Backlight module, display module, spliced screen and display device

Abstract

The invention provides a backlight module, a display module, a spliced display screen and a display device, and the backlight module comprises a light guide plate which comprises a light emitting surface and a bottom surface; the optical film material is positioned on one side of the light guide plate away from the bottom surface; the middle frame comprises a frame body and a plurality of supporting ribs, the frame body surrounds the peripheral side of the light guide plate, the side, close to the optical film material, of the frame body is a supporting side in the direction from the bottom face to the light emitting face, and the supporting ribs are arranged on the supporting side and protrude relative to the surface of the supporting side; the plurality of supporting ribs are sequentially distributed at intervals along the peripheral side edge of the light guide plate; supporting surfaces are formed on the sides, deviating from the supporting sides, of the supporting ribs, and the edge of at least one of the light guide plate and the optical film material is supported by the supporting surfaces of the corresponding supporting ribs in a matched mode; at least part of the supporting ribs comprise supporting rib bodies and at least one reinforcing rib connected between the supporting rib bodies and the supporting side surfaces. According to the backlight module, the display module, the spliced display screen and the display device, the image quality can be improved.

Description

Technical Field

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

[0002] With the development of display technology, the requirements for the image quality of displays are increasing. In particular, for display products such as splicing screens with narrow bezels, the requirements for the image quality of the surrounding area are more stringent, so it is necessary to improve the image quality of the surrounding area of ​​the display module. Summary of the Invention

[0003] This disclosure provides a backlight module, a display module, a splicing screen, and a display device, which can improve the peripheral image quality of the display module.

[0004] The technical solutions provided in this disclosure are as follows:

[0005] In a first aspect, embodiments of this disclosure provide a backlight module, including:

[0006] A light guide plate includes a light-emitting surface and a bottom surface disposed opposite to the light-emitting surface;

[0007] An optical film material is located on the side of the light guide plate away from the bottom surface; and

[0008] The middle frame includes a frame body and multiple support ribs. The frame body surrounds the outer periphery of the light guide plate, and in a first direction from the bottom surface to the light emitting surface, the side of the frame body closer to the optical film is a support side. The support ribs are disposed on the support side and protrude from the surface of the support side.

[0009] Multiple support ribs are distributed sequentially and at intervals along the four sides of the light guide plate;

[0010] In the first direction, the side of the support rib facing away from the support side is formed as a support surface, and the edge of at least one of the light guide plate and the optical film is supported by the support surfaces of the corresponding plurality of support ribs; at least a portion of the support ribs include a support rib body and at least one reinforcing rib connecting the support rib body and the support side surface.

[0011] For example, the supporting rib body further includes two vertical side surfaces arranged opposite to each other in a second direction, the second direction being the edge extension direction of the light guide plate corresponding to the supporting rib; wherein, at least one reinforcing rib is connected between each vertical side surface and the surface of the supporting side.

[0012] For example, the orthographic projection of the reinforcing rib on the first projection plane is a triangle, and the first projection plane is perpendicular to the surface of the vertical side and the supporting side; the reinforcing rib includes a first surface, a second surface and a third surface, the orthographic projections of the first surface, the second surface and the third surface on the first projection plane together form the outline of the triangle, and the first surface is connected to the vertical side, the second surface is connected to the surface of the supporting side, and the third surface is an inclined surface that is inclined relative to the surface of the supporting side.

[0013] For example, the included angle α of the third surface being inclined relative to the surface of the supporting side ranges from 30 to 60°.

[0014] For example, the height of the supporting rib body protruding relative to the supporting side is a first height H1, and the height of the reinforcing rib protruding relative to the supporting side is a second height H2, wherein the first height H1 is greater than the second height H2.

[0015] For example, the first height H1 and the second height H2 satisfy the following relationship: (1 / 2)*H1≤H2≤(2 / 3)*H1.

[0016] For example, the support rib is made of transparent material, and the frame body is a white plastic frame.

[0017] For example, the support rib and the frame body are integrally formed.

[0018] For example, among the several support ribs located on the same side edge of the light guide plate, the distance d between two adjacent support ribs in the extending direction of that side edge is greater than or equal to 45 mm.

[0019] For example, the spacing d is greater than or equal to 60 mm and less than or equal to 100 mm.

[0020] For example, each of the four sides of the light guide plate corresponds to a plurality of the support ribs. The main body of the support rib has an extension length along a third direction, which is parallel to the light emitting surface and perpendicular to the edge of the light guide plate on the side corresponding to the support rib.

[0021] For example, when at least one of the four side edges of the light guide plate is a short edge, and the extension length of the short edge is less than a first threshold, the extension lengths of the plurality of support ribs corresponding to the short edge are all the same; and / or,

[0022] When at least one of the four sides of the light guide plate is a long edge, and the extension length of the long edge is greater than or equal to a first threshold, the plurality of support ribs corresponding to the long edge are configured such that the extension length of the support ribs distributed at the end position of the long edge is greater than or equal to the extension length of the support ribs distributed at the middle position of the long edge.

