Light guide plate, side light type backlight module and display device
By setting a triangular pyramidal optical microstructure on the light-emitting surface of the light guide plate, the problem of uneven brightness caused by point light sources in the light guide plate is solved, resulting in better light emission performance and expanded visible area.
Patent Information
- Application Number
- CN202520030052.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-07
- Publication Date
- 2025-12-16
- Estimated Expiration
- 2035-01-07
AI Technical Summary
When using point light sources, light guide plates are prone to uneven brightness and hot spots, especially in large-size products, which can lead to insufficient light energy and brightness.
A triangular pyramid-shaped optical microstructure is set on the light-emitting surface of the light guide plate. The incident light is converted into outgoing light emitted in different directions by the side facade, forming a linear light spot to improve the hot spot phenomenon.
It effectively improves the light output performance of the light guide plate, avoids uneven brightness, enhances light output performance, meets market demands, and realizes the practical application of the product.
Smart Images
Figure CN223679391U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of optoelectronic display technology, and in particular to a light guide plate, a side-lit backlight module, and a display device. Background Technology
[0002] A light guide plate is an essential component in optoelectronic display devices such as backlight modules and LCD screens. The conventional structure of a light guide plate includes an incident surface for receiving light emitted from a light source, a reflective surface and an emitting surface arranged opposite each other and adjacent to the incident surface, and optical dots disposed on the reflective surface. The working principle of the light guide plate is as follows: light emitted from the light source enters the light guide plate through the incident surface, is then guided by the light within the light guide plate, and homogenized by the optical dots, becoming planar light that exits through the emitting surface.
[0003] When light guide plates are used in optoelectronic display devices (such as edge-lit backlight modules) and point light sources (such as LED chips) are used to provide light entering the light guide plate, the following problem easily occurs due to the characteristics of point light sources: uneven light emission will form in the area adjacent to the light-incident surface of the light guide plate, which is known in the industry as the hotspot phenomenon. The hotspot phenomenon has a significant impact on the light emission performance of the product, especially for large-size products, where insufficient light emission brightness may occur due to weak light energy in some areas.
[0004] In view of the above, this utility model is hereby proposed. Summary of the Invention
[0005] To overcome the above-mentioned defects, this utility model provides a light guide plate, a side-lit backlight module, and a display device. The light guide plate is not only simple, novel, and reasonable in structure, but also has excellent light output performance, avoiding uneven light output. It also enables products such as side-lit backlight modules to have advantages such as excellent light output performance, large viewing area, and no point light source seen when viewed at an angle, thus well meeting market demand.
[0006] The technical solution adopted by this utility model to solve its technical problem is: a light guide plate, including a light guide plate body made of light-transmitting material. The light guide plate body is provided with a light-incident surface opposite to the light source, and a reflective surface and a light-emitting surface arranged back-to-back and respectively adjacent to the light-incident surface. On the light-emitting surface and in the area adjacent to the light-incident surface, there are a plurality of optical microstructures in the shape of triangular pyramids. The optical microstructures are provided with a bottom surface connected to the light-emitting surface and three side surfaces. One of the side surfaces faces the light source, and the remaining two side surfaces can convert the incident light incident into light emitted in two different directions and form a linear light spot, so as to improve the hot spot phenomenon on the light-emitting surface and in the area adjacent to the light-incident surface.
[0007] As a further improvement of the utility model, the optical microstructure is a right triangular pyramid shape, and correspondingly, the bottom surface is an equilateral triangle, and the side vertical surface is an isosceles triangle.
[0008] As a further improvement of the utility model, the side length of the bottom surface is 0.01-0.1 mm; and the top angle of the side vertical surface is 100-140 degrees.
[0009] As a further improvement of the utility model, the optical microstructure is provided with an R angle away from the vertex of the light emitting surface.
[0010] As a further improvement of the utility model, the area formed by extending the side of the light emitting surface adjacent to the light entering surface away from the light entering surface by a certain distance is defined as an optimization area, and the optical microstructures are arranged on the optimization area.
[0011] As a further improvement of the utility model, the light guide plate body is further provided with two auxiliary surfaces which are also oppositely arranged and adjacent to the light entering surface respectively;
[0012] The optimization area is a rectangle, and the two sides of the optimization area in the length direction are adjacent to the two auxiliary surfaces respectively, and the width of the optimization area is 0.5-2 mm;
[0013] The optical microstructures are arranged in rows on the optimization area, and the bottom surfaces of the optical microstructures in the same row are sequentially connected into one body.
[0014] The utility model also provides a side light type backlight module which comprises the light guide plate, the upper frame, the lower frame and the plurality of LED lamp beads.
[0015] As a further improvement of the utility model, the vertical distance between the light emitting surface of the LED lamp bead and the inner side wall of the upper frame adjacent thereto is 0.5-2 mm.
