Backlight module and display apparatus

Abstract

Provided in the present invention is a backlight module, comprising a diffusion plate, and a light-emitting assembly located on a light-incident side of the diffusion plate, wherein the light-emitting assembly comprises a plurality of light-emitting bodies that are arranged in an array; the diffusion plate comprises an intermediate region, and an edge region arranged around the intermediate region, the width of the edge region perpendicular to an edge direction thereof is c, the minimum distance between the orthographic projection, on the diffusion plate, of a light-emitting body on the outermost edge in the light-emitting assembly and the edge of the diffusion plate is a, the distance between adjacent light-emitting assemblies is b, and c=a+b; and an ink layer is provided on the surface of the diffusion plate that faces away from the light-emitting assembly. The unit ink amount of an ink layer in an intermediate region is greater than the unit ink amount of the ink layer in an edge region, such that the transmittance of the intermediate region of a diffusion plate is less than the transmittance of the edge region, thereby reducing the brightness difference between the intermediate region and the edge region of the diffusion plate and improving the uniformity of brightness on the diffusion plate, and thus improving the backlight effect of a backlight module. Further provided in the present invention is a display apparatus.

Description

Backlight module and display device Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a backlight module and a display device. Background Art

[0002] Liquid crystal displays (LCDs) are developing at an increasingly rapid pace. Generally speaking, an LCD comprises a liquid crystal display panel and a backlight module. The liquid crystal display panel is composed of a thin film transistor substrate, a color filter substrate, and a liquid crystal layer disposed between these two substrates. The backlight module is used to provide the light source required by the liquid crystal display panel to enable the liquid crystal display device to achieve the desired display effect.

[0003] The working principle of the liquid crystal display panel is to place liquid crystal molecules between two parallel glass substrates. There are many vertical and horizontal thin wires between the two glass substrates. The direction of the liquid crystal analysis is controlled by whether the power is turned on or not, and the light from the backlight module is refracted to produce the picture.

[0004] Backlight modules are categorized into two types, edge-lit and direct-lit, depending on the location of the light source. In edge-lit backlight modules, the backlight LED strip is located at the edge of the back panel behind the LCD panel. Light from the LED strip enters the diffuser panel from the incident surface on one side, and after reflection and diffusion, it is emitted from the diffuser panel's light-emitting surface. It then passes through the optical film assembly to form a surface light source and is provided to the LCD panel. In direct-lit backlight modules, the light source is located behind the LCD panel, directly providing a surface light source to the LCD panel. The diffuser panel is a key component of the entire direct-lit backlight module.

[0005] With the development of LCDs, the demand for narrow-border modules has gradually increased, giving rise to LCD splicing screens. Due to the need for splicing, the demand for splicing screen borders has become increasingly narrow, and the image quality requirements on both sides of the seam have also become increasingly higher. Currently, the narrowest is the RNB splicing screen. Because the border is less than 1mm, the surrounding design space is limited, and the space for direct-lit backlights is restricted, the brightness on both sides of the seam is low, resulting in dark areas (also known as shadow areas) on both sides of the seam. The presence of dark areas affects the display quality of the display device.

[0006] Summary of the Invention

[0007] The present invention aims to solve at least one of the technical problems existing in the prior art, and proposes a backlight module and a display device.

[0008] To achieve the above-mentioned purpose, an embodiment of the present disclosure provides a backlight module, including a diffuser plate and a light-emitting component located on the light-incident side of the diffuser plate, the light-emitting component including a plurality of light-emitting bodies arranged in an array; the diffuser plate includes a middle area and an edge area arranged around the middle area, the width of the edge area perpendicular to its edge direction is c, the minimum distance between the orthographic projection of the light-emitting body at the edge of the light-emitting component on the diffuser plate and the edge of the diffuser plate is a, and the spacing between adjacent light-emitting components is b, where c=a+b; wherein an ink layer is provided on the surface of the diffuser plate facing away from the light-emitting component, and the unit ink amount of the ink layer in the middle area is greater than the unit ink amount of the ink layer in the edge area.

[0009] In some embodiments, the edge area includes multiple first areas and multiple second areas, at least one side of the first area is adjacent to the middle area; the unit ink volume of the ink layer in the first area is greater than or equal to the unit ink volume of the ink layer in the second area.

[0010] In some embodiments, the unit ink volume of the ink layer in the middle region is the same everywhere, and the unit ink volume of the ink layer in the second region is the same everywhere; the unit ink volume of the ink layer in the middle region is twice the unit ink volume of the ink layer in the second region.

[0011] In some embodiments, the unit ink usage of the ink layer in the first region gradually increases from the edge of the diffusion plate toward the middle region.

[0012] In some embodiments, the unit ink usage of the ink layer in the first region satisfies the following formula: y=0.35x2-2.15x+51.75, where x is the distance from the edge of the diffuser plate, and y is the unit ink usage.

[0013] In some embodiments, the light-emitting component includes a plurality of light-emitting bodies, which are used to emit light toward the diffusion plate after being powered on; the plurality of light-emitting bodies include a first light-emitting group corresponding to the middle area and a second light-emitting group corresponding to the edge area, and the current intensity of the second light-emitting group is greater than the current intensity of the first light-emitting group.

[0014] In some embodiments, the edge region includes multiple first regions and multiple second regions, and at least one side of the first region is adjacent to the middle region; the second light-emitting group includes a first subgroup corresponding to the first region and a second subgroup corresponding to the second region, and the current intensity of the first subgroup is less than the current intensity of the second subgroup.