[0023] For example, the difference between the extension length of the support ribs distributed at the end of the long edge and the extension length of the support ribs distributed at the middle of the long edge is 0 to 5 mm.

[0024] For example, the long edge includes at least a first end region, a middle region and a second end region arranged sequentially along its own extension direction, and the extension lengths of the support ribs distributed in the first end region and the second end region are the same, and the extension lengths of the support ribs distributed in the middle region are the same.

[0025] For example, the length of the central region along the extension direction of the long edge accounts for 1 / 3 to 1 / 2 of the total length of the long edge extension.

[0026] For example, the first threshold is 500 mm.

[0027] For example, the edge region of the light-emitting surface of the light guide plate is constructed as an arc surface, and the arc surface smoothly transitions to the edge of the bottom surface.

[0028] Secondly, embodiments of this disclosure also provide a display module, which includes:

[0029] Display panel; and

[0030] The backlight module as described above, wherein the display panel is located on the side of the optical film away from the light guide plate.

[0031] Thirdly, embodiments of this disclosure also provide a splicing display screen, which includes the display modules as described above, with the edges of the plurality of display modules abutting each other.

[0032] Fourthly, embodiments of this disclosure also provide a display device, which includes the display module described above.

[0033] The beneficial effects of the embodiments disclosed herein are as follows:

[0034] In the above solution, the backlight module includes a light guide plate, an optical film, and a middle frame. The optical film is disposed on the side of the light guide plate away from the bottom surface. The middle frame includes a frame body and multiple support ribs. The frame body surrounds the outer periphery of the light guide plate. In a first direction from the bottom surface to the light-emitting surface, the side of the frame body closer to the optical film is a support side. The support ribs are disposed on the support side and protrude from the surface of the support side. The multiple support ribs are distributed sequentially and at intervals along the four sides of the light guide plate. In the first direction from the bottom surface to the light-emitting surface, the side of the support rib away from the support side forms a support surface. The support surfaces of the multiple support ribs cooperate to support the edge of the light guide plate and / or the optical film. At least some of the support ribs include a support rib body and at least one reinforcing rib connecting the support rib body and the support side surface.

[0035] Thus, by having the edges of at least one of the light guide plate and the optical film supported by a plurality of spaced-apart support ribs, the problem of shadows around the display module screen can be reduced compared to the method of supporting the light guide plate and / or the optical film by the entire top surface of the middle frame.

[0036] Furthermore, by designing the support rib to include a support rib body and reinforcing ribs, the reinforcing ribs can strengthen the support rib body, preventing the support rib structure from being too weak to reliably support the optical film or light guide plate, thereby improving module reliability and product quality. Attached Figure Description

[0037] Figure 1 This diagram shows a partial cross-sectional view of the backlight module provided in some embodiments of this disclosure at the location where the support rib is provided;

[0038] Figure 2 This is a partial structural cross-sectional view of the backlight module provided in some embodiments of this disclosure at the gap between two adjacent support ribs;

[0039] Figure 3 This shows a partial structural cross-sectional view of the splicing display screen provided in some embodiments of this disclosure;

[0040] Figure 4 This diagram illustrates the distribution of support ribs in a backlight module provided in some embodiments of this disclosure.

[0041] Figure 5 A schematic diagram showing the concave shape of the side panel of the back panel;

[0042] Figure 6 A three-dimensional structural schematic diagram of the support rib in a backlight module according to some embodiments of this disclosure;

[0043] Figure 7 This diagram illustrates a partial structural view of the edge position of the light guide plate in a backlight module according to some embodiments of the present disclosure. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0045] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an,” “a,” or “the,” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “including,” “comprising,” or “containing,” and similar terms mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. The terms “connected,” “linked,” or similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms “upper,” “lower,” “left,” and “right,” 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.

[0046] Before providing a detailed description of the embodiments of this disclosure, the related technologies are described below:

[0047] In related technologies, with the development of display technology, the requirements for the image quality of the display screen are increasing day by day. In particular, for display products such as splicing screens with narrow bezel designs, the requirements for the image quality of the surrounding area of ​​the product are more stringent. However, in related technologies, the surrounding image of narrow bezel display modules has phenomena such as shadows, which affect the image quality of the surrounding area. Therefore, it is necessary to improve the image quality of the surrounding area of ​​the display module.

[0048] The inventors of this disclosure have discovered that one of the reasons for the aforementioned problems is that the backlight module may include a light source, a light guide plate, an optical film, and a mid-frame. The mid-frame can be located on the outer periphery of the light guide plate, and the edge of the optical film can overlap the mid-frame. The main function of the optical film is to mix the light emitted by the light source, so that the light is emitted evenly, thereby improving the brightness uniformity of the display module. If the overlap area between the mid-frame and the optical film is large, it will cause shadows to appear around the edges of the screen.

