A light guide plate and its application in LED backlight modules

Abstract

This invention discloses a light guide plate and its application in an LED backlight module, belonging to the field of optical backlight technology. The light guide plate is an integrated irregularly shaped light-emitting cover with irregularly shaped refractive grooves arranged on its light-incident surface, sequentially arranged along the propagation direction of the incident light. The LED backlight module using this light guide plate includes a back plate, a cover plate, and a light-emitting element. The irregularly shaped light-emitting cover is installed between the back plate and the cover plate, and the light-emitting element is located on the light-incident side of the irregularly shaped light-emitting cover. This invention, through the multi-level structure of the irregularly shaped refractive grooves, performs multi-angle divergence, uniform light distribution, and secondary diffusion and refraction on the point light source of the light-emitting element, converting the point light source into a uniform surface light source. This completely solves the problems of dark spots and dark areas existing in traditional matrix light-emitting backplates, significantly improving the brightness uniformity of the light-emitting surface. Simultaneously, it achieves an integrated and thin design for the backlight module, adapting to various display and lighting backlighting scenarios.

Description

Technical Field

[0001] This invention relates to the field of optical backlighting technology, and more specifically, to a light guide plate and its application in LED backlighting modules. Background Technology

[0002] LED backlight modules are core components of display devices and lighting fixtures. Their core function is to convert LED point light sources into uniform surface light sources, ensuring consistent brightness and visual effect across the light-emitting surface. Currently, most mainstream LED backlight modules use a matrix arrangement of LED chips combined with a conventional planar light guide plate structure. The dotted pattern on the surface of the light guide plate enables light refraction and diffusion.

[0003] However, in practical applications, the combination of traditional matrix light-emitting backplanes and conventional light guide plates has significant drawbacks: Firstly, the blind spots in light coverage between adjacent LED beads can easily form dark spots and dark areas. Especially in large-size backlight modules, it is difficult to ensure the uniformity of the bright surface. It is necessary to significantly increase the density of LED beads, which not only increases production costs and equipment power consumption, but also exacerbates the heat dissipation pressure of the module. Secondly, conventional light guide plates have a simple refractive structure, which can only achieve light refraction at a fixed angle. They cannot perform multi-dimensional and all-angle homogenization of incident light, resulting in a large difference in brightness between the edge and center areas of the light-emitting surface and a poor visual effect. Third, in order to improve the light uniformity effect, traditional solutions require additional layers of optical film materials such as diffusion film, brightness enhancement film, and reflection film, resulting in a large overall thickness of the module, complex structure, and cumbersome assembly process, which cannot adapt to the development trend of thin and lightweight products; Fourth, the dot structure of conventional light guide plates is prone to wear and aging, and the light uniformity effect is greatly reduced after long-term use, limiting the service life.

[0004] Therefore, in order to solve the problems of prominent dark spots, poor uniformity of bright surfaces, complex structure, and difficulty in thinning of traditional LED backlight modules, it is urgent to develop a light guide plate and corresponding LED backlight module with multi-angle light source refraction capability, which can completely eliminate dark spots and is integrated in one piece. Summary of the Invention

[0005] The purpose of this invention is to overcome the defects of traditional matrix light-emitting backplates, such as dark spots and poor uniformity of bright surfaces, and to provide a light guide plate and its application in LED backlight modules. Through the multi-stage irregular refractive groove group of the irregular light-emitting cover, the light source of the light-emitting body is refracted from multiple angles, thereby making the bright surface of the light-emitting backplate more uniform and completely eliminating the problems of dark spots and dark areas.

[0006] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides a light guide plate; The light guide plate is an integrated irregularly shaped light-emitting cover. The light-incident surface of the irregularly shaped light-emitting cover is arranged with several sets of irregularly shaped refraction grooves for refraction of light sources at multiple angles. The irregularly shaped refraction grooves are arranged sequentially along the propagation direction of the incident light, and are used to convert the incident point light source into a uniform surface light source through multi-order refraction, thereby eliminating dark areas and dark spots on the light-emitting surface.

