Backlight module and display device

Abstract

The invention provides a backlight module and a display device. The backlight module comprises a light source substrate, a reflection cup cover, a diffusion film, a light splitting film and a packaging shell, and the light source substrate comprises a plurality of light-emitting elements arranged in an array; the reflection cup cover is located on the side, where the light-emitting elements are arranged, of the light source substrate. The reflection cup cover comprises a plurality of mutually connected reflection cups, an opening is formed in the center of each reflection cup, at least one light-emitting element is located in the opening, and reflection walls of the reflection cups are arranged around the light-emitting elements; the diffusion film is located on the side, away from the light source substrate, of the reflection cup cover, at least part of the reflection cup cover makes contact with the diffusion film, and the at least two stacked light splitting films are located on the side, away from the light source substrate, of the diffusion film. According to the arrangement, the distance between the diffusion film and the light-emitting element can be compressed, the thickness of the backlight module is reduced, meanwhile, the light splitting film is utilized, the lattice pattern phenomenon is eliminated, the distance between the side edge area of the packaging shell and the light source substrate can be further reduced, and a narrow frame of the backlight module is achieved.

Description

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] With the continuous development of liquid crystal display technology, liquid crystal display devices have been widely used in all aspects of life. Liquid crystal display devices include backlight modules and display panels. The backlight module provides light source for the display panel and is an indispensable part of the liquid crystal display device.

[0003] At present, when the backlight of the existing display module is a direct-down design, there are limitations in the film layer stacking and frame design in the display module. For example, how to achieve thinning of the display module, narrow frame, uniform display brightness, etc., are all problems that need to be solved urgently to improve the performance of the display module. Summary of the invention

[0004] Based on the above problems, the present invention provides a backlight module and a display device, which is provided with at least a part of the reflective cup cover in contact with the diffusion film, so as to compress the distance between the diffusion film and the light-emitting element, reduce the thickness of the backlight module, and at the same time increase the light-splitting film, eliminate the grid phenomenon, and reduce the distance between the side area of ​​the packaging shell and the light source substrate, which is conducive to realizing a narrow frame of the backlight module.

[0005] In a first aspect, an embodiment of the present invention provides a backlight module, comprising:

[0006] A light source substrate, comprising a plurality of light emitting elements arranged in an array;

[0007] A reflective cup cover, the reflective cup cover is located on a side of the light source substrate where the light-emitting element is arranged; the reflective cup cover comprises a plurality of reflective cups connected to each other, an opening is arranged at the center of the reflective cup, at least one light-emitting element is located in the opening, and a reflective wall of the reflective cup is arranged around the light-emitting element;

[0008] The diffusion film is located on a side of the reflective cup away from the light source substrate, and at least a portion of the reflective cup is in contact with the diffusion film.

[0009] At least two stacked beam splitting films, located on a side of the diffusion film away from the light source substrate;

[0010] The packaging shell, the light source substrate, the reflective cup cover, the diffusion film and the beam splitter film are all located in an area defined by the packaging shell.

[0011] Based on the same inventive concept, in a second aspect, an embodiment of the present invention provides a display device, comprising the backlight module described in the first aspect.

[0012] In the backlight module provided by the embodiment of the present invention, the diffusion film is directly arranged on the side of the reflective cup cover away from the light source substrate, and at least a part of the reflective cup cover is in contact with the diffusion film, thereby compressing the distance between the diffusion film and the light-emitting element, and at the same time increasing the light-splitting film to eliminate the grid phenomenon; thereby achieving thinning of the backlight module, and in addition, the diffusion film does not need to be placed on the side frame glue, thereby reducing the area of ​​the side area of ​​the packaging shell where the frame glue is set, and reducing the distance between the side area of ​​the packaging shell and the light source substrate, which is conducive to achieving a narrow frame of the backlight module. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a cross-sectional schematic diagram of a backlight module provided by the prior art;

[0014] Figure 2 is a top view schematic diagram of a backlight module provided by an embodiment of the present invention;

[0015] Figure 3 for Figure 2 A schematic cross-sectional view of a backlight module along the AA' direction;

[0016] Figure 4 for Figure 2 A schematic cross-sectional view of a backlight module along the AA' direction;

[0017] Figure 5 for Figure 2 A schematic cross-sectional view of a backlight module along the BB' direction;

[0018] Figure 6 for Figure 2 A schematic cross-sectional view of another backlight module along the BB' direction;

[0019] Figure 7 for Figure 2 A schematic cross-sectional view of another backlight module along the BB' direction;

[0020] Figure 8 for Figure 2 A schematic cross-sectional view of another backlight module along the BB' direction;

[0021] Fig. 9 for Figure 2 A schematic cross-sectional view of another backlight module along the BB' direction;