[0049] To improve the peripheral image quality of the display module, embodiments of this disclosure provide a backlight module, a display module, a video wall, and a display device.

[0050] The backlight module provided in this disclosure is used to provide a light source for a display panel. Combined with... Figure 1 and Figure 2 As shown, the backlight module includes: a light guide plate 100, an optical film 200, and a middle frame 300. The light guide plate 100 includes a light-emitting surface 100A and a bottom surface 100B opposite to the light-emitting surface 100A. The optical film 200 is located on the side of the light guide plate 100 away from the bottom surface 100B. The middle frame 300 includes a frame body 310 and multiple support ribs 320. The frame body 310 surrounds the outer periphery of the light guide plate 100, and in the first direction Z from the bottom surface 100B to the light-emitting surface 100A, the side of the frame body 310 closer to the optical film 200 is a support side 310A. The support ribs 320 are disposed on the support side 310A and protrude relative to the surface of the support side 310A.

[0051] Multiple support ribs 320 are distributed sequentially at intervals along the four sides of the light guide plate 100;

[0052] In the first direction Z, the side of the support rib 320 facing away from the support side 310A is formed as a support surface 320A, and the edge of at least one of the light guide plate 100 and the optical film 200 is supported by the support surfaces 320A of the corresponding plurality of support ribs 320.

[0053] At least part of the support rib 320 includes a support rib body 321 and at least one reinforcing rib 322 connecting the support rib body 321 and the surface of the support side 310A.

[0054] In the above solution, by having the edges of at least one of the light guide plate 100 and the optical film 200 supported by a plurality of spaced-apart support ribs 320, the problem of shadows around the display module screen can be reduced compared to the method of supporting the light guide plate 100 and / or the optical film 200 by the entire top surface of the middle frame 300.

[0055] Furthermore, by designing the support rib 320 to include a support rib body 321 and a reinforcing rib 322, the reinforcing rib 322 can reinforce the support rib body 321, which can prevent the support rib 320 from having insufficient structural strength, thus preventing the optical film material 200 or the light guide plate 100 from failing to support it reliably, thereby improving module reliability and product quality.

[0056] It should be noted that in some embodiments, the support surfaces 320A of each support rib 320 are on the same plane; in other words, the protrusion height of each support rib 320 relative to the surface of the top support side 310A is consistent. This ensures that the edges of the light guide plate 100 and / or the optical film 200 are supported on the same plane, thereby ensuring that the optical components such as the light guide plate 100 and the optical film 200 remain flat.

[0057] In some exemplary embodiments, such as Figure 1 As shown, the edge of the light guide plate 100 overlaps the support surface 320A of the support rib 320, and the light guide plate 100 and the support surface 320A of the support rib 320 can be bonded and fixed together using adhesive 500. For example, the adhesive 500 can be any suitable structure, such as double-sided tape. In this way, by bonding and fixing the light guide plate 100 to the support rib 320, the reliability of the module can be improved.

[0058] In some exemplary embodiments, such as Figure 6 As shown, the supporting rib body 321 also includes two vertical side surfaces 3211 arranged opposite to each other in the second direction Y, where the second direction Y is the edge extension direction of the light guide plate 100 corresponding to the supporting rib 320; wherein, at least one reinforcing rib 322 is connected between each vertical side surface 3211 and the surface of the supporting side 310A.

[0059] In the above scheme, at least one reinforcing rib 322 is provided on each of the two opposite vertical sides 3211 of the support rib 320. The reinforcing ribs 322 on both sides can serve as two side wings of the support rib 320, which can further enhance the strength of the support rib 320.

[0060] For example, please see Figure 6 As shown, the two opposing vertical sides 3211 of the support rib 320 are a first vertical side 3211a and a second vertical side 3211b, respectively. A first side wing reinforcing rib 322a connects the first vertical side 3211a to the support side 310A surface of the frame body 310, and a second side wing reinforcing rib 322b connects the second vertical side 3211b to the support side 310A surface of the frame body 310. For example, the first side wing reinforcing rib 322a and the second side wing reinforcing rib 322b are symmetrically distributed on opposite sides of the support rib body 321.

[0061] It is understood that in other embodiments, the arrangement and number of the reinforcing ribs 322 are not limited to this. For example, each vertical side 3211 of the support rib 320 may also be connected to two or more of the reinforcing ribs 322.

