Pocket visual chart inspection equipment
By designing a pocket-type vision meter inspection equipment and integrating the lens barrel, vision screen and light source, the problem of inconvenience of vision meter inspection equipment and environmental interference is solved, convenient and accurate vision detection and home self-examination are achieved, and the popularity of vision examination is improved.
Patent Information
- Application Number
- CN202422261980.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-14
- Publication Date
- 2025-08-22
- Estimated Expiration
- 2034-09-14
AI Technical Summary
The existing vision meter examination equipment is restricted by space and is not portable. The environment is very disturbed during the examination of children, and there is false reporting of vision, so vision cannot be accurately measured.
A pocket-type vision meter inspection device is designed, including a lens barrel, vision screen, light source, variable aperture and eyepiece, shorten the observation distance through the lens, integrate light source and lighting control, and set up a rotating handle to prevent memory deviation, which is suitable for home self-examination.
It realizes convenient and accurate vision detection, reduces environmental interference, and avoids false reporting of vision. It is suitable for families to conduct self-inspection at any time and improves the popularity of vision examinations.
Smart Images
Figure CN223248177U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of vision testing equipment, in particular to a pocket vision chart testing device. Background Art
[0002] The visual acuity chart is designed based on the principle of visual angle. Visual angle is the angle formed by light rays from two external points passing through a node inside the eye (that is, the angle formed when two external objects intersect the eye). Under normal circumstances, the minimum visual angle formed by the smallest distance between two points that the human eye can distinguish is called the minimum visual angle, or 1 point. The standard for normal vision is 5 points (5.0), which is equivalent to a decimal visual acuity of 1.0.
[0003] Current eye charts, such as light boxes and projector screens, have the following problems when used: 1. They are mostly placed 5m, 2.5m or more away from the person being examined, which is limited by space; 2. The eye chart needs to be hung or projected at a certain distance during the examination. Even a 25cm close-up eye chart needs to be placed on the table, which is very inconvenient and unsightly; 3. Children's vision examinations are often conducted in hospitals and schools. Due to the influence of the environment, the lighting brightness cannot be effectively controlled, and shadows or air flow cause interference, resulting in uneven illumination of the eye chart; 4. There is a phenomenon of memorizing eye charts among children, often because children do not want others to know that their eyesight is worse than others, thus developing a strong desire to falsely report, which is not conducive to accurately measuring vision and correcting it.
[0004] Therefore, we propose a pocket eye chart examination device to solve the problems raised above. Utility Model Content
[0005] The purpose of the utility model is to provide a pocket vision chart examination device to solve the problems in the current market raised by the above background technology.
[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a pocket eye chart examination device, comprising:
[0007] A lens barrel, wherein an observation window is provided at the front end of the lens barrel;
[0008] Vision screen, installed in the lens barrel;
[0009] A light source is disposed in the lens barrel and located behind the vision screen;
[0010] A variable aperture is provided in the lens barrel and is located in front of the vision screen. The variable aperture is connected to an aperture indicator dial for adjusting the visual range, and the aperture indicator dial is rotatably sleeved on the rear end of the lens barrel;
[0011] The eyepiece is installed inside the lens barrel near the observation window.
[0012] Preferably, the distance from the eyepiece to the vision screen is 125 mm, and the equivalent distance, i.e., the visual distance of the human eye, is 250 mm, i.e., the object distance u=125, the image distance v=-250, and the magnification β=2.
[0013] Preferably, the bottom surface of the lens barrel is provided with a visual acuity value scale in the circumferential direction, and the visual range of the vision screen can be changed by rotating the aperture indicator dial to the corresponding visual acuity value scale.
[0014] Preferably, an eye chart indicator is provided at the center of the bottom surface of the lens barrel, and the eye chart indicator is used in conjunction with the synchronous eye chart by checking the direction of the eye chart indicator.
[0015] Preferably, a rotating handle is rotatably mounted on the outer side of the lens barrel.
[0016] Preferably, the lens barrel is provided with a switch for controlling the opening and closing of the light source.
[0017] Preferably, the inner wall of the lens barrel is provided with a black matte coating.
[0018] Compared with the prior art, the beneficial effects of the present invention are:
[0019] (1) The present invention uses a lens between the vision screen and the observer to shorten the observation distance, proportionally reduce or enlarge the distance between two points on the vision chart, and achieve the required viewing angle for the two points to reach the fundus. The lighting, vision screen, optical path, and observation port are integrated into one space to form a pocket-sized handheld device. The self-examination can be completed by holding it close to the eyes. The device is compact and beautiful, can be taken out for use at any time, and is easy to store.