[0007] As a further improvement to this technical solution, the irregularly shaped refraction groove group includes a concave arc refraction groove, a stepped refraction groove, and a convex arc refraction groove arranged sequentially along the propagation direction of the incident light. The concave arc refraction groove is used to perform the first divergence refraction of the incident light, expanding the light coverage range. The stepped refraction groove is used to perform multi-stage uniform refraction of the light after the first divergence, decomposing a single beam of light into multiple beams of refracted light at different angles. The convex arc refraction groove is used to perform secondary convergence and diffusion of the light after multi-stage uniform refraction, realizing the full-angle uniform projection of the light and filling the light blind zone between adjacent light sources.

[0008] As a further improvement to this technical solution, the concave arc refraction groove, the stepped refraction groove, and the convex arc refraction groove are all arranged in a horizontal array at equal intervals along the light-incident surface of the irregular light-emitting cover. Furthermore, the central axes of a single set of concave arc refraction grooves, stepped refraction grooves, and convex arc refraction grooves are on the same straight line and coaxially correspond to the light-emitting center of the corresponding incident light source. This ensures that the incident light from each set of light sources can accurately enter the corresponding irregular refraction groove group, thereby maximizing the utilization and homogenization of light.

[0009] As a further improvement to this technical solution, the stepped refractive groove adopts a stepped groove structure with at least three steps. The inclination angle of the refractive surface of each step increases sequentially along the direction of light propagation. This is used to decompose the incident light into multiple refracted light beams with different propagation angles, covering the dark area between adjacent incident light sources and eliminating the possibility of dark spot generation from the root.

[0010] As a further improvement to this technical solution, the irregularly shaped light-emitting cover is integrally injection molded from optical-grade PMMA or PC material with high light transmittance, and the light transmittance is ≥92%, ensuring the light propagation efficiency; the edge of the irregularly shaped light-emitting cover is provided with assembly grooves for assembly positioning, which can achieve quick assembly with the back plate and cover plate without additional fasteners, simplifying the assembly process.

[0011] As a further improvement to this technical solution, the light-emitting surface of the irregularly shaped light-emitting cover is provided with a microstructure diffusion layer. The microstructure diffusion layer is arranged opposite to the irregularly shaped refractive groove group to perform final homogenization of the refracted light, further eliminating the brightness difference of the light-emitting surface and improving the uniformity of the bright surface.

[0012] Secondly, the present invention provides an LED backlight module; The LED backlight module, which uses the light guide plate described above, also includes a back plate, a cover plate, and at least one set of light emitters. The irregularly shaped light-emitting cover is fixedly installed between the back plate and the cover plate. The light emitter is located on the light-incident side of the irregularly shaped light-emitting cover. The light emitted by the light emitter is refracted at multiple angles by the irregularly shaped refractive groove group and then uniformly projected onto the light-emitting surface of the back plate.

[0013] As a further improvement to this technical solution, a docking component is fixedly installed at the end of the back plate. The docking component includes an electrical connector, a mounting hole, and a control connector. The electrical connector is electrically connected to the light-emitting element, and the control connector is signal-connected to the light-emitting element through the electrical connector to adjust the light-emitting brightness, on / off parameters, etc. of the light-emitting element. The mounting hole is opened at both ends of the docking component for the overall assembly and fixation of the backlight module.

[0014] As a further improvement to this technical solution, the light-emitting body adopts a surface-mount LED bead, and multiple groups of light-emitting bodies are arranged linearly and equally at intervals along the light-incident side of the irregular light-emitting cover. The spacing between two adjacent groups of light-emitting bodies matches the arrangement spacing of the irregular refractive groove group, so as to achieve precise matching of a single LED bead to a single group of irregular refractive grooves and ensure the consistency of the light uniformity effect.

[0015] As a further improvement to this technical solution, the cover plate is an optical-grade light-transmitting cover plate, and the contact surface between the cover plate and the irregularly shaped light-emitting cover is provided with an anti-glare coating, which can effectively reduce light reflection and glare interference and improve the visual effect; the edge of the cover plate and the inner wall of the assembly groove of the edge of the irregularly shaped light-emitting cover are interference fit to achieve sealed assembly, thereby improving the stability of the module structure and its dustproof and waterproof performance.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. The light guide plate of the present invention adopts an integrated irregular light-emitting cover structure. Through the irregular refractive groove group arranged sequentially along the light propagation direction, the point light source of the light source is diffused at multiple angles, uniformly diffused and refracted at multiple levels, and the point light source is converted into a uniform surface light source with full-angle coverage. This completely solves the core problem of dark spots and dark areas between adjacent lamps in traditional matrix light-emitting backplates, and greatly improves the brightness uniformity of the light-emitting surface. The measured brightness uniformity can reach more than 95%.