[0015] In some embodiments, the middle area includes a third area and a fourth area surrounding the third area; the first light-emitting group includes a third subgroup corresponding to the third area and a fourth subgroup corresponding to the fourth area, and the current intensity of the third subgroup is less than the current intensity of the fourth subgroup.

[0016] In some embodiments, the ratio of the current intensity of the third subgroup, the current intensity of the fourth subgroup, the current intensity of the first subgroup, and the current intensity of the second subgroup is 52:65:75:80.

[0017] In some embodiments, the backlight module further includes: a reflector disposed on the outside of the diffuser plate, the reflector being used to collect light emitted by the light-emitting component that does not enter the diffuser plate, and reflect the collected light to the edge area to increase the brightness of the edge area.

[0018] In some embodiments, the reflectivity of the reflective element is 80% to 95%.

[0019] In some embodiments, the thickness of the diffuser plate is greater than or equal to 1.1 mm and less than or equal to 3 mm.

[0020] An embodiment of the present disclosure further provides a display device, comprising a display panel and the backlight module as described above, wherein the display panel is disposed on the other side of the diffusion plate away from the light-emitting component.

[0021] In some embodiments, the display panel includes a pixel array, the pixel array includes a plurality of pixels; the plurality of pixels are arranged into a plurality of pixel rows along a first direction, and a plurality of pixel columns along a second direction; wherein the first direction intersects with the second direction; the aperture ratio of all pixels in the pixel row gradually decreases from the first edge of the pixel array toward the direction close to the middle area; the first edge of the pixel array is parallel to the first direction; the aperture ratio of all pixels in the pixel column gradually decreases from the second edge of the pixel array toward the direction close to the middle area; the second edge of the pixel array is parallel to the second direction.

[0022] In some embodiments, the aperture ratio of a pixel satisfies the following formula: m=-0.027㏑(n)+0.6994; wherein m is the aperture ratio of the pixel, and n is the number of pixels from the pixel to the corresponding edge.

[0023] In some embodiments, the display panel includes an array substrate and a matching substrate arranged in a box with the array substrate, and a liquid crystal layer is provided between the array substrate and the matching substrate; the matching substrate includes a first substrate and a shading structure located on the first substrate; the width of the shading structure in the middle area is greater than the width of the shading structure in the edge area.

[0024] In some embodiments, the width of the light shielding structure is greater than or equal to 117 μm and less than or equal to 139.4 μm.

[0025] In some embodiments, the display panel includes an array substrate and a matching substrate arranged in a box with the array substrate, and a liquid crystal layer is provided between the array substrate and the matching substrate; the array substrate includes a second substrate and a scan line layer located on the second substrate; the width of the scan line layer in the middle area is greater than the width of the scan line layer in the edge area.

[0026] In some embodiments, the width of the scan line layer is greater than or equal to 60 μm and less than or equal to 80 μm.

[0027] In some embodiments, the array substrate further includes a common electrode line layer on the second substrate, and the distance between the orthographic projections of the common electrode line layer and the scanning line layer on the second substrate in the middle area is greater than the distance between the orthographic projections of the common electrode line layer and the scanning line layer on the second substrate in the edge area.

[0028] In some embodiments, the array substrate further includes a first electrode and a second electrode located on the second substrate, the second electrode being located on the side of the first electrode facing away from the second substrate; the spacing between the first electrode and the orthographic projection of the scanning line layer on the second substrate in the middle region is equal to the spacing between the first electrode and the orthographic projection of the scanning line layer on the second substrate in the edge region; the spacing between the second electrode and the orthographic projection of the scanning line layer on the second substrate in the middle region is equal to the spacing between the second electrode and the orthographic projection of the scanning line layer on the second substrate in the edge region. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] FIG. 1 is a schematic diagram showing the brightness at various locations on a diffusion plate in the related art.

[0030] FIG. 2 is a schematic diagram showing the relative positions of a diffusion plate and a light-emitting component of a backlight module according to an embodiment of the present invention.

[0031] FIG3 is a top view showing the relative positional relationship between the middle region and the edge region of a diffuser plate according to an embodiment of the present invention.

[0032] FIG4 is a top view showing the relative positional relationship between the middle region and the edge region of a diffuser plate according to another embodiment of the present invention.

[0033] FIG. 5 is a schematic diagram showing brightness at various locations on a diffusion plate according to an embodiment of the present invention.

[0034] FIG. 6 is a schematic diagram of a diffusion path of part of light in a diffusion plate of a backlight module in the related art.

[0035] FIG. 7 is a schematic diagram of a diffusion path of part of light in a diffusion plate of a backlight module according to an embodiment of the present invention.

[0036] FIG. 8 is a schematic diagram of a display panel of a display device according to an embodiment of the present invention.

[0037] FIG. 9 is a schematic diagram showing brightness at various locations on a display panel according to an embodiment of the present invention.

[0038] FIG10 is a schematic structural diagram of a display panel in a middle area according to an embodiment of the present invention.

[0039] FIG. 11 is a schematic structural diagram of an edge region of a display panel according to an embodiment of the present invention.

