Composite film, backlight module and display device

Abstract

The utility model discloses a composite film, a backlight module and a display device. The composite film comprises: a first substrate layer; the back coating layer is arranged on the bottom surface of the first base material layer; the first forming surface is arranged on the top surface of the first base material layer and comprises a plurality of first prisms, the top surfaces of the first prisms are planes, and the first forming surface is made of flexible glue; the second base material layer is arranged on one side, far away from the back coating, of the first forming surface; the second forming surface is arranged on the top surface of the second base material layer and is provided with a plurality of second prisms, and the longitudinal sections of the second prisms are triangular; in the extension direction of the first prisms, the top surface of each first prism is provided with a plurality of mutually spaced convex parts, the height of each convex part is flush with the top surface of the corresponding first prism, and the width of each convex part is greater than that of the top surface of the corresponding first prism; and the bottom surface of the second base material layer is directly attached to the top surfaces of the first prisms and the top surfaces of the convex parts. Through the arrangement, the problem that the thickness of the optical film of the backlight module in the related technology is large is solved.

Description

Technical Field

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

[0002] With the rapid development of display technology, LCD (Liquid Crystal Display) technology has emerged and become one of the most widely used display technologies today. Among them, ultra-thinness is a goal that LCD display technology has always pursued.

[0003] Display devices generally include a display panel and a backlight module. The backlight module includes optical films. The optical films of traditional backlight modules are mainly composed of four films: a lower diffuser film, a lower prism film, an upper prism film, and an upper diffuser film, which are bonded together by an adhesive layer. This often results in a relatively thick backlight module and display device, which is not conducive to achieving an ultra-thin design for large-size modules. Utility Model Content

[0004] This application provides a composite film, a backlight module, and a display device to solve the problem of excessively thick optical films in backlight modules in related technologies.

[0005] To solve the above-mentioned technical problems, one technical solution adopted in this application is: to provide a composite membrane, comprising:

[0006] First substrate layer;

[0007] A back coating is applied to the bottom surface of the first substrate layer;

[0008] A first molding surface is disposed on the top surface of the first substrate layer; the first molding surface includes a plurality of first prisms, the top surface of the first prisms being a plane; the material of the first molding surface is soft rubber.

[0009] The second substrate layer is disposed on the side of the first molding surface away from the back coating layer;

[0010] The second molding surface is disposed on the top surface of the second substrate layer; the second molding surface has a plurality of second prisms, and the longitudinal section of the second prisms is triangular;

[0011] Along the extension direction of the first prism, each of the first prisms has a plurality of spaced protrusions on its top surface. The height of the protrusions is flush with the top surface of the first prism, and the width is greater than the width of the top surface of the first prism. The bottom surface of the second substrate layer is directly attached to the top surface of the first prism and the top surface of the protrusions.

[0012] In some embodiments, the first molding surface further includes a first limiting wall, which is disposed around the periphery of the first prism; the bottom surface of the second substrate layer is provided with a second limiting wall, which is disposed around the periphery of the bottom surface of the second substrate layer corresponding to the first limiting wall; the first limiting wall and the second limiting wall cooperate to horizontally limit the second substrate layer and the first molding surface.

[0013] In some embodiments, the first limiting barrier is in the shape of a rectangular ring and is disposed around the periphery of the first prism along the circumference of the first substrate layer; the second limiting barrier is in the shape of a rectangular ring and is disposed along the circumference of the second substrate layer.

[0014] Along the circumference of the composite membrane, the inner side of the first limiting barrier is fitted to the outer side of the second limiting barrier.

[0015] In some embodiments, the first forming surface is formed by roller printing;

[0016] And / or, the second limiting barrier is formed by roller printing, or the second limiting barrier is integrally formed with the second substrate layer;

[0017] And / or, the second molding surface is formed by planar printing;

[0018] And / or, the material of the first substrate layer is polyethylene terephthalate;

[0019] And / or, the material of the second substrate layer is polyethylene terephthalate;

[0020] And / or, the material of the first molded surface is UV soft rubber;

[0021] And / or, the material of the second limiting barrier is UV soft rubber;

[0022] And / or, the material of the second molding surface is UV soft rubber, or, the material of the second molding surface is epoxy resin or polymethyl methacrylate.