[0017] 2. This invention uses a multi-stage tilt design of stepped refractive grooves to decompose a single incident light beam into multiple refracted light beams with different propagation angles. This can accurately cover the light blind zone between adjacent light emitters, achieving light emission without dark spots without increasing the density of LED beads. This effectively reduces the production cost and operating power consumption of the module, while also alleviating the heat dissipation pressure of the module and extending its service life.

[0018] 3. The irregularly shaped light-emitting cover of the present invention is an integrated light guide plate structure, which integrates refraction, light uniformity and diffusion functions into one, without the need to add multiple layers of diffusion film, light enhancement film and other optical film materials, which greatly simplifies the structure of the backlight module, realizes the thin and lightweight design of the module, and reduces assembly process and improves production efficiency.

[0019] 4. The irregularly shaped refractive groove assembly and the light guide plate of the present invention are integrally injection molded without additional film material structure, which avoids the problem of light uniformity attenuation caused by film material wear and aging after long-term use. The structure has strong stability and long service life. At the same time, it can be quickly assembled through the assembly groove on the edge, which is suitable for backlighting scenarios of various display devices and lighting fixtures, and has a wide range of applications. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure assembly of the present invention; Figure 2 This is a schematic diagram of the assembly groove in the present invention; Figure 3 This is a schematic diagram of the matrix arrangement of the light-emitting covers in this invention; Figure 4 This is a schematic diagram of the honeycomb-shaped arrangement of the light-emitting cover in this invention; Figure 5 This is a schematic diagram of the docking component in this invention; Figure 6 This is a schematic diagram of the structure of the light-emitting body in this invention; Figure 7 This is a schematic diagram of the structure of various grooves in the light-emitting cover of the present invention; Figure 8 This is a schematic diagram of the process of the present invention.

[0021] The labels in the diagram represent the following: 1. Backplate; 2. Light-emitting cover; 21. Arc-shaped concave refraction groove; 22. Stepped refraction groove; 23. Arc-shaped convex refraction groove; 3. Cover plate; 4. Assembly groove; 5. Connecting component; 51. Electrical connector; 52. Mounting hole; 53. Control connector; 6. Light-emitting body. Detailed Implementation

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Example 1

[0024] Please see Figures 1 to 5 , Figure 7 As shown, this embodiment provides a light guide plate, which is an integrated irregularly shaped light-emitting cover 2. The irregularly shaped light-emitting cover 2 is integrally injection molded from optical-grade PMMA material with a light transmittance of 93%. The light-incident surface of the irregularly shaped light-emitting cover 2 is arranged with several sets of irregularly shaped refraction grooves for multi-angle refraction of light sources. The irregularly shaped refraction grooves are arranged sequentially along the propagation direction of the incident light.

[0025] In this embodiment, the irregular refraction groove group includes an arc concave refraction groove 21, a stepped refraction groove 22, and an arc convex refraction groove 23 arranged sequentially along the propagation direction of the incident light. The arc concave refraction groove 21 is used to perform the first divergence refraction of the incident light, the stepped refraction groove 22 is used to perform multi-stage uniform refraction of the light after the first divergence, and the arc convex refraction groove 23 is used to perform secondary convergence and diffusion of the light after multi-stage uniform refraction.

[0026] Among them, the concave arc refraction groove 21, the stepped refraction groove 22, and the convex arc refraction groove 23 are all arranged in a horizontal array at equal intervals along the light-incident surface of the irregularly shaped light-emitting cover 2. The central axes of a single set of concave arc refraction grooves 21, stepped refraction grooves 22, and convex arc refraction grooves 23 are on the same straight line, coaxially corresponding to the light-emitting center of the corresponding incident light source. The stepped refraction groove 22 adopts a three-stage stepped groove structure. The inclination angle of the refraction surface of each stage of the groove increases sequentially along the light propagation direction, which are 15°, 30°, and 45° respectively, decomposing the incident light into three beams of refracted light with different propagation angles, covering the dark area between adjacent incident light sources.

[0027] The irregularly shaped light-emitting cover 2 has assembly grooves 4 on all four edges for assembly and positioning. The light-emitting surface of the irregularly shaped light-emitting cover 2 is provided with a microstructure diffusion layer, which consists of an array of micron-sized hemispherical protrusions arranged opposite to the irregularly shaped refractive groove group to finally homogenize the refracted light.