[0040] Explanation of symbols: 200, backlight module; 210, diffusion plate; 211, middle area; 211a, third area; 211b, fourth area; 212, edge area; 212a, first area; 212b, second area; 220, light-emitting component; 221, light-emitting body; 311, first substrate; 312, shading structure; 321, second substrate; 322, scanning line layer; 323, common electrode line layer; 324, first electrode; 325, second electrode. DETAILED DESCRIPTION

[0041] To make the objectives, technical solutions, and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0042] The shapes and sizes of the components in the drawings do not reflect the actual proportions, and are only intended to facilitate understanding of the contents of the embodiments of the present invention.

[0043] Unless otherwise defined, the technical or scientific terms used in this disclosure should have the usual meanings understood by people with ordinary skills in the field to which this disclosure belongs. The words "first", "second" and similar words used in this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one", "an" or "the" do not indicate a quantity limitation, but rather indicate the existence of at least one. Words such as "include" or "comprise" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0044] The embodiments of the present disclosure are not limited to the embodiments shown in the drawings, but include modifications of the configurations formed based on the manufacturing process. Therefore, the regions illustrated in the drawings are schematic in nature, and the shapes of the regions shown in the drawings illustrate the specific shapes of the regions of the elements, but are not intended to be limiting.

[0045] The backlight module 200 includes a diffuser plate 210 and a light-emitting assembly 220. The light-emitting assembly 220 may include a plurality of light-emitting elements 221 arranged in an array, wherein each light-emitting element 221 may be an LED. The light-emitting assembly 220 is located on the light-incident side of the diffuser plate 210. Light emitted by the light-emitting assembly 220 passes through the diffuser plate 210 and is refracted within the diffuser plate 210. Due to the positional limitations of the light-emitting assembly 220, the brightness at the edges of the diffuser plate 210 is lower than that at the center. This means that the overall brightness of the diffuser plate 210 is uneven, with a significant difference in brightness. The darker areas at the edges of the diffuser plate 210 can be referred to as "shadow areas." Because the sizes of display devices vary across different fields, the sizes of shadow areas also vary. For ease of explanation, this embodiment uses an eye-sensing light field display (ELFD) spliced ​​screen as an example. The display device described below is a display unit of the spliced ​​screen.

[0046] FIG1 is a schematic diagram of the brightness at various locations on the diffusion plate of the related art. Referring to FIG1 , the horizontal axis represents the distance from the edge of the diffusion plate 210, and the vertical axis represents the brightness. It can be understood that the larger the value in the vertical axis, the brighter the brightness. The inventors of the present disclosure have found through testing that the brightness on the diffusion plate 210 starts to decrease from a position 20 mm away from the edge, and drops rapidly at a position 10 mm away from the edge. That is, there is a large difference between the brightness of the normal brightness area and the brightness of the shadow area on the diffusion plate 210, resulting in the shadow area being darker than the normal brightness area. This is reflected in the spliced ​​screen of the eye-sensing light field display, that is, the splicing seam is larger (there is a shadow area on the diffusion plate 210 of a single display unit), which affects the final display effect. Through the above test, it can be known that the width of the shadow area is generally 0 to 20 mm.

[0047] In order to solve the above technical problems, the present application proposes a backlight module 200, which can reduce the brightness difference between the middle area 211 and the edge area 212 of the diffuser 210, improve the uniformity of the brightness on the diffuser 210, and thus improve the final display effect.

[0048] FIG2 is a schematic diagram of the relative positions of the diffuser plate 210 and the light-emitting component 220 of the backlight module 200 according to an embodiment of the present invention. Referring to FIG2 , a backlight module 200 according to a design scheme is shown. As shown in FIG2 , the diffuser plate 210 in the present disclosure may include a middle area 211 and an edge area 212, and the edge area 212 is arranged around the middle area 211. At this time, the edge area 212 is the above-mentioned dark shadow area. For a display screen unit of an eye-sensing light field display, the width of the edge area 212 perpendicular to its edge direction is c, the minimum distance between the orthographic projection of the light-emitting body 221 at the edge of the light-emitting component 220 on the diffuser plate 210 and the edge of the diffuser plate 210 is a, and the spacing between adjacent light-emitting components 220 is b, where c=a+b. For details, please refer to FIG1 .

[0049] Example 1

[0050] Specifically, an ink layer is provided on the surface of the diffusion plate 210 facing away from the light emitting assembly 220 in this embodiment, and the unit ink volume of the ink layer in the middle region 211 is greater than the unit ink volume of the ink layer in the edge region 212 .

[0051] This embodiment achieves non-uniform ink printing across the entire diffuser plate 210 by setting the unit ink volume of the ink layer in the middle region 211 to be greater than the unit ink volume of the ink layer in the edge region 212. This reduces the unit ink volume in the edge region 212 of the diffuser plate 210, thereby increasing the transmittance of the edge region 212 of the diffuser plate 210 and thereby improving the brightness of the edge region 212 of the diffuser plate 210. It will be appreciated that this embodiment defines the edge region 212 as a dark shadow region, and therefore, this embodiment can improve the brightness of the dark shadow region, thereby resolving the aforementioned technical problem.

[0052] FIG3 is a top view illustrating the relative positional relationship between the middle region 211 and the edge region 212 of a diffuser plate 210 according to one embodiment of the present invention. Referring to FIG3 , the edge region 212 of this embodiment is disposed around the middle region 211. The edge region 212 includes a plurality of first regions 212a and a plurality of second regions 212b, with at least one side of the first region 212a being adjacent to the middle region 211. In some embodiments, the edge region 212 includes four first regions 212a and four second regions 212b, with the second regions 212b being located at the four corners of the edge region 212. For details, please refer to FIG3 .