[0022] Fig.10 for Figure 2 A schematic cross-sectional view of another backlight module along the BB' direction;

[0023] Fig.11 for Figure 2 A schematic cross-sectional view of another backlight module along the BB' direction;

[0024] Fig.12 for Figure 2 A schematic cross-sectional view of another backlight module along the BB' direction;

[0025] Fig.13 for Figure 2 A schematic cross-sectional view of another backlight module along the BB' direction;

[0026] Fig.14 for Figure 2 A schematic cross-sectional view of another backlight module along the BB' direction;

[0027] Fig.15 for Figure 2 A schematic cross-sectional view of another backlight module along the BB' direction;

[0028] Fig.16 A schematic diagram of a display device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0029] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0030] Figure 1 is a cross-sectional schematic diagram of a backlight module provided by the prior art, referring to Figure 1 In the prior art, a direct-down display module is provided, in which a light source substrate 11, a reflective cup 12 and a diffusion film 13 are sequentially arranged in a packaging shell 10. A sealant 14 is usually arranged in the side wall area of ​​the packaging shell 10, and the diffusion film 13 is placed on the sealant 14 to keep it stable. In this way, in the horizontal direction, that is, Figure 1 In the X direction or Y direction, the distance L between the side wall area of ​​the packaging shell 10 and the light source substrate 11 is too large, which is not conducive to the structural design of the narrow frame of the backlight module. Figure 1 In the Z direction, in order to obtain a better LED light mixing effect and avoid defects such as grid patterns, the distance between the reflective cup 12 and the diffusion film 13, namely OD1, needs to have a certain numerical requirement, which leads to a larger thickness of the backlight module. For example, the thickness range of OD1 in the prior art is between 4 mm and 5 mm, for example, OD1 = 4.6 mm.

[0031] Based on one or more of the above problems, an embodiment of the present invention provides a display module. Figure 2 is a top view schematic diagram of a backlight module provided by an embodiment of the present invention, Figure 3 for Figure 2A schematic cross-sectional view of a backlight module along the AA' direction, see Figure 2 and Figure 3 A backlight module provided in an embodiment of the present invention includes a light source substrate 20, a reflective cup cover 30, a diffusion film 40, a beam splitter film 80 and a packaging shell 50. The backlight module 200 can be a direct-type backlight module, and the light source substrate 20 includes a plurality of light-emitting elements 21 arranged in an array. The light source substrate 20 serves as a carrier substrate for the light-emitting element 21, and the light-emitting element 21 can be an LED (Light Emitting Diode), a Micro-LED (Micro Light Emitting Diode Display), or a Mini-LED (Mini Light Emitting Diode). The embodiment of the present invention does not limit the type of the light-emitting element.

[0032] Taking Mini-LED as an example, Mini-LED is conducive to achieving the characteristics of LCD (Liquid Crystal Display, LCD, liquid crystal display panel) such as lightness, high image quality, and low power consumption. The performance level is close to OLED (Organic Light Emitting Diode Display, OLED, organic light-emitting display panel), and is superior to OLED in terms of brightness and color rendering. In addition, Mini-LED backlight can be combined with sophisticated local dimming (Local Dimming) technology to control the switching and brightness adjustment of the corresponding backlight area in real time, which can present high contrast, more vivid colors, and achieve a high dynamic range (High Dynamic Range Imaging, HDR) screen effect. Among them, a driving circuit electrically connected to the light-emitting element 21 is also provided above, below or inside the light source substrate 20, which is used to provide a light-emitting driving signal to the light-emitting element 21. The type of the driving circuit is not limited in the embodiment of the present invention.

[0033] Further, the reflective cup cover 30 is arranged on the side of the light source substrate 20 where the light emitting element 21 is arranged. The reflective cup cover 30 includes a plurality of reflective cups 31 connected to each other, an opening is arranged at the center of the reflective cup 31, and at least one light emitting element 21 is located in the opening. In the embodiment of the present invention, the reflective cup 31 can be arranged between two adjacent light emitting elements 21, and the reflective wall of the reflective cup 31 is arranged around the light emitting element 21. The light emitted by the light emitting element 21 is mixed after being reflected once or multiple times by the reflective wall of the reflective cup 31 and emitted toward the diffusion film 40, so that the light output brightness and display uniformity of the light emitting element 21 can be improved.

[0034] In other embodiments, two or more light-emitting elements 21 may be disposed in the central opening of the reflective cup 31 to meet different lighting requirements, which will not be shown one by one in the embodiments of the present invention.

[0035] It should be noted that the reflector cups 31 can be separately arranged, that is, the reflector cups 31 are independent structures, and each reflector cup 31 is respectively located between two adjacent light emitting elements 21. Alternatively, the reflector cups 31 can also be an integrated mesh structure, that is, a mesh structure formed by multiple reflector cups 31 surrounds the light emitting element 21 to form a reflector cup cover 30. The embodiment of the present invention does not limit the preparation method of the reflector cup cover 30.

