JPH08206064A - Visual acuity examination device - Google Patents

Abstract

PURPOSE: To provide a visual acuity examination device by which optometry can be performed in an adequate condition regardless of a physical condition of a subject, by providing with a beam splitter or the like which is arranged on an optial path and moves to guide index beam to a tested eye with different heights. CONSTITUTION: A power supply switch is switched 'on' after position a subject on a specified front position, and an angle changing motor 13 and a horizontally rotary motor 21 are normally rotated, respectively, as well as lighting an illumination lamp of an index test device body 2. A beam splitter 11 is rotated and an initial position is detected when the beam splitter 11 is made contact with a micro switch 17. Thereafter, the angle changing motor 13 is reversed and moved until the index optial path comes to the index optial path B which fitts to the height of a standard tested eye. Similarly, the horizontally rotaty motor 21 is reversed after the body 2 is made rotated horizontally to decide the initial position. Further, the visual acuity examination is performed by operating a remote controller 40 after the rear part of the remote controller 40 is positioned in a specified relation to the tested eye so as to make the index beam precisely incident into the tested eye.

Description

Detailed Description of the Invention

[0001]

[0001]

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a space-saving type visual acuity test device for inspecting the visual acuity of an eye to be inspected.

[0003]

[0002]

[0004]

2. Description of the Related Art A predetermined eye examination distance is required for a visual acuity test, but an eye examination distance is optically secured by using a mirror etc. without arranging the eye to be inspected and a visual target (visual acuity chart) linearly. A space-saving type visual acuity test device has been proposed.

This type of device has a relatively small mirror that reflects the luminous flux of the target toward the subject's eye, and the subject looks at the target in the housing through the mirror.

[0006]

[0003]

[0007]

However, since the conventional apparatus presents the target to the eye to be examined by utilizing the reflection of the mirror as described above, the tolerance to the change in the position of the eye to be examined is small and the sitting height is high. However, the low one had the drawback that it forced an unreasonable posture.

[0008]

The present invention has been devised in view of the above-mentioned drawbacks of the prior art, and an object of the present invention is to provide a visual acuity that enables an examinee to perform an optometry in an appropriate state regardless of physical conditions. To provide an inspection device.

Another object of the present invention is to provide a visual acuity test apparatus which has a structure as simple as possible, facilitates maintenance of the apparatus, and can accurately measure visual acuity.

[0010]

[0005]

[0011]

In order to achieve the above object, the present invention is characterized by having the following constitution. (1) In a space-saving type visual acuity testing device in which an optical system for presenting a visual target for inspecting the visual acuity of an eye to be inspected is arranged in a predetermined housing, a large number of visual acuity testing eyes are provided on a substantially vertical surface in the housing. A target switching unit that has a target and can dispose the target for visual acuity test at a predetermined presentation position, a reflecting member that reflects the target light flux from the target switching unit upward in the housing, and the reflecting member. A concave mirror for reflecting the light flux reflected by the downward direction and securing a predetermined inspection distance, and for guiding the target light flux to the eye to be inspected which is arranged in the optical path between the concave mirror and the reflecting member and has a different height. It is characterized in that it has a beam splitter which is movable to the left and a beam outlet for outputting the beam reflected by the beam splitter to the outside of the housing.

[0012]

(2) The optotype switching means of (1) includes a rotating disk plate having a plurality of optotypes for visual acuity test on the same circumference, and the presentation position of the optotype for visual acuity test is optotype switching. It is characterized in that the eye to be inspected is sometimes set so as to recognize the movement of the target in the vertical direction.

[0013]

(3) The optotype switching means of (1) is provided with a rotary disc plate having a plurality of visual targets for visual acuity test on the same circumference, and the disc surface of the rotary disc plate is in the line-of-sight direction of the eye to be examined. And the presenting position of the visual acuity test index is above the rotating disk plate.

[0014]

[0008]

[0015]

Embodiment 1 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic perspective view of the apparatus according to the present embodiment as viewed from the right side, FIG. 2 is a schematic perspective view of the apparatus as viewed from the front, and FIG.
Is a schematic perspective view when viewed from above.

The configuration of the apparatus of this embodiment will be described separately for the optotype inspection apparatus main body and the remote control section.

[0017]

(Optical system main body) 1 is an eye to be inspected,
Reference numeral 2 denotes a main body of the optotype inspecting apparatus that presents an optotype to the eye 1 to be inspected.