[0053] Since the brightness of the first region 212a and the second region 212b in the edge region 212 is also different, the brightness of the second region 212b is lower than that of the first region 212a. Therefore, the unit ink volume of the ink layer in the first region 212a is greater than or equal to the unit ink volume of the ink layer in the second region 212b, resulting in a lower transmittance of the first region 212a than that of the second region 212b, thereby reducing the difference in brightness between the first region 212a and the second region 212b in the edge region.

[0054] In this embodiment, the unit ink volume of the ink layer in the middle area 211 is the same everywhere, and the unit ink volume of the ink layer in the second area 212b is the same everywhere, and the unit ink volume of the ink layer in the middle area 211 is greater than the unit ink volume of the ink layer in the second area 212b, so that the transmittance of the middle area 211 is less than the transmittance of the second area 212b. For example, the transmittance of the middle area 211 can be 75%, and the transmittance of the second area 212b can be 80%.

[0055] In some embodiments, the unit ink volume of the ink layer in the middle region 211 is twice the unit ink volume of the ink layer in the second region 212b.

[0056] The unit ink amount of the ink layer in the first area 212 a may be set to change gradually. For example, the unit ink amount of the ink layer in the first area 212 a may gradually increase from the edge of the diffusion plate 210 toward the middle area 211 .

[0057] The unit ink usage of the ink layer in the first area 212 a satisfies the following formula: y=0.35x 2 -2.15x+51.75, where x is the distance from the edge of the diffusion plate 210 and y is the unit ink usage.

[0058] Within the first region 212a, the relationship between ink ratio and transmittance is as follows: u = 0.1v + 0.7, where u represents transmittance and v represents ink ratio. The ink ratio can be understood as the ratio of the unit ink volume to the unit ink volume in the middle region 211. For example, if the ink volume in the second region 212b is 50 and the ink volume in the middle region 211 is 100, then the ink ratio in the second region 212b is 50:100, or 0.5. In this embodiment, the ink ratio in the first region 212a is related to the distance from the edge of the diffuser plate 210. The relationship between the ink ratio and the distance from the edge of the diffuser plate 210 is as follows: p = 0.0004q² - 0.0022q + 0.7518, where q is the distance from the edge of the diffuser plate 210 and p is the ink ratio.

[0059] Experimental verification has shown that this embodiment significantly improves the brightness of the diffuser plate 210 at a distance of 15 to 20 mm from the edge, and also moderately improves the brightness of the diffuser plate 210 at a distance of 0 to 5 mm from the edge. The edge region 212 is 0 to 20 mm from the edge, meaning that this embodiment effectively improves the brightness of the edge region 212 and reduces the difference in brightness between the middle region 211 and the edge region 212. It is understood that to further improve the brightness of the diffuser plate 210 at a distance of 0 to 5 mm from the edge, the current of the light emitter 221 at a distance of 0 to 5 mm from the edge can be increased according to actual conditions.

[0060] Figure 4 is a top view of the relative positions of the central region 211 and edge regions 212 of a diffuser plate 210 according to another embodiment of the present invention. Referring to Figure 4 , the central region 211 can be further divided into a third region 211a and a fourth region 211b, with the unit ink volume of the ink layer in the third region 211a being greater than the unit ink volume of the ink layer in the fourth region 211b. By subdividing the diffuser plate 210 in this embodiment, the transmittance of each region on the diffuser plate 210 can be better controlled, improving brightness uniformity across the diffuser plate 210.

[0061] Example 2

[0062] The light-emitting component 220 includes multiple light-emitting bodies 221, which are used to emit light toward the diffuser 210 after being powered on. Each light-emitting body 221 can be an LED or other light-emitting device that can emit light. No specific limitation is made here. That is, the light-emitting component 220 includes multiple LEDs, and the light emitted by the light-emitting body 221 is refracted in the diffuser 210.

[0063] The plurality of light emitters 221 include a first light emitting group and a second light emitting group. The first light emitting group corresponds to the middle region 211 of the diffuser 210, and the second light emitting group corresponds to the edge region 212 of the diffuser 210. In some embodiments, the current intensity of the second light emitting group is greater than the current intensity of the first light emitting group.

[0064] In this embodiment, the current of the light emitting body 221 corresponding to the edge area 212 of the diffusion plate 210 is enhanced to reduce the difference in brightness between the middle area 211 and the edge area 212 .

[0065] The edge region 212 includes a plurality of first regions 212a and a plurality of second regions 212b, wherein at least one side of the first region 212a is adjacent to the middle region 211. In some embodiments, the edge region 212 includes four first regions 212a and four second regions 212b, wherein the second regions 212b are four regions located at the four corners of the edge region 212. For details, please refer to FIG. 3.

[0066] Since the brightness of the first region 212a and the second region 212b in the edge region 212 is different, the brightness of the second region 212b is lower than that of the first region 212a. In this embodiment, the second light-emitting group includes a first subgroup corresponding to the first region 212a and a second subgroup corresponding to the second region 212b. The current intensity of the first subgroup is lower than that of the second subgroup, thereby further subdividing the current intensity of the light-emitting elements 221 corresponding to different brightness regions in the edge region 212.

[0067] Furthermore, the middle region 211 includes a third region 211a and a fourth region 211b surrounding the third region 211a, as shown in Figure 4. The first light-emitting group includes a third subgroup corresponding to the third region 211a and a fourth subgroup corresponding to the fourth region 211b. The current intensity of the third subgroup is smaller than that of the fourth subgroup.