[0036] The diffusion film 40 is located on the side of the reflective cup 30 away from the light source substrate 20, and at least part of the reflective cup 30 is in contact with the diffusion film 40. The diffusion film 40 can diffuse the light emitted by the light-emitting element 21, so that the brightness of the light emitted by the backlight module 200 is uniform. The diffusion film 40 and the reflective cup 30 can be fixed with a transparent light-guiding adhesive to prevent the diffusion film 40 from moving.

[0037] Different from the solution in the prior art where the reflective cup cover 30 is overlapped with the side plastic frame, Figure 3 In an embodiment of the present invention, the diffusion film 40 is directly disposed on the side of the reflective cup cover 30 away from the light source substrate 20, and at least a portion of the reflective cup cover 30 is in contact with the diffusion film 40. On the one hand, the distance between the diffusion film 40 and the light-emitting element 21 can be compressed, and the distance OD between the diffusion film 40 and the light source substrate 20 can be reduced, thereby achieving the purpose of reducing the thickness of the backlight module 200. Exemplarily, compared with the prior art, the distance OD between the diffusion film 40 and the light source substrate 20 can be reduced to 2 mm, and the thickness of the backlight module 200 can be reduced by at least 1.4 mm. On the other hand, the diffusion film 40 does not need to rest on the side frame glue, so the area where the frame glue is set in the side area of ​​the packaging shell 50 can be reduced, and the distance L' between the side area of ​​the packaging shell 50 and the light source substrate 20 is reduced, compared with the prior art. Figure 1 , L'<L, such an arrangement is conducive to realizing the structural design of the backlight narrow frame.

[0038] It should be noted that when the diffusion film 40 is lowered, the light mixing space between the diffusion film 40 and the reflective cup cover 30 is reduced, which may also aggravate the checkered pattern phenomenon. Based on this, in an embodiment of the present invention, at least one layer of dichroic film 80 is arranged on the side of the diffusion film 40 away from the light source substrate 20, wherein the dichroic film is an optical film that can better disperse the light. Exemplarily, a light spot is dispersed into multiple light spots, so as to eliminate the checkered pattern phenomenon and improve the display uniformity of the display module. Exemplarily, the thickness of the dichroic film 80 is 0.2mm to 0.4mm.

[0039] The light source substrate 20, the reflective cup cover 30, the beam splitter film 80 and the diffusion film 40 are all located in the area defined by the packaging shell 50, and the packaging shell 50 is used to package and protect the internal components. Among them, the packaging shell 50 can be an integrally formed die-cast structure, and its material can be made of aluminum alloy. Among them, a certain interval is set between the light source substrate 20, the reflective cup cover 30 and the diffusion film 40 and the side wall of the packaging shell 50 to provide spacing during packaging. After all the film layers are set, the diffusion film 40 and the packaging shell 50 can be filled with packaging glue and other materials for fixing.

[0040] It should be noted that the backlight module provided in the embodiment of the present invention also includes other film layers, such as a transparent optical film (Dual Brightness Enhancement Film, DBEF), etc., wherein DBEF is a reflective polarizer, which improves the brightness of the light emitted by the light-emitting element 21 by reflecting polarized light, thereby improving the light output effect of the backlight module 200. The various structures in the backlight module work together to realize the backlight function of the backlight module, which will not be shown one by one in the embodiment of the present invention.

[0041] Figure 4 for Figure 2 A schematic cross-sectional view of a backlight module along the AA' direction in FIG. Figure 2 and Figure 4 , the reflector cup 31 includes a first reflector cup 311 and a second reflector cup 312. The first reflector cup 311 surrounds the second reflector cup 312, and the first reflector cup 311 is located in the edge area of ​​the reflector cup cover 30. That is to say, the second reflector cup 312 is located in the central area of ​​the reflector cup cover 30 of the mesh structure, and the first reflector cup 311 is in the peripheral area. In the embodiment of the present invention, the first reflector cup 311 may only refer to the outermost circle of reflector cups 31 of the reflector cup cover 30. The first reflector cup 311 includes a first reflective wall 311a and a second reflective wall 311b. The first reflective wall 311a is close to the edge area of ​​the reflector cup cover 30, and the second reflective wall 311b is far away from the edge area of ​​the reflector cup cover 30. That is to say, the first reflective wall 311a is the outermost circle of reflective walls of the reflector cup cover 30.

