Visual chart

Abstract

According to the technical scheme, the visual chart is characterized in that the visual chart comprises a chart body base material and a vision detection graph arranged on the chart body base material, and the chart body base material is provided with a detection graph area corresponding to the vision detection graph and a blank graph area located on the periphery of the vision detection graph; a reflective coating is arranged on the detection pattern area and / or the blank pattern area, and when the reflective coating is arranged on the detection pattern area, a non-reflective color filling layer is arranged on the blank pattern area; when a reflective coating is arranged on the blank image area, a non-reflective color filling layer is arranged on the detection image area; when the detection pattern area and the blank pattern area are both provided with the reflective coatings, the detection pattern area is provided with a non-reflective color filling layer. In this way, when the visual chart is used in a dark environment, a user only needs to hold the light source by hand to illuminate the visual chart, vision detection can be conveniently conducted by the user through the light reflecting effect of the light reflecting coating, the use scene is not limited by a power source any more, and the use flexibility and the application range of the visual chart are greatly improved.

Description

Technical Field

[0001] This utility model relates to the field of vision testing tools, and more specifically, to a vision chart. Background Technology

[0002] A vision chart is a chart used to measure visual acuity; it contains visual acuity test graphics.

[0003] Currently, Chinese patent application number 201220318612.1 discloses a vision chart, which includes: a rectangular vision chart box with a transparent glass front surface; rotating rollers with handles at the top and bottom of the box; a strip vision chart with at least two sets of complete vision symbols printed on its surface wound on the rotating rollers; the paper with the vision symbols is located behind the transparent glass; and a plate-shaped LED light-emitting screen is installed behind the strip vision chart. Although this vision chart improves the light source from ordinary fluorescent tubes to a plate-shaped LED light-emitting screen, making the brightness of the entire vision chart uniform and soft, which is conducive to the examinee's recognition of vision symbols, the existing vision charts combined with light boxes are too bulky and inconvenient to carry, and can only be used in environments with power supply, limiting their applicable scenarios. Therefore, many manufacturers and experts have carried out development and research, but so far no ideal product has been launched. Utility Model Content

[0004] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a vision chart to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a vision chart, comprising a chart substrate and a vision testing pattern disposed on the chart substrate, wherein the chart substrate is provided with a testing pattern area corresponding to the vision testing pattern and a blank pattern area located around the vision testing pattern, and the testing pattern area and / or the blank pattern area are provided with a reflective coating.

[0006] When a reflective coating is provided on the detection area, a non-reflective color filling layer is provided on the blank area;

[0007] When a reflective coating is provided on the blank area, a non-reflective color filling layer is provided on the detection area;

[0008] When both the detection area and the blank area are provided with reflective coatings, the detection area is provided with a non-reflective color filling layer.

[0009] The present invention is further configured such that the substrate of the surface is made of soft paper, cloth or film.

[0010] In summary, this utility model has the following beneficial effects: when used in a dark environment, the person testing vision only needs to hold a light source and shine it on the eye chart. The reflective coating makes it convenient for the person testing vision to perform vision tests. The usage scenarios are no longer limited by the power supply, which greatly improves the flexibility and applicability of the eye chart. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of a vision chart;

[0012] Figure 2 This is a schematic diagram illustrating the technical principle of reflective coatings.

[0013] Reference numerals: 1. Substrate; 11. Detection area; 12. Blank area; 2. Visual acuity test pattern; 3. Reflective coating; 31. Glass microspheres; 32. Adhesive layer; 33. Reflective layer. Detailed Implementation

[0014] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention, wherein the same components are represented by the same reference numerals. It should be noted that the terms "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to the directions in the accompanying drawings, and the terms "bottom surface" and "top surface", "inner" and "outer" refer to the directions toward or away from the geometric center of a specific component, respectively.

