Backlight module and display device

Abstract

The embodiment of the utility model provides a backlight module and a display device, and belongs to the technical field of display. The backlight module comprises a first light guide plate, a second light guide plate, at least one first light source and at least one second light source, a first backlight face is provided with a plurality of first areas and a plurality of second areas which are alternately arranged in the first direction, and the first backlight face comprises a plurality of first light guide net point structures; each first light guide net point structure is located in one first region; the second backlight face is provided with a plurality of third areas and a plurality of fourth areas which are alternately arranged in the first direction, the second backlight face comprises a plurality of second light guide lattice point structures, each second light guide lattice point structure is located in one third area, and the orthographic projection of each second area on the second backlight face is located in one third area; the orthographic projection of each fourth area on the first backlight face is located in one first area. According to the embodiment of the invention, the probability of generating light crosstalk can be reduced.

Description

Technical Field

[0001] This disclosure relates to the field of display technology, and in particular to a backlight module and display device. Background Technology

[0002] With the rapid development of the display industry, display devices are widely used in people's daily lives. For example, mobile phones, televisions, monitors, and tablet computers are all equipped with display devices. Display devices include structures such as liquid crystal display panels and backlight modules located on the back of the liquid crystal display panels.

[0003] In related technologies, a backlight module includes a light guide plate and a light source. The light guide plate has a backlight surface and a light-emitting surface facing opposite directions, as well as a light-incident surface connecting the backlight surface and the light-emitting surface. The backlight surface includes a light guide dot structure arranged across the entire surface, and the light source is located on one side of the light-incident surface.

[0004] Light emitted from the light source enters the light guide plate from the light incident surface and propagates within it. During propagation, total internal reflection is disrupted by the light guide dot structure covering the entire backlight surface, resulting in diffuse reflection. If the light emitting surface of the backlight module needs to be divided into multiple dimming zones to achieve independent brightness control for each zone, the entire surface of the light guide dot structure will cause light rays to interfere with each other between adjacent dimming zones, i.e., crosstalk. Crosstalk affects the precise brightness control of the dimming zones, thus impacting the display effect. Utility Model Content

[0005] This disclosure provides a backlight module and display device that can reduce the probability of light crosstalk. The technical solution is as follows:

[0006] On one hand, a backlight module is provided, including a first light guide plate, a second light guide plate, at least one first light source, and at least one second light source. The first light guide plate has opposite first backlight surfaces and first light-emitting surfaces, and at least one first light-incident surface connecting the first backlight surface and the first light-emitting surface. The first backlight surface has a plurality of first regions and a plurality of second regions alternately arranged along a first direction. The first backlight surface includes a plurality of first light guide dot structures, and each first light guide dot structure is located in one of the first regions. The second light guide plate has opposite second backlight surfaces and second light-emitting surfaces, and at least one first light-incident surface connecting the second backlight surface and the second light-emitting surface. At least one second light-incident surface of the light-emitting surface, the second backlight surface facing the first light-emitting surface, the second backlight surface having a plurality of third regions and a plurality of fourth regions alternately arranged along the first direction, the second backlight surface including a plurality of second light-guiding dot structures, and each second light-guiding dot structure being located in one of the third regions, the orthographic projection of each second region on the second backlight surface being located in one of the third regions, and the orthographic projection of each fourth region on the first backlight surface being located in one of the first regions; each first light source being located on one side of a first light-incident surface; each second light source being located on one side of a second light-incident surface.

[0007] Optionally, the orthographic projection of each of the first regions on the first backlight surface completely coincides with the orthographic projection of a fourth region on the first backlight surface, and the orthographic projection of each of the second regions on the first backlight surface completely coincides with the orthographic projection of a third region on the first backlight surface.

[0008] Optionally, the first light guide dot structure includes a plurality of first dots arranged in an array, and the density of the first dots in at least a portion of the first light-incident surface gradually increases along the direction away from the first light-incident surface; the second light guide dot structure includes a plurality of second dots arranged in an array, and the density of the second dots in at least a portion of the second light guide dot structure gradually increases along the direction away from the second light-incident surface.

[0009] Optionally, the density of the first dots in the first light guide dot structure is 20% to 60%; the density of the second dots in the second light guide dot structure is 20% to 60%.

[0010] Optionally, the first light-incident surface includes a plurality of first light-incident regions spaced apart along the first direction, the orthographic projection of each first light-incident region onto the first light-emitting surface lies in one of the first regions, the first light source includes a plurality of first light-emitting structures spaced apart along the first direction, and each first light-emitting structure lies in one of the first light-incident regions; the second light-incident surface includes a plurality of second light-incident regions spaced apart along the first direction, the orthographic projection of each second light-incident region onto the second light-emitting surface lies in one of the third regions, the second light source includes a plurality of second light-emitting structures spaced apart along the first direction, and each second light-emitting structure lies in one of the second light-incident regions.

[0011] Optionally, the first light-emitting structure includes a plurality of first light-emitting units arranged at intervals along the first direction, wherein the plurality of first light-emitting units in the same first light-emitting structure are used to emit light or turn off simultaneously; the second light-emitting structure includes a plurality of second light-emitting units arranged at intervals along the first direction, wherein the plurality of second light-emitting units in the same second light-emitting structure are used to emit light or turn off simultaneously.

[0012] Optionally, the backlight module includes two first light sources and two second light sources. The first light guide plate has two opposite first light incident surfaces, and the two first light sources are respectively located on one side of the two first light incident surfaces. The second light guide plate has two opposite second light incident surfaces, and the two second light sources are respectively located on one side of the two second light incident surfaces.

[0013] Optionally, the backlight module further includes a light-shielding structure, which is located at least between the first light source and the second light guide plate, and between the second light source and the first light guide plate.

[0014] Optionally, the first light-emitting surface includes a plurality of first strip-shaped protrusions arranged sequentially and connected along the first direction, the first strip-shaped protrusions extending along a second direction perpendicular to the first direction; the second light-emitting surface includes a plurality of second strip-shaped protrusions arranged sequentially and connected along the first direction, the second strip-shaped protrusions extending along the second direction.

