KR100479257B1 - Eye testing device having chart-changing apparatus - Google Patents

Abstract

An optometrist having a chart converting apparatus having a plurality of charts and providing an appropriate chart according to the state of an eyepiece to be visualized, not only induces the eye of the eye, but also minimizes an eye measurement error is disclosed. The optometry includes a lamp for emitting visible light; A chart support positioned at the front of the lamp and having at least two charts mounted thereon; And driving means for positioning the chart in a path of visible light emitted from the lamp to move the chart support so that the image formed on the chart is projected to the eye of the examinee.

Description

Optometry with chart conversion device {Eye testing device having chart-changing apparatus}

The present invention relates to an optometrist having a chart conversion device, and more particularly, includes a plurality of charts, and provides an appropriate chart according to the state of the subject to be visually measured, thereby inducing the interest of the subject. The present invention relates to an optometry having a chart conversion device capable of minimizing measurement errors.

The refractive power of the eye should be measured when the eye is in a distant state in order to obtain an accurate measurement value. However, the measurement of the refractive power of the eye using an eye refractometer may interfere with the adjustment of the subject and cause measurement errors. Here, the control refers to a reflexive action of forming a clear image on the retina by changing the thickness of the lens, that is, the refractive power, as the eye moves the ciliary muscles of the eye. This is commonly referred to as "mechanical myopia," and this myopia is severe when the subject is a young person. In order to eliminate the refractive error measurement error caused by such adjustment, the display of about +1 to 2 D is corrected and the focal point of the eye is blurred, thereby making the eye to be in a far-away state, called fogging.

Hereinafter, a process of measuring the refractive power using the cloud method will be described in more detail with reference to FIG. 1. FIG. 1 is an example of a conventional refractometer for measuring refractive power, and as shown in FIG. 1, a conventional refractive power meter fixes a line of sight of an eye, and a chart image generator for performing a fogging process. 20, a measurement light source 10 for scanning the refractive power measurement light, a measurement light detector 12 for detecting the measurement light reflected from the retina 3 of the eye to be examined 1, and a test procedure for performing the operation process And a photodetector 40 for detecting the chart image reflected from the retina 3 in the eye 1. Referring to the operation of the optometry, the visible light emitted from the lamp 22 of the chart image generation unit 20 passes through the chart 24 to form an image, the formed image is the first relay lens 25 And a chart image on the retina 3 of the eye to be examined 1 through the reflection mirror 26, the second and third relay lenses 27 and 28, and the first and second beam splitter mirrors 35 and 36. do. The image of the eye by the illumination light (not shown) reflected from the cornea 2 is passed through the first and second beam splitter mirrors 35 and 36, the third relay lens 28, and the fourth relay lens 37. Is incident on the photodetector 40. After observing the image of the eye formed in the photodetector 40 to match the optical axis of the eye and the optometry, the first relay lens 25 is moved to focus on the target (chart 24) of the eye 1. . As described above, in the state in which the eye 1 is in focus, the operation process of moving the position of the first relay lens 25 to make the eye 1 out of focus is performed. Through such a clouding process, the lens of the eye to be examined (1) is relaxed to a state of distant vision (시 方 視). In this state, the refractive power measurement light is emitted from the measurement light source 10, and the emitted measurement light is focused in the fifth relay lens 11 and passes through the center of the hole mirror 19. It enters into the retina 3 of the eye to be examined 1 via the one-beam splitter mirror 35. The measurement light reflected from the retina 3 is reflected by the hole mirror 19 through the first beam splitter mirror 35, separated into six measurement light by the six-hole plate 13, and then the sixth relay lens. It is focused at 14 and is incident on the photodetector 15. Since the advancing direction of the six measurement lights separated from the six-hole plate 13 depends on the refractive power of the eye 1, the position of the six eyes to be measured is determined by using the positions of the six measurement lights formed on the photodetector 15. The refractive power can be calculated.

2 is a view for explaining the mechanical configuration of the chart image generating unit 20 of the conventional refractive power meter, a lamp for projecting visible light in parallel with the eye of the subject 52 on the upper part of the eyepiece 50 ( 22) a relay lens 54 which is fixed to the front surface of the lamp 22 and transmits the chart 24 on which the predetermined image is formed and the image formed on the chart 24 to the eye of the subject 52. ) Is mounted, and an adjustment handle 51 for varying the position of the relay lens 54 is mounted on the side of the optometry 50. An image for guiding the eye of the examinee 52, for example, a landscape, a cartoon, a figure, a figure, or the like is formed in such a chart 24. However, since the conventional optometry 50 includes only one chart 24 on which one image is formed, there is a disadvantage in that it is not possible to cause an interest of the examinees of various age groups. As such, when the chart 24 fails to induce or concentrate the eye of the subject 52, it may cause shaking of the eye, making it difficult to measure refractive power, or cause measurement errors (mechanical myopia). For example, when a cartoon is drawn on the chart 24, there is an effect that can fix the gaze by inducing interest to a young examinee, but does not cause an interest of an adult or an elderly person. In particular, this problem occurs more seriously when the examinee is a distracted child or an elderly person.