[0028] This embodiment also provides an LED backlight module, which uses the light guide plate mentioned above. The LED backlight module also includes a back plate 1, a cover plate 3, and multiple sets of light emitters 6. The irregularly shaped light-emitting cover 2 is fixedly installed between the back plate 1 and the cover plate 3. The back plate 1 is made of aluminum alloy and has a high-reflection coating on the side facing the irregularly shaped light-emitting cover 2 to improve light utilization. The light emitters 6 are surface-mount LED beads. Multiple sets of light emitters 6 are soldered onto a flexible PCB board and arranged linearly and equally spaced along the light-incident side of the irregularly shaped light-emitting cover 2. The spacing between two adjacent sets of light emitters 6 matches the spacing of the irregularly shaped refractive groove group. Each LED bead corresponds to a single set of irregularly shaped refractive groove groups.

[0029] A docking component 5 is fixedly installed at the end of the back plate 1. The docking component 5 includes a power connector 51, mounting holes 52, and a control connector 53. The power connector 51 is a conductive copper sheet that is electrically connected to the flexible PCB board of the light-emitting element 6. The control connector 53 is a standard connector that is connected to the light-emitting element 6 via the power connector 51 to control the light-emitting parameters of the light-emitting element 6. The mounting holes 52 are located at both ends of the docking component 5 for the overall assembly and fixation of the backlight module. The cover plate 3 is made of optical-grade tempered glass. The mating surface of the cover plate 3 and the irregularly shaped light-emitting cover 2 is coated with an anti-glare coating. The edge of the cover plate 3 is press-fitted with the inner wall of the assembly groove 4 on the edge of the irregularly shaped light-emitting cover 2 to achieve a sealed assembly.

[0030] Example 2

[0031] Please see Figure 6 As shown, this embodiment optimizes and improves the arrangement structure of the irregular refractive groove group based on embodiment 1, as follows: In this embodiment, the light-incident surface of the irregular light-emitting cover 2 is provided with two sets of symmetrical light-incident areas. The two sets of light-incident areas are respectively located on the left and right sides of the irregular light-emitting cover 2. Each set of light-incident areas is arranged with an array of irregular refractive groove groups, corresponding to the array of light-emitting bodies 6 on both sides.

[0032] Among them, the stepped refraction groove 22 of the single set of irregular refraction grooves adopts a five-step stepped groove structure. The inclination angle of the refraction surface of each step of the groove increases sequentially along the direction of light propagation, namely 10°, 20°, 30°, 40° and 50°, which further expands the coverage range of light refraction angle. For large-size backlight modules, it can achieve full light emission surface coverage without dead angles and completely eliminate the problem of dark area in the center area of ​​large-size modules.

[0033] Meanwhile, a transition refraction groove is provided between two adjacent sets of irregular refraction grooves. The transition refraction groove is an arc-shaped groove used to supplement and homogenize the refracted light of the adjacent groove sets, further improving the uniformity of the bright surface. The rest of the structure in this embodiment is completely consistent with that in embodiment 1.

[0034] Example 3

[0035] This embodiment provides a method for using the LED backlight module described in Embodiment 1, including the following steps: S1. Module Assembly: Fix the flexible PCB board with the light-emitting element 6 welded on to the light-incident side of the irregular light-emitting cover 2, ensuring that the light-emitting center of each light-emitting element 6 is coaxially aligned with the central axis of the corresponding irregular refractive groove group; assemble the irregular light-emitting cover 2 with the back plate 1 and cover plate 3 through the assembly groove 4 on the edge, and complete the sealed assembly of the module body; fix the docking component 5 to the end of the back plate 1, so that the electrical connector 51 is reliably electrically connected to the flexible PCB board, and complete the overall module assembly.

[0036] S2. Power-on debugging: Connect the control connector 53 to the external drive power supply and control system. After power-on, the light emitted by the light source 6 is incident on the light-incident surface of the irregular light-emitting cover 2. It passes through the first divergence refraction of the arc concave refraction groove 21, the multi-stage uniform light refraction of the stepped refraction groove 22, and the secondary convergence and diffusion of the arc convex refraction groove 23, converting the LED point light source into a uniform surface light source. Finally, after the final homogenization by the microstructure diffusion layer, it is uniformly projected onto the light-emitting surface of the back plate 1, realizing uniform light emission without dark spots or dark areas.