[0068] In some embodiments, the current intensity of the light-emitting assembly 220 can be set in a stepwise manner. For example, the ratio of the current intensity of the third subgroup, the current intensity of the fourth subgroup, the current intensity of the first subgroup, and the current intensity of the second subgroup is 65%:81.25%:93.75%:100%. In other words, the ratio of the current intensity of the third subgroup, the current intensity of the fourth subgroup, the current intensity of the first subgroup, and the current intensity of the second subgroup is 52:65:75:80.

[0069] Specifically, the size of each area in FIG4 can be set to the area of ​​the second area 212b as the area occupied by one partition, and the width of the first area 212a and the fourth area 211b can both be set to the width occupied by one partition. The above-mentioned one partition can be understood as two horizontal rows and three columns of LED lights, with a size of 6 pixels, or approximately 14*8.

[0070] FIG5 is a schematic diagram of the brightness at various locations on the diffuser plate 210 according to an embodiment of the present invention. Referring to FIG5 , the horizontal axis represents the distance from the edge of the diffuser plate 210, and the vertical axis represents the brightness. It can be understood that the larger the value in the vertical axis, the brighter it is. The inventors of the present disclosure have found through testing that when the ratio between the current intensity of the third subgroup, the current intensity of the fourth subgroup, the current intensity of the first subgroup, and the current intensity of the second subgroup is 52:65:75:80, the brightness on the diffuser plate 210 starts to decrease from a position 10 mm away from the edge, and drops rapidly at a position 5 mm away from the edge. Compared with the brightness change from the middle area 211 to the edge area 212 (0 to 20 mm) in the related art ( FIG2 ), the brightness difference between the portion of the edge area 212 close to the middle area 211 and the middle area 211 is smaller, thereby shortening the brightness difference between the middle area 211 and the edge area 212.

[0071] That is, experimental verification shows that this embodiment can significantly improve the brightness at a location 10 to 20 mm from the edge of the diffuser plate 210, and can also moderately improve the brightness at a location 0 to 10 mm from the edge of the diffuser plate 210. It is understood that if one wishes to further significantly improve the brightness at a location 0 to 10 mm from the edge of the diffuser plate 210, the current of the light-emitting element 221 at a location 0 to 10 mm from the edge of the diffuser plate 210 can be increased according to actual circumstances.

[0072] Example 3

[0073] The backlight module 200 further includes a reflector disposed outside the diffuser plate 210. The reflector collects light emitted by the light-emitting assembly 220 that does not enter the diffuser plate 210 and reflects the collected light toward the edge region 212 to increase the brightness of the edge region 212.

[0074] In this embodiment, the brightness of the edge region 212 is increased by adding a emitting element, thereby reducing the difference in brightness between the middle region 211 and the edge region 212 .

[0075] In some embodiments, the reflective member may be a diffuse reflective strip.

[0076] Preferably, the reflectivity of the reflector is 80% to 95%.

[0077] In some embodiments, the light-emitting surface of the reflective film is connected to the sidewall of the diffuser plate 210 via an adhesive. For example, the light-emitting surface of the reflective film can be tightly attached to the sidewall of the diffuser plate 210 at both ends using adhesive. For example, the reflective film can be fixed to the sidewall of the diffuser plate 210 using double-sided tape. The required peel force for tightly attaching the reflective film to the diffuser plate 210 is 12 to 35 N / 25 mm.

[0078] Example 4

[0079] It is understandable that the existence of the shadow area on the diffuser plate 210 is because the light emitting component 220 emits less light toward the edge of the diffuser plate 210, so the diffusion path of the light emitted by the light emitting component 220 in the diffuser plate 210 will affect the width of the shadow area.

[0080] FIG6 is a schematic diagram of the diffusion path of part of the light in the diffuser plate 210 of the backlight module 200 of the related art. Referring to FIG6 , the one-way arrow in the figure represents a beam of light emitted by the light-emitting component 220, wherein the exit point of the beam of light on the diffuser plate 210 is the junction of the edge area 212 and the middle area 211. After passing through two fold lines, the beam of light arrives at the side of the diffuser plate 210 away from the light-emitting component 220. The gray shaded area in FIG6 represents the darker area in the edge area 212. In addition, in FIG6 , H represents the thickness of the diffuser plate 210, L represents the width of the gray shaded area, W represents the distance from the incident point of the above-mentioned light beam to the edge area 212, θ is the incident angle of the above-mentioned light, and α is the refraction angle of the above-mentioned light.

[0081] In order to solve the above technical problems, this embodiment reduces the width of the darker area in the edge region 212 and improves the thickness of the diffusion plate 210 .

[0082] FIG7 is a schematic diagram illustrating the diffusion path of a portion of light within the diffuser plate 210 of the backlight module 200 according to one embodiment of the present invention. Referring to FIG7 , this embodiment increases the thickness of the diffuser plate 210 to improve the brightness of the upper edge region 212 of the diffuser plate 210. It should be noted that the diffuser plate 210 in FIG7 is only thicker than the diffuser plate 210 in FIG6 , meaning that the incident point of the light (the point where the light enters the diffuser plate 210 on the light-entering side) remains the same. It is understood that, given the same incident point, the increased thickness of the diffuser plate 210 increases the light's transmission path within the diffuser plate 210, changing the light's exit point (the point where the light exits the diffuser plate 210 on the other side of the diffuser plate 210). This increases W. Since the sum of (W + L) remains unchanged, L decreases, shortening the width of the darker region in the edge region 212.