[0016] As a further improvement of the utility model, the light emitting surface of the light guide plate body is defined as being located above the reflecting surface;
[0017] The diffusion film, the prism film and the polaroid are sequentially and upwardly arranged in the accommodation space above the light emitting surface, and the reflecting sheet is arranged in the accommodation space below the reflecting surface.
[0018] This utility model also provides a display device, including the side-lit backlight module as described in this utility model.
[0019] The beneficial effects of this utility model are as follows: 1) By improving the structure of the light guide plate, this utility model provides several triangular pyramid-shaped optical microstructures on the light-emitting surface of the light guide plate and in the area adjacent to the light-incident surface. These optical microstructures achieve a bright line light emission state, effectively improving the hot spot phenomenon on the light-emitting surface and in the area adjacent to the light-incident surface, thus giving the light guide plate better light emission performance and avoiding uneven light emission. 2) The light guide plate provided by this utility model enables products such as side-lit backlight modules to have advantages such as excellent light emission performance, a large visible area, and no point light source visible when viewed from an angle, thus well meeting market demands. 3) The structure of the light guide plate of this utility model is simple, novel, and reasonable. It is easy to process and manufacture, and has low manufacturing costs, which is conducive to product processing and production. Attached Figure Description
[0020] Figure 1 This is a three-dimensional structural diagram of the light guide plate described in Embodiment 1 of this utility model;
[0021] Figure 2 for Figure 1 An enlarged structural diagram of part A shown in the image;
[0022] Figure 3 for Figure 1 A top view of the light guide plate shown in the diagram;
[0023] Figure 4 for Figure 1 A schematic diagram of the light guide plate shown from below;
[0024] Figure 5 for Figure 1 A side view of the light guide plate shown in the diagram;
[0025] Figure 6 for Figure 5 An enlarged structural diagram of section B shown in the figure;
[0026] Figure 7 for Figure 1 The diagram shows the working principle of the light guide plate shown.
[0027] Figure 8 This is a cross-sectional structural diagram of the side-lit backlight module shown in Embodiment 2 of this utility model.
[0028] Referring to the accompanying drawings, the following explanations are provided:
[0029] 1, light guide plate; 10, light guide plate body; 100, light-incident surface; 101, reflecting surface; 102, light-emitting surface; 1020, optimization area; 103, auxiliary surface; 11, optical microstructure; 110, bottom surface; 111, side surface; 2, upper frame; 3, lower frame; 4, LED lamp bead; 5, diffusion film; 6, prism film; 7, polarizer; 8, reflecting sheet. DETAILED DESCRIPTION
[0030] The preferred embodiment of the present application is described in detail below with reference to the drawings.
[0031] Example 1
[0032] The light guide plate provided in this example 1 can effectively improve the hot spot phenomenon caused by the limitation of the point light source characteristics in the prior art, significantly improve the light-emitting performance of the light guide plate, avoid the uneven light-emitting phenomenon, and make the user more comfortable when watching and not affected by the alternating bright and dark areas. Therefore, the light guide plate can be widely applied to the edge-lit backlight module and the display device comprising the edge-lit backlight module.
[0033] The specific structure of the light guide plate provided in this example 1 is described in detail below. Please refer to the drawings Figure 1 to the drawings Figure 7 The light guide plate 1 provided in this example 1 comprises a light guide plate body 10 made of a light-transmitting material, which is provided with a light-incident surface 100 opposite to a light source (specifically, an LED point light source), a reflecting surface 101 and a light-emitting surface 102 which are back-to-back and adjacent to the light-incident surface 100, respectively, and two auxiliary surfaces 103 which are also back-to-back and adjacent to the light-incident surface 100, respectively. In particular, this example 1 is also provided with a plurality of optical microstructures 11 in the shape of triangular pyramids on the light-emitting surface 102 and adjacent to the light-incident surface 100, which are provided with a bottom surface 110 connected to the light-emitting surface 102 and three side surfaces 111, one of which is arranged towards the light source, and the remaining two side surfaces 111 can convert the incident light incident into the optical microstructure 11 into emitted light emitted in two different directions and form a linear light spot (specifically, please refer to the drawings Figure 7 ). That is, the directions of the emitted light emitted by the remaining two side surfaces 111 are opposite but can converge into a linear light spot, that is, the light-emitting state of bright lines can be achieved by the action of the optical microstructure 11, thereby effectively improving the hot spot phenomenon at the area of the light-emitting surface 102 and adjacent to the light-incident surface 100, making the light guide plate 1 have better light-emitting performance and avoiding the uneven light-emitting phenomenon.