[0042] In the prior art, the light mixing of the outermost circle of light emitting elements 21 is usually weak, and less light reaches the edge of the end surface of the diffusion film 40, which easily leads to low brightness at the edge of the diffusion film 40, resulting in low brightness at the edge of the display module, affecting the overall display uniformity. Figure 4 , the reflective wall of the first reflective cup 311 at the outermost periphery of the reflective cup cover 30 is designed differently to improve the brightness of the light emitted from the edge of the display module. For example, along the direction perpendicular to the plane where the light source substrate 20 is located ( Figure 4In the Z direction), the height d1 of the first reflective wall 311a is set to be smaller than the height d2 of the second reflective wall 311b, or the height d1 of the first reflective wall 311a can be set to be smaller than the height d3 of the reflective wall 312a of the second reflective cup 312. Wherein, d2 and d3 can be equal. In this way, a gap can be formed between the first reflective wall 311a and the diffusion film 40, and part of the light S emitted by the light-emitting element 21 leaks through the gap to the side area of ​​the packaging shell 50. The inner wall of the side area of ​​the packaging shell 50 can be polished or plated to improve the reflectivity of the inner wall of the side area of ​​the packaging shell 50, so that the part of the light S is reflected by the side area of ​​the packaging shell 50 and then emitted from the side area of ​​the diffusion film 40, thereby increasing the light in the edge area of ​​the diffusion film 40, improving the brightness of the edge area of ​​the diffusion film 40, and to a certain extent also increasing the mixed light of the outermost circle of light-emitting elements 21, thereby improving the luminous brightness of the edge area of ​​the backlight module 200, and achieving uniform overall light output brightness of the backlight module 10.

[0043] In other embodiments, reference Figure 4 , the angle a1 between the first reflecting wall 311a and the light source substrate 20 can be set to be smaller than the angle a2 between the second reflecting wall 311b and the light source substrate 20. Alternatively, it can also be designed that the angle a1 between the first reflecting wall 311a and the light source substrate 20 is smaller than the angle a3 between the reflecting wall 312a of the second reflecting cup 312 and the light source substrate 20. That is, a1<a2, a1<a3, wherein a2 and a3 can be the same or different, and such a setting is conducive to achieving the first reflecting wall 311a and the diffusion film 40 without contact, and a gap appears. Part of the light S emitted by the light-emitting element 21 in the first reflective cup 311 is emitted from the side gap of the reflective cup cover 30, and part of the light S is emitted from the edge area of ​​the diffusion film 40, thereby increasing the brightness of the edge area of ​​the diffusion film 40; part of the light S is emitted from the diffusion film 40 after being reflected once or multiple times between the first reflective wall 311a and the packaging shell 50, thereby increasing the luminous brightness of the edge area of ​​the backlight module 200 and achieving uniform overall light output brightness of the backlight module 10.

[0044] Based on the above embodiments, Figure 3 and Figure 4The packaging shell 50 includes a side region 51, the inner surface of the side region 51 is a plane, and the diffusion film 40 has no contact with the inner surface of the side region 51. In the embodiment of the present invention, the side region 51 of the packaging shell 50 can be a right-angle structure, the diffusion film 40 is directly overlapped on the reflective cup cover 30, and the diffusion film 40 has no contact with the inner surface of the side region 51 of the packaging shell 50. Among them, the reflective cup cover 30 can be made of a solid material and has a certain supporting effect. In this way, the side region 51 of the packaging shell 50 can be compressed toward the central area, reducing the distance L' between the side region 51 of the packaging shell 50 and the light source substrate 20, thereby reducing the frame thickness of the display module and realizing an extreme narrow frame design.

[0045] Figure 5 for Figure 2 A cross-sectional schematic diagram of a backlight module along the BB' direction, in some embodiments, refer to Figure 5 The inner surface of the side region 51 of the packaging shell 50 is a step surface M, along the direction perpendicular to the plane where the light source substrate 20 is located ( Figure 5 The step surface M of the diffusion film 40 and the side area 51 overlap. In the embodiment of the present invention, the side area 51 of the packaging shell 50 can be compressed toward the center to form a step surface M. The diffusion film 40 is in direct or indirect contact with the step surface M of the side area 51. The step surface M can play an auxiliary supporting role to prevent the entire weight of the diffusion film 40 from being concentrated on the reflective cup 30, thereby preventing the reflective cup 30 from collapsing. The present application compresses the side area 51 of the packaging shell 50 inward, which is conducive to reducing the distance between the side area 51 of the packaging shell 50 and the light source substrate 20, reducing the thickness of the frame of the packaging shell 50, and achieving an extremely narrow frame.

[0046] It should be noted that the outer surface of the side area 51 of the packaging shell 50 is recessed inward to form a step surface M. The packaging shell 50 can be an integrally formed die-cast structure, and its material can be aluminum alloy or other materials.