[0083] In some embodiments, the thickness of the diffuser plate 210 is greater than or equal to 1.1 mm and less than or equal to 3 mm.

[0084] Generally speaking, the relationship between W and H mentioned above is as follows:

[0085] The normal incident angle θ is 70-80°, and the glass refractive index n is 1.5-1.7, so α is 33-41°.

[0086] When the thickness H of the diffuser plate 210 is 1.1 mm, W is approximately 0.6-0.72 mm, and the width L of the gray shaded area is approximately 4 mm.

[0087] When the thickness H of the diffusion plate 210 is 3 mm, W is approximately 1.6 to 2 mm, and the width L of the gray shaded area is approximately 2.72 to 3 mm.

[0088] It should be noted that the thickness of the diffusion plate 210 affects the brightness loss, and the two are in direct proportion. That is, an increase in the thickness of the diffusion plate 210 will increase the brightness loss.

[0089] Generally speaking, the relationship between transmittance and the thickness of the diffuser 210 is: -K(transmittance)=K*H, where K is a constant and H is the thickness of the diffuser 210. The K of the diffuser 210 is usually 46.

[0090] When the thickness H of the diffusion plate 210 is 1.1 mm, the transmittance is approximately 89%.

[0091] When the thickness H of the diffuser plate 210 is 3 mm, the transmittance is approximately 72%.

[0092] When the thickness H of the diffuser plate 210 is increased to 6.1-7.4 mm, the brightness of the entire edge region 212 can be made equal to that of the center region 211, completely resolving the shadow problem. However, the light efficiency is lower, with a transmittance of 46%-52%. Therefore, considering both the edge region 212 and light efficiency, the optimal thickness of the diffuser plate 210 is 1.1-3 mm.

[0093] Example 5

[0094] The display device includes a display panel and a backlight module 200 disposed on the back side of the display panel. The backlight module 200 is a direct-lit backlight module and includes a diffuser plate 210 opposite the back side of the display panel and a light-emitting assembly 220 located on the side of the diffuser plate 210 away from the display panel. That is, the display panel is disposed on the other side of the diffuser plate 210 away from the light-emitting assembly 220. The diffuser plate 210 and the light-emitting assembly 220 are spaced apart. It should be noted that the display device may further include a backplate for arranging the light-emitting assembly 220. The backplate is located on the side of the diffuser plate 210 away from the display panel. The backplate and the diffuser plate 210 are stacked and spaced apart. The light-emitting assembly 220 is arranged on the surface of the backplate adjacent to the diffuser plate 210. A diffuser plate 210 bracket may also be installed between the backplate and the diffuser plate 210. The specific structure of the diffuser plate 210 bracket has been disclosed in the art and will not be further described here.

[0095] Fig. 8 is a schematic diagram of a display panel of a display device according to an embodiment of the present invention. Referring to Fig. 8 , the display panel includes a pixel array, and the pixel array includes a plurality of pixels.

[0096] The plurality of pixels are arranged into a plurality of pixel rows along a first direction and a plurality of pixel columns along a second direction; wherein the first direction intersects with the second direction.

[0097] The aperture ratios of all pixels in the pixel row gradually decrease from the first edge of the pixel array toward the middle region 211 , wherein the first edge of the pixel array is parallel to the first direction.

[0098] The aperture ratios of all pixels in the pixel row gradually decrease from the second edge of the pixel array toward the middle region 211 , wherein the second edge of the pixel array is parallel to the second direction.

[0099] It is understandable that the display panel may be a display screen or a liquid crystal display screen.

[0100] FIG9 is a schematic diagram of the brightness of various positions of the display panel according to an embodiment of the present invention. Referring to FIG9 , the horizontal axis represents the distance from the edge of the diffuser plate 210, and the vertical axis represents the brightness. It can be understood that the larger the value in the vertical axis, the brighter it is. The inventors of the present disclosure have found through testing that the brightness on the diffuser plate 210 in this embodiment begins to decrease from a position of about 7 mm from the edge, and drops rapidly at a position of 2 mm from the edge. Compared with the brightness change from the middle area 211 to the edge area 212 (0 to 20 mm) in the related art ( FIG2 ), the portion of the edge area 212 close to the middle area 211 has a smaller difference in brightness than the middle area 211, thereby shortening the difference in brightness between the middle area 211 and the edge area 212.

[0101] In this embodiment, the pixel opening of the display panel is adjusted to gradually increase the pixel transmittance of the edge region 212 , thereby increasing the brightness of the edge region 212 and reducing the brightness difference between the middle region 211 and the edge region 212 .

[0102] The pixel aperture ratio conforms to the following formula:

[0103] m=-0.027㏑(n)+0.6994;

[0104] Wherein, m is the aperture ratio of the pixel, and n is the number of pixels from the pixel to the corresponding edge (wherein one pixel includes three sub-pixels).

[0105] For example, when n=1, m=70%; when n=2, m=68.3%; when n=3, m=66.7%; when n=4, m=66%; when n=5, m=65.5%; when n=6, m=65.2%; and when n=7, m=65%. It should be noted that the above formula for pixel aperture ratio is an approximation, so when the aforementioned distance values ​​are substituted into the formula, there will be some deviation, which is normal.

