A rectangular planar fresnel lens

Abstract

The utility model discloses a kind of rectangular plane fresnel lenses, belong to the technical field of fresnel lens, including the lens main body with rectangular sink, the outside of lens main body is the convex rectangular plane lens, the back of plane lens is equipped with lens grain layer, the lens grain layer is composed of 7 pieces of fresnel grain, and it is symmetrical along the left and right of lens main body's central axis;The left and right sides of the lens grain layer are large-area fresnel grain, which is beneficial to absorb large-angle energy and can expand the detection range. The utility model can be in the limited range of lens, only need to match a sensor, the detection angle can reach 120 degrees, and the detection range is 8 meters away in front;Rectangular plane lens can meet the detection requirement of large angle, and the appearance is beautiful, easy to assemble. The utility model is especially suitable for the application situation of intelligent doorbell.

Description

Technical Field

[0001] This utility model belongs to the field of Fresnel lens technology, and specifically relates to a rectangular planar Fresnel lens. Background Technology

[0002] As is well known, Fresnel lenses are essential components for smart home products such as cameras and webcams to display their functions. Their function is to collect infrared light emitted by the human body and then focus the infrared light onto the sensor surface. In conjunction with smart cameras and webcams, they can detect the infrared light emitted when a person moves, thereby activating and capturing images.

[0003] Currently, the maximum detection angle of existing planar lenses is 100-110 degrees. In order to achieve a larger detection range, this utility model provides a rectangular planar Fresnel lens to meet application requirements and also meet the aesthetic requirements of the design of most smart home products. Utility Model Content

[0004] The purpose of this invention is to provide a rectangular planar Fresnel lens, which aims to solve the technical problem of the small detection range of existing planar Fresnel lenses.

[0005] To address the above problems, this invention provides a rectangular planar Fresnel lens.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows: A rectangular planar Fresnel lens includes a lens body with a rectangular groove, the outer side of the lens body is a protruding rectangular planar lens, and the back of the planar lens is provided with a lens texture layer, the lens texture layer is composed of 7 Fresnel patterns and is symmetrical about the left and right sides along the central axis of the lens body; the left and right sides of the lens texture layer are large areas of Fresnel patterns.

[0007] Preferably, the detection angle of the lens body is 120 degrees and the detection distance is 8 meters.

[0008] Preferably, the lens body is used to be suspended at a height of 1.2 to 1.5 meters.

[0009] Preferably, the center of the 7 Fresnel patterns is the fourth focusing area, and the two sides are symmetrical, with the first focusing area, the second focusing area, and the third focusing area on each side from the outside to the inside; the area of ​​the first focusing area on both sides is larger than the area of ​​the second, third, and fourth focusing areas.

[0010] Furthermore, the second, third, and fourth focusing areas have the same area, and the dimensional tolerance of the Fresnel pattern is ±0.5mm.

[0011] Furthermore, the width of the first focusing area is 10.69±0.5mm and the height is 12.63±0.5mm; the width of the second focusing area is 3.5±0.5mm and the height is 12.63±0.5mm; the width of the third focusing area is 3.5±0.5mm and the height is 12.63±0.5mm; and the width of the fourth focusing area is 3.5±0.5mm and the height is 12.63±0.5mm.

[0012] Furthermore, the thickness of the lens body is 0.5-0.8mm, and the dimensional tolerance of the lens body is ±1mm.

[0013] Furthermore, the edges of the four sides of the lens body are provided with an outwardly folded skirt, and the four sides of the skirt are in the same plane and parallel to the plane lens.

[0014] Furthermore, the sidewall and skirt edge of one long side of the lens body are rounded at both ends, while the sidewall and skirt edge of the other side are right angles.

[0015] The beneficial effects of adopting the above technical solution are as follows: Compared with the prior art, this utility model, by setting a lens texture layer composed of 7 Fresnel patterns on the back of a rectangular flat lens, and adopting a symmetrical design on both sides with large areas of Fresnel patterns on the left and right sides, is conducive to absorbing large-angle energy and can expand the detection range. This utility model can achieve a detection angle of 120 degrees and a detection range of 8 meters in front, requiring only one sensor within the limited range of the lens; the rectangular flat lens can meet the requirements of large-angle detection, while also being aesthetically pleasing and easy to assemble. This utility model is particularly suitable for smart doorbell applications. Attached Figure Description

[0016] The accompanying drawings are provided to further understand the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention and do not constitute a limitation thereof.

[0017] In the attached diagram: Figure 1 An external view of a rectangular planar Fresnel lens provided for an embodiment of this utility model; Figure 2 This is a schematic diagram of the lens texture layer on the back of the lens body in an embodiment of this utility model; Figure 3 for Figure 2 Right view of the main body of the middle lens; The attached figures are labeled as follows: 100-Lens body, 101-Planar lens, 102-Lens texture layer, 103-Skirt; 1-First spotlight zone, 2-Second spotlight zone, 3-Third spotlight zone, 4-Fourth spotlight zone. Detailed Implementation

[0018] To make the technical problem to be solved, the technical solution, and the beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model. In the following detailed description of the present utility model, some specific details are described in detail. However, for the parts not described in detail, those skilled in the art can fully understand the present utility model.

[0019] Furthermore, those skilled in the art should understand that the accompanying drawings are provided only to illustrate the purpose, features, and advantages of this utility model, and are not actually drawn to scale.

[0020] Furthermore, unless the context explicitly requires it, the words "comprising," "including," and similar terms throughout the specification and claims should be interpreted as including rather than exclusive or exhaustive; that is, meaning "including but not limited to."