It is therefore an object of the present invention to provide an optometry with a chart conversion device capable of providing charts of various images.

Another object of the present invention is to provide an optometrist having a chart converting apparatus capable of inducing interest of an examinee by providing a chart of an image suitable for an examinee of various age groups.

It is still another object of the present invention to provide an optometrist having a chart converting apparatus capable of minimizing or eliminating eye movements of an examinee and minimizing or eliminating refractive error measurement errors such as mechanical myopia.

In order to achieve the above object, the present invention is a lamp for emitting visible light; A chart support positioned at the front of the lamp and having at least two charts mounted thereon; And driving means for positioning the chart in a path of visible light emitted from the lamp to move the chart support so that the image formed on the chart is projected to the eye of the examinee. to provide.

Here, in the chart support, three charts on which different images are formed are mounted at an angle of 120 degrees, and three openings are formed on opposite sides of the three charts, respectively, so that the visible light is reflected on one chart. It is preferable to let the exit through the opening formed in the opposite surface of the chart. In addition, a detection rod is mounted at one end of the chart support, and further includes a photointerrupter for detecting the position of the detection rod, or at least one groove is formed at a predetermined angle on an upper portion of the chart support. It is preferable to further include a stopper including a projection which is caught by the groove as it rotates, so that the position of the chart support can be fixed.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. For convenience of description, the same reference numerals are given to members that perform the same functions as in the prior art.

3 is a partially cutaway side view of an optometrist equipped with a chart conversion apparatus according to an embodiment of the present invention, and FIGS. 4A and 4B are a perspective view and a cross-sectional view of a chart support used in the optometry according to an embodiment of the present invention. As shown in FIG. 3, the chart converting apparatus of the optometrist 50 according to an embodiment of the present invention includes a lamp support 60, a chart support 60 for supporting two or more charts 62a, 62b, and 62c. And driving means 66 for moving the chart support 60.

The lamp 22 emits visible light to project an image formed on the charts 62a, 62b, and 62c to the examinee, and may use various lighting means such as a light emitting diode (LED), which is commonly used. . In addition, an illumination guide 70 for directing visible light emitted from the lamp 22 to the charts 62a, 62b, and 62c may be formed on the front surface of the lamp 22 as necessary. The chart support 60 for supporting the two or more charts 62a, 62b, 62c moves the chart support 60 to replace each chart 62a, 62b, 62c mounted on the chart support 60 with the lamp. It is for positioning in the path | route of the visible light radiate | emitted from (22). One preferred example of such a chart support 60 is shown in FIGS. 4A and 4B. As shown in FIGS. 4A and 4B, the chart support 60 has a cylindrical shape, and three charts 62a, 62b, and 62c having different images formed at an angle of 120 degrees are mounted on the side of the cylinder. In addition, three openings 63a, 63b, and 63c are formed at opposite sides of the three charts 62a, 62b, and 62c, respectively, and an image formed by displaying visible light on one chart 62a is displayed in the chart 62a. It exits through the opening 63a formed in the opposite surface of the. Since the charts 62a, 62b, and 62c have different images such as cartoons, landscapes, and figures, the inspector can rotate the chart support 60 by 120 degrees to project the most suitable image for the subject. Such a chart support 60 may not only have a cylindrical shape, but also may have a variety of structures in which the image formed by the visible light is reflected on the charts 62a, 62b, and 62c, such as hexagonal columns and triangular pillars, without being disturbed by other charts. have.