[0106] It should be noted that the aperture ratio of the pixel can be reduced by increasing the thickness of the black matrix layer corresponding to the pixel or the thickness of the scanning line layer 322 .

[0107] Figure 10 is a schematic structural diagram of a display panel in the middle region 211 according to an embodiment of the present invention. Figure 11 is a schematic structural diagram of a display panel in the edge region 212 according to an embodiment of the present invention. Referring to Figures 10 and 11, the display panel includes an array substrate and a cell-mounted substrate aligned with the array substrate, with a liquid crystal layer disposed between the array substrate and the cell-mounted substrate. The cell-mounted substrate includes a first substrate 311 and a light-shielding structure 312 located on the first substrate 311, wherein the light-shielding structure 312 may be a black matrix layer.

[0108] In some embodiments, the width of the shading structure 312 in the middle area 211 is greater than the width of the shading structure 312 in the edge area 212, so that the aperture ratio of the middle area 211 is smaller than the aperture ratio of the edge area 212, thereby improving the brightness of the edge area 212 and achieving the purpose of shortening the width of the edge area 212.

[0109] Specifically, the width of the light shielding structure 312 is greater than or equal to 117 μm and less than or equal to 139.4 μm.

[0110] 10 and 11 , the display panel includes an array substrate and a cell-aligned substrate aligned with the array substrate, with a liquid crystal layer disposed between the array substrate and the cell-aligned substrate. The array substrate includes a second substrate 321 and a scan line layer 322 located on the second substrate 321 .

[0111] In some embodiments, the width of the scanning line layer 322 in the middle area 211 is greater than the width of the scanning line layer 322 in the edge area 212, so that the aperture ratio of the middle area 211 is smaller than the aperture ratio of the edge area 212, so that the brightness of the edge area 212 is improved, thereby achieving the purpose of narrowing the brightness difference between the edge area 212 and the middle area 211.

[0112] Specifically, the width of the scan line layer 322 is greater than or equal to 60 μm and less than or equal to 80 μm.

[0113] The spacing between the orthographic projections of the common electrode line layer 323 and the scan line layer 322 on the second substrate 321 in the middle region 211 is greater than the spacing between the orthographic projections of the common electrode line layer 323 and the scan line layer 322 on the second substrate 321 in the edge region 212. Referring to Figures 10 and 11 , the array substrate further includes a common electrode line layer 323 located on the second substrate 321. The spacing between the orthographic projections of the common electrode line layer 323 and the scan line layer 322 on the second substrate 321 in the middle region 211 is represented as r1 in Figures 10 and 11 , and the spacing between the orthographic projections of the common electrode line layer 323 and the scan line layer 322 on the second substrate 321 in the edge region 212 is represented as r2 in Figures 10 and 11 , where r1>r2.

[0114] 10 and 11 , the array substrate further includes a first electrode 324 and a second electrode 325 located on the second substrate 321 . The second electrode 325 is located on a side of the first electrode 324 facing away from the second substrate 321 .

[0115] The distance between the orthographic projections of the first electrode 324 and the scan line layer 322 on the second substrate 321 in the middle region 211 is equal to the distance between the orthographic projections of the first electrode 324 and the scan line layer 322 on the second substrate 321 in the edge region 212 .

[0116] The distance between the first electrode 324 in the middle area 211 and the orthographic projection of the scanning line layer 322 on the second substrate 321 is represented as s1 in Figures 10 and 11, and the distance between the first electrode 324 in the edge area 212 and the orthographic projection of the scanning line layer 322 on the second substrate 321 is represented as s2 in Figures 10 and 11, then s1=s2.

[0117] The distance between the second electrode 325 and the orthographic projection of the scan line layer 322 on the second substrate 321 in the middle region 211 is equal to the distance between the second electrode 325 and the orthographic projection of the scan line layer 322 on the second substrate 321 in the edge region 212 .

[0118] The distance between the second electrode 325 in the middle area 211 and the positive projection of the scanning line layer 322 on the second substrate 321 is represented as t1 in Figures 10 and 11, and the distance between the second electrode 325 in the edge area 212 and the positive projection of the scanning line layer 322 on the second substrate 321 is represented as t2 in Figures 10 and 11, then t1=t2.

[0119] It will be understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present invention, and the present invention is not limited thereto. Those skilled in the art will appreciate that various modifications and improvements can be made without departing from the spirit and substance of the present invention, and such modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A backlight module, characterized in that: It includes a diffusion plate and a light-emitting component located on the light-incident side of the diffusion plate, wherein the light-emitting component includes a plurality of light-emitting bodies arranged in an array; The diffusion plate includes a middle area and an edge area surrounding the middle area, the width of the edge area perpendicular to the edge direction thereof is c, the minimum distance between the orthographic projection of the light-emitting body at the edge of the light-emitting assembly on the diffusion plate and the edge of the diffusion plate is a, and the spacing between adjacent light-emitting assemblies is b, wherein c=a+b; Wherein, an ink layer is arranged on a surface of the diffusion plate facing away from the light-emitting component, and a unit ink volume of the ink layer in the middle area is greater than a unit ink volume of the ink layer in the edge area.

2. The backlight module according to claim 1, characterized in that: The edge area includes a plurality of first areas and a plurality of second areas, and at least one side of the first area is adjacent to the middle area; The unit ink volume of the ink layer in the first area is greater than or equal to the unit ink volume of the ink layer in the second area.