[0015] Optionally, on a cross section perpendicular to the second direction, the cross-sectional shape of the first strip protrusion is arc-shaped, semi-circular, or triangular; the cross-sectional shape of the second strip protrusion is arc-shaped, semi-circular, or triangular.

[0016] Optionally, in a direction perpendicular to both the first and second directions, the maximum height of the first strip protrusion is 25 μm to 35 μm; the maximum height of the second strip protrusion is 25 μm to 35 μm.

[0017] Optionally, in the first direction, the distance between the center lines of two adjacent first strip protrusions is 140 μm to 160 μm; the distance between the center lines of two adjacent second strip protrusions is 140 μm to 160 μm.

[0018] Optionally, the backlight module further includes a reflective sheet located on the first backlight surface.

[0019] Optionally, in a direction perpendicular to the first backlight surface in the second region, the thickness of the first light guide plate is 1.4 mm to 1.6 mm; the thickness of the second light guide plate is 1.4 mm to 1.6 mm.

[0020] On the other hand, a display device is provided, including any of the aforementioned backlight modules and a liquid crystal display panel, wherein the liquid crystal display panel is located on the light-emitting side of the backlight module.

[0021] The beneficial effects of the technical solutions provided in this disclosure are:

[0022] In this embodiment of the present disclosure, by setting a first light guide plate and a second light guide plate, the first backlight surface of the first light guide plate has a plurality of first regions and a plurality of second regions arranged alternately along a first direction, and each first light guide dot structure of the first light guide plate is set in a first region. The second backlight surface of the second light guide plate has a plurality of third regions and a plurality of fourth regions arranged alternately along the first direction, and each second light guide dot structure of the second light guide plate is set in a third region. The orthographic projection of each second region on the second backlight surface is located in a third region, and the orthographic projection of each fourth region on the first backlight surface is located in a first region. That is, in the direction from the first backlight surface to the second backlight surface, the orthographic projection positions of the first light guide dot structure and the second light guide dot structure are staggered, and the first light guide dot structure and the second light guide dot structure are staggered.

[0023] In this way, when the light emitted by the first light source enters the first light guide plate from the first light incident surface and propagates, it will be diffusely reflected by the first light guide dot structure on the first backlight surface in the first region due to total internal reflection, so that it can exit from the first region. In the second region, since there is no first light guide dot structure, the light will be totally internally reflected by the first backlight surface and then continue to propagate in the first light guide plate, making it more difficult to exit from the second region. When the light emitted by the second light source enters the second light guide plate from the second light incident surface and propagates, it will be diffusely reflected by the second light guide dot structure on the second backlight surface in the third region due to total internal reflection, so that it can exit from the third region. In the fourth region, since there is no second light guide dot structure, the light will be totally internally reflected by the second backlight surface and then continue to propagate in the second light guide plate, making it more difficult to exit from the fourth region. Therefore, this reduces the probability of light interference between adjacent first and second regions in the first light guide plate, and between adjacent third and fourth regions in the second light guide plate. In other words, it reduces the probability of crosstalk of light on the light-emitting surface of the backlight module, i.e., the second light-emitting surface. This facilitates fine-grained brightness control of each third and fourth region of the backlight module and improves the display effect. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a partial structural schematic diagram of a backlight module provided in an embodiment of this disclosure;

[0026] Figure 2 This is a schematic diagram of the structure of a first light guide plate and a first light source provided in an embodiment of this disclosure;

[0027] Figure 3 This is a schematic diagram of the structure of a second light guide plate and a second light source provided in an embodiment of this disclosure;

[0028] Figure 4 This is a partial structural schematic diagram of a backlight module provided in an embodiment of this disclosure;

[0029] Figure 5 This is a schematic diagram of the structure of a first light guide plate and a second light guide plate provided in an embodiment of this disclosure;

[0030] Figure 6 This is a partial structural schematic diagram of a first light guide plate and a second light guide plate provided in an embodiment of this disclosure;

[0031] Figure 7 This is a schematic diagram of the structure of a display device provided in an embodiment of this disclosure.

[0032] Legend:

[0033] y, first direction x, second direction

[0034] 1000, Backlight Module 2000, LCD Display Panel

[0035] 10. First light guide plate; 11. First backlight surface; 110. First light guide dot structure

[0036] 1101, First Outlet 111, First Area 112, Second Area

[0037] 12. First light-emitting surface 120; First strip-shaped protrusion 13. First light-receiving surface

[0038] 20. Second light guide plate; 21. Second backlight surface; 210. Second light guide dot structure

[0039] 2101, Second Branch 211, Third Area 212, Fourth Area

[0040] 22. Second light-emitting surface; 220. Second strip-shaped protrusion; 23. Second light-incident surface.

[0041] 30. First light source; 31. First light-emitting structure; 311. First light-emitting unit

[0042] 40. Second light source; 41. Second light-emitting structure; 411. Second light-emitting unit

[0043] 50. First substrate

[0044] 60. Light-shielding structure; 61. Reflective sheet; 62. Back plate

[0045] 621. Base plate; 622. Side plate; 63. Optical film.

[0046] 64. Adhesive frame Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of this disclosure clearer, the embodiments of this disclosure will be described in further detail below with reference to the accompanying drawings.

[0048] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” “third,” and similar terms used in this patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an” or “a” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “comprising” or “including” and similar terms mean that the elements or objects preceding “comprising” or “including” encompass the elements or objects listed following “comprising” or “including” and their equivalents, and do not exclude other elements or objects. The terms “connected” or “linked” and similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms “upper,” “lower,” “left,” “right,” “top,” and “bottom,” etc., are used only to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described objects changes.

[0049] Figure 1 This is a partial structural schematic diagram of a backlight module provided in an embodiment of this disclosure. For example... Figure 1 As shown, the backlight module includes a first light guide plate 10, a second light guide plate 20, at least one first light source 30, and at least one second light source 40. The first light guide plate 10 has a first backlight surface 11 and a first light-emitting surface 12 facing each other, and at least one first light-incident surface 13 connecting the first backlight surface 11 and the first light-emitting surface 12. The second light guide plate 20 has a second backlight surface 21 and a second light-emitting surface 22 facing each other, and at least one second light-incident surface 23 connecting the second backlight surface 21 and the second light-emitting surface 22, with the second backlight surface 21 facing the first light-emitting surface 12.