A window 3 is arranged on a side of the optotype inspection apparatus main body 2 facing the eye 1 to be inspected, and the eye 1 to be inspected sees the optotype through the window 3. The inside of the optotype inspecting apparatus main body 2 is painted black to make it difficult for the eye 1 to be inspected to see the internal structure.

[0019]

Reference numeral 4 is a disc-shaped optotype disc plate made of glass or the like, and an optotype 5 is drawn on the same circumference of the optotype disc plate 4 by chromium vapor deposition. Target disc plate 4
Is rotated by a target disc motor 6 to switch and arrange the target 5 to be presented to the subject. Reference numeral 7 denotes a mask plate for masking a part of the optotype 5, which is rotated by a mask plate motor 8 to apply a desired mask.

[0020]

An illumination lamp 9 illuminates the visual target. 1
Reference numeral 0 is a mirror, 11 is a beam splitter, and 12 is a concave mirror. The target 5 is arranged at the focal length of the concave mirror 12 (the optical distance between the target and the eye to be examined may be a finite distance such as 5 m). Target 5 illuminated by illumination lamp 9
The light flux is reflected upward by the mirror 10, passes through the beam splitter 11 along the optical path A, and then is reflected by the concave mirror 12. The target luminous flux reflected by the concave mirror 12 is reflected by the beam splitter 11 and enters the subject's eye 1 through the target optical path B.

[0021]

The beam splitter 11 moves up and down in the reflection direction of the target luminous flux, so that its inclination angle changes. Reference numeral 13 denotes an angle changing motor for changing the inclination angle of the beam splitter 11, which is fixed inside the optotype inspecting apparatus body 2. A support shaft 14 that supports the beam splitter 11 is fixed to the rotation shaft of the angle changing motor 13. The beam splitter 11 is supported by a support shaft 15 coaxial with the support shaft 14, and the support shaft 15 has a bearing 16.
It is rotatably held by the optotype inspection apparatus main body 2 via. As the rotation angle of the angle changing motor 13 changes the rotation angle of the beam splitter 11, the target optical path B reflected by the beam splitter 11 is the target optical path B according to the positions of the eye 1'and the eye 1 ''. 'And the target optical path B''
Can be changed like. Reference numerals 1'and 1 '' respectively show states when the height of the eye 1 to be inspected changes due to a difference in sitting height or the like.

[0022]

Reference numeral 17 denotes a microswitch for detecting the initial position of the tilt angle of the beam splitter 11.

[0023]

The upper part of the optotype inspecting apparatus main body 2 is a fixed cradle
It is held rotatably in the horizontal direction with respect to 0. Reference numeral 21 denotes a horizontal rotation motor, and a wheel 22 is attached to the rotation shaft of the motor 21. Reference numeral 23 is a worm wheel that meshes with the wheel 22. The worm wheel 23 is fixed to a shaft 24 coaxial with the optical path A, and the shaft 24 is fixed to the fixed pedestal 2
It is planted at 0. When the wheel 22 is rotated by the drive of the motor 21, the upper portion of the visual target inspecting device main body 2 is horizontally rotated with respect to the fixed pedestal 20 via the thrust bearing 25, and the target luminous flux reflected by the beam splitter 11 is left and right. Move to.

[0024]

The optotype inspecting apparatus main body 2 has a detection mechanism for detecting the position of the eye to be inspected. Reference numeral 30 denotes a condensing lens, which condenses infrared light emitted from a light emitting section of a remote controller, which will be described later, on the two-dimensional position detecting element 31. Two-dimensional position detection element 31
As the above, a semiconductor position detecting element used in an autofocus camera or the like is preferable. The vertical and horizontal positions of the remote control light emitting unit are detected by the image position of the light emitting unit of the remote control formed on the two-dimensional position detecting element 31.

[0025]

The detection mechanism includes a pair (condensing lens 30,
30 ', two-dimensional position detection elements 31, 31') are arranged so that position detection signals can be sent from either the left or right side of the subject.

[0026]

Further, the optotype inspecting apparatus main body 2 is provided with a transmitting / receiving section for exchanging signals for optotype switching with the remote controller. Reference numeral 32 is a light receiving section for receiving a signal from the remote controller, and 33 is a light emitting section for sending an optical signal for confirmation to the remote controller.

[0027]

The (remote control unit) 40 is a remote control for switching the visual target, and FIG. 4 is a view showing its appearance. Reference numeral 41 is an optotype changeover switch group for selecting an optotype having a required visual acuity value, and 42 is a position transmission switch for transmitting an optical signal for position detection. 43 and 44 drive the angle changing motor 13 or the horizontal rotation motor 21 by manual operation,
It is an optical path changing switch for changing the optical path of the target. Reference numeral 45 is a display unit for displaying the optotypes presented on the optotype inspection apparatus main body 2.