[0023] In some embodiments, the extension directions of the first prism and the second prism are perpendicular to each other.

[0024] In some embodiments, the thickness of the composite film is 0.093 mm to 0.097 mm.

[0025] In some embodiments, the bottom surface of the second substrate layer is directly bonded to the top surface of the first prism and the top surface of the protrusion by an auxiliary pressing member; the auxiliary pressing member is flat and the flatness of the auxiliary pressing member is less than or equal to 0.01.

[0026] Before the auxiliary pressing component is pressed, the protrusion protrudes from the top surface of the first prism, and the width is equal to the width of the top surface of the first prism. The top surface of the protrusion is provided with a groove, and the depth of the groove is less than or equal to the thickness of the protrusion.

[0027] The auxiliary pressing member is configured such that the stroke of pressing the second substrate layer to move towards the first substrate layer is equal to the depth of the groove, so that after the auxiliary pressing member presses, the top surface of the first prism, the top surface of the protrusion, and the bottom surface of the groove are flush and directly attached to the bottom surface of the second substrate layer.

[0028] To solve the above-mentioned technical problems, another technical solution adopted in this application is to provide a backlight module, including any of the composite films described above.

[0029] To solve the above-mentioned technical problems, another technical solution adopted in this application is: to provide a display device, comprising:

[0030] The backlight module as described above;

[0031] The display panel is located on one side of the backlight module;

[0032] The backlight module is used to provide a backlight for the display panel.

[0033] In some embodiments, the backlight module includes a frame-backplate composite and an optical component. The frame-backplate composite includes a frame and a backplate connected to each other. The frame surrounds the backplate and forms a receiving space with the backplate. The optical component is disposed within the receiving space. The optical component includes a reflective sheet, a light guide plate, and the composite film stacked sequentially.

[0034] The display panel includes an array substrate and a counter substrate disposed opposite to each other, a first polarizer disposed on the side of the array substrate away from the counter substrate, and a second polarizer disposed on the side of the counter substrate away from the array substrate.

[0035] The thickness of the back plate is 0.15mm-0.25mm;

[0036] And / or, the thickness of the reflective sheet is 0.08mm-0.1mm;

[0037] And / or, the thickness of the light guide plate is 0.5mm-0.6mm;

[0038] And / or, the thickness of the array substrate is 0.15mm-0.25mm;

[0039] And / or, the thickness of the substrate is 0.15mm-0.25mm;

[0040] And / or, the thickness of the first polarizer is 0.081mm-0.091mm;

[0041] And / or, the thickness of the second polarizer is 0.072mm-0.082mm.

[0042] The beneficial effects of this application are as follows: Unlike existing technologies, this application discloses a composite film, a backlight module, and a display device. The composite film includes: a first substrate layer; a back coating layer disposed on the bottom surface of the first substrate layer; a first molding surface disposed on the top surface of the first substrate layer, the first molding surface including multiple first prisms, the top surface of the first prisms being flat, and the material of the first molding surface being soft rubber; a second substrate layer disposed on the side of the first molding surface away from the back coating layer; a second molding surface disposed on the top surface of the second substrate layer, the second molding surface having multiple second prisms, the longitudinal section of the second prisms being triangular; wherein, along the extending direction of the first prisms, the top surface of each first prism is provided with multiple mutually spaced protrusions, the height of the protrusions being flush with the top surface of the first prisms, and the width being greater than the width of the top surface of the first prisms; the bottom surface of the second substrate layer is directly bonded to the top surface of the first prisms and the top surface of the protrusions. By setting the first molding surface as a soft adhesive and providing multiple spaced protrusions on the top surface of the first prism, with the width of the protrusions greater than the width of the top surface of the first prism, the top surfaces of the protrusions and the top surface of the first prism can be directly contacted and bonded to the bottom surface of the second substrate layer by pressing the second substrate layer and the first substrate layer. This eliminates the need for a separate adhesive layer between the bottom surface of the second substrate layer and the top surface of the first prism, thus achieving a connection between the second substrate layer and the first molding surface. The adhesive layer is removed, and the back coating layer, the first substrate layer, the first molding surface, the second substrate layer, and the second molding surface are combined into a single composite film, effectively reducing the thickness of the composite film. This solves the problem in related technologies where the optical film thickness of the backlight module is too thick, hindering the ultra-thin design of large-size modules. This is beneficial for improving the performance of display devices and expanding their application scenarios. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0044] Figure 1 This is a cross-sectional schematic diagram of a display device provided in an embodiment of this application;