[0050] Figure 2 This is a schematic diagram of the structure of a first light guide plate and a first light source provided in an embodiment of this disclosure. Figure 2 As shown, the first backlight surface 11 has a plurality of first regions 111 and a plurality of second regions 112 arranged alternately along the first direction y. The first backlight surface 11 includes a plurality of first light guide dot structures 110, and each first light guide dot structure 110 is located in a first region 111. Each first light source 30 is located on one side of a first light incident surface 13.

[0051] Figure 3 This is a schematic diagram of the structure of a second light guide plate and a second light source provided in an embodiment of this disclosure. Figure 3As shown, the second backlight surface 21 has a plurality of third regions 211 and a plurality of fourth regions 212 arranged alternately along the first direction y. The second backlight surface 21 includes a plurality of second light guide dot structures 210, and each second light guide dot structure 210 is located in a third region 211. Each second light source 40 is located on one side of a second light incident surface 23.

[0052] See Figure 2 and Figure 3 Each second region 112 has its orthographic projection on the second backlight surface 21 located in a third region 211, and each fourth region 212 has its orthographic projection on the first backlight surface 11 located in a first region 111. Here, "each second region 112's orthographic projection on the second backlight surface 21 located in a third region 211" means that the entire orthographic projection of each second region 112 on the second backlight surface 21 is covered by the orthographic projection of the third region 211 on the second backlight surface 21. Similarly, "each fourth region 212's orthographic projection on the first backlight surface 11 located in a first region 111" means that the entire orthographic projection of each fourth region 212 on the first backlight surface 11 is covered by the orthographic projection of the first region 111 on the first backlight surface 11.

[0053] In this embodiment of the disclosure, by setting a first light guide plate 10 and a second light guide plate 20, each first light guide dot structure 110 of the first light guide plate 10 is disposed in a first region 111, and each second light guide dot structure 210 of the second light guide plate 20 is disposed in a third region 211. The orthographic projection of each second region 112 on the second backlight surface 21 is located in a third region 211, and the orthographic projection of each fourth region 212 on the first backlight surface 11 is located in a first region 111. That is, in the direction from the first backlight surface 11 to the second backlight surface 21, the orthographic projection positions of the first light guide dot structure 110 and the second light guide dot structure 210 are staggered, and the first light guide dot structure 110 and the second light guide dot structure 210 are staggered. For example, in Figure 2 and Figure 3 In the top view shown, the orthographic projections of the first light guide dot structure 110 and the second light guide dot structure 210 in the backlight module are arranged as follows, from top to bottom: the orthographic projection of the second light guide dot structure 210, the orthographic projection of the first light guide dot structure 110, the orthographic projection of the second light guide dot structure 210, the orthographic projection of the first light guide dot structure 110, and so on...

[0054] Thus, when the light emitted by the first light source enters the first light guide plate 10 from the first light incident surface and propagates, it undergoes diffuse reflection in the first region 111 due to the total internal reflection disrupted by the first light guide dot structure 110 of the first backlight surface 11, allowing it to exit from the first region 111. In the second region 112, since the first light guide dot structure 110 is not provided, the light undergoes total internal reflection on the first backlight surface 11 and continues to propagate in the first light guide plate 10, making it more difficult to exit from the second region 112. When the light emitted by the second light source enters the second light guide plate 20 from the second light incident surface and propagates, it undergoes diffuse reflection in the third region 211 due to the total internal reflection disrupted by the second light guide dot structure 210 of the second backlight surface 21, allowing it to exit from the third region 211. In the fourth region 212, since the second light guide dot structure 210 is not provided, the light undergoes total internal reflection on the second backlight surface 21 and continues to propagate in the second light guide plate 20, making it more difficult to exit from the fourth region 212. Therefore, this reduces the probability of light interference between adjacent first and second regions 111 and 112 in the first light guide plate 10, and between adjacent third and fourth regions 212 in the second light guide plate 20. This also reduces the probability of crosstalk occurring on the light-emitting surface 22 of the backlight module, thereby facilitating precise brightness control of each third and fourth region 211 and improving display performance. Furthermore, this edge-lit backlight module is less expensive than a direct-lit backlight module.

[0055] Optionally, the orthographic projection of each first region 111 on the first backlight surface 11 completely coincides with the orthographic projection of a fourth region 212 on the first backlight surface 11, and the orthographic projection of each second region 112 on the first backlight surface 11 completely coincides with the orthographic projection of a third region 211 on the first backlight surface 11. That is, in the direction from the first backlight surface 11 to the second backlight surface 21, the orthographic projection positions of the first light guide dot structure 110 and the second light guide dot structure 210 are completely complementary and staggered, with no overlapping portions. For example, in... Figure 2 and Figure 3In the top view shown, the orthographic projections of the first light guide dot structure 110 and the second light guide dot structure 210 in the backlight module are arranged as follows, from top to bottom: the orthographic projection of the second light guide dot structure 210, the orthographic projection of the first light guide dot structure 110, the orthographic projection of the second light guide dot structure 210, the orthographic projection of the first light guide dot structure 110, and so on. Furthermore, each orthographic projection of the first light guide dot structure 110 and the second light guide dot structure 210 is closely connected without any overlap. This way, when it is necessary to achieve individual brightness control of each third region 211 and fourth region 212 on the light-emitting surface of the backlight module, the probability of light crosstalk caused by projection overlap between the first region 111 (i.e., the fourth region 212) containing the first light guide dot structure 110 and the third region 211 (containing the second light guide dot structure 210) can be further reduced, thereby effectively achieving fine-grained brightness control of each third region 211 and fourth region 212 of the backlight module.