[0062] In some exemplary embodiments, the reinforcing rib 322 has a triangular orthographic projection on a first projection plane, which is perpendicular to the surfaces of the vertical side 3211 and the supporting side 310A. For example, Figure 6 As shown, the reinforcing rib 322 is in the shape of a triangular prism. This design allows the reinforcing rib 322 to effectively strengthen the supporting rib body 321, and it has a simple structure. However, the specific construction of the reinforcing rib 322 is not limited to this.

[0063] In some exemplary embodiments, such as Figure 6 As shown, the reinforcing rib 322 includes a first surface 3221, a second surface 3222, and a third surface 3223. The orthographic projections of the first surface 3221, the second surface 3222, and the third surface 3223 onto the first projection plane form the outline of the triangle. The first surface 3221 is connected to the vertical side surface 3211, the second surface 3222 is connected to the surface of the supporting side 310A, and the third surface 3223 is an inclined surface relative to the surface of the supporting side 310A. For example, the included angle α of the third surface 3223 relative to the surface of the supporting side 310A ranges from 30° to 60°.

[0064] Using the above scheme, the reinforcing rib 322 is designed as a triangular prism with a triangular cross-section. The supporting rib 320 can be made of materials such as resin and manufactured through injection molding or other molding processes. If the included angle α of the third surface 3223 relative to the surface of the supporting side 310A is too small, it cannot effectively reinforce the supporting rib body 321, which may lead to the breakage of the supporting rib body 321. If the included angle α of the third surface 3223 relative to the surface of the supporting side 310A is too large, it will be limited by the molding process, which may result in unevenness of the supporting surface 320A of the supporting rib 320 after the reinforcing rib 322 is formed. When the included angle α of the third surface 3223 relative to the surface of the supporting side 310A is in the range of 30 to 60°, it can ensure the reinforcement effect on the supporting rib body 321 without causing unevenness of the supporting surface 320A of the supporting rib 320 after molding.

[0065] For example, the angle α of inclination of the third surface 3223 relative to the surface of the supporting side 310A is 45°. It is understood that the construction of the reinforcing rib 322 is not limited to this.

[0066] In some exemplary embodiments, such as Figure 6As shown, the height of the supporting rib body 321 protruding relative to the supporting side 310A is a first height H1, and the height of the reinforcing rib 322 protruding relative to the supporting side 310A is a second height H2. The first height H1 is greater than the second height H2. In other words, in the first direction Z, the reinforcing rib 322 is lower than the supporting rib body 321.

[0067] This ensures that the edge of the light guide plate 100 is supported only by the supporting rib body 321, and the reinforcing rib 322 will not contact the light guide plate 100, thereby avoiding the unevenness of the supporting surface 320A from affecting the optical effect of the light guide plate 100.

[0068] If the height of the reinforcing rib 322 protruding from the surface of the supporting side 310A is too large, there is a risk that the reinforcing rib 322 will come into contact with the light guide plate 100, which will affect the flatness of the light guide plate 100; if the height of the reinforcing rib 322 protruding from the surface of the supporting side 310A is too small, it will not be able to reinforce the supporting rib 320.

[0069] In some exemplary embodiments, the first height H1 and the second height H2 satisfy the following relationship: (1 / 2)*H1≤H2≤(2 / 3)*H1. This avoids the reinforcing rib 322 from contacting the light guide plate 100 while also ensuring reinforcement of the support rib 320 and preventing its breakage.

[0070] Furthermore, in some embodiments, the frame body 310 can be made of white plastic or aluminum alloy, which can reflect light inside the backlight module to improve light uniformity and light utilization. For example, the frame body 310 is made of white PC (polycarbonate) material. The frame body 310 can be formed using injection molding. However, it is not limited to this.

[0071] In some embodiments, the support rib 320 may be integrally formed with the frame body 310. The support rib 320 may be made of the same material as the frame body 310 or a different material. For example, when the support rib 320 and the frame body 310 are made of the same material, they can be integrally formed using a single-color injection molding process; when the support rib 320 and the frame body 310 are made of different materials, they can be integrally formed using a two-color injection molding process.

[0072] As shown in the figure, the support surface 320A of the support rib 320 is a plane. If the support rib 320 is made of the same white material as the frame body 310, the light inside the backlight module cannot directly enter the support surface 320A, which may result in a dark appearance on the screen of the display module, affecting the overall screen quality.

[0073] To address the aforementioned issues, in some exemplary embodiments of this disclosure, the support rib 320 may be made of a transparent material, such as transparent PC (polycarbonate) or any other suitable material. This further mitigates the shadow effect caused by the overlap between the support rib 320 and the light guide plate 100. In this case, the support rib 320 and the frame body 310 can be integrally molded using a two-color injection molding process.

[0074] It should be noted that the two-color injection molding process has lower structural strength compared to the single-color injection molding process. However, since the support rib 320 is constructed to include a support rib body 321 and at least one reinforcing rib 322, the problem of insufficient structural strength of the support rib 320 can be avoided by using the reinforcing rib 322 to strengthen the support rib 320. The above is only an example. In other embodiments, the support rib 320 and the frame body 310 can also be designed separately, with the two connected together.