[0045] Figure 2 yes Figure 1 A cross-sectional schematic diagram of the provided display device after the bonding element is attached;

[0046] Figure 3 yes Figure 1 A schematic diagram of the structure of a composite film in the backlight module of the provided display device according to one embodiment;

[0047] Figure 4 yes Figure 3 A cross-sectional schematic diagram of the provided composite membrane;

[0048] Figure 5 yes Figure 3 A cross-sectional schematic diagram of one embodiment of the composite structure of the provided composite film, including the back coating layer, the first substrate layer, and the first molding surface;

[0049] Figure 6 yes Figure 5 A magnified view of a portion of region S;

[0050] Figure 7 yes Figure 5 A schematic diagram of the AA cross-section of the provided composite membrane;

[0051] Figure 8 yes Figure 5 A partial structural schematic diagram of the first forming surface of the provided composite membrane according to one embodiment;

[0052] Figure 9 yes Figure 5 A partial structural schematic diagram of another embodiment of the first forming surface of the provided composite membrane;

[0053] Figure 10 yes Figure 3 A cross-sectional schematic diagram of one embodiment of the composite structure of the provided composite film, consisting of a back coating layer, a first substrate layer, a first molding surface, and a second substrate layer;

[0054] Figure 11 yes Figure 3 A schematic cross-sectional view of the second substrate layer of the provided composite film;

[0055] Figure 12 yes Figure 3 A cross-sectional schematic diagram of the second forming surface of the provided composite film;

[0056] Figure 13 yes Figure 3 A cross-sectional schematic diagram of the composite structure of the second substrate layer and the second molding surface of the provided composite film.

[0057] Icon labels:

[0058] 300, Display device; 200, Display panel; 201, Array substrate; 202, Alignment substrate; 203, First polarizer; 204, Second polarizer; 205, Circuit board; 100, Backlight module; 1, Frame-backplate composite; 2, Frame; 3, Backplate; 4, Composite film; 41, Back coating; 42, First substrate layer; 43, First molding surface; 431, First prism; 432, First limiting barrier; 433, Protrusion; 434, Groove; 435, Protrusion structure; 44, Second substrate layer; 441, Second limiting barrier; 45, Second molding surface; 451, Second prism; 6, Optical component; 61, Reflector; 62, Light guide plate; 7, Light-shielding tape; 8, Reception space; 9, Light source; 10, Conductive tape. Detailed Implementation

[0059] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0060] The terms "first," "second," and "third" used in the embodiments of this application are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices.

[0061] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0062] See Figures 1 to 13 , Figure 1 This is a cross-sectional schematic diagram of a display device provided in an embodiment of this application. Figure 2 yes Figure 1 A cross-sectional schematic diagram of the provided display device after the bonding element is attached. Figure 3 yes Figure 1 A schematic diagram of the structure of one embodiment of the composite film for the backlight module of the provided display device. Figure 4 yes Figure 3 A cross-sectional schematic diagram of the provided composite membrane, Figure 5 yes Figure 3 A cross-sectional schematic diagram of one embodiment of the composite structure of the provided composite film, consisting of a back coating layer, a first substrate layer, and a first molding surface. Figure 6 yes Figure 5 A magnified view of a portion of region S. Figure 7 yes Figure 5 A schematic diagram of the AA section of the provided composite membrane. Figure 8 yes Figure 5 A partial structural schematic diagram of the first forming surface of the provided composite membrane according to one embodiment. Figure 9 yes Figure 5 A partial structural schematic diagram of another embodiment of the first forming surface of the provided composite film. Figure 10 yes Figure 3 A cross-sectional schematic diagram of one embodiment of the composite structure of the provided composite film, comprising a back coating layer, a first substrate layer, a first molding surface, and a second substrate layer. Figure 11 yes Figure 3 A cross-sectional schematic diagram of the second substrate layer of the provided composite film. Figure 12 yes Figure 3 A schematic cross-sectional view of the second forming surface of the provided composite film. Figure 13 yes Figure 3 A cross-sectional schematic diagram of the composite structure of the second substrate layer and the second molding surface of the provided composite film.