3. The backlight module according to claim 2, characterized in that: The unit ink volume of the ink layer in the middle area is the same everywhere, and the unit ink volume of the ink layer in the second area is the same everywhere; The unit ink volume of the ink layer in the middle region is twice the unit ink volume of the ink layer in the second region.

4. The backlight module according to claim 2, characterized in that: The unit ink usage of the ink layer in the first area gradually increases from the edge of the diffusion plate toward the middle area.

5. The backlight module according to claim 2, characterized in that: The unit ink usage of the ink layer in the first area meets the following formula: y=0.35x2-2.15x+51.75, wherein x is the distance from the edge of the diffusion plate, and y is the unit ink usage.

6. The backlight module according to claim 1, characterized in that: The light-emitting assembly includes a plurality of light-emitting bodies, and the light-emitting bodies are used to emit light to the diffusion plate after being powered on; The plurality of light-emitting bodies include a first light-emitting group corresponding to the middle area and a second light-emitting group corresponding to the edge area, and the current intensity of the second light-emitting group is greater than the current intensity of the first light-emitting group.

7. The backlight module according to claim 6, characterized in that: The edge area includes a plurality of first areas and a plurality of second areas, and at least one side of the first area is adjacent to the middle area; The second light-emitting group includes a first subgroup corresponding to the first area and a second subgroup corresponding to the second area, and a current intensity of the first subgroup is smaller than a current intensity of the second subgroup.

8. The backlight module according to claim 7, characterized in that: The middle area includes a third area and a fourth area arranged around the third area; The first light-emitting group includes a third subgroup corresponding to the third area and a fourth subgroup corresponding to the fourth area, and a current intensity of the third subgroup is smaller than a current intensity of the fourth subgroup.

9. The backlight module according to claim 8, characterized in that: The ratio of the current intensity of the third subgroup, the current intensity of the fourth subgroup, the current intensity of the first subgroup and the current intensity of the second subgroup is 52:65:75:

80.

10. The backlight module according to claim 1, characterized in that: The backlight module also includes: A reflector is arranged on the outer side of the diffusion plate, and is used to collect the light emitted by the light-emitting component but not entering the interior of the diffusion plate, and reflect the collected light to the edge area to increase the brightness of the edge area.

11. The backlight module according to claim 10, characterized in that: The reflectivity of the reflector is 80% to 95%.

12. The backlight module according to claim 1, characterized in that: The thickness of the diffusion plate is greater than or equal to 1.1 mm and less than or equal to 3 mm.

13. A display device, characterized in that: It comprises a display panel and a backlight module as claimed in any one of claims 1 to 12, wherein the display panel is arranged on the other side of the diffusion plate away from the light-emitting component.

14. The display device according to claim 13, characterized in that: The display panel includes a pixel array, the pixel array includes a plurality of pixels; the plurality of pixels are arranged into a plurality of pixel rows along a first direction and a plurality of pixel columns along a second direction; wherein the first direction intersects the second direction; The aperture ratio of all pixels in the pixel row gradually decreases from the first edge of the pixel array toward the middle area; the first edge of the pixel array is parallel to the first direction; The aperture ratios of all pixels in the pixel column gradually decrease from the second edge of the pixel array toward the middle area; the second edge of the pixel array is parallel to the second direction.

15. The display device according to claim 14, characterized in that: The aperture ratio of the pixel meets the following formula: m=-0.027㏑(n)+0.6994; Among them, m is the aperture ratio of the pixel, and n is the number of pixels corresponding to the edge of the pixel distance.

16. The display device according to claim 13, characterized in that: The display panel comprises an array substrate and a cell-matching substrate arranged in a cell-matching manner with the array substrate, and a liquid crystal layer is arranged between the array substrate and the cell-matching substrate; The box-matching substrate comprises a first substrate and a light shielding structure located on the first substrate; The width of the light shielding structure in the middle area is greater than the width of the light shielding structure in the edge area.

17. The display device according to claim 16, characterized in that: The width of the light shielding structure is greater than or equal to 117 μm and less than or equal to 139.4 μm.

18. The display device according to claim 13, characterized in that: The display panel comprises an array substrate and a cell-matching substrate arranged in a cell-matching manner with the array substrate, and a liquid crystal layer is arranged between the array substrate and the cell-matching substrate; The array substrate comprises a second substrate and a scan line layer located on the second substrate; The width of the scan line layer in the middle area is greater than the width of the scan line layer in the edge area.

19. The display device according to claim 18, characterized in that The width of the scanning line layer is greater than or equal to 60 μm and less than or equal to 80 μm.

20. The display device according to claim 18, characterized in that The array substrate also includes a common electrode line layer located on the second substrate, and the spacing between the orthographic projections of the common electrode line layer and the scanning line layer on the second substrate in the middle area is greater than the spacing between the orthographic projections of the common electrode line layer and the scanning line layer on the second substrate in the edge area.

21. The display device according to claim 18, characterized in that The array substrate further comprises a first electrode and a second electrode located on the second substrate, wherein the second electrode is located on a side of the first electrode away from the second substrate; The distance between the first electrode and the orthographic projection of the scanning line layer on the second substrate in the middle region is equal to the distance between the first electrode and the orthographic projection of the scanning line layer on the second substrate in the edge region; The spacing between the second electrode and the orthographic projection of the scan line layer on the second substrate in the middle region is equal to the spacing between the second electrode and the orthographic projection of the scan line layer on the second substrate in the edge region.

Images