[0037] S3. Parameter adjustment: The brightness and on / off status of the light-emitting body 6 can be adjusted through the control system via the control connector 53 to adapt to the usage requirements of different scenarios and complete the normal use of the module.

[0038] Example 4

[0039] Please see Figure 7 As shown, this embodiment, based on embodiment 1, details the light refraction working logic of the light guide plate and LED backlight module, as follows: Incident stage: The point light source emitted by the light source 6 is incident on the incident surface in a direction parallel to the plane of the irregular light source cover 2. It first enters the corresponding coaxially set arc concave refraction groove 21. The concave arc surface of the arc concave refraction groove 21 will diverge the parallel incident light for the first time, converting the single parallel light into a large-angle divergent light, expanding the initial coverage of the light, and avoiding excessive local brightness caused by concentrated light propagation.

[0040] Multi-stage homogenization stage: After the first divergence, the light propagates to the stepped refraction groove 22. The multi-stage refraction surfaces of the stepped refraction groove 22 with different inclination angles decompose the divergent light into multiple refracted light beams with different propagation angles. The inclination angle of each refraction surface increases, so that the propagation angle of the refracted light gradually expands. Among them, the large-angle refracted light can accurately cover the light blind zone between adjacent light-emitting bodies 6, eliminating the generation of dark spots and dark areas from the root. At the same time, the multi-stage refraction structure enables the light to form total internal reflection propagation inside the irregular light-emitting cover 2, further improving the light utilization rate.

[0041] Secondary homogenization stage: After multi-stage homogenization, the light propagates to the arc-shaped convex refraction groove 23. The convex arc of the arc-shaped convex refraction groove 23 converges and calibrates multiple dispersed refracted light rays to avoid excessively low edge brightness caused by excessive light propagation angle. At the same time, the calibrated light is diffused a second time to form a uniform light field distribution inside the irregular light-emitting cover 2.

[0042] Light emission stage: After being refracted through multiple stages by the irregular refractive groove group, the light propagates to the light emission surface of the irregular light-emitting cover 2. It is then homogenized by the microstructure diffusion layer of the light emission surface, further reducing the brightness difference of the light emission surface. Finally, it is uniformly projected onto the light emission surface of the back plate 1, realizing the output of a surface light source with no dark spots and high uniformity throughout the entire area.

[0043] Comparative Example 1 This comparative example compares the present invention with a conventional matrix LED backlight module (rectangular light-emitting cover backplate arranged in a matrix with equal spacing) in the prior art. Under the same power supply, same external dimensions, and same test environment, the uniformity of light source brightness, number of dark spots and dark areas, and light utilization rate of the light-emitting surface of the backlight are quantitatively detected and compared to verify the core advantage of the present invention in light uniformity.

[0044] The control group of this comparative example uses a conventional matrix LED backlight module, specifically structured as follows: a rectangular planar light-emitting cover (conventional light guide plate) with the same external dimensions as in Embodiment 1 of this invention is used. The light-incident surface of the light-emitting cover only has a traditional circular dot refraction structure, without the irregular refraction groove group described in this invention; the LED light emitters are surface-mount LED beads of the same type and number as in Embodiment 1, arranged in a linear, equally spaced matrix along the light-incident side of the light-emitting cover, with the bead spacing completely consistent with Embodiment 1; the materials, dimensions, and assembly methods of the back plate, cover plate, and mating components of the module are all consistent with those of Embodiment 1. The test group of this comparative example is the LED backlight module described in Embodiment 1 of this invention.

[0045] Test Environment: Ambient temperature and pressure environment, 25℃, 50% relative humidity, dark room environment without external light source interference; Power Supply: Both modules are powered by the same DC regulated power supply, 3.3V, rated input power 10W, tested after 30 minutes of stable power-on; Test Standard: Referring to the brightness uniformity test specification in SJ / T11348-2016 "Measurement Method for Digital Television Flat Panel Displays", the light-emitting surface of the module is equally divided into 9 test areas of 3×3. Five test points are selected in the center and four corners of each area, for a total of 45 test points. A high-precision luminance meter is used to collect the brightness value of each test point, and the brightness uniformity is calculated (brightness uniformity = minimum brightness value / maximum brightness value × 100%). Simultaneously, through visual observation and industrial camera photography, the number of dark spots and dark areas on the glossy surface is counted. The criteria for determining dark spots are: a single point with a brightness lower than 50% of the area's average brightness is considered a valid dark spot; an area consisting of three or more consecutive dark spots is considered a dark area.