[0047] Continue to refer Figure 5 , the surface of part of the diffusion film 40 close to the light emitting element 21 is in contact with the step surface M of the side region 51, and the height h1 of the step surface M of the side region 51 relative to the light source substrate 20 is greater than or equal to the height d2 of the second reflection wall 311b of the first reflection cup 311 relative to the light source substrate 20. In the embodiment of the present invention, by reasonably controlling the height h1 of the step surface M of the side region 51 relative to the light source substrate 20, h1≥d2. On the basis that the diffusion film 40 is in direct contact with the reflection cup cover 30, part of the diffusion film 40 is directly placed on the step surface M of the side region 51, and the step surface M plays an auxiliary supporting role for the diffusion film 40, which can prevent the reflection cup cover 30 from collapsing.

[0048] Figure 6 for Figure 2 A schematic cross-sectional view of another backlight module along the BB' direction, Figure 7 for Figure 2 A schematic cross-sectional view of another backlight module along the BB' direction, Figure 8 for Figure 2 A schematic cross-sectional view of another backlight module along the BB' direction is shown in FIG.

[0049] Based on the above embodiments, Figure 6-Figure 8 The backlight module 200 further includes a reflective sheet 60, which at least partially covers the inner surface of the side region 51 and faces the light emitting element 21 and the diffusion film 40. In the embodiment of the present invention, a reflective sheet 60 can also be provided on the inner surface of the side region 51 of the package shell 50, facing the light emitting element 21 and the diffusion film 40, for example, a silver film is added to the inner surface of the side region 51 to increase the reflectivity of the inner surface of the side region 51. Part of the light S emitted from the side of the light emitting element 21 leaks out from above the first reflection wall 311a of the first reflection cup 311, and part of the light S is emitted directly from the edge region of the diffusion film 40, thereby increasing the brightness of the edge region of the diffusion film 40. Part of the light S is reflected back to the first reflection cup 311 by the reflective sheet 60 to form one or more reflections and then reaches the diffusion film 40 for emission, thereby increasing the mixed light of the outermost circle of light emitting elements 21, thereby improving the luminous brightness of the edge region of the backlight module 200.

[0050] For example, reference Figure 6 and Figure 7 The diffusion film 40 has no contact with the side area 51 of the packaging shell 50, the reflection sheet 60 is attached to the inner surface of the side area 51 of the packaging shell 50, and the height of the top of the reflection sheet 60 relative to the light source substrate 20 is greater than or equal to the height of the diffusion film 40 relative to the light source substrate 20. Figure 8 , part of the diffusion film 40 is directly overlapped on the step surface M of the side area 51, the reflection sheet 60 is attached to the side wall of the step surface M on the inner surface of the side area 51 of the packaging shell 50, and the height of the top of the reflection sheet 60 relative to the light source substrate 20 is less than or equal to the height of the diffusion film 40 relative to the light source substrate 20. In this way, the light emitted from the gap between the first reflection wall 311a and the diffusion film 40, or the light leaked from the end surface of the diffusion film 40, can be completely reflected back to the diffusion film 40 and then emitted, reducing the leakage of this part of the light and increasing the utilization rate of the light.

[0051] Fig. 9 for Figure 2 FIG. 1 is a cross-sectional schematic diagram of another backlight module along the BB' direction. Based on the above embodiment, refer to FIG. Fig. 9, the reflective sheet 60 is attached to the stepped surface M of the side area 51 of the packaging shell 50, and the surface of a part of the diffusion film 40 close to the light emitting element 21 is in contact with the reflective sheet 60 on the stepped surface M of the side area 51. In the embodiment of the invention, the reflective sheet 60 can also cover the inner side wall of the side area 51 of the packaging shell 50, and the diffusion film 40 is overlapped on the stepped surface M of the side area 51 of the packaging shell 50. In this way, the reflective sheet 60 reflects the light S emitted from the gap between the first reflective wall 311a and the diffusion film 40 and the light leaked from the side of the diffusion film 40 to the edge area of ​​the diffusion film 40, thereby improving the brightness of the edge area of ​​the diffusion film 40, and finally improving the luminous brightness of the edge area of ​​the backlight module 200.

[0052] Optional, reference Fig. 9 The step surface M shape along the side area 51 of the packaging shell 50, the shape of the reflective sheet 60 is Z-shaped, and thus it can cover the step surface M, increase the area of ​​the reflective sheet 60 in the side area 51, increase the reflection of the side area 51 on the side light emitted by the light-emitting element 21, improve the brightness of the edge area of ​​the diffusion film 40, and improve the luminous brightness of the edge area of ​​the backlight module 200.