[0015] Reference Figure 1-2 As shown, a vision chart includes a chart substrate and a vision testing pattern disposed on the chart substrate. The chart substrate has a test pattern area corresponding to the vision testing pattern and a blank pattern area located around the vision testing pattern. The test pattern area is arranged to overlap with the vision testing pattern. A reflective coating is disposed on the test pattern area and / or the blank pattern area. The reflective coating is a known technology and can be made using existing reflective paint. When light shines on the reflective coating, the reflective coating can concentrate most of the light and reflect it back to the light source within a very small angle range, forming retroreflection (also known as "retroreflection"), thereby producing an excellent reflective effect.

[0016] The technical principle of this reflective coating is illustrated by glass microspheres as an example. Figure 2 As shown, when a beam of light shines on the front surface of the microspheres at any angle within a certain range, due to the high refraction of the glass microspheres, the light converges on the reflective layer of the glass microspheres. The reflective layer reflects the light back parallel to the direction of the light source, causing the light to return to the light source, thus forming retroreflection. When many glass microspheres reflect at the same time, the bright scene in front will appear, achieving the reflective effect.

[0017] When the refractive index of the glass microspheres is close to 1.9, the incident light rays can be well focused on the back surface of the glass microspheres, resulting in the best retroreflection effect. When the refractive index is less than or greater than 1.9, the incident light rays are focused on the outside and inside of the glass microspheres, respectively, and the retroreflection effect will be reduced. In practical applications, due to objective conditions, the refractive index of glass microspheres is usually between 1.9 and 2.1, while their diameter is usually less than 0.8 mm. If a reflective layer is added behind the glass microspheres, the retroreflection effect will be even better.

[0018] The production process of glass microspheres is as follows: the raw materials are first melted into molten glass at a very high temperature. The molten glass is then passed through a special nozzle to form many mist-like droplets. These droplets automatically form regular spherical shapes under the action of surface tension. After cooling and further processing, very useful glass microspheres are obtained.

[0019] The specific configuration of the reflective coating is as follows: when a reflective coating is applied to the detection area, a non-reflective filler layer is applied to the blank area; when a reflective coating is applied to the blank area, a non-reflective filler layer is applied to the detection area; when both the detection and blank areas have reflective coatings, a non-reflective filler layer is applied to the detection area. It should be noted that this filler layer is for highlighting the vision test pattern; therefore, the filler layer can be the natural color of the substrate or a color that differs from the vision test pattern.

[0020] In this way, when used in a darker environment, the person being tested only needs to hold a light source and shine it on the eye chart. The reflective coating makes it easy for the person being tested to perform vision tests. The usage scenarios are no longer limited by the power supply, which greatly improves the flexibility and applicability of the eye chart.

[0021] Furthermore, for ease of portability, the base material of the eye chart can be made into a plate shape, which greatly reduces the volume compared to existing eye charts combined with a light box. In addition, the base material of the eye chart can be made of soft paper, cloth or film, so that the eye chart can be folded up, further reducing the volume of the eye chart when stored, making it easier to carry when going out for testing, and greatly improving the flexibility and applicability of the eye chart.

[0022] The above are merely preferred embodiments of this utility model. The protection scope of this utility model is not limited to the above embodiments. All technical solutions falling within the scope of this utility model's concept are within its protection scope. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of this utility model should also be considered within its protection scope.

Claims

1. A vision chart, comprising a chart substrate and a vision testing pattern disposed on the chart substrate, wherein the chart substrate has a testing pattern area corresponding to the vision testing pattern and a blank pattern area located around the vision testing pattern, characterized in that: A reflective coating is provided on the detection area and / or blank area. When a reflective coating is provided on the detection area, a non-reflective color filling layer is provided on the blank area; When a reflective coating is provided on the blank area, a non-reflective color filling layer is provided on the detection area; When both the detection area and the blank area are provided with reflective coatings, the detection area is provided with a non-reflective color filling layer.

2. A visual acuity chart according to claim 1, characterized in that: The substrate of the surface is made of soft paper, cloth or film.

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