Light guide plate and backlight module

Abstract

The application relates to the technical field of display, in particular to a light guide plate and a backlight module, which comprise a plate body and light emitting strips, the plate body comprises a light emitting surface, a plurality of the light emitting strips are arranged in parallel on the light emitting surface, the light emitting strip is a groove recessed on the light emitting surface, and the size of the light emitting strip close to the edge area of the light emitting surface is larger than that of the light emitting strip close to the central area of the light emitting surface. The application has the effect of eliminating the waist shadow on the premise of ensuring the brightness of the central area.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to a light guide plate and a backlight module. Background Technology

[0002] Existing backlight modules typically include a light-diffusing component and light-emitting units. The main function of the light-diffusing component is to homogenize the light emitted by the light-emitting units, enabling the light to be evenly distributed across the entire display screen. A typical light-diffusing component structure is a light-diffusing plate. Light-diffusing plates are usually made of transparent or semi-transparent materials, and they achieve a uniform illumination effect for the entire backlight module by diffusing and mixing the light emitted by the light-emitting units.

[0003] Traditional backlight modules often suffer from some degree of waist shadow, meaning a significant decrease in brightness at the edges of the backlight module. This phenomenon is primarily due to light divergence. While light from the central area diverges to both sides and receives light from both sides, light from the edge area, similarly diverging to both sides, only receives light from one side, resulting in reduced brightness in the edge region. To eliminate this edge brightness problem, current technologies typically employ a scheme to direct light from the central area towards the edges. This is achieved by adjusting the physical structure or optical properties of the light-diffusing plate to guide light from the central area to the edge, thereby increasing edge brightness and eliminating the waist shadow.

[0004] However, this existing solution introduces new problems. Because some light from the central area is diverted to the edge areas, the brightness of the central area decreases, which significantly affects the viewing experience in practice. Therefore, there is an urgent need for a backlight module that can eliminate shadows around the waist without affecting the display quality in the central area. Utility Model Content

[0005] To address the aforementioned issues and eliminate waist shadows while ensuring the display effect in the central area, this application provides a light guide plate.

[0006] The light guide plate provided in this application adopts the following technical solution: A light guide plate includes a plate body and light-emitting strips. The plate body includes a light-emitting surface. The plurality of light-emitting strips are arranged in parallel on the light-emitting surface. Each light-emitting strip is a groove recessed into the light-emitting surface. The size of the light-emitting strip near the edge of the light-emitting surface is larger than the size of the light-emitting strip near the center of the light-emitting surface.

[0007] Optionally, the width of the light-emitting strip decreases as it approaches the bottom of the light-emitting strip, and the rate of decrease slows down as it approaches the bottom of the light-emitting strip.

[0008] By adopting the above technical solution, the depth of the light-emitting strip in the edge region is greater than that in the central region. Compared with the central region, the light in the edge region diffuses to both sides less during the emission process, while the light in the sub-edge region still diffuses normally to both sides. The brightness in the central region remains unchanged, and the shadow on the waist is eliminated.

[0009] Optionally, the surface of the light guide plate that is directly opposite the light emitting surface is the light incident surface.

[0010] By adopting the above technical solution, the light-incident surface and the light-outcident surface of the light guide plate are aligned, which can be adapted to direct-lit backlight modules.

[0011] Optionally, all surfaces of the light guide plate, except for the light-incident surface or the light-exit surface, are provided with a reflective layer.

[0012] By adopting the above technical solution, light inside the plate will be reflected when it reaches the surfaces other than the light-emitting and light-receiving surfaces, thus increasing the utilization rate of light.

[0013] Secondly, this application also provides a light guide plate.

[0014] The light guide plate provided in this application adopts the following technical solution: A light guide plate includes a plate body and light-emitting strips. The plate body includes a light-emitting surface. The plurality of light-emitting strips are arranged in parallel on the light-emitting surface. The light-emitting strips are protruding ridges on the light-emitting surface. The size of the light-emitting strips near the edge region of the light-emitting surface is smaller than the size of the light-emitting strips near the center region of the light-emitting surface.