[0075] A number of support ribs 320 are distributed along the edge of the light guide plate 100, and the spacing between adjacent support ribs 320 determines the number of support ribs 320 distributed on one side of the entire display module.

[0076] If there are too many support ribs 320, there will be more shadows around the screen, resulting in higher costs and a lower product yield when manufacturing the middle frame 300. If there are too few support ribs 320, the support for the light guide plate 100 will be insufficient, causing the collapse of the light guide plate 100 to exceed the threshold and affecting the uniformity of light.

[0077] In some embodiments of this disclosure, the spacing of the support ribs 320 has been optimized, such as... Figure 4 As shown, among the several support ribs 320 located on the same side edge of the light guide plate 100, the distance d between two adjacent support ribs 320 in the extending direction of that side edge is greater than or equal to 45 mm. In this case, the number of support ribs 320 will not be too large, and it can avoid affecting the sag of the optical film 200 or the light guide plate 100.

[0078] Table 1 shows the verification results of simulated calculations of the sag of the light guide plate 100 or the optical film 200 under different spacings of the supporting ribs 320. The thickness of the light guide plate 100 or the optical film 200 is 1.5 mm.

[0079] Table 1

[0080] Spacing d 40mm 60mm 80mm 100mm 125mm 150mm Maximum number of stays 0.583mm 0.676mm 0.772mm 1.041mm 1.247mm 1.556mm

[0081] As can be seen from the verification results in Table 1, when the spacing of the support ribs 320 varies between 40mm and 80mm, the sag of the light guide plate 100 or the optical film 200 increases by 0.189mm. The change in sag is small and has virtually no impact on the image quality.

[0082] Therefore, in order to minimize the number of support ribs 320, in some embodiments, the distance d between the extending directions of two adjacent support ribs 320 on this side edge is greater than or equal to 45 mm. For example, the distance d is greater than or equal to 60 mm and less than or equal to 100 mm.

[0083] In one specific embodiment, taking a 55-inch display module as an example, the pitch d can be 80mm, and the number of support ribs 320 on the long side of the display module can be 15, and the number of support ribs 320 on the short side can be 8. However, it is not limited to this.

[0084] In order to achieve effective overlap between the support rib 320 and the light guide plate 100, such as Figure 4 and Figure 6 As shown in some exemplary embodiments of this disclosure, each of the four sides of the light guide plate 100 corresponds to a plurality of the supporting ribs 320. The supporting rib body 321 has an extension length along a third direction X, which is parallel to the light emitting surface 100A and perpendicular to the edge of the light guide plate 100 on the side corresponding to the supporting rib 320. In other words, the supporting rib 320 needs to extend a certain distance along a direction from the edge of the light guide plate 100 to the center of the light guide plate 100. For example, the extension length can be 2 to 3 mm.

[0085] In some embodiments, the backlight module may further include a back plate 400, which includes a bottom plate portion 410 and a side plate portion 420. The bottom plate portion 410 is located on the side of the bottom surface 100B of the light guide plate 100 that faces away from the light emitting surface 100A. The side plate portion 420 is bent relative to the bottom plate portion 410 and located around the periphery of the middle frame 300. The back plate 400 can serve as a support structure for the entire backlight module. By combining with the middle frame 300, etc., it can fix the light source, the optical film 200, and the display panel, thereby achieving the structural stability of the entire display module.

[0086] The material of the back plate 400 can be SECC (electrolytic zinc-plated steel sheet), SGCC (hot-dip galvanized steel sheet), etc. In actual product production, the side plate portion 420 on the back plate 400 needs to be bent relative to the bottom plate portion 410. The side plate portion 420 includes four sub-side plates corresponding to the four sides of the light guide plate 100.

[0087] The four sub-side panels have pre-reserved gaps at their corner overlaps to avoid collisions during bending. Therefore, the bending angle at the corners of the sub-side panels is smaller than the bending angle at the center of the sub-side panels. Figure 5 As shown, in the back panel 400, each of the sub-side panels of the side panel portion 420 exhibits a concave shape in the middle compared to the ends. This results in an increased overlap area between the edge of the light guide plate 100 and the support rib 320 at the middle position, even exceeding the design value, thus affecting the image quality.

[0088] In particular, when at least one of the four sides of the light guide plate 100 is a long edge with an extension length greater than or equal to the first threshold, the surrounding image on the side corresponding to the long edge is more likely to be affected.

[0089] To improve the above problems, in some exemplary embodiments of this disclosure, as shown in the figure, when at least one side edge of the light guide plate 100 is a long edge 130, and the extension length of the long edge 130 is greater than or equal to a first threshold, the plurality of support ribs 320 corresponding to the long edge 130 are configured such that the extension length of the support ribs 320 distributed at the end position of the long edge 130 is greater than or equal to the extension length of the support ribs 320 distributed at the middle position of the long edge 130.