[0063] See Figure 1 and Figure 2 This application provides a display device 300, which includes a display panel 200 and a backlight module 100. The display panel 200 is disposed on one side of the backlight module 100, and the backlight module 100 is used to provide a backlight source for the display panel 200.

[0064] Specifically, such as Figure 1 and Figure 2The display panel 200 includes an array substrate 201 and a counter substrate 202 disposed opposite to each other, a liquid crystal layer (not shown) disposed between the array substrate 201 and the counter substrate 202, and a sealant (not shown) connecting the array substrate 201 and the counter substrate 202. The counter substrate 202 is located on the side of the array substrate 201 away from the backlight module 100. The display panel 200 also includes a first polarizer 203 and a second polarizer 204. The first polarizer 203 is disposed on the side of the array substrate 201 away from the counter substrate 202, and the second polarizer 204 is disposed on the side of the counter substrate 202 away from the array substrate 201.

[0065] Further, such as Figure 2 As shown, the array substrate 201 of the display panel 200 has a bonding area (not shown), and components such as a circuit board 205 are bonded to the bonding area for controlling the display panel 200 to realize the image display function.

[0066] like Figures 1 to 2 As shown, the backlight module 100 includes a frame-backplate composite 1 and an optical component 6. The frame-backplate composite 1 comprises a frame 2 and a backplate 3 connected to each other. The frame 2 and the backplate 3 are made of different materials, and the frame-backplate composite 1 is formed through a secondary molding process. Specifically, the frame 2 can be made of plastic. In some embodiments, the frame 2 surrounds the backplate 3 and forms a receiving space 8 with the backplate 3. The optical component 6 is disposed within the receiving space 8, and the display panel 200 is disposed on the side of the frame 2 of the backlight module 100 away from the backplate 3. It is understood that forming the frame-backplate composite 1 by secondary molding the frame 2 and the backplate 3 also helps to reduce the size of the frame 2 and facilitates a narrow bezel design.

[0067] In some implementations, such as Figure 1 As shown, the optical component 6 includes a reflective sheet 61, a light guide plate 62, and a composite film 4 stacked sequentially. The backlight module 100 can be an edge-lit backlight module or a direct-lit backlight module. Figure 2 As shown, in one embodiment, the backlight module 100 is a side-lit backlight module. The backlight module 100 includes a light source 9, which is disposed within the housing space 8 and located on one side of the light guide plate 62. It is used to provide backlight for the display panel 200 and also facilitates the ultra-thin design of the display device 300. Specifically, the light source 9 can be any light-emitting device such as an LED (light-emitting diode) or a fluorescent lamp.

[0068] Further, such as Figure 1As shown, in some embodiments, the backlight module 100 further includes a light-shielding tape 7. The light-shielding tape 7 is disposed on the side of the frame 2 away from the back plate 3 and extends to the side of the composite film 4 away from the light guide plate 62. That is, the two ends of the light-shielding tape 7 are respectively attached to the sides of the frame 2 and the composite film 4 away from the back plate 3, so as to block stray light between the gaps of the frame 2 and the composite film 4, prevent light leakage from the backlight module 100, and avoid light leakage in the edge area of ​​the display panel 200.

[0069] For details, see Figures 3 to 13 In some embodiments, the composite film 4 includes a back coating layer 41, a first substrate layer 42, a first molding surface 43, a second substrate layer 44, and a second molding surface 45, arranged sequentially. The back coating layer 41 is disposed on the bottom surface of the first substrate layer 42. Specifically, the back coating layer 41 is formed by coating the bottom surface of the first substrate layer 42 with back-coated particles. The first molding surface 43 is disposed on the top surface of the first substrate layer 42 and includes multiple first prisms 431. The top surface of each first prism 431 is planar, and the material of the first molding surface 43 is a soft adhesive. In one specific embodiment, the material of the first molding surface 43 is a UV soft adhesive. The second substrate layer 44 is disposed on the side of the first molding surface