[0028]

At the rear of the remote controller 40, there are provided a light emitting portion 46 which emits a pulse signal by infrared light and a light receiving portion 47 which receives an optical signal from the light emitting portion 33.

[0029]

The operation of the apparatus having the above configuration is
Description will be made with reference to the electric system block diagram of FIG.

The subject is positioned at a predetermined position on the front and a power switch (not shown) is turned on. The control unit 50 of the optotype inspecting apparatus main body 2 receives the signal, turns on the illumination lamp 9 via the driver 51, and rotates the angle changing motor 13 and the horizontal rotation motor 21 forward through the driver 52 and the driver 53, respectively. Let The beam splitter 11 rotates clockwise in FIG. 1 by the forward rotation of the angle changing motor 13. When the upper rear surface of the beam splitter 11 hits the micro switch 17, the micro switch 17 is energized and the initial position is detected. After detecting the initial position, the control unit 50 reverses the angle changing motor 13 and moves it until the target optical path becomes the target optical path B that matches the standard eye height. Similarly, the horizontal rotation motor 21
After the main body 2 is horizontally rotated by the normal rotation of 1, the initial position is determined by a signal of a micro switch (not shown), and the horizontal rotation motor 21 is reversed by a predetermined amount.

[0031]

Next, the examiner operates the remote controller 4 as shown in FIG.
The rear part of 0 is placed in a predetermined relationship with the eye to be examined. That is, the rear portion of the remote controller 40 is adjusted to the height position of the eye 1 to be inspected, and is placed at a position outside the sight line of the eye to be inspected by a certain amount (it may be placed on the line of sight, the allowable amount in the left-right direction is Since it is relatively large, a rough position of the subject's ear may be used.), And the position transmission switch 42 is pressed. The signal from the position transmission switch 42 is input to the control unit, and the control unit controls the operation of the light emitting unit 46 and converts it into an infrared pulse signal.
The infrared pulse signal is received by the light receiving unit 32 of the main body 2, subjected to predetermined processing by the signal processing circuit 54, and input to the control unit 50. The control unit 50 sets the position signal of the eye to be inspected to the receiving state, and reads the position of the eye to be inspected from the signal of the two-dimensional position detecting element 31. The position signal of the two-dimensional position detecting element 31 is taken into the control unit 50 via the signal processing circuit 55, and position data in the vertical and horizontal directions is obtained. Based on this position data, the control unit 50 rotates the motor 13 and the motor 21 by a corresponding amount via the driver 52 and the driver 53. The position of the beam splitter 11 with respect to the subject's eye is moved by the rotation of the motor 13 and the motor 21, and the target luminous flux is directed toward the subject's eye 1.

[0032]

After the target luminous flux is accurately incident on the eye 1 to be inspected in this way, the examiner operates the remote controller 40 to perform a visual acuity test. When the switch of the optotype changeover switch group 41 is pressed to select the presentation optotype, the remote control light emitting unit 4
The signal emitted from 6 is received by the light receiving unit 32. The control unit 50 drives the motor 6 via the driver 56 to set the visual target 5 corresponding to the received switch signal in the optical path. The moving direction of the optotype is the left-right direction (in the drawing of FIG. 1) at the position of the optotype disc plate 4, but it is reflected by the beam splitter 11 and recognized by the eye to be inspected so as to be switched up and down. .

The control unit 50 also transmits the target information corresponding to the presented target from the light emitting unit 33 to the remote controller 40 through the signal processing circuit 57. By displaying the optotype information on the display unit 45 based on the signal received by the light receiving unit 47 of the remote controller 40, a discrepancy between the display content and the presented optotype can be prevented.

[0034]

In the present embodiment, the light emitting portion 46 and the light receiving portion 47 arranged on the remote controller 40 are provided at the rear portion of the remote controller 40. This is provided when the examiner faces the examinee (obliquely front). This is because it is convenient when it is located, and as shown in FIG. 6, a light emitting unit 46 ′ and a light receiving unit 47 ′ having the same functions as the light emitting unit 46 and the light receiving unit 47 are further provided in the front, and the remote control is directed to either You may also like.

[0035]

Further, in this embodiment, the light source for detecting the position of the eye to be inspected is provided in the remote controller, and the eye position to be inspected is detected by bringing the remote controller close to the eye to be inspected. However, as shown in FIG. It may be attached to a temporary frame into which eyeglasses and inspection lenses are inserted.