[0020] (2) The present invention uses background light to illuminate the eye chart in a black, sealed lens barrel, effectively controlling the light intensity and maintaining consistent illumination during each examination.
[0021] (3) The present invention is provided with a rotating handle. When in use, after randomly turning and stopping, the opening direction of the "E" in the internal vision screen is random and cannot be predicted by the viewer, so that the memory of the orientation is invalid, thereby enabling accurate measurement of vision and avoiding false reporting.
[0022] (4) The present invention makes the vision test device pocket-sized and can be brought into the home, so that children can check their vision at any time and inform their parents of the results. This reduces the situation in which children in a group environment compete with each other in visual ability and develop a mentality of lying, which results in the inability to obtain true vision.
[0023] The above summary is for the purpose of description only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments and features described above, further aspects, embodiments and features of the present invention will be readily apparent by reference to the accompanying drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Figure 1 This is a schematic diagram of the cross-sectional structure of a pocket vision chart testing device of the present invention;
[0025] Figure 2 This is a schematic diagram of the bottom structure of a pocket vision chart testing device of the present invention;
[0026] Figure 3 This is a schematic diagram of the vision screen observed in the eyepiece when the aperture indicator dial of the utility model is rotated to 0.6;
[0027] Figure 4 This is the intention of the utility model to express synchronous vision;
[0028] Figure 5 This is a schematic diagram of the vision screen of the utility model;
[0029] Figure 6 The letter "E" is replaced by the letter "C" in this utility model.
[0030] In the figure: 1. Eyepiece barrel; 2. Vision screen; 3. Variable aperture; 4. Eyepiece; 5. Aperture indicator dial; 6. Light source; 7. Vision value; 8. Vision chart indicator; 9. Rotating handle; 10. Switch; 11. Synchronized vision chart. DETAILED DESCRIPTION
[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.
[0032] See also Figures 1-6 , a pocket eye chart examination device, comprising:
[0033] The lens barrel 1 has an observation window 101 at its front end for close observation with a single eye. A rotating handle 9 is mounted on the outside of the lens barrel 1. The handle 9 is located on the outside of the lens barrel 1 and can be rotated along the outside of the lens barrel 1. The inner wall of the lens barrel 1 is coated with a black matte coating to reduce the impact of stray light on the observer.
[0034] The vision screen 2 is installed in the lens barrel 1; the vision screen 2 is printed with a vision chart, such as Figure 5 The diameter of the vision screen 2 is 38 mm and is suitable for a magnification of 2.
[0035] Light source 6 is disposed within lens barrel 1 and behind vision screen 2. Light source 6 can be an LED lamp and is equipped with a power supply. This power supply can be designed as a replaceable power supply. A removable opening is provided at the bottom of lens barrel 1 to allow for battery replacement. It can use button cells or AA batteries. Replaceable power supplies are conventional technology and will not be described in detail here. A switch 10 is provided on lens barrel 1 to control the on / off of light source 6.
[0036] The variable aperture 3 is arranged in the lens barrel 1 and is located in front of the vision screen 2. The variable aperture 3 is connected to an aperture indicator dial 5 for adjusting the visual range, and the aperture indicator dial 5 is rotatably sleeved on the rear end of the lens barrel 1; the aperture indicator dial 5 is limited to the outside of the lens barrel 1 and can be rotated along the circumference of the outside of the lens barrel 1. The bottom of the aperture indicator dial 5 has a fan-shaped surface structure, such as Figure 2 shown.
[0037] The bottom surface of the lens barrel 1 is provided with a visual acuity scale 7. Each time the aperture indicator dial 5 is turned, it corresponds to a visual acuity scale 7. Turning the aperture indicator dial 5 to the corresponding visual acuity scale 7 can change the visual range of the visual screen 2. Figure 2 The position shown, that is, when the indicator is “0.6”, the vision screen 2 observed in the eyepiece 4 is as follows Figure 3 As shown, the aperture edge indicates the 0.6 visual edge.
[0038] An eye chart indicator mark 8 is provided at the center of the bottom surface of the lens barrel 1 , and the eye chart indicator mark 8 is used in conjunction with the synchronous eye chart 11 by checking the direction of the eye chart indicator mark 8 .
[0039] The eyepiece 4 is mounted in the lens barrel 1 near the observation window 101. The distance from the eyepiece 4 to the vision screen 2 is 125 mm, and the equivalent distance, i.e., the visual distance of the human eye, is 250 mm, i.e., the object distance u = 125, the image distance v = -250, and the magnification β = v / u = 2.