[0053] Fig.10 for Figure 2 A cross-sectional schematic diagram of another backlight module along the BB' direction, see Fig.10 , the surface of the reflector 60 facing the light emitting element 21 and the diffusion film 40 is an inclined surface, and the bottom angle β is an acute angle. Fig.10 In the middle Z direction, the reflective surface of the reflective sheet 60 can also be designed as an inclined surface, which faces the light emitting element 21 and the diffusion film 40, and can reflect the light S to the side area of ​​the diffusion film 40, increase the light in the side area of ​​the diffusion film 40, and further improve the brightness of the side area of ​​the diffusion film 40. Among them, the size of the bottom angle β can be reasonably adjusted according to the actual reflection angle, and the bottom of the reflective sheet 60 can be placed on the light source substrate 20 to improve the stability of the reflective sheet 60.

[0054] It should be noted that in other embodiments of the present invention, the surface of the reflective sheet 60 facing the light-emitting element 21 and the diffusion film 40 can also be designed as an inclined surface to reflect more light toward the side area of ​​the diffusion film 40 to increase the brightness of the side area of ​​the diffusion film 40, which will not be shown one by one in the embodiments of the present invention.

[0055] Fig.11 for Figure 2 A schematic cross-sectional view of another backlight module along the BB' direction, Fig.12 for Figure 2 A schematic cross-sectional view of another backlight module along the BB' direction, Fig.13 for Figure 2FIG. 1 is a cross-sectional schematic diagram of another backlight module along the BB' direction. Based on the above embodiment, refer to FIG. Figure 11-13 The backlight module 200 further includes a light guide plate 70 , which is located between the light source substrate 20 and the side area 51 , and a light guide surface of the light guide plate 70 close to the light emitting element 21 contacts the first reflective wall 311 a of the first reflective cup 311 .

[0056] In an embodiment of the present invention, a light guide plate 70 is disposed between the first reflective wall 311a of the first reflective cup 311 and the side area 51. Part of the light S emitted by the light emitting element 21 is guided by the light guide plate 70 to the side area 51 of the packaging shell 50, and is reflected by the side area 51 to the edge area of ​​the diffusion film 40 and then emitted, thereby increasing the brightness of the edge area of ​​the diffusion film 40. At the same time, the optical path of this part of the light can also be increased, and the mixing distance can be increased, thereby increasing the luminous brightness of the edge area of ​​the backlight module 200 and improving the brightness uniformity of the backlight module 200.

[0057] Furthermore, the light guide plate 70 can also play a role in supporting the diffusion film 40. Fig.11 , the diffusion film 40 has no contact with the side area 51 of the packaging shell 50. On the basis that the diffusion film 40 is directly in contact with the reflective cup cover 30, the light guide plate 70 is disposed on the packaging shell 50 and is located between the first reflective wall 311a of the first reflective cup 311 and the side area 51 of the packaging shell 50, and is in contact with the diffusion film 40. Fig.12 The reflective sheet 60 is attached to the inner surface of the side area 51 of the packaging shell 50. On the basis that the diffusion film 40 is directly in contact with the reflective cup cover 30, the light guide plate 70 is arranged on the light source substrate 20, and the light guide surface of the light guide plate 70 close to the light emitting element 21 is in contact with the first reflective wall 311a of the first reflective cup 311, and the light guide surface of the light guide plate 70 away from the light source substrate 20 is in contact with the diffusion film 40. Fig.13 The reflective sheet 60 is attached to the inner surface of the side area 51 of the packaging shell 50, and part of the diffusion film 40 is directly overlapped on the reflective sheet 60 of the step surface M. The light guide surface of the light guide plate 70 close to the light emitting element 21 contacts the first reflection wall 311a of the first reflection cup 311, and the light guide surface of the light guide plate 70 away from the light source substrate 20 contacts the diffusion film 40. In this way, the light guide plate 70 can play a role in auxiliary support of the diffusion film 40 to prevent the reflection cup cover 30 from collapsing.

[0058] Fig.14 for Figure 2 A cross-sectional schematic diagram of another backlight module along the BB' direction is shown in FIG. Fig.14, the inner surface of the side region 51 is a stepped surface M; the light guide plate 70 is located between the diffusion film 40 and the stepped surface M of the side region 51, and the end surface of the light guide plate 70 away from the reflective cup 31 is provided with a reflective sheet 60. In the embodiment of the present invention, the light guide plate 70 is provided on the stepped surface M of the side region 51, a part of the diffusion film 40 is directly overlapped on the light guide plate 70, the reflective sheet 60 is attached to a part of the inner surface of the side region 51 of the packaging shell 50, the light guide surface of the light guide plate 70 on the side close to the light emitting element 21 is in contact with the first reflective wall 311a of the first reflective cup 311, and the light guide surface of the light guide plate 70 on the side away from the light source substrate 20 is in contact with the diffusion film 40. The light guide plate 70 is provided in the gap between the first reflective wall 311a of the first reflective cup 311 and the diffusion film 40, which can improve the utilization rate of light passing through the light guide plate 70 and reduce light loss.