[0056] In other embodiments, the orthographic projection of each second region 112 on the second backlight surface 21 lies inside a third region 211, and the orthographic projection of each fourth region 212 on the first backlight surface 11 lies inside a first region 111. The orthographic projections of each first region 111 on the first backlight surface 11 and the orthographic projections of the third region 211 on the first backlight surface 11 partially overlap. This reduces the probability of crosstalk compared to arranging a light guide dot matrix across the entire surface of the light guide plate. For example, the orthographic projections of each first region 111 on the first backlight surface 11 and the orthographic projections of the third region 211 on the first backlight surface 11 may have a first overlapping portion.

[0057] For example, the ratio of the area of ​​the first overlapping portion to the area of ​​the first region 111 is greater than 0 and less than or equal to 1 / 3, and the ratio of the area of ​​the first overlapping portion to the area of ​​the third region 211 is greater than 0 and less than or equal to 1 / 3. For instance, the ratio of the area of ​​the first overlapping portion to the area of ​​the first region 111 can be 1 / 6, 1 / 5, or 1 / 4, etc., and the ratio of the area of ​​the first overlapping portion to the area of ​​the third region 211 can be 1 / 6, 1 / 5, or 1 / 4, etc.

[0058] See Figure 2 and Figure 3 The first light-guiding dot structure 110 includes a plurality of first dots 1101 arranged in an array. Along the direction away from the first light-incident surface 13, the density of the first dots 1101 in at least a portion of the first light-guiding dot structure 110 gradually increases. The second light-guiding dot structure 210 includes a plurality of second dots 2101 arranged in an array. Along the direction away from the second light-incident surface 23, the density of the second dots 2101 in at least a portion of the second light-guiding dot structure 210 gradually increases.

[0059] Since more light can be emitted through diffuse reflection by the light guide dot structure when closer to the light source, the density of the first dot 1101 (close to the first light-incident surface 13) and the second dot 2101 (close to the second light-incident surface 23) near the first light source 30 and the second dot 2101 (close to the second light-incident surface 23) is set to be smaller, while the density of the first dot 1101 (far from the first light-incident surface 13) and the second dot 2101 (far from the second light-incident surface 23) far from the first light source 30 and the second dot 2101 (far from the second light-incident surface 23) is set to be larger. This can ensure that the light output of each area of ​​the backlight module is roughly the same, thereby improving the overall light output uniformity of the backlight module and improving the uniformity of the display image.

[0060] like Figure 2 and Figure 3 As shown, the backlight module includes two first light sources 30 and two second light sources 40. The first light guide plate 10 has two opposite first light incident surfaces 13, and the two first light sources 30 are respectively located on one side of the two first light incident surfaces 13. The second light guide plate 20 has two opposite second light incident surfaces 23, and the two second light sources 40 are respectively located on one side of the two second light incident surfaces 23. The dual-side light incident method can improve the light emission uniformity of the backlight module.

[0061] For example, the first light guide plate 10 has a rectangular orthographic projection on the first backlight surface 11, and its two first light-incident surfaces 13 are located on the sides of the rectangle containing the two opposite short sides. The second light guide plate 20 has a rectangular orthographic projection on the second backlight surface 21, and its two second light-incident surfaces 23 are located on the sides of the rectangle containing the two opposite short sides. For example, the two first light-incident surfaces 13 are located on the left and right sides of the first light guide plate 10, and the two second light-incident surfaces 23 are located on the left and right sides of the second light guide plate 20.

[0062] For example, when the first light guide plate 10 has two opposite first light incident surfaces 13, the density of the first dots 1101 in the first light guide dot structure 110 gradually increases and then gradually decreases in the direction from one first light incident surface 13 to the other. When the second light guide plate 20 has two opposite second light incident surfaces 23, the density of the second dots 2101 in the second light guide dot structure 210 gradually increases and then gradually decreases in the direction from one second light incident surface 23 to the other.

[0063] In other embodiments, the backlight module may also include only one first light source 30 and one second light source 40. The first light guide plate 10 has a first light incident surface 13, and the second light guide plate 20 has a second light incident surface 23. The first light source 30 is located on one side of the first light incident surface 13, and the second light source 40 is located on one side of the second light incident surface 23. For example, the first light incident surface 13 is located on the left side of the first light guide plate 10, and the second light incident surface 23 is located on the left side of the second light guide plate 20; or, the first light incident surface 13 is located on the right side of the first light guide plate 10, and the second light incident surface 23 is located on the right side of the second light guide plate 20; or, the first light incident surface 13 is located on the right side of the first light guide plate 10, and the second light incident surface 23 is located on the left side of the second light guide plate 20, etc. This disclosure does not limit this.

[0064] For example, when the first light guide plate 10 has a first light incident surface 13, the density of the first dots 1101 in the first light guide dot structure 110 gradually increases along the direction away from the first light incident surface 13. When the second light guide plate 20 has a second light incident surface 23, the density of the second dots 2101 in the second light guide dot structure 210 gradually increases along the direction away from the second light incident surface 23.

[0065] For example, each first site 1101 has the same area. Each second site 2101 has the same area.

[0066] In other embodiments, the areas of the various first dots 1101 may not be exactly the same. The areas of the various second dots 2101 may not be exactly the same.

[0067] In this embodiment of the disclosure, the density of the first dot 1101 refers to the ratio of the sum of the areas of the first dots 1101 arranged in the first preset area to the first preset area, and the density of the second dot 2101 refers to the ratio of the sum of the areas of the second dots 2101 arranged in the first preset area to the first preset area.

[0068] When the areas of each first dot 1101 and each second dot 2101 are the same, the density of the first dots 1101 can be controlled by setting the arrangement spacing of multiple first dots 1101, and the density of the second dots 2101 can be controlled by setting the arrangement spacing of multiple second dots 2101. For example, in the region near the first light source 30, i.e., near the first light-receiving surface 13, the spacing between two adjacent first dots 1101 is larger, while in the region far from the first light source 30, i.e., far from the first light-receiving surface 13, the spacing between two adjacent first dots 1101 is smaller; similarly, in the region near the second light source 40, i.e. near the second light-receiving surface 23, the spacing between two adjacent second dots 2101 is larger, while in the region far from the second light source 40, i.e., far from the second light-receiving surface 23, the spacing between two adjacent second dots 2101 is smaller.