[0021] like Figures 1-3 As shown in the figure, an embodiment of this utility model provides a rectangular planar Fresnel lens, including a lens body 100 with a rectangular groove. The outer side of the lens body 100 is a protruding rectangular planar lens 101. The back of the planar lens 101 is provided with a lens texture layer 102, which consists of seven Fresnel patterns symmetrically arranged along the central axis of the lens body 100. The left and right sides of the lens texture layer 102 have large areas of Fresnel patterns, which can expand the detection range. A lens with this structure can achieve a detection angle of 120 degrees within the limited range of the lens, and a detection range up to 8 meters in front.

[0022] like Figure 2 The central part of the seven Fresnel patterns is the fourth focusing area 4, and the two sides are symmetrical, with the first focusing area 1, the second focusing area 2, and the third focusing area 3 on each side from the outside to the inside. The area of ​​the first focusing area 1 on both sides is larger than the areas of the second focusing area 2, the third focusing area 3, and the fourth focusing area 4, and the areas of the second focusing area 2, the third focusing area 3, and the fourth focusing area 4 are the same, which is conducive to absorbing large-angle energy.

[0023] In the specific design, the width of the first focusing area 1 is 10.69±0.5mm and the height is 12.63±0.5mm; the width of the second focusing area 2 is 3.5±0.5mm and the height is 12.63±0.5mm; the width of the third focusing area 3 is 3.5±0.5mm and the height is 12.63±0.5mm; and the width of the fourth focusing area 4 is 3.5±0.5mm and the height is 12.63±0.5mm. The dimensional tolerance of the Fresnel pattern is controlled at ±0.5mm, the thickness of the lens body 100 is 0.5-0.8mm, and the dimensional tolerance of the lens body 100 is ±1mm.

[0024] The lens body 100 has an outwardly folded skirt 103 around its four sides. The skirt 103 is in the same plane and parallel to the planar lens 101. In specific manufacturing, the flatness of the skirt is controlled to 0.2mm. The length of the planar lens portion is 40.07±0.1mm, the width is 13.83±0.08mm, and the thickness is 0.6±0.1mm. The total length of the lens body with the skirt is 42.82±0.15mm, the total width is 16.58±0.1mm, and the thickness is 3.5±0.05mm, while the skirt thickness is 0.6±0.05mm. The surrounding skirt can match the appearance of the product. To match the mounting holes of the product, the sidewall and skirt edges of one long side of the lens body 101 are rounded, while the sidewall and skirt edges of the other side are right angles. During installation, the lens body 100 is suspended at a height of 1.2 to 1.5 meters.

[0025] During the manufacturing process, the lens body with the skirt is made using a one-piece molding process. The outer surface of the lens is finished with a glossy black coating, and the Fresnel pattern is not visible on the outside; it is only visible on the back. After installation, it is assembled with the customer's product for a more aesthetically pleasing appearance.

[0026] The working principle of this invention is as follows: A lens texture layer is formed by 7 Fresnel patterns symmetrically arranged on both sides. The texture area of ​​the first focusing area on both sides is relatively large, which is beneficial for absorbing energy at large angles. This lens, paired with a sensor, can detect angles up to 120 degrees and a detection range of 8 meters in front within the limited range of the lens. When installed at a height of 1.2 to 1.5 meters, it can expand the detection field of view. Simultaneously, the black glossy surface matches the appearance of the customer's product, and it is easily assembled by using a skirt-like mounting. This invention is particularly suitable for applications in smart doorbells.

[0027] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of the claims of this utility model.

Claims

1. A rectangular planar Fresnel lens, characterized in that: The lens body includes a rectangular groove, the outer side of which is a protruding rectangular flat lens. The back of the flat lens is provided with a lens texture layer, which is composed of 7 Fresnel patterns and is symmetrical about the left and right sides along the central axis of the lens body. The left and right sides of the lens texture layer are large areas of Fresnel patterns.

2. A rectangular planar Fresnel lens according to claim 1, characterized in that: The detection angle of the lens body is 120 degrees, and the detection distance is 8 meters.

3. A rectangular planar Fresnel lens according to claim 2, characterized in that: The lens body is designed to be suspended at a height of 1.2 to 1.5 meters.

4. A rectangular planar Fresnel lens according to claim 3, characterized in that: The center of the seven Fresnel patterns is the fourth focusing area. The two sides are symmetrical, and each side is divided into the first, second, and third focusing areas from the outside to the inside. The area of ​​the first focusing area on both sides is larger than the areas of the second, third, and fourth focusing areas.

5. A rectangular planar Fresnel lens according to claim 4, characterized in that: The second, third, and fourth focusing areas have the same area, and the dimensional tolerance of the Fresnel pattern is ±0.5mm.

6. A rectangular planar Fresnel lens according to claim 5, characterized in that: The width of the first focusing area is 10.69±0.5mm and the height is 12.63±0.5mm; the width of the second focusing area is 3.5±0.5mm and the height is 12.63±0.5mm; the width of the third focusing area is 3.5±0.5mm and the height is 12.63±0.5mm; and the width of the fourth focusing area is 3.5±0.5mm and the height is 12.63±0.5mm.

7. A rectangular planar Fresnel lens according to claim 6, characterized in that: The thickness of the lens body is 0.5-0.8mm, and the dimensional tolerance of the lens body is ±1mm.

8. A rectangular planar Fresnel lens according to any one of claims 1-7, characterized in that: The edges of the four sides of the lens body are provided with an outwardly folded skirt, and the four sides of the skirt are in the same plane and parallel to the plane lens.

9. A rectangular planar Fresnel lens according to claim 8, characterized in that: The sidewall and skirt of one long side of the lens body are rounded at both ends, while the sidewall and skirt of the other side are right angles.

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