[0015] Optionally, the cross-section of the light-emitting strip is triangular, arc-sided triangular, or bow-shaped.

[0016] By adopting the above technical solution, the height of the light-emitting strip in the edge region is less than that in the central region. Compared with the central region, the light in the edge region diffuses to both sides less during the emission process, while the light in the sub-edge region still diffuses normally to both sides. The brightness in the central region remains unchanged, and the shadow on the waist is eliminated.

[0017] Optionally, one of the surfaces of the light guide plate adjacent to the light emitting surface is the light incident surface, and the extension direction of the light emitting strip is perpendicular to the light incident surface.

[0018] By adopting the above technical solution, the incident direction of the light guide plate is parallel to the extension direction of the light output strip, and there is no difference between the light output strip at the near light end and the far light end, which does not affect the modulation of light uniformity at the near light end and the far light end by the side-lit backlight module.

[0019] Optionally, the two surfaces of the light guide plate adjacent to the light emitting surface are light incident surfaces, and the two light incident surfaces face each other, with the extension direction of the light emitting strip perpendicular to the light incident surface.

[0020] By adopting the above technical solution, light is simultaneously input into the two opposing light-incident surfaces, resulting in greater light intensity output from the light-out surface and enhanced display brightness.

[0021] Optionally, all surfaces of the light guide plate, except for the light-incident surface or the light-exit surface, are provided with a reflective layer.

[0022] By adopting the above technical solution, light inside the plate will be reflected when it reaches the surfaces other than the light-emitting and light-receiving surfaces, thus increasing the utilization rate of light.

[0023] Thirdly, this application provides a backlight module.

[0024] The backlight module provided in this application adopts the following technical solution: A backlight module includes a light-emitting unit and a light-diffusing component, wherein the light-diffusing component includes a light guide plate provided by a first aspect or a second aspect.

[0025] By adopting the above technical solution, a backlight module adapted to the light guide plate is provided, eliminating the waist shadow in the display process of the backlight module.

[0026] In summary, this application includes at least one of the following beneficial technical effects: 1. The light-emitting strip is concave to the light-emitting surface. The greater the depth of the light-emitting strip, the more concentrated the light becomes. The depth of the light-emitting strip in the edge area is greater than that in the central area. Therefore, compared with the central area, the light in the edge area has a smaller proportion of dispersion to both sides during the emission process, while the light in the secondary edge area still disperses normally to both sides. The final result is that the brightness of the central area remains unchanged, the brightness of the secondary edge area approaches the brightness of the edge area, the brightness of the edge area increases, and the shadow on the waist is eliminated.

[0027] 2. The light-emitting strip protrudes from the light-emitting surface. The greater the height of the light-emitting strip, the more diffused the light. The height of the light-emitting strip in the edge area is less than that in the central area. Therefore, compared with the central area, the light in the edge area diffuses to both sides in a smaller proportion during the emission process, while the light in the secondary edge area still diffuses normally to both sides. The final result is that the brightness of the central area remains unchanged, the brightness of the secondary edge area approaches that of the edge area, the brightness of the edge area increases, and the shadow on the waist is eliminated.

[0028] 3. The setting of the light-emitting strip disrupts the flatness of the light-emitting surface, thus reducing the proportion of total internal reflection of light on the light-emitting surface, allowing more light to be emitted, thereby improving light utilization and light intensity. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of a light guide plate according to Embodiment 1 of this application; Figure 2 This is a side view of a light guide plate according to Embodiment 1 of this application; Figure 3 This is a brightness distribution diagram of the light-emitting surface in the existing technology; Figure 4 This is a brightness distribution diagram of the light-emitting surface of Embodiment 1 of this application; Figure 5 This is a schematic diagram of the overall structure of a light guide plate according to Embodiment 2 of this application.