[0040] Eyepiece diopter: D = 1 / u + 1 / v = 1000 / 125 - 1000 / 250 = 4D.
[0041] Assume that the equivalent side length of 5.0 visual acuity "E" under 4D lens is x. It is known that the side length of 1' visual acuity chart "E" at a clear vision distance of 250mm is 0.36mm, so v / u = 0.36 / x, that is, x = 0.36 / β.
[0042] By analogy, the equivalent near vision chart data is as follows (citing the GB / T 11533-2011 standard logarithmic vision chart)
[0043]
[0044] The working principle of this embodiment: When using the pocket eye chart examination device, first, turn the aperture indicator dial 5 to any vision value scale 7, turn on the light source 6 through the switch 10, hold the rotating handle 9, observe with one eye through the eyepiece 4 of the observation window 101, and start measuring vision after rotating the lens barrel 1 to any angle. The parent holds the synchronized eye chart 11 and uses it according to the direction of the eye chart indicator 8 on the bottom of the lens barrel 1. If the currently displayed minimum sight mark can be seen clearly, continue measuring vision by turning the aperture indicator dial 5 to the next vision value scale 7 until the final vision is measured.
[0045] This new device breaks through the traditional eye chart examination method, but the basic principle is the same: using the angle of view to distinguish vision. This new device breaks through the traditional eye chart or light box or projector eye chart examination method, using lenses to achieve an equivalent angle of view between two points, thereby greatly shortening the observation distance, making the device pocketable and more convenient, making vision screening more popular, and thus deepening the implementation of high-quality prevention and control measures for myopia in children and adolescents.
[0046] The utility model can arbitrarily design the distance between the eyepiece 4 and the vision screen 2 within the clear vision distance of 250 mm, and use lenses with different magnifications to design vision charts with different viewing angles, thus realizing a pocket vision chart examination device. The utility model also proposes for the first time the concept of using the magnification β to convert the side length of the sight mark in the vision chart.
[0047] The distance from the eyepiece to the eye chart is u, and the imaging position is v. In the near vision test, v is defined as the visual distance of 250mm. At this distance, the human eye is most relaxed. There is a geometric optical formula for magnification:
[0048] β=v / u=image size / object size=sight mark side length / designed vision screen side length, so we can use the side length of the sight mark on the standard vision chart at the clear vision distance to convert, and get:
[0049] Design the side length of vision screen 2 = side length of sight mark / β.
[0050] In addition, the letter "E" in the present invention can be replaced by the letter "C", such as Figure 6 shown.
[0051] In this utility model, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, indirect connection through an intermediate medium, internal communication between two components, or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on specific circumstances.
[0052] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.
[0053] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.
[0054] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are illustrative and cannot be understood as limitations on the present invention. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present invention.
Claims
1. A pocket eye chart examination device, characterized in that: include: A lens barrel (1), wherein the front end of the lens barrel (1) is provided with an observation window (101); A vision screen (2) is installed in the lens barrel (1); A light source (6) is disposed in the lens barrel (1) and located behind the vision screen (2); A variable iris (3) is arranged in the lens barrel (1) and located in front of the vision screen (2); the variable iris (3) is connected to an iris indicator dial (5) for adjusting the visual range, and the iris indicator dial (5) is rotatably sleeved on the rear end of the lens barrel (1); The eyepiece (4) is installed in the lens barrel (1) near the observation window (101).
2. A pocket vision chart testing device according to claim 1, characterized in that: The bottom surface of the lens barrel (1) is provided with a visual acuity scale (7) on its circumference. The visual range of the visual screen (2) can be changed by rotating the aperture indicator dial (5) to a corresponding visual acuity scale (7).
3. The pocket vision chart testing device according to claim 1, characterized in that: A vision chart indicator mark (8) is provided at the center of the bottom surface of the lens barrel (1), and the vision chart indicator mark (8) is used in conjunction with the synchronous vision chart (11) by checking the direction of the vision chart indicator mark (8).
4. The pocket eye chart examination device according to claim 1, characterized in that: A rotating handle (9) is rotatably mounted on the outer side of the lens barrel (1).
5. The pocket vision chart testing device according to claim 1, characterized in that: The lens barrel (1) is provided with a switch (10) for controlling the opening and closing of the light source (6).
6. The pocket vision chart testing device according to claim 1, characterized in that: The inner wall of the lens barrel (1) is provided with a black matte coating.