[0069] When the areas of each first dot 1101 are not exactly the same, and the areas of each second dot 2101 are not exactly the same, the density of the first dot 1101 can be controlled by setting the area of ​​the first dot 1101 in different regions of the first light guide dot structure 110, and the density of the second dot 2101 can be controlled by setting the area of ​​the second dot 2101 in different regions of the second light guide dot structure 210. For example, in the first light guide dot structure 110, the spacing between two adjacent first dots 1101 is the same. In the region near the first light source 30, i.e., near the first light incident surface 13, the area of ​​the first dot 1101 is smaller, and in the region away from the first light source 30, i.e., away from the first light incident surface 13, the area of ​​the first dot 1101 is larger. In the second light guide dot structure 210, the spacing between two adjacent second dots 2101 is the same. In the region near the second light source 40, i.e. near the second light incident surface 23, the area of ​​the second dot 2101 is smaller, and in the region away from the second light source 40, i.e., away from the second light incident surface 23, the area of ​​the second dot 2101 is larger.

[0070] Optionally, the density of the first dot 1101 in the first light guide dot structure 110 is 20% to 60%. The density of the second dot 2101 in the second light guide dot structure 210 is 20% to 60%. The density of the first dot 1101 and the second dot 2101 within this range can improve the overall light emission uniformity of the backlight module, and will not affect the display effect due to the setting of the first dot 1101 and the second dot 2101.

[0071] For example, the density of the first dot 1101 in the first dot structure 110 can be 20%, 40%, or 60%, etc.

[0072] For example, the density of the second dot 2101 in the second dot structure 210 can be 20%, 40%, or 60%, etc.

[0073] In other embodiments, the density of the first dot 1101 can also be represented by the number of first dots 1101 arranged per unit area, and the density of the second dot 2101 can also be represented by the number of second dots 2101 arranged per unit area. This disclosure does not limit this. For example, if the area of ​​each first dot 1101 is the same, and the area of ​​each second dot 2101 is the same, then the density of the first dots 1101 is lower if the number of first dots 1101 arranged per unit area is smaller, and the density of the first dots 1101 is higher if the number of first dots 1101 arranged per unit area is larger. Similarly, the density of the second dots 2101 is lower if the number of second dots 2101 arranged per unit area is smaller, and the density of the second dots 2101 is higher if the number of second dots 2101 arranged per unit area is larger.

[0074] Optionally, the first dot 1101 can be an elliptical dot, a circular dot, or a wedge-shaped dot, etc. The first dot 1101 is recessed toward the side of the first backlight surface 1101 that is closer to the first light-emitting surface, or the first dot 1101 is protruding toward the side of the first backlight surface 1101 that is away from the first light-emitting surface.

[0075] Optionally, the second halftone dot 2101 can be an elliptical halftone dot, a circular halftone dot, or a wedge-shaped halftone dot, etc. The second halftone dot 2101 is recessed towards the side of the second backlight surface 2101 closer to the second light-emitting surface, or the second halftone dot 2101 is protruding towards the side of the second backlight surface 2101 away from the second light-emitting surface.

[0076] Figure 4 This is a partial structural schematic diagram of a backlight module provided in an embodiment of this disclosure. Figures 1 to 4 As shown, the first light-incident surface 13 includes a plurality of first light-incident regions arranged at intervals along the first direction y, and the orthographic projection of each first light-incident region on the first light-emitting surface 12 is located in a first region 111. The first light source 30 includes a plurality of first light-emitting structures 31 arranged at intervals along the first direction y, and each first light-emitting structure 31 is located in a first light-incident region. The second light-incident surface 23 includes a plurality of second light-incident regions arranged at intervals along the first direction y, and the orthographic projection of each second light-incident region on the second light-emitting surface 22 is located in a third region 211. The second light source 40 includes a plurality of second light-emitting structures 41 arranged at intervals along the first direction y, and each second light-emitting structure 41 is located in a second light-incident region.

[0077] That is, the first light-incident area where the first light-emitting structure 31 is located corresponds to the first region 111 where the first light-guiding dot structure 110 is provided, and the second light-incident area where the second light-emitting structure 41 is located corresponds to the third region 211 where the second light-guiding dot structure 210 is provided. This can further reduce the probability of light emitted by the first light source 30 exiting from the second region 112 and the probability of light emitted by the second light source 40 exiting from the fourth region 212, thereby further reducing the probability of light crosstalk, and is also beneficial to achieve individual brightness control of each third region 211 and fourth region 212 on the light-emitting surface of the backlight module through the first light-emitting structure 31 and the second light-emitting structure 41.

[0078] It should be noted that, Figure 1 The first light source 30 and the second light source 40 shown are merely schematic representations of the cross-sectional projection positions of the first light source 30 and the second light source 40, and do not imply a structural limitation that the first light-emitting structure in the first light source 30 and the second light-emitting structure in the second light source 40 are located on the same cross-section. That is, as shown... Figure 4 As shown, on a cross section perpendicular to the first direction y, the first light-emitting structure 31 in the first light source 30 and the second light-emitting structure 41 in the second light source 40 are located on different cross sections.

[0079] like Figure 4 As shown, the first light-emitting structure 31 includes a plurality of first light-emitting units 311 arranged at intervals along the first direction y, and the plurality of first light-emitting units 311 in the same first light-emitting structure 31 are used to emit light or turn off simultaneously. The second light-emitting structure 41 includes a plurality of second light-emitting units 411 arranged at intervals along the first direction y, and the plurality of second light-emitting units 411 in the same second light-emitting structure 41 are used to emit light or turn off simultaneously.