[0036]

Although the tilt angle of the beam splitter 11 is changed as a means for adjusting the target optical path to the height position of the eye to be inspected, the visual acuity test apparatus main body 2 is placed on a pedestal that can be moved up and down. May be driven by the height position detection signal.

[0037]

Further, in order to move the optotype optical path up and down and to the left and right, in the embodiment, a mechanism for changing the inclination angle of the beam splitter 11 and a mechanism for horizontally rotating the upper part of the optotype inspection apparatus main body 2 are combined. , Beam splitter 11
May be rotated about two axes.

[0038]

[0027]

[0039]

Second Embodiment In the first embodiment, the two-dimensional position detecting element is used to detect the position of the eye to be inspected, but in the second embodiment, the four-division light receiving element is arranged near the concave mirror-12 for detection.

FIG. 8 is a schematic perspective view of the apparatus of Example 2 as viewed from the right side. The same members as those in the first embodiment are designated by the same reference numerals.

Reference numeral 60 is a condenser lens, and 61 is a light receiving element divided into four as shown in FIG.

[0042]

The light beam for position detection emitted from the light emitting portion 45 of the remote controller is reflected by the beam splitter 11 and goes upward, and the condenser lens 60 forms an image of the light emitting portion on the four-division light receiving element 61. By comparing the amounts of light between the four divided light receiving elements, the motor 13 and the motor 21 are driven to change the target optical path. That is, when changing the angle of the beam splitter 11, the control unit 50 controls the upper and lower light receiving elements (61a, 6a).
1b and 61c, 61d (for convenience, the influence of the position due to reflection is not taken into consideration), the light amount difference between them is compared, and the motor 13 is rotated so that the image of the light emitting unit moves to the vertical center of the light receiving element 61. To do.

[0043]

Similarly, in the left-right direction, the control unit 50 compares the light amount differences between the left and right light receiving elements (61a, 61c and 61b, 61d), and the image of the light emitting unit moves to the center of the light receiving element 61 in the left and right direction. Thus, the motor 21 is driven.

In this way, the target optical path moves toward the subject's eye.

[0045]

[0030]

[0046]

Third Embodiment FIG. 10 is a schematic configuration diagram of an apparatus according to the third embodiment. The third embodiment is an embodiment in which the optotype inspecting apparatus main body 2 and the subjective inspection apparatus of the first embodiment are combined, and the beam splitter 11 is detected by detecting the height position of the subjective inspection apparatus.
Change the reflection target optical path.

[0047]

Reference numeral 70 denotes a subjective eye examination device placed in front of the eye 1 to be examined, and the subjective eye examination device 70 is suspended and held by an arm 71. The arm 71 is supported by a shaft 72, and the shaft 72 is held by a pole 73 fixed to an optometry table (not shown) so as to be vertically movable in the axial direction.

[0048]

A horizontally extending connecting plate 74 is attached to the lower end of the shaft 72, and the leading end of the connecting plate 74 is connected to the timing belt 75. Pulleys 76 and 77 are arranged at the upper and lower ends of the timing belt 75, and the rotary shaft of a rotary potentiometer 78 is fixed to the center of the pulley 76.

[0049]

When the subjective eye examination device 70 is moved up and down together with the shaft 72 to adjust the height of the examination window 70a of the subjective eye examination device 70 to the eye 1 to be inspected, the vertical movement position of the shaft 72 is the connecting plate 7.
4, via the timing belt 75, the potentiometer 7
8 is sent to the control circuit 79 as a resistance value change signal.
The control circuit 79 rotates the motor 13 by a predetermined amount corresponding to the signal and drives the beam splitter 11 to direct the target optical path B toward the eye 1 to be inspected.

In the embodiment, the position adjustment in the left-right direction is not performed, but it can be performed in the same manner as in the first embodiment.

[0051]

[0034]

[0052]

[Fourth Embodiment] A fourth embodiment is an embodiment of an apparatus having an optotype presenting mechanism having a different structure from the first embodiment, and FIG.
FIG. 3 is a schematic right side perspective view for explaining the optotype presenting unit of the device. In the figure, the same or equivalent parts or members as those of the first embodiment are designated by the same reference numerals, and the duplicated description will be omitted.

[0053]

An optical system having the following configuration is arranged inside the optotype inspecting apparatus main body 2 '.