[0034] Further, in the embodiment, the light guide plate body 10 can be preferably made of PC (polycarbonate), PMMA (polymethyl methacrylate) or COP (cyclo olefin polymer) material, and the light guide plate body 10 can be processed by using an injection molding process, an extrusion molding process or a hot-press molding process. In addition, the optical microstructure 11 can be formed on the light guide plate body 10 by using a laser engraving process, a V-shaped cross grid engraving process or a UV screen printing process, and accordingly, the bottom surface 110 of the optical microstructure 11 is integrally and coplanarly connected with the light emitting surface 102 (achieved based on the laser engraving or V-shaped cross grid engraving process), or the bottom surface 110 of the optical microstructure 11 is fixedly and adhesively connected with the light emitting surface 102 (achieved based on the UV screen printing process).
[0035] It should be noted that the above-mentioned material selection and processing forming process of the light guide plate body 10 and the processing forming process of the optical microstructure 11 are all conventional technical means in the technical field of light guide plate processing, and therefore will not be described in detail here.
[0036] Further, in the embodiment, the optical microstructure 11 is preferably a right triangular pyramid shape (see FIG. 2), so as to improve the collimation and uniformity of the linear light spot formed. Figure 2 It can be understood that the bottom surface 110 is an equilateral triangle, and the three side surfaces 111 are isosceles triangles.
[0037] Further, according to product design requirements, the length L1 of the bottom surface 110 is preferably controlled to be 0.01-0.1 mm, and the top angle β of the side surface 111 is preferably controlled to be 100°-140°. For details, please refer to FIG. 2 and FIG. 3. Figure 5 Figure 6 In addition, an R corner can be provided on the vertex of the optical microstructure 11 away from the light emitting surface 102, so as to improve the mechanical stability of the optical microstructure 11 and reduce stress concentration. The specific value of the R corner can be determined according to product processing requirements, and the embodiment does not have any limitation requirements.
[0038] Further, in the embodiment, the region formed after the side of the light emitting surface 102 adjacent to the light incident surface 100 extends away from the light incident surface 100 by a certain distance is defined as an optimization region 1020, as shown in FIG. 4 and FIG. 5. Accordingly, the optical microstructure 11 is arranged on the optimization region 1020. Figure 7
[0039] Furthermore, according to product design requirements, the optimized area 1020 can preferably be rectangular, and the two sides of the optimized area 1020 along its length direction are respectively adjacent to the two auxiliary surfaces 103. The width of the optimized area 1020 can preferably be designed to be 0.5 to 2 mm.
[0040] Based on the preferred shape of the optimized region 1020, a plurality of optical microstructures 11 can be arranged in a row on the optimized region 1020, and at the same time, the bottom surfaces 110 of a plurality of optical microstructures 11 located in the same row are connected in sequence to form a whole.
[0041] Example 2:
[0042] Please see the appendix Figure 8 As shown, this embodiment 2 provides a side-lit backlight module, which includes a light guide plate 1, an upper frame 2, a lower frame 3, and a plurality of LED beads 4 as provided in embodiment 1 above. The upper frame 2 and the lower frame 3 are fixedly connected. The light guide plate 1 and the plurality of LED beads 4 are respectively disposed within a receiving space enclosed by the upper frame 2 and the lower frame 3. It can be understood that the fixed connection of the upper frame 2 and the lower frame 3 forms a back frame structure containing a receiving space to house and install the light guide plate 1 and the plurality of LED beads 4. Simultaneously, the plurality of LED beads 4 are arranged side-by-side next to the light incident surface 100 of the light guide plate 1. Further explanation: Based on the structure of the light guide plate 1, the plurality of LED beads 4 are arranged side-by-side along the arrangement direction of the two auxiliary surfaces 103.
[0043] Furthermore, based on the structure of the light guide plate 1 and the functions it achieves, this embodiment can design the vertical distance L2 between the light-emitting surface of the LED bead 4 and an inner sidewall of the adjacent upper frame 2 to be 0.5–2 mm (see Appendix). Figure 8 (As shown). Compared to the existing technology that uses a 3-5mm run-up distance between the emitting surface of the point light source and the effective display area to address hotspot phenomena, the run-up distance in the side-lit backlight module described in this embodiment is shortened to 0.5-2mm. This achieves a narrow bezel design, giving the product a larger viewing area; and thanks to the bright line light emission state of the light guide plate 1, it avoids the problem of seeing the point light source from an angle due to the narrow bezel, thus well meeting the usage requirements of products such as vehicle information terminal systems (CID systems).
[0044] Additional explanation: In the side-lit backlight module structure, the LED beads 4 (i.e., point light sources) generally adopt a flat structure with a planar light-emitting surface.