[0080] Each first light-emitting structure 31 is provided with multiple first light-emitting units 311, and each second light-emitting structure 41 is provided with multiple second light-emitting units 411, which can ensure a good light-emitting effect of the backlight module. The multiple first light-emitting units 311 in the same first light-emitting structure 31 are used to emit light or turn off simultaneously, and the multiple second light-emitting units 411 in the same second light-emitting structure 41 are used to emit light or turn off simultaneously. This is beneficial for achieving individual brightness control of each third area 211 and fourth area 212 of the backlight module by scanning the backlight, thereby improving the display effect. For example, scanning can be performed from left to right along the first direction y, and each light-emitting structure can be controlled to emit light or turn off in the following order: second light-emitting structure 41, first light-emitting structure 31, second light-emitting structure 41, first light-emitting structure 31... During the scanning process, multiple first light-emitting units 311 in the same first light-emitting structure 31 emit light or turn off simultaneously, multiple second light-emitting units 411 in the same second light-emitting structure 41 emit light or turn off simultaneously, each first light-emitting structure 31 controls the brightness of a corresponding first region 111, that is, the brightness of the fourth region 212 on the light-emitting surface of the backlight module, and each second light-emitting structure 41 controls the brightness of a corresponding third region 211.

[0081] See Figures 2 to 4 The backlight module also includes two first substrates 50. The first light source 30 and the second light source 40, located on the same side of the first light guide plate 10 and the second light guide plate 20, are located on one first substrate 50. The first substrate 50 is used to supply power to the first light source 30 and the second light source 40.

[0082] For example, the first substrate 50 is a printed circuit board or a flexible circuit board.

[0083] In other embodiments, the backlight module further includes two second substrates, with each first light source 30 located on a first substrate 50 and each second light source 40 located on a second substrate. That is, the first light source 30 and the second light source 40 may be located on different substrates, and this disclosure does not limit this.

[0084] Figure 5 This is a schematic diagram of the structure of a first light guide plate and a second light guide plate provided in an embodiment of this disclosure. Figure 5 Part (a) can represent a schematic diagram of the structure of the first light guide plate. Figure 5 Part (b) can represent a schematic diagram of the structure of the second light guide plate. Figure 6 This is a partial structural schematic diagram of a first light guide plate and a second light guide plate provided in an embodiment of this disclosure. Figure 6 The arrows in the diagram indicate the propagation paths of portions of the light rays in the first light guide plate 10 and the second light guide plate 20. (See also...) Figure 5 and Figure 6The first light-emitting surface 12 includes a plurality of first strip-shaped protrusions 120 arranged sequentially and connected along a first direction y. The first strip-shaped protrusions 120 extend along a second direction x, which is perpendicular to the first direction y. The second light-emitting surface 22 includes a plurality of second strip-shaped protrusions 220 arranged sequentially and connected along the first direction y. The second strip-shaped protrusions 220 extend along the second direction x.

[0085] By setting multiple first strip-shaped protrusions 120 and multiple second strip-shaped protrusions 220 on the entire surface, the emission range of light from the first light-emitting surface 12 and the second light-emitting surface 22 can be narrowed, and the probability of total internal reflection of light from the first light-emitting surface 12 and the second light-emitting surface 22 can be reduced. This helps to reduce the probability of crosstalk between adjacent first regions 111 and second regions 112 and between adjacent third regions 211 and fourth regions 212.

[0086] Figure 6 In the first light guide plate 10, when the light emitted from the first light source enters from the first light-incident surface and propagates, it undergoes diffuse reflection in the first region 111 due to total internal reflection disrupted by the first light-guiding dot structure 110 on the first backlight surface 11. The light then propagates towards the first light-emitting surface 12. Multiple first strip-shaped protrusions 120 reduce the probability of this portion of the light undergoing total internal reflection again on the first light-emitting surface 12 and propagating to the adjacent second region 112, thus allowing most of the light to directly exit from the first light-emitting surface 12 of the first region 111 to the second light guide plate 20. After passing through the second light guide plate 20, the light exits from the second light-emitting surface 22 of the fourth region 212 of the second light guide plate 20. In the second region 112, since the first light-guiding dot structure 110 is not present, the light undergoes total internal reflection on the first backlight surface 11 and continues to propagate in the first light guide plate 10, making it more difficult to exit from the second region 112. Similarly, when the light emitted from the second light source enters the second light guide plate 20 from the second light incident surface, it undergoes diffuse reflection in the third region 211 due to total internal reflection disrupted by the second light guide dot structure 210 of the second backlight surface 21. The light then travels towards the second light emitting surface 22. Multiple second strip-shaped protrusions 220 reduce the likelihood of this portion of the light undergoing total internal reflection again on the second light emitting surface 22 and propagating into the adjacent fourth region 212, thus allowing most of the light to exit directly from the second light emitting surface 22 of the third region 211. In the fourth region 212, since the second light guide dot structure 210 is not present, the light undergoes total internal reflection on the second backlight surface 21 and continues to propagate within the second light guide plate 20, making it more difficult for it to exit from the fourth region 212.

[0087] By cooperating with the first dot structure 110, the second dot structure 210, multiple first strip protrusions 120, and multiple second strip protrusions 220, it can be ensured that after the light emitted by the first light source propagates in the first light guide plate 10, most of the light exits from the corresponding first region 111. After the light emitted by the second light source propagates in the second light guide plate 20, most of the light exits from the corresponding third region 211. This reduces the probability of the light emitted by the first light source exiting from the second region 112 and the fourth region 212, thus reducing crosstalk. Furthermore, since the second light guide dot structure 210 is not set in the fourth region 212, the propagation path of the light from the first region 111 to the fourth region 212 of the second light guide plate 20 is not significantly affected. Therefore, the light will ultimately exit from the light-emitting surface of the backlight module, namely the second light-emitting surface 22, thus ensuring a good overall light emission effect of the backlight module.

[0088] Optionally, on a cross-section perpendicular to the second direction x, the cross-sectional shape of the first strip protrusion 120 is arc-shaped, semi-circular, or triangular. The cross-sectional shape of the second strip protrusion 220 is also arc-shaped, semi-circular, or triangular. These shapes of the first strip protrusion 120 and the second strip protrusion 220 can effectively converge the emission range of light rays.

[0089] Figure 5 and Figure 6 In this embodiment, the cross-sectional shape of the first strip protrusion 120 and the second strip protrusion 220 is arc-shaped, which is only an example. In other embodiments, the cross-sectional shape of the first strip protrusion 120 and the second strip protrusion 220 may also adopt other shapes, as long as they can achieve the effect of converging the emission range of light, and this disclosure does not impose any restrictions on this.