[0090] In the above scheme, the long edge 130 of the light guide plate 100 corresponds to the long side of the entire display module. In order to improve the picture quality problem caused by the large indentation in the middle of the long side compared with the end, the support ribs 320 distributed at different positions on one side of the display module are designed differently, so that the extension length of the support ribs 320 distributed in the middle of the side is greater than the extension length of the support ribs 320 at the end, so as to compensate for the difference in the amount of overlap between the support ribs 320 and the light guide plate 100 on one side, thereby improving the picture quality.

[0091] It should be noted that when at least one of the four side edges of the light guide plate 100 is a short edge 140, and the extension length of the short edge 140 is less than a first threshold, since the indentation of the middle of the sub-side plate of the back plate 400 on the side where the short edge 140 is located is within the allowable range, it has little impact on the image quality. Therefore, in some embodiments, the extension lengths of the plurality of support ribs 320 corresponding to the short edge 140 can all be the same. Of course, this is not a limitation; in other embodiments, the extension lengths of the various support ribs 320 distributed corresponding to the short edge 140 can also be designed differently.

[0092] For example, the first threshold is 500mm. In the display module, a single side length greater than 500mm can be considered a long side, and the extension length of the support ribs 320 distributed along the long side can be designed differently; in the display module, a single side length less than 500mm can be considered a short side, and the extension length of the support ribs 320 distributed along the short side can all be the same. It is understood that the specific value of the first threshold is not limited to this.

[0093] Furthermore, in some embodiments of this disclosure, for the plurality of support ribs 320 distributed on one side of the long edge 130, the difference between the extension length of the support ribs 320 distributed at the end position of the long edge 130 and the extension length of the support ribs 320 distributed at the middle position of the long edge 130 can be 0 to 5 mm (i.e., Figure 4 (The difference between L1 and L2). However, it is not limited to this.

[0094] Furthermore, in some embodiments of this disclosure, such as Figure 4 As shown, the long edge 130, along its extension direction, includes at least a first end region S1, a middle region S2, and a second end region S3 arranged sequentially. The supporting ribs 320 distributed in the first end region S1 and the second end region S3 have the same extension length, and the supporting ribs 320 distributed in the middle region S2 have the same extension length. This allows for the design of the supporting ribs 320 on one side of the long edge 130 into two different sizes, facilitating design and manufacturing processes.

[0095] It is understood, of course, that in other embodiments, the extension length of the support ribs 320 at each position distributed on one side of the long edge 130 is not limited to this. For example, the long edge 130 is divided into N regions along its own extension direction, where N can be greater than 3. That is, the N regions are not limited to the first end region S1, the middle region S2, and the second end region S3. In the N regions, the extension length of the support ribs 320 in the same region can be the same, and the extension length of the support ribs 320 in different regions can be different. The closer the position is to the end of the long edge 130, the longer the extension length of the support ribs 320. Alternatively, along the direction from one end of the long edge 130 to the other end, the extension length of the support ribs 320 first gradually increases and then gradually decreases.

[0096] In some exemplary embodiments, the length of the central region S2 along the extending direction of the long edge 130 accounts for 1 / 3 to 1 / 2 of the total length of the long edge 130. For example, the length of the central region S2 accounts for 1 / 3 of the total length of the long edge 130. The lengths of the first end region S1 and the second end region S3 each account for 1 / 3 of the total length of the long edge 130. This configuration can further effectively improve the poor image quality caused by the large indentation of the back panel 400 in the middle of one side, and facilitates the structural design and molding of the mid-frame 300. However, it is understood that this is not a limitation.

[0097] Table 2 shows the data obtained from detecting the concavity of the back plate 400 at seven locations along one long edge 130 of the light guide plate 100. The seven locations are spaced apart from one end of the long edge 130 to the other. The length of the long side (i.e., the side where the long edge 130 is located) in the display module is 680 ± 1 mm.

[0098] Table 2

[0099] Location point 1 2 3 4 5 6 7 Concave amount 0.21 -0.05 -0.68 -0.97 -0.91 -0.73 -0.08

[0100] As can be seen from Table 2, the difference in the indentation of the sub-side of the back plate 400 between the middle position and the end position of the long edge 130 is approximately 0.5 to 1 mm. Therefore, the difference between the extension length of the support rib 320 distributed at the end position of the long edge 130 and the extension length of the support rib 320 distributed at the middle position of the long edge 130 can be 0.5 to 1 mm.

[0101] For example, the extension length of the support rib 320 distributed at the end of the long edge 130 can be 3 mm, and the extension length of the support rib 320 distributed at the middle of the long edge 130 can be 2.5 mm.

