this case, the measurement time can be shortened. In the case of a farsighted person, it is more reasonable to move the position of the display device 3 from the far side to the closer side.

  FIG. 4 is a diagram showing an image of visual acuity measurement in the present embodiment. The above-described measurement method enables accurate visual acuity measurement.

  FIG. 5 to FIG. 7 show the visual acuity measurement results in the present embodiment. FIG. 5 shows a case of myopia, FIG. 6 shows a case of hyperopia, and FIG. 7 shows a case where amblyopia is suspected. It is the range where the lower part of the graph of each figure can be seen. For example, in FIG. 5, the visual acuity is 0.7 when the distance between the eye position of the subject and the position of the display device is 0 to 1.0 m, and the visual acuity is 0.00 when the distance is 0 to 0.75 m. It turns out that it is eight. In this way, for each of myopia, hyperopia and amblyopia, it is possible to accurately measure how much visual acuity is in which distance range.

  Here, whether or not the subject 1 has been able to determine the mark may be reported by the subject 1 inputting his / her voice, or may be reported by the voices of the surrounding people who have heard the subject's voice. Further, a method of pressing the above-described switch 11 or the like may be used. By reporting the direction of the mark break, it is possible to perform visual acuity measurement more accurately. At that time, by changing the contrast of the mark to be displayed, it is possible to easily detect a reduction in visual acuity due to an ocular abnormality such as a cataract. Further, by performing the same measurement immediately after waking up and after work, it is possible to measure a reduction in visual acuity due to eye fatigue.

  As a means for inputting the discrimination result of the visual acuity measurement image, a joystick that performs a switch operation can be used in addition to the above method. Moreover, the moving speed of the display apparatus 3 should just be a grade which the test subject 1 can track the movement.

  Further, if the discrimination result inputted by the subject is different, a buzzer may be sounded, and if it matches, a “ping pong” may be sounded to display a flower circle.

  In the above description, the distance between the eye position of the subject 1 and the position of the display unit of the visual acuity measurement image 7 is described as an example of a linear distance. However, an optical distance using a reflecting mirror or the like is described. It can be implemented in the same manner even if the value is changed.

  According to the present invention, the visual acuity measurement image is projected at a certain size according to the visual acuity value set on the retina of the subject according to the distance between the eye position of the subject and the position of the display unit of the visual acuity measurement image. Thus, by changing the display size of the image for visual acuity measurement, it is possible to measure how much visual acuity is in which distance range, and it is possible to measure the visual acuity with high accuracy. It is useful for a visual acuity measuring device or the like.

The figure which shows schematic structure of the visual acuity measuring apparatus of embodiment of this invention. The figure which shows an example of the image for a visual acuity measurement of the display apparatus in embodiment of this invention The block diagram which shows the structure of the control apparatus and input device in embodiment of this invention The figure which shows the image of the visual acuity measurement in embodiment of this invention The figure which shows the visual acuity measurement result in the case of myopia in embodiment of this invention The figure which shows the visual acuity measurement result in the case of hyperopia in embodiment of this invention The figure which shows the visual acuity measurement result when the amblyopia is suspected in embodiment of this invention Diagram showing visual acuity measurement using a Landolt ring A diagram showing an image of conventional visual acuity measurement

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Test subject 2 Visual acuity measurement apparatus 3 Display apparatus 4 Drive apparatus 5 Control apparatus 6 Input apparatus 7 Image for visual acuity measurement 11 Switch 12 Visual acuity value setting part 13 Voice input part 14 Voice recognition part 15 Distance information output part 21 Control input part 22 Display control Unit 23 Drive control unit 24 Movement direction control unit 25 Position control unit 26 Speed control unit

Claims (10)

A visual acuity measuring device for measuring a visual acuity of a subject,
A vision setting unit for setting a vision value to be measured;
A display unit for displaying an image for measuring eyesight;
A drive unit for changing a distance between the position of the eye of the subject and the position of the display unit;
Display control for changing the display size of the visual acuity measurement image according to the distance so that the visual acuity measurement image is projected on the retina of the subject with a constant size according to the set visual acuity value. And
A visual acuity measuring device comprising: The visual acuity measuring device according to claim 1,
A visual acuity measuring apparatus comprising an input unit for inputting a discrimination result of the visual acuity measurement image by the subject. The visual acuity measuring device according to claim 2,
The visual acuity measurement apparatus, wherein the discrimination result includes information indicating a direction of the visual acuity measurement image. The visual acuity measuring device according to claim 2 or 3,
The visual acuity measuring apparatus, wherein the input unit includes a voice input unit and a voice recognition unit that recognizes the input voice. The visual acuity measuring device according to any one of claims 2 to 4,
A visual acuity measuring device comprising a distance information output unit that outputs information on a distance between the eye position of the subject and the position of the display unit at the time when input is performed on the input unit. The visual acuity measuring device according to any one of claims 1 to 5,
The visual acuity measuring apparatus, wherein the display unit is a liquid crystal display panel. The visual acuity measuring device according to any one of claims 1 to 6,
The drive unit is a visual acuity measurement apparatus that moves the display unit from a position where the subject cannot discriminate the visual acuity measurement image to a position where the image can be determined. The visual acuity measuring device according to claim 7,
The drive unit is a visual acuity measurement device that moves the display unit in a direction to approach the subject when the subject is a nearsighted person. The visual acuity measuring device according to claim 7,
The drive unit is a visual acuity measurement device that moves the display unit in a direction away from the subject when the subject is a hyperopic. The visual acuity measuring device according to any one of claims 1 to 9,
Has a vision recovery training mode to train the imaging adjustment function of the eye,
During the vision recovery training mode,
The display unit displays an image for training,
The drive unit continuously reciprocates the display unit,
The display control unit projects the training image on the retina with a certain size according to the set visual acuity value according to a distance between the eye position of the subject and the position of the display unit. A visual acuity measuring device that changes the display size of the training image.

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