[0090] Optionally, in a direction perpendicular to the first direction y and the second direction x, the maximum height H1 of the first strip protrusion 120 is 25 μm to 35 μm. The maximum height H2 of the second strip protrusion 220 is 25 μm to 35 μm. Here, the maximum height H1 of the first strip protrusion 120 refers to the maximum value of the height of the first strip protrusion 120, and the maximum height H2 of the second strip protrusion 220 refers to the maximum value of the height of the second strip protrusion 220. By setting the first strip protrusion 120 and the second strip protrusion 220 to a relatively high height, the probability of total internal reflection of light at the first light-emitting surface 12 and the second light-emitting surface 22 can be effectively reduced.

[0091] For example, the maximum height H1 of the first strip protrusion 120 can be 25μm, 30μm or 35μm, etc.

[0092] For example, the maximum height H2 of the second strip protrusion 220 can be 25μm, 30μm or 35μm, etc.

[0093] Optionally, in the first direction y, the distance D1 between the center lines of two adjacent first strip protrusions 120 is 140 μm to 160 μm. The distance D2 between the center lines of two adjacent second strip protrusions 220 is 140 μm to 160 μm. Within this range of D1 and D2, the first strip protrusions 120 and the second strip protrusions 220 can effectively converge the emission range of light from the first light-emitting surface 12 and the second light-emitting surface 22, and effectively reduce the probability of total internal reflection of light from the first light-emitting surface 12 and the second light-emitting surface 22.

[0094] For example, the distance D1 between the center lines of two adjacent first strip protrusions 120 can be 140μm, 150μm or 160μm, etc.

[0095] For example, the distance D2 between the center lines of two adjacent second strip protrusions 220 can be 140μm, 150μm or 160μm, etc.

[0096] Optionally, in the direction perpendicular to the first backlight surface 11 in the second region 112, the thickness H3 of the first light guide plate 10 is 1.4 mm to 1.6 mm. The thickness H4 of the second light guide plate 20 is 1.4 mm to 1.6 mm. With H3 and H4 within this range, crosstalk of light can be effectively reduced while ensuring that the total thickness of the backlight module is small.

[0097] For example, the thickness H3 of the first light guide plate 10 can be 1.4mm, 1.5mm or 1.6mm, etc.

[0098] For example, the thickness H4 of the second light guide plate 20 can be 1.4mm, 1.5mm or 1.6mm, etc.

[0099] See you again Figure 1 The backlight module also includes a light-shielding structure 60, which is located at least between the first light source 30 and the second light guide plate 20, and between the second light source 40 and the first light guide plate 10. The light-shielding structure 60 can reduce the probability of light emitted by the first light source 30 directly hitting the second light guide plate 20, and light emitted by the second light source 40 directly hitting the first light guide plate 10, thus reducing the likelihood of light shadows.

[0100] For example, the light-shielding structure 60 is also located on the first substrate 50 surrounding the first light source 30. That is, the light-shielding structure 60 can also be located around each of the first light-emitting units in the first light source 30, and cover the surface of the first substrate 50 near the first light source 30. It can be understood that the light-shielding structure 60 on the surface of the first substrate 50 is provided with multiple openings, and each first light-emitting unit is located in one opening.

[0101] For example, the light-shielding structure 60 also extends between a portion of the first light guide plate 10 and the second light guide plate 20.

[0102] For example, the light-shielding structure 60 is made of a light-absorbing material. For instance, the light-shielding structure 60 can be a light-shielding adhesive layer or a black ink layer, etc.

[0103] like Figure 1 As shown, the backlight module also includes a reflective sheet 61, which is located on the first backlight surface 11. The reflective sheet 61 can reflect the light rays incident on the first backlight surface 11, allowing the light rays to re-enter the first light guide plate 10, thereby improving the light output efficiency of the backlight module.

[0104] For example, when the first light source 30 and the second light source 40 emit light, the ratio of the current in the first light source 30 to the current in the second light source 40 is 0.9 to 1.1. Since the light from the first light guide plate 10 exits from the light-emitting surface of the backlight module, i.e., the second light-emitting surface 22, it passes through the second light guide plate 20. If the light from the second light guide plate 20 is reflected by the reflector 61 and then exits from the light-emitting surface of the backlight module, it will pass through the first light guide plate 10 twice. Since the light paths and light loss conditions of the first light source 30 and the second light source 40 are different, the ratio of the current in the first light source 30 to the current in the second light source 40 within this range is beneficial to ensuring the uniformity of light emission from the backlight module.

[0105] For example, when both the first light source 30 and the second light source 40 emit light, the ratio of the current in the first light source 30 to the current in the second light source 40 can be 0.9, 1, or 1.1, etc.

[0106] Optionally, the backlight module also includes a back plate 62, which is located on the side of the reflective sheet 61 away from the first light guide plate 10, on the side of the first light source 30 away from the first light guide plate 10, and on the side of the second light source 40 away from the second light guide plate 20.

[0107] For example, the backplate 62 includes a connected base plate 621 and a side plate 622, the side plate 622 being arranged around and connected to the side of the base plate 621. The base plate 621 is located on the side of the reflector 61 away from the first light guide plate 10, and the side plate 622 is located on the side of the first light source 30 away from the first light guide plate 10 and the side of the second light source 40 away from the second light guide plate 20, and is located around the first light guide plate 10 and the second light guide plate 20.

[0108] Optionally, the backlight module also includes an optical film 63 located on the second light-emitting surface 22.

[0109] For example, the optical film 63 may include at least one of a reflective film, an anti-reflective film, a polarizing film, and an optical microlens film.

[0110] Optionally, the backlight module also includes a frame 64, which is located around the first light guide plate 10 and the second light guide plate 20 and is connected to the side plate 622.

[0111] Figure 7 This is a schematic diagram of the structure of a display device provided in an embodiment of this disclosure. Figure 7 As shown, the display device includes any of the aforementioned backlight modules 1000 and liquid crystal display panels 2000, with the liquid crystal display panels 2000 located on the light-emitting side of the backlight modules 1000.