[0046] The test results above show that, compared with conventional matrix backlighting in existing technologies, this invention achieves multi-angle refraction homogenization of LED point light sources through the multi-stage irregular refractive groove group of the irregular light-emitting cover 2, improving the brightness uniformity of the light-emitting surface by 25.7%, completely eliminating the dark spots and dark areas between adjacent LEDs in the traditional solution, and reducing the brightness difference between the center and the edge by nearly 90%; at the same time, the light utilization rate is improved by 32.7%, and under the same brightness requirements, the LED arrangement density can be reduced, reducing the operating power consumption by about 30%, greatly alleviating the heat dissipation pressure of the module, and the brightness decay after long-term operation is only 1 / 6 of that of the conventional solution, and the service life is significantly improved.

[0047] Comparative Example 2 This comparative example compares the multi-stage combined irregular refractive groove group of the irregular light-emitting cover 2 of the present invention with a conventional light-emitting cover with a single structure to verify the innovation and technical advantages of the combined structure of the refractive groove group of the present invention. Under the same material, same external size, same light source parameters, and same test environment, the uniform light effect, light coverage ability and structural stability of different refractive structures are compared.

[0048] This comparative example includes three control groups. All control groups are identical to those in Example 1 of this invention in terms of the material, dimensions, light source, and assembly structure of the light-emitting cover. The only difference is in the refractive structure. The specific groupings are as follows: Control group A: The light-emitting cover only has a concave arc refraction groove 21 on the light-incident surface, without a stepped refraction groove 22 and a convex arc refraction groove 23, and the rest of the structure is the same as in Example 1; Control group B: The light-emitting cover only has stepped refractive groove 22 on the light-incident surface, without the arc concave refractive groove 21 and the arc convex refractive groove 23, and the rest of the structure is the same as in Example 1; Control group C: The light-emitting cover has no irregular refractive groove group on the light-incident surface, and only a conventional circular dot refractive structure is set. The rest of the structure is the same as that of Example 1. Test group 1 of this comparative example is the light guide plate described in Embodiment 1 of the present invention, and test group 2 is the light guide plate described in Embodiment 2 of the present invention.

[0049] The test environment and power supply conditions were completely consistent with those of Comparative Example 1. In addition to brightness uniformity and the number of dark spots and dark areas, the test items added were the coverage range of light refraction angle and structural stability test after long-term use. The structural stability test was conducted by working continuously for 2000 hours in a high temperature and high humidity environment (temperature 60℃, relative humidity 90%) and measuring the attenuation rate of the uniform light effect before and after the test. The attenuation rate was calculated as (initial brightness uniformity - brightness uniformity after test) / initial brightness uniformity × 100%.

[0050]

[0051] The test results above show that: Compared to the control group C with a conventional dot structure, the control groups A and B with a single refractive structure can improve the uniformity of light and the light coverage to a certain extent, but they cannot completely eliminate dark spots. The brightness uniformity can only reach a maximum of 84.6%, and they cannot achieve uniform light at all angles and cannot solve the problem of blind spots between adjacent light sources. The multi-stage combined irregular refractive groove group of the present invention, consisting of "circular arc concave refractive groove 21 + stepped refractive groove 22 + circular arc convex refractive groove 23", improves the light refraction angle coverage range to more than ±60° through the three-level refraction logic of "divergence, homogenization, and secondary calibration diffusion". It can completely cover the light blind zone between adjacent light sources, completely eliminate dark spots and dark areas, and improve the brightness uniformity by more than 13% compared with a single structure and more than 26% compared with a conventional dot structure. The irregularly shaped refractive groove assembly of the present invention is integrally injection molded with the light-emitting cover, without any additional film material or dot coating. After long-term operation in a high temperature and high humidity environment, the light uniformity effect decay rate is less than 2%, which is only 1 / 9 of that of conventional dot structures. The structural stability and aging resistance are significantly better than conventional light-emitting covers, greatly extending the service life of the module.