[0030] Explanation of reference numerals in the attached drawings: 1. Plate body; 11. Light-emitting surface; 12. Light-incident surface; 2. Light-emitting strip; 21. First light-emitting strip; 22. Second light-emitting strip. Detailed Implementation

[0031] The following is in conjunction with the appendix Figure 1-5 This application will be described in further detail.

[0032] The issue of shadows around the edges of the display has existed for a long time. Due to the unique relative position of the edge area, regardless of the arrangement of the light source, even when the brightness of the entire light-emitting surface is roughly uniform, there is always a noticeable boundary between the brightness of the edge area and the area closer to the center. This significantly affects the user's viewing experience. In existing technologies, light-diffusing components are typically designed with special optical properties to guide the light from the central area to the edge area to compensate for the shadows.

[0033] However, such adjustments will lead to a decrease in brightness in the central area. Peak brightness is a crucial quality evaluation standard for both backlight modules and displays. During human viewing, due to the focusing properties of human vision, most attention is concentrated on the central part of the displayed image. Therefore, a decrease in brightness in the central area will have a noticeable negative impact on the user experience.

[0034] This application discloses a light guide plate.

[0035] Example 1 Reference Figure 1 , Figure 2 The light guide plate disclosed in this embodiment includes a plate body 1 and multiple light-emitting strips 2.

[0036] The plate 1 includes a light-emitting surface 11 and a light-incident surface 12. The light-emitting strips 2 are disposed on the light-emitting surface 11 of the plate 1, and the extension directions of each light-emitting strip 2 are parallel to each other. A perpendicular line is made on the light-emitting surface 11 to the extension direction of the light strip 2, and the perpendicular line is parallel to the light-incident surface 12.

[0037] Preferably, the light-emitting strips 2 are densely covered by the projection of the light-emitting surface 11 of the plate 1.

[0038] In this embodiment, the light-emitting strip 2 is a groove recessed into the light-emitting surface 11, including a first light-emitting strip 21 and a second light-emitting strip 22 located on both sides of the first light-emitting strip 21. The first light-emitting strip 21 has a first depth, and the second light-emitting strip 22 has a second depth. The cross-section of the first light-emitting strip 21 and the cross-section of the second light-emitting strip 22 have the same shape, and the first depth is less than the second depth.

[0039] The width of the light-emitting strip 2 decreases as it approaches the bottom of the light-emitting strip 2, and the rate of decrease slows down as it approaches the bottom of the light-emitting strip 2. In other words, the two sidewalls of each light-emitting strip 2 protrude toward each other.

[0040] For example, in this embodiment, the surface of the plate 1 opposite to the light-emitting surface 11 is the light-incident surface 12. The four surfaces of the plate 1 other than the light-incident surface 12 and the light-emitting surface 11 are provided with reflective layers. Specifically, reflective films are deposited on the four surfaces.

[0041] The implementation principle of Example 1 is as follows: This embodiment provides a light guide plate adapted to a direct-lit backlight module. Light enters the light guide plate directly through the light-incident surface 12 and then exits through the light-exiting surface 11. Because the setting of the light-exiting strip 2 disrupts the flatness of the light-exiting surface 11, the probability of total internal reflection of light on the light-exiting surface 11 is reduced, and a larger proportion of light can be emitted, thus improving the utilization rate of light.

[0042] The differentiated arrangement of the first light-emitting strip 21 and the second light-emitting strip 22 causes some directional distribution of light during emission. Compared with technical solutions where all light-emitting strips 2 have the same shape and size, the second light-emitting strip 22 in this embodiment has a greater depth, and the proportion of light radiating to both sides from the area corresponding to the second light-emitting strip 22 is smaller. This ensures that the brightness of the central part of the area corresponding to the first light-emitting strip 21 is not reduced, while the brightness of the sides of the area corresponding to the first light-emitting strip 21 is reduced. Furthermore, a smaller proportion of light radiates to both sides from the area corresponding to each second light-emitting strip 22. This makes the overall brightness of the area corresponding to the second light-emitting strip 22 closer to the brightness of the sides of the area corresponding to the first light-emitting strip 21, thus achieving uniformity of light in the sub-edge and edge areas.