[0102] The main function of the light guide plate 100 is to mix the light emitted from the light source, so that the light is emitted evenly and the brightness uniformity is improved. The optical film material 200 may include a diffusion film or a brightness enhancement film. The diffusion film has a similar function to the light guide plate 100, which is to achieve a light uniformity effect. The brightness enhancement film may include a prism film layer, a dual brightness enhancement film (DBEF), etc., and its main function is to achieve light convergence and improve the brightness of the display module.

[0103] Both the light guide plate 100 and the optical film 200 can be made of light-transmitting materials such as PS (polystyrene), PC (polycarbonate), or glass. When the light guide plate 100 or the optical film 200 is made of materials such as PS (polystyrene) or PC (polycarbonate), the size of the light guide plate 100 or the optical film 200 will change due to temperature during the use of the module. Therefore, a certain expansion space needs to be reserved at the edge of the light guide plate 100 or the optical film 200, which results in a noticeably dark dividing line at the edge of the image in the display module.

[0104] The inventors of this disclosure discovered through simulating the optical path that one of the reasons for the boundary line is that, due to the significant difference in light emission between the right-angled side edge of the light guide plate 100 and other positions, the light emitted from the right-angled side edge is more dispersed than that from other positions on the light-emitting surface 100A of the light guide plate 100. Most of the light will be emitted from the side of the light guide plate 100, thus less light is emitted towards the light-emitting surface 100A, resulting in a narrower dark line and causing a clear boundary line at the edge of the displayed image.

[0105] To address the aforementioned issues, this disclosure provides some exemplary embodiments, such as... Figure 7 As shown, the edge region of the light-emitting surface 100A is constructed as an arc surface P, and the arc surface P is smoothly connected to the edge of the bottom surface 100B.

[0106] In the above solution, by improving the right-angled side edge of the light guide plate 100 to a rounded curved surface P, the side light emission of the light guide plate 100 can be reduced, so that the light is emitted from the light emitting surface 100A as much as possible in the direction away from the bottom surface 100B, thereby improving the local light uniformity and eliminating the boundary line problem caused by the right-angled side edge.

[0107] To further improve the effect of shadows at the edges of the image, in some exemplary embodiments, such as Figure 1As shown, the optical film material 200 includes a prism film layer 210, and the prism film layer 210 includes at least two stacked prisms.

[0108] The prism film layer 210 is composed of at least two stacked prisms, which can improve the brightness of the display module, improve energy efficiency, and reduce product power consumption compared to a single prism.

[0109] For example, the prism film layer 210 is a double prism formed by stacking two prisms, and the interference fringes of the two prisms are perpendicular to each other to avoid generating moiré patterns.

[0110] The backlight module provided in this disclosure can be applied to video wall displays to improve the quality of the spliced ​​images. However, it is not limited thereto.

[0111] In addition, this disclosure also provides a display module, which includes a display panel 10 and a backlight module provided in this disclosure, wherein the display panel 10 is located on the side of the optical film 200 away from the light guide plate 100.

[0112] In addition, such as Figure 3 As shown, this disclosure also provides a splicing display screen, which includes the display modules provided in this disclosure, with the edges of multiple display modules abutting each other.

[0113] This disclosure also provides a display device, which includes the display module provided in this disclosure. Obviously, the display module, splicing display screen, and display device provided in this disclosure also have the technical effects brought about by the backlight module provided in this disclosure, and will not be described again here.

[0114] The display device provided in this disclosure may include any of the aforementioned backlight module embodiments or arrangements and combinations thereof. The display device is a product with image display capabilities, such as: a monitor, television, billboard, digital photo frame, laser printer with display capabilities, telephone, mobile phone, personal digital assistant (PDA), digital camera, portable camcorder, viewfinder, navigator, vehicle, large-area wall, home appliance, information query equipment (such as e-government, banking, hospital, power sector business query equipment, monitors, etc.).

[0115] The following points need to be explained:

[0116] (1) The accompanying drawings of the embodiments of this disclosure only involve the structures involved in the embodiments of this disclosure. Other structures can be referred to the general design.

[0117] (2) For clarity, the thickness of layers or regions is enlarged or reduced in the drawings used to describe embodiments of the present disclosure, i.e., these drawings are not drawn to actual scale. It will be understood that when an element such as a layer, film, region or substrate is referred to as being “above” or “below” another element, the element may be “directly” located “above” or “below” the other element or there may be intermediate elements.

[0118] (3) Where there is no conflict, the embodiments of this disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.

[0119] The above are merely specific embodiments of this disclosure, but the scope of protection of this disclosure is not limited thereto. The scope of protection of this disclosure shall be determined by the scope of the claims.