[0052] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples of the present invention and are not intended to limit the present invention. Various changes and modifications can be made to the present invention without departing from the spirit and scope thereof, and all such changes and modifications fall within the scope of the present invention as claimed.

Claims

1. A light guide plate, characterized in that, The light guide plate is an integrated irregular light-emitting cover (2). The light-incident surface of the irregular light-emitting cover (2) is arranged with several sets of irregular refraction grooves for multi-angle refraction of light sources. The irregular refraction grooves are arranged sequentially along the propagation direction of the incident light to convert the incident point light source into a uniform surface light source through multi-order refraction and eliminate the dark area and dark spot of the light-emitting surface.

2. The light guide plate according to claim 1, characterized in that, The irregular refraction groove group includes a concave arc refraction groove (21), a stepped refraction groove (22), and a convex arc refraction groove (23) arranged sequentially along the direction of incident light propagation. The concave arc refraction groove (21) is used to perform the first divergence refraction of the incident light, the stepped refraction groove (22) is used to perform multi-stage uniform light refraction of the light after the first divergence, and the convex arc refraction groove (23) is used to perform secondary convergence and diffusion of the light after multi-stage uniform light, so as to realize the uniform projection of light at all angles.

3. The light guide plate according to claim 2, characterized in that, The circular arc concave refractive groove (21), the stepped refractive groove (22), and the circular arc convex refractive groove (23) are all arranged in a horizontal array at equal intervals along the light-incident surface of the irregular light-emitting cover (2). The central axes of a single set of circular arc concave refractive groove (21), stepped refractive groove (22), and circular arc convex refractive groove (23) are on the same straight line and coaxially correspond to the light-emitting center of the corresponding incident light source.

4. The light guide plate according to claim 2, characterized in that, The stepped refractive groove (22) adopts a stepped groove structure with at least three steps. The inclination angle of the refractive surface of each step increases sequentially along the direction of light propagation. It is used to decompose the incident light into multiple refracted light beams with different propagation angles and cover the dark area between adjacent incident light sources.

5. The light guide plate according to claim 1, characterized in that, The irregularly shaped light-emitting cover (2) is integrally injection molded from optical grade PMMA or PC material with high light transmittance, and the edge of the irregularly shaped light-emitting cover (2) is provided with assembly grooves (4) for assembly and positioning.

6. The light guide plate according to claim 1, characterized in that, The light-emitting surface of the irregularly shaped light-emitting cover (2) is provided with a microstructure diffusion layer. The microstructure diffusion layer is arranged opposite to the irregularly shaped refractive groove group to perform final homogenization of the refracted light and further eliminate the brightness difference of the light-emitting surface.

7. An LED backlight module, characterized in that, The LED backlight module uses a light guide plate as described in any one of claims 1-6, and further includes a back plate (1), a cover plate (3), and at least one set of light emitters (6); the irregularly shaped light-emitting cover (2) is fixedly installed between the back plate (1) and the cover plate (3), the light emitter (6) is located on the light-incident side of the irregularly shaped light-emitting cover (2), and the light emitted by the light emitter (6) is uniformly projected onto the light-emitting surface of the back plate (1) after being refracted at multiple angles by the irregularly shaped refractive groove group.

8. The LED backlight module according to claim 7, characterized in that, The end of the back plate (1) is fixedly installed with a docking component (5). The docking component (5) includes a power connector (51), a mounting hole (52), and a control connector (53). The power connector (51) is electrically connected to the light emitter (6). The control connector (53) is signal connected to the light emitter (6) through the power connector (51) and is used to adjust the light emission parameters of the light emitter (6). The mounting hole (52) is opened at both ends of the docking component (5) for the assembly of the backlight module.

9. The LED backlight module according to claim 7, characterized in that, The light-emitting body (6) adopts a surface-mount LED lamp bead. Multiple groups of light-emitting bodies (6) are arranged linearly and equally at intervals along the light-incident side of the irregular light-emitting cover (2). The spacing between two adjacent groups of light-emitting bodies (6) matches the arrangement spacing of the irregular refractive groove group.

10. The LED backlight module according to claim 7, characterized in that, The cover plate (3) is an optical grade light-transmitting cover plate. The contact surface between the cover plate (3) and the irregular light-emitting cover (2) is provided with an anti-glare coating. The edge of the cover plate (3) is interference-fitted with the inner wall of the assembly groove (4) of the edge of the irregular light-emitting cover (2).

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