[0059] Among them, reference Fig.14 In order to prevent the light guide plate 70 from moving, the light guide plate 70 can also be glued and fixed on the step surface M to prevent it from moving and falling off.

[0060] It should be noted that the embodiments of the present invention are Figure 4-Figure 14 The number of reflections and directions of the light S are only for illustrative purposes. In actual applications, due to the gap between the first reflective wall 311a of the first reflective cup 311 and the diffusion film 4, at least part of the light emitted from the side of the light-emitting element 21 or the light reflected by the reflective wall of the first reflective cup 311 passes through the gap and is reflected by the side area 51 of the packaging shell 50 and then emitted from the edge area of ​​the diffusion film 40, thereby increasing the brightness of the edge area of ​​the diffusion film 40 and improving the luminous brightness of the edge area of ​​the display module.

[0061] Based on the above embodiments, Figure 2 The packaging shell 50 includes a first side 51a, a second side 51b, a third side 51c, and a fourth side 51d. The first side 51a and the third side 51c are opposite to each other, and the second side 51b and the fourth side 51d are opposite to each other. The distance between the end face of the light source substrate 20 at the first side 51a and the outer side of the packaging shell 50 is greater than the distance between the end face of the light source substrate 20 and the outer side of the packaging shell 50 at the second side 51b, the third side 51c, and the fourth side 51d. In other words, the frame width of the first side 51a of the packaging shell 50 can be designed to be greater than the frame width of the second side 51b, the third side 51c, and the fourth side 51d.

[0062] Exemplarily, the inner surfaces of the side areas of the second side 51b, the third side 51c, and the fourth side 51d can be designed as stepped surfaces, and the inner surface of the side area of ​​the first side 51a can be a right-angle structure. The second side 51b, the third side 51c, and the fourth side 51d of the packaging shell 50 can be designed as extremely narrow frames, and power chips, driver chips and other devices can be packaged in the side area of ​​the first side 51a.

[0063] Fig.15 for Figure 2 FIG. 1 is a cross-sectional schematic diagram of another backlight module along the BB' direction. Based on the above embodiment, refer to FIG. Figure 2 At the positions of the second side 51b, the third side 51c, and the fourth side 51d, the distances between the end surface of the light source substrate 20 and the outer side of the packaging shell 50 are the same. In the embodiment of the present invention, the second side 51b, the third side 51c, and the fourth side 51d of the packaging shell 50 are designed to be extremely narrow frames with the same frame width.

[0064] For example, reference Fig.15 Taking the fourth side 51d as an example, the distance between the end surface of the light source substrate 20 and the outer side of the packaging shell 50 is calculated. The distance D between the end surface of the light source substrate 20 and the outer side of the packaging shell 50 satisfies: D=F+G+H+J.

[0065] Wherein, F is the distance between the light source substrate 20 and the inner surface of the packaging shell 50. G is the overlap length between the diffusion film 40 and the inner surface of the packaging shell 50. H is the distance between the diffusion film 40 and the inner surface of the packaging shell 50, and J is the distance between the inner surface and the outer surface of the packaging shell 50.

[0066] For example, the D of the packaging shell 50 at the second side 51b, the third side 51c, and the fourth side 51d is set to 4.5mm, and the D at the first side 51a is set to 6.2mm. It should be noted that in the embodiment of the present invention, F+G+H+J does not have an exact ratio or numerical relationship, and can be adjusted according to actual needs to achieve an extreme narrow frame design of the backlight module 200.

[0067] Based on the above embodiments, reference Figure 2-Figure 15, at least one layer of the diaphragm film 80 includes two stacked first diaphragm films and a second diaphragm film, and the optical parameters of the first diaphragm film and the second diaphragm film are the same. Among them, the optical parameters refer to the spectral wavelength, the ratio of transmittance and reflectivity, the light intensity splitting ratio, the polarization splitting ratio, etc. of the diaphragm film 80. It can also be understood that the structure and optical properties of the first diaphragm film and the second diaphragm film are exactly the same. In the embodiment of the present invention, the diaphragm film 80 with the same parameters can randomly refract the light, and the first diaphragm film and the second diaphragm film will scatter the light in turn, enhance the diffusion effect of the light, achieve better light mixing, and thus improve the uniformity of the display brightness of the display module.

[0068] Based on the same inventive concept, an embodiment of the present invention further provides a display device. Fig.16 A schematic diagram of a display device according to an embodiment of the present invention is provided. Fig.16 The display device 300 includes the backlight module 200 and the display panel 400 provided in the above embodiment. The backlight module 200 provides a light source for the display panel 400, and the display panel 400 includes a liquid crystal display panel. The structure of the display panel 40 is not described in detail in the embodiment of the present invention. Therefore, the display device also has the beneficial effects of the backlight module in the above embodiment. The similarities can be understood by referring to the above explanation of the backlight module, and will not be repeated below.