The optotype drawn on the optotype disc plate 4 is illuminated by turning on the illumination lamp 9, and the flux of the optotype is passed through the first mirror 80 and the second mirror 81 to the beam splitter 1.
After passing through 1, it is guided to the concave mirror 12 '. The target light flux whose inspection optical axis is extended to almost infinity by the reflection of the concave mirror 12 ′ is reflected upward by the beam splitter 11 and directed toward the eye 1 by the third mirror 82. In the optical path from the beam splitter 11 to the third mirror 82, a transparent glass 83 that blocks a space from the outside is arranged.

[0055]

The third mirror 82 is rotatable about a shaft 84, a cam barrel 85 is arranged at the lower end of the third mirror 82, and the rotation shaft of the motor 13 'is eccentric to the outer periphery of the cam barrel 85. It is fixed. Further, a shaft 86 is fixedly provided on the outer periphery of the cam barrel 85, and the rotation shaft of the motor 13 'is shown in FIG.
By rotating in the counterclockwise direction 1, the microswitch 17 'is pressed, and the initial position of the third mirror 82 is detected.

Since the optotype presenting section of the fourth embodiment is constructed as described above, a signal from the position detecting means for detecting the height of the eye 1 to be inspected as in the first, second or third embodiment is used. Thus, the motor 13 'is drive-controlled, and the angle of the third mirror 82 is changed according to the height position of the eye 1 to be inspected.

Various modifications can be made to the above-described embodiment, and the scope of the present invention is not limited to the embodiment.

[0058]

[0037]

[0059]

As described above, according to the present invention,
The optometry can be performed in an appropriate state regardless of the physical condition of the subject.

Further, since the optotype disc plate for switching the optotypes is vertically arranged in the apparatus, it is possible to reduce dust and the like adhering to the optotype surface, which facilitates maintenance of the apparatus.

Further, when the target is switched by the rotation of the target disc plate, it seems to the subject that the target flows in the vertical direction and the target is switched, so that it is possible to prevent a sense of discomfort in the case of the horizontal switching.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of the device of Example 1 as viewed from the right side.

FIG. 2 is a schematic perspective view of the apparatus of Example 1 as viewed from the front.

FIG. 3 is a schematic perspective view of the apparatus of Example 1 as viewed from above.

FIG. 4 is a diagram showing an appearance of a remote control for switching the optotypes.

FIG. 5 is a block diagram of an electric system of the device of the first embodiment.

FIG. 6 is a diagram showing a modification of the remote control for switching the optotypes.

FIG. 7 is a diagram showing an example in which a light source for detecting the position of an eye to be inspected is attached to glasses.

FIG. 8 is a schematic perspective view of the device of Example 2 as viewed from the right side surface.

FIG. 9 is a diagram showing a four-division light receiving element.

FIG. 10 is a schematic configuration diagram of an apparatus of Example 3.

FIG. 11 is a schematic right side perspective view for explaining the optotype presenting section of the device of the fourth embodiment.

[Explanation of Codes] 2 Visual Inspection Device Main Body 3 Window 4 Visual Disc Disk 6 Visual Disc Disk Motor 10 Mirror 11 Beam Splitter 12 Concave Mirror 13 Angle Change Motor

Claims (3)

[Claims] 1. A space-saving visual acuity test apparatus in which an optical system for presenting an optotype for inspecting visual acuity of an eye to be inspected is arranged in a predetermined housing, and a large number of visual acuity tests are performed on a substantially vertical surface in the housing. An optotype switching means that has an optotype for visual acuity test and can dispose the optotype for visual acuity test at a predetermined presentation position; a reflecting member that reflects the optotype luminous flux from the optotype switching means upward in the housing; A concave mirror for reflecting the light flux reflected by the reflecting member downward and securing a predetermined inspection distance, and a target light flux for the eye to be inspected having different heights arranged in the optical path between the concave mirror and the reflecting member. A visual acuity test apparatus comprising: a beam splitter movable for guiding; and a light beam outlet for outputting a light beam reflected by the beam splitter to the outside of the housing. 2. The optotype switching means according to claim 1, further comprising a rotating disk plate having a plurality of optotypes for visual acuity inspection on the same circumference, and the presenting position of the optotypes for visual acuity inspection is at the time of optotype switching. A visual acuity test apparatus characterized in that an eye to be inspected is set so as to recognize movement of an optotype in a vertical direction. 3. The optotype switching means according to claim 1, comprising a rotary disc plate having a plurality of visual targets for visual acuity test on the same circumference, and the disc surface of the rotary disc plate is set to be the direction of the line of sight of the eye to be examined. A visual acuity test device, wherein the visual acuity test targets are arranged in parallel with each other, and the presented position of the visual acuity test target is above the rotating disk plate.