[0112] For example, the display device can be any product or component with display function, such as a mobile phone, tablet computer, television, monitor, laptop computer, digital photo frame, or navigator.

[0113] The above description is not intended to limit this disclosure in any way. Although this disclosure has been disclosed above through embodiments, it is not intended to limit this disclosure. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the technical solution of this disclosure. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of this disclosure without departing from the content of the technical solution of this disclosure shall still fall within the scope of the technical solution of this disclosure.

Claims

1. A backlight module, characterized in that, It includes a first light guide plate, a second light guide plate, at least one first light source, and at least one second light source. The first light guide plate has a first backlight surface and a first light-emitting surface opposite to each other, and at least one first light-incident surface connecting the first backlight surface and the first light-emitting surface. The first backlight surface has a plurality of first regions and a plurality of second regions arranged alternately along a first direction. The first backlight surface includes a plurality of first light guide dot structures, and each first light guide dot structure is located in one of the first regions. The second light guide plate has a second backlight surface and a second light-emitting surface opposite to each other, and at least one second light-incident surface connecting the second backlight surface and the second light-emitting surface. The second backlight surface faces the first light-emitting surface. The second backlight surface has a plurality of third regions and a plurality of fourth regions arranged alternately along the first direction. The second backlight surface includes a plurality of second light guide dot structures, and each second light guide dot structure is located in one of the third regions. The orthographic projection of each second region on the second backlight surface is located in one of the third regions, and the orthographic projection of each fourth region on the first backlight surface is located in one of the first regions. Each of the first light sources is located on one side of a first light-incident surface; Each of the second light sources is located on one side of a second light-incident surface.

2. The backlight module according to claim 1, characterized in that, The orthographic projection of each of the first regions on the first backlight surface completely coincides with the orthographic projection of a fourth region on the first backlight surface, and the orthographic projection of each of the second regions on the first backlight surface completely coincides with the orthographic projection of a third region on the first backlight surface.

3. The backlight module according to claim 1, characterized in that, The first light guide dot structure includes a plurality of first dots arranged in an array. Along the direction away from the first light incident surface, the density of the first dots in at least a portion of the first light guide dot structure gradually increases. The second light guide dot structure includes a plurality of second dots arranged in an array. Along the direction away from the second light incident surface, the density of the second dots in at least a portion of the second light guide dot structure gradually increases.

4. The backlight module according to claim 3, characterized in that, The density of the first dot in the first light guide dot structure is 20% to 60%; The density of the second dot in the second light guide dot structure is 20% to 60%.

5. The backlight module according to any one of claims 1 to 4, characterized in that, The first light-incident surface includes a plurality of first light-incident regions arranged at intervals along the first direction, and the orthographic projection of each first light-incident region onto the first light-emitting surface is located in one of the first light-incident regions. The first light source includes a plurality of first light-emitting structures arranged at intervals along the first direction, and each first light-emitting structure is located in one of the first light-incident regions. The second light-incident surface includes a plurality of second light-incident regions arranged at intervals along the first direction, and the orthographic projection of each second light-incident region onto the second light-emitting surface is located in one of the third regions. The second light source includes a plurality of second light-emitting structures arranged at intervals along the first direction, and each second light-emitting structure is located in one of the second light-incident regions.

6. The backlight module according to claim 5, characterized in that, The first light-emitting structure includes a plurality of first light-emitting units arranged at intervals along the first direction, and the plurality of first light-emitting units in the same first light-emitting structure are used to emit light or turn off simultaneously; The second light-emitting structure includes a plurality of second light-emitting units arranged at intervals along the first direction, wherein the plurality of second light-emitting units in the same second light-emitting structure are used to emit light or turn off simultaneously.

7. The backlight module according to claim 6, characterized in that, The backlight module includes two first light sources and two second light sources. The first light guide plate has two opposite first light incident surfaces, and the two first light sources are respectively located on one side of the two first light incident surfaces; The second light guide plate has two opposite second light incident surfaces, and the two second light sources are respectively located on one side of the two second light incident surfaces.

8. The backlight module according to claim 7, characterized in that, The backlight module further includes a light-shielding structure, which is located at least between the first light source and the second light guide plate, and between the second light source and the first light guide plate.

9. The backlight module according to any one of claims 1 to 4 and claims 6 to 8, characterized in that, The first light-emitting surface includes a plurality of first strip-shaped protrusions arranged sequentially and connected along the first direction, the first strip-shaped protrusions extending along a second direction, the second direction being perpendicular to the first direction; The second light-emitting surface includes a plurality of second strip-shaped protrusions arranged sequentially and connected along the first direction, the second strip-shaped protrusions extending along the second direction.

10. The backlight module according to claim 9, characterized in that, On a cross section perpendicular to the second direction, the cross-sectional shape of the first strip protrusion is arc-shaped, semi-circular, or triangular; The cross-sectional shape of the second strip-shaped protrusion is arc-shaped, semi-circular, or triangular.

11. The backlight module according to claim 9, characterized in that, In a direction perpendicular to both the first and second directions, the maximum height of the first strip protrusion is 25 μm to 35 μm. The maximum height of the second strip protrusion is 25 μm to 35 μm.

12. The backlight module according to claim 9, characterized in that, In the first direction, the distance between the center lines of two adjacent first strip protrusions is 140 μm to 160 μm; The distance between the center lines of two adjacent second strip protrusions is 140 μm to 160 μm.

13. The backlight module according to any one of claims 1 to 4, 6 to 8, and 10 to 12, characterized in that, The backlight module also includes a reflective sheet located on the first backlight surface.

14. The backlight module according to any one of claims 1 to 4, 6 to 8, and 10 to 12, characterized in that, In a direction perpendicular to the first backlight surface in the second region, the thickness of the first light guide plate is 1.4 mm to 1.6 mm; The thickness of the second light guide plate is 1.4 mm to 1.6 mm.

15. A display device, characterized in that, It includes a backlight module and a liquid crystal display panel as described in any one of claims 1 to 14, wherein the liquid crystal display panel is located on the light-emitting side of the backlight module.

Images