[0043] It is important to note that, typically, the light guide plate contains a light-uniforming structure, such as a scattering microstructure on the light-incident surface 12, or light-uniforming particles uniformly mixed within the plate 1. The aforementioned implementation principle did not analyze the related effects because the primary function of the light-uniforming structure is to diffuse the light from the point source, transforming it into a surface light source when it exits from the light-exiting surface 11. The design of the light-uniforming structure affects the graininess of the light exiting from the light-exiting surface 11. Since there is no directional guidance of the light, whether or not the effect of the light-uniforming structure is considered will not affect the achievement of the effect of the light-exiting strip 2 in this application. As long as the second light-exiting strip 22 can diffuse more light to both sides, it can effectively reduce the shadows on the waist.

[0044] Please refer to the above as well. Figure 3 , Figure 4 Compared with existing dimming structures that disperse light from the central region to the edge region, the dimming in this embodiment does not reduce the brightness of the central region, but rather makes the brightness of the edge region and the sub-edge region uniform. By reducing the brightness of the sub-edge region and increasing the brightness of the edge region, a transition from the high brightness of the central region to the low brightness of the edge region is achieved.

[0045] In reality, the reason why waist shadows degrade the viewing experience is not primarily due to insufficient absolute brightness leading to a lack of information. Firstly, current UI designs and image compositions rarely include text information for reading in the edge areas; these areas are more often occupied by tab and window adjustment buttons, which, even when almost invisible, don't significantly impact user operation. Secondly, users rarely focus their attention on the content displayed at the edges; viewing this area relies mainly on peripheral vision—a cursory glance as the viewer moves towards the corresponding area—and doesn't serve a reading function. The main reason waist shadows result in a poor viewing experience lies in the abrupt change in relative brightness. There's a clear distinction between the brightness at the edge of the monitor and the inner area, which is why users easily notice the waist shadow defect.

[0046] In this embodiment, some light from the sub-edge region is diffused to the edge region, while the brightness of the central region remains unaffected. This eliminates the light-dark boundary caused by waist shadows while maintaining the brightness of the central region, which is typically a crucial factor determining display performance, assuming no significant defects in the displayed image. Compared to existing adjustment schemes, this embodiment achieves greater brightness and superior display performance in the central region without altering the light source configuration.

[0047] Furthermore, in this embodiment, some of the light from the secondary edge region is diffused to the edge region. Therefore, compared to a solution that simply increases the brightness of the edge region, this embodiment only needs to compensate for a lower absolute brightness in the edge region to achieve the effect of eliminating the light-dark boundary of the waist shadow.

[0048] Example 2 Reference Figure 5 The difference between this embodiment and Embodiment 1 is that the light-emitting strip 2 in this application is a protruding ridge protruding from the light-emitting surface 11 of the plate 1; the light-emitting surface 11 and the light-incident surface 12 in this application are not opposite to each other but are adjacent to each other, and the extension direction of the light-emitting strip 2 is perpendicular to the light-incident surface 12. The first light-emitting strip 21 has a first height, and the second light-emitting strip 22 has a second height, wherein the first height is greater than the second height.

[0049] The light-incident surface 12 can be one or two. If the plate 1 includes two light-incident surfaces 12, the two light-incident surfaces 12 are arranged opposite to each other.

[0050] For example, the cross-section of the light-emitting strip 2 is triangular, arc-sided triangular, or bow-shaped.