[0069] The display device 300 provided in the embodiment of the present invention can be Fig.16 The mobile phone shown can also be any electronic product with a display function, including but not limited to the following categories: televisions, laptops, desktop displays, tablet computers, digital cameras, smart bracelets, smart glasses, car displays, industrial control equipment, medical display screens, touch interactive terminals, etc. The embodiments of the present invention do not specifically limit this.

[0070] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, combinations and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A backlight module, characterized in that: include: A light source substrate, comprising a plurality of light emitting elements arranged in an array; A reflective cup cover, the reflective cup cover is located on a side of the light source substrate where the light-emitting elements are arranged; The reflective cup cover comprises a plurality of reflective cups connected to each other, an opening is arranged at the center of the reflective cup, at least one light emitting element is located in the opening, and a reflective wall of the reflective cup is arranged around the light emitting element; A diffusion film is located on a side of the reflective cup away from the light source substrate, and at least a portion of the reflective cup is in contact with the diffusion film; At least one layer of beam splitting film, located on a side of the diffusion film away from the light source substrate; The packaging shell, the light source substrate, the reflective cup cover, the diffusion film and the beam splitter film are all located in an area defined by the packaging shell.

2. The backlight module according to claim 1, characterized in that: The reflector cup includes a first reflector cup and a second reflector cup; the first reflector cup surrounds the second reflector cup, and the first reflector cup is located at the edge area of ​​the reflector cup cover; The first reflective cup comprises a first reflective wall and a second reflective wall, the first reflective wall is close to the edge area of ​​the reflective cup cover, and the second reflective wall is far away from the edge area of ​​the reflective cup cover; The first reflective wall has no contact with the diffusion film; Along a direction perpendicular to the plane where the light source substrate is located, the height of the first reflective wall is smaller than the height of the second reflective wall; or, the height of the first reflective wall is smaller than the height of the reflective wall of the second reflective cup.

3. The backlight module according to claim 2, characterized in that: The packaging shell includes a side region, the inner surface of the side region is a plane, and the diffusion film has no contact with the inner surface of the side region; or, The inner surface of the side area is a stepped surface; along a direction perpendicular to the plane where the light source substrate is located, the diffusion film overlaps with the stepped surface of the side area.

4. The backlight module according to claim 3, characterized in that: A portion of the surface of the diffusion film close to the light emitting element contacts the stepped surface of the side region, and a height of the stepped surface of the side region relative to the light source substrate is greater than or equal to a height of the reflective cup relative to the light source substrate.

5. The backlight module according to claim 3, characterized in that: Also includes reflective sheets; The reflective sheet at least partially covers the inner surface of the side area and faces the light emitting element and the diffusion film.

6. The backlight module according to claim 5, characterized in that: The reflective sheet is attached to the stepped surface of the side area, and a surface of a portion of the diffusion film close to the light emitting element is in contact with the reflective sheet on the stepped surface of the side area. The backlight module according to claim 6 , wherein the reflective sheet is in a Z-shape. 8 . The backlight module according to claim 5 , wherein a surface of the reflective sheet facing the light emitting element and the diffusion film is an inclined surface, and a bottom angle is an acute angle.

9. The backlight module according to claim 5, characterized in that: Also includes a light guide plate; The light guide plate is located between the light source substrate and the side area, and a light guide surface of the light guide plate close to the light emitting element is in contact with the first reflective wall of the first reflective cup.

10. The backlight module according to claim 9, characterized in that: The inner surface of the side area is a stepped surface; The light guide plate is located between the diffusion film and the stepped surface of the side area; and the reflective sheet is arranged on the end surface of the light guide plate away from the reflective cup.

11. The backlight module according to claim 3, characterized in that: The packaging shell includes a first side, a second side, a third side, and a fourth side; the first side is opposite to the third side, and the second side is opposite to the fourth side; The distance between the end surface of the light source substrate and the outer side of the packaging shell at the first side is greater than the distance between the end surface of the light source substrate and the outer side of the packaging shell at the second side, the third side, and the fourth side.

12. The backlight module according to claim 11, characterized in that: At the positions of the second side, the third side, and the fourth side, the distances between the end surface of the light source substrate and the outer side of the packaging shell are the same.

13. The backlight module according to claim 1, characterized in that: The at least one layer of the prismatic film comprises a first prismatic film and a second prismatic film which are stacked, and the first prismatic film and the second prismatic film have the same optical parameters.

14. A display device, characterized in that: The backlight module comprises the backlight module according to any one of claims 1 to 13.

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