[0045] Further, if the light exit surface 102 of the light guide plate body 10 is located above the reflection surface 101, the embodiment 2 further has, from bottom to top, a diffusion film 5, a prism film 6 and a reflective polarizer 7 stacked in the receiving space above the light exit surface 102, and a reflective film 8 stacked in the receiving space below the reflection surface 101. Figure 8
[0046] As can be seen from the above, the sidelight backlight module provided by the embodiment 2 has the advantages of good light exit performance, large visual area and no point light source in the squinting state, and well meets the market demand.
[0047] Embodiment 3
[0048] The embodiment 3 provides a display device, which comprises a display panel and the sidelight backlight module provided by the above embodiment 2, and the display panel is arranged on the sidelight backlight module. It can be understood that, based on the functional characteristics of the sidelight backlight module, the display device has good light exit performance, a large display panel (i.e. a large visual area), and makes the user more comfortable and has a very good experience when watching.
[0049] In summary, compared with the prior art, the light guide plate of the utility model not only has simple, novel and reasonable structure, good light exit performance and avoids the light exit phenomenon of uneven brightness, but also enables the sidelight backlight module and other products to have good light exit performance, a large visual area and no point light source in the squinting state, and well meets the market demand.
[0050] In the above description, many specific details are described in order to fully understand the utility model. However, the above description is only the preferred embodiment of the utility model, and the utility model can be implemented in many other ways different from the description, and therefore the utility model is not limited by the above disclosed specific implementation. Meanwhile, any person skilled in the art can make many possible changes and modifications to the utility model technical solution or modify it into equivalent embodiments with the above disclosed methods and technical contents without departing from the scope of the utility model technical solution. Any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the utility model, all still belong to the scope of protection of the utility model technical solution.
Claims
1. A light guide plate comprising a light guide plate body (10) made of a light-transmissive material, the light guide plate body (10) being provided with a light-incident surface (100) disposed opposite a light source, and a reflection surface (101) and a light-emitting surface (102) disposed back-to-back and respectively abutting the light-incident surface (100); characterized in that: The light emitting surface (102) is provided with a plurality of optical microstructures (11) in the shape of triangular pyramids, each of which has a base (110) connected to the light emitting surface (102) and three side surfaces (111), one of which is arranged to face the light source, and the other two are capable of converting incident light into outgoing light in two different directions and forming linear light spots, thereby improving the hot spot phenomenon in the area of the light emitting surface (102) adjacent to the light incident surface (100).
2. The light guide plate according to claim 1, characterized by: The optical microstructure (11) is in the shape of a regular triangular pyramid, and the base (110) is an equilateral triangle, and the side surface (111) is an isosceles triangle.
3. The light guide plate according to claim 2, characterized by: The length of the side of the base (110) is 0.01-0.1 mm; and the vertex angle of the side surface (111) is 100-140°.
4. The light guide plate according to claim 2, characterized by: The optical microstructure (11) is provided with an R corner at the vertex away from the light emitting surface (102).
5. The light guide plate according to claim 1, characterized by: The area formed by extending the side of the light emitting surface (102) adjacent to the light incident surface (100) away from the light incident surface (100) by a certain distance is defined as an optimization area (1020), and a plurality of optical microstructures (11) are arranged on the optimization area (1020).
6. The light guide plate according to claim 5, characterized by: The light guide plate body (10) is also provided with two auxiliary surfaces (103) which are also arranged back to back and adjacent to the light incident surface (100). The optimization area (1020) is rectangular, and the two sides of the optimization area (1020) in the length direction are adjacent to the two auxiliary surfaces (103), and the width of the optimization area (1020) is 0.5-2 mm. A plurality of optical microstructures (11) are arranged in rows on the optimization area (1020), and the bases (110) of the optical microstructures (11) in the same row are sequentially connected into one body.
7. An edge-lit backlight module, characterized in that: The light guide plate (1) according to any one of claims 1-6, an upper frame (2), a lower frame (3), and a plurality of LED lamp beads (4) are provided, the upper frame (2) and the lower frame (3) are fixedly connected, the light guide plate (1) and the plurality of LED lamp beads (4) are arranged in a receiving space surrounded by the upper frame (2) and the lower frame (3), and the plurality of LED lamp beads (4) are also arranged side by side beside the light incident surface (100) of the light guide plate (1).
8. The edge-lit backlight module of claim 7, wherein: The vertical distance between the light emitting surface of the LED lamp bead (4) and the inner side wall of the upper frame (2) adjacent thereto is 0.5-2 mm.
9. The edge-lit backlight module of claim 7, wherein: The light emitting surface (102) of the light guide plate body (10) is located above the reflecting surface (101); In the receiving space and above the light emitting surface (102), a diffusion film (5), a prism film (6), and a polarizing sheet (7) are sequentially stacked from bottom to top, and in the receiving space and below the reflecting surface (101), a reflecting sheet (8) is also stacked.
10. A display device, characterized by comprising: The side light type backlight module comprises the side light type backlight module as claimed in claim 7.