Claims

1. A backlight module, characterized in that, include: A light guide plate includes a light-emitting surface and a bottom surface disposed opposite to the light-emitting surface; An optical film is located on the side of the light guide plate away from the bottom surface; and The middle frame includes a frame body and multiple support ribs. The frame body surrounds the outer periphery of the light guide plate, and in a first direction from the bottom surface to the light emitting surface, the side of the frame body closer to the optical film is a support side. The support ribs are disposed on the support side and protrude from the surface of the support side. Multiple support ribs are distributed sequentially and at intervals along the four sides of the light guide plate; In the first direction, the side of the support rib facing away from the support side is formed as a support surface, and the edge of at least one of the light guide plate and the optical film is supported by the support surfaces of the corresponding plurality of support ribs; at least a portion of the support ribs include a support rib body and at least one reinforcing rib connecting the support rib body and the support side surface.

2. The backlight module according to claim 1, characterized in that, The supporting rib body also includes two vertical side surfaces arranged opposite each other in a second direction, the second direction being the edge extension direction of the light guide plate corresponding to the supporting rib; wherein, at least one reinforcing rib is connected between each vertical side surface and the surface of the supporting side.

3. The backlight module according to claim 2, characterized in that, The reinforcing rib has a triangular orthographic projection on the first projection plane, which is perpendicular to the vertical side surface and the surface of the supporting side. The reinforcing rib includes a first surface, a second surface, and a third surface. The orthographic projections of the first surface, the second surface, and the third surface on the first projection plane together form the outline of the triangle. The first surface is connected to the vertical side surface, the second surface is connected to the surface of the supporting side, and the third surface is an inclined surface that is inclined relative to the surface of the supporting side.

4. The backlight module according to claim 3, characterized in that, The included angle α of the third surface relative to the surface of the supporting side ranges from 30° to 60°.

5. The backlight module according to claim 1, characterized in that, The height of the supporting rib body protruding relative to the supporting side is a first height H1, and the height of the reinforcing rib protruding relative to the supporting side is a second height H2, wherein the first height H1 is greater than the second height H2.

6. The backlight module according to claim 5, characterized in that, The first height H1 and the second height H2 satisfy the following relationship: (1 / 2)*H1≤H2≤(2 / 3)*H1.

7. The backlight module according to claim 1, characterized in that, The support ribs are made of transparent material.

8. The backlight module according to claim 7, characterized in that, The supporting rib and the main frame are integrally formed.

9. The backlight module according to claim 1, characterized in that, Among the several support ribs located on the same side edge of the light guide plate, the distance d between two adjacent support ribs in the extending direction of that side edge is greater than or equal to 45 mm.

10. The backlight module according to claim 9, characterized in that, The spacing d is greater than or equal to 60 mm and less than or equal to 100 mm.

11. The backlight module according to claim 1, characterized in that, Each of the four sides of the light guide plate corresponds to a plurality of the support ribs. The main body of the support rib has an extension length along a third direction, which is parallel to the light emitting surface and perpendicular to the edge of the light guide plate on the side corresponding to the support rib.

12. The backlight module according to claim 11, characterized in that, When at least one of the four side edges of the light guide plate is a short edge, and the extension length of the short edge is less than a first threshold, the extension lengths of the plurality of support ribs corresponding to the short edge are all the same; and / or, When at least one of the four sides of the light guide plate is a long edge, and the extension length of the long edge is greater than or equal to a first threshold, the plurality of support ribs corresponding to the long edge are configured such that the extension length of the support ribs distributed at the end position of the long edge is greater than or equal to the extension length of the support ribs distributed at the middle position of the long edge.

13. The backlight module according to claim 12, characterized in that, The difference between the extension length of the support ribs located at the end of the long edge and the extension length of the support ribs located at the middle of the long edge is 0 to 5 mm.

14. The backlight module according to claim 12, characterized in that, The long edge includes at least a first end region, a middle region and a second end region arranged sequentially along its own extension direction. The extension lengths of the support ribs distributed in the first end region and the second end region are the same, and the extension lengths of the support ribs distributed in the middle region are the same.

15. The backlight module according to claim 14, characterized in that, The length of the central region along the extension direction of the long edge accounts for 1 / 3 to 1 / 2 of the total length of the long edge extension.

16. The backlight module according to claim 12, characterized in that, The first threshold is 500 mm.

17. The backlight module according to claim 1, characterized in that, The edge region of the light-emitting surface of the light guide plate is constructed as an arc surface, and the arc surface smoothly transitions to the edge of the bottom surface.

18. A display module, characterized in that, include: Display panel; and The backlight module as claimed in any one of claims 1 to 17, wherein the display panel is located on the side of the optical film away from the light guide plate.

19. A splicing display screen, characterized in that, Includes the display modules as described in claim 18, wherein the edges of the plurality of display modules abut against each other.

20. A display device, characterized in that, Includes the display module as described in claim 18.

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