[0051] The implementation principle of Example 2 is as follows: In Embodiment 1, the light-emitting strip 2 is recessed into the light-emitting surface 11. The greater the depth of the light-emitting strip 2, the more concentrated the light becomes. In this embodiment, the light-emitting strip 2 protrudes from the light-emitting surface 11. The greater the height of the light-emitting strip 2, the more diffuse the light becomes. Embodiment 1 reduces the proportion of light diverging to both sides in the area corresponding to the second light-emitting strip 22 by increasing the depth of the light-emitting strip 2; this embodiment reduces the proportion of light diverging to both sides in the area corresponding to the second light-emitting strip 22 by decreasing the height of the light-emitting strip 2.

[0052] This embodiment provides a parallel implementation scheme for protruding light strips 2.

[0053] This application also discloses a backlight module.

[0054] Example 3 The backlight module disclosed in this embodiment includes a light-emitting unit and a light-diffusing component. The light-diffusing component includes a light guide plate disclosed in Embodiment 1 or Embodiment 2. The light-emitting unit and the light-incident surface 12 of the light guide plate are arranged facing each other.

[0055] The implementation principle of Example 3 is as follows: This embodiment provides a backlight module structure where the light emitted by the light-emitting unit is modulated by a light guide plate, increasing the brightness of the edge area of ​​the displayed image, decreasing the brightness of the sub-edge area, and keeping the brightness of the central area unchanged. This eliminates waist shadows while maintaining the brightness of the central area.

[0056] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A light guide plate, characterized in that, The plate includes a plate (1) and light-emitting strips (2). The plate (1) includes a light-emitting surface (11). A plurality of light-emitting strips (2) are arranged in parallel on the light-emitting surface (11). The light-emitting strips (2) are grooves recessed into the light-emitting surface (11). The size of the light-emitting strips (2) near the edge of the light-emitting surface (11) is larger than the size of the light-emitting strips (2) near the center of the light-emitting surface (11).

2. The light guide plate according to claim 1, characterized in that, The width of the light-emitting strip (2) decreases as it approaches the bottom of the light-emitting strip (2), and the rate of decrease slows down as it approaches the bottom of the light-emitting strip (2).

3. The light guide plate according to claim 1, characterized in that, The surface of the light guide plate that is directly opposite the light-emitting surface (11) is the light-incident surface (12).

4. The light guide plate according to any one of claims 1-3, characterized in that, All surfaces of the light guide plate, except for the light-incident surface (12) or the light-exit surface (11), are provided with a reflective layer.

5. A light guide plate, characterized in that, The plate includes a plate (1) and light-emitting strips (2). The plate (1) includes a light-emitting surface (11). A plurality of light-emitting strips (2) are arranged in parallel on the light-emitting surface (11). The light-emitting strips (2) are protruding ridges on the light-emitting surface (11). The size of the light-emitting strips (2) near the edge of the light-emitting surface (11) is smaller than the size of the light-emitting strips (2) near the center of the light-emitting surface (11).

6. The light guide plate according to claim 5, characterized in that, One of the surfaces of the light guide plate adjacent to the light-emitting surface (11) is the light-incident surface (12), and the extension direction of the light-emitting strip (2) is perpendicular to the light-incident surface (12).

7. The light guide plate according to claim 5, characterized in that, The two surfaces of the light guide plate adjacent to the light-emitting surface (11) are light-incident surfaces (12), and the two light-incident surfaces (12) face each other. The extension direction of the light-emitting strip (2) is perpendicular to the light-incident surface (12).

8. The light guide plate according to any one of claims 5-7, characterized in that, All surfaces of the light guide plate, except for the light-incident surface (12) or the light-exit surface (11), are provided with a reflective layer.

9. The light guide plate according to claim 5, characterized in that, The cross-section of the light-emitting strip (2) is triangular, arc-sided triangular, or bow-shaped.

10. A backlight module, characterized in that, It includes a light-emitting unit and a light-diffusing component, wherein the light-diffusing component includes a light guide plate as described in any one of claims 1-9.

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