A step motor 66 may be used as a driving means for rotating the chart support 60, and the rotational force of the step motor 66 is driven by the drive shaft 64 mounted at the lower end of the chart support 60. It may be delivered to the support 60. The rotational position of the chart support 60 determines the initial position by detecting the position of the detection rod 65 mounted at one end of the chart support 60 using the photointerrupter 68, or the charts 62a and 62b. Alternatively, 62c may be adjusted so that the lamp 22, the relay lens 54, and the subject 52 are physically or optically aligned with each other. Control of the rotational movement of the chart support 60 adjusts the step angle of the step motor 66, or mounts the three detection rods 65 on the chart support 60 at a 120 degree angle , respectively, and the chart support 60 May be performed by detecting the operation of the photo interrupt 68 generated every time the device rotates 120 degrees, or may be performed using a motor having a position recognition function. In addition, after the chart support 60 is rotated by a predetermined angle, the holding torque of the step motor 66 is used, or the position of the rotation shaft of the step motor 66 is fixed, and the chart 62a, The positions of 62b and 62c may not be changed. The types of charts 62a, 62b, and 62c currently being projected are displayed on the CRT or LCD screen (not shown) attached to the optometrist 50 in the form of pictures or letters. The type of the charts 62a, 62b, and 62c can be converted by controlling the step motor 66 and / or the photo interrupt 68 using the control keys.

5A and 5B illustrate a front view and a plan view of a chart conversion apparatus according to another embodiment of the present invention, respectively. In the embodiment shown in FIGS. 5A and 5B, the chart support 60 is used to fix the position of the chart support 60. The grooves 72a, 72b and 72c are formed at an angle of 120 degrees on the upper portion of the 60 ( see FIG. 5B) , and the protrusions 76 of the stopper 74 mounted at predetermined positions of the optometrist are formed on the chart support 60. The position of the chart support 60 can be stably fixed by engaging the grooves 72a, 72b, 72c formed in the upper portion. At this time, by configuring the stopper 74 with a material having elasticity, the stopper 74 serves as a spring can minimize the problem caused by mechanical wear.

Next, the operation of the optometry equipped with the chart conversion device according to the present invention will be described with reference to FIG. 3. First, the eye of the examinee 52 seated in front of the optometrist 50 is matched with the optometrist 50 using the adjustment handle 51 attached to the optometrist 50. Next, the charts 62a, 62b, and 62c to be projected to the examinee are selected by referring to the pictures or letters displayed on the CRT or LCD screen (not shown) attached to the optometrist 50, and steps are performed using separate control keys. The motor 66 and the photo interrupt 68 are controlled to switch the types of the charts 62a, 62b, and 62c. When the types of the charts 62a, 62b, and 62c are determined as described above, the lamp 22 mounted behind the charts 62a, 62b, and 62c is activated to project the charts 62a, 62b, and 62c image to the examinee. do. At this time, the images of the charts 62a, 62b, and 62c projected on the examinee are magnified at a predetermined magnification through an optical system (not shown) such as the relay lens 54. Thus, after fixing the eye of the subject 52, the visual refractive power is measured according to a conventional method. The chart converting apparatus according to the present invention can be applied to various optometry such as not only the eye refractive index measuring instrument, but also various optometry using the chart, for example, an eye fundus measuring apparatus, a corneal curvature measuring instrument, and a corneal surface shape measuring instrument.

As described above, the optometrist equipped with the chart conversion apparatus according to the present invention can not only induce the curiosity and interest of the examinee, especially a child, by projecting charts of various images to the examinee, but also the eyes of the examinee. By minimizing the movement of the lens, refractive error measurement errors such as mechanical myopia can be minimized.

1 is a view for explaining the structure of a conventional optometry for measuring the refractive power.

2 is a view for explaining the mechanical configuration of the chart image generation unit of a conventional refractive power meter;

3 is a partial cutaway side view of an optometrist with a chart conversion device in accordance with one embodiment of the present invention.

Figures 4a and 4b are respectively a perspective view and a cross-sectional view of the chart support used in the optometry according to an embodiment of the present invention.

5A and 5B are a front view and a plan view, respectively, of a chart conversion device used in an optometrist according to another embodiment of the present invention.

Claims (5)

A lamp for emitting visible light; A chart support positioned at the front of the lamp and having at least two charts mounted thereon; And In the optometry having a chart converting device including a driving means for positioning the chart in the path of visible light emitted from the lamp to move the chart support so that the image formed on the chart is projected to the eye of the examinee. , Three charts with different images are mounted on the chart support at an angle of 120 degrees, and three openings are formed on opposite sides of the three charts, so that an image formed by displaying visible light on one chart is displayed on the chart support. An optometrist having a chart conversion device, which is configured to exit through an opening formed on an opposite side of the. delete 2. An optometry as claimed in claim 1, wherein said drive means is a step motor. 2. An optometry according to claim 1, wherein a detection rod is mounted at one end of the chart support, and further comprising a photointerrupter for detecting the position of the detection rod. The method of claim 1, wherein at least one groove is formed at a predetermined angle on an upper portion of the chart support, and further includes a stopper including a protrusion that is caught by the groove as the chart support rotates. An optometrist having a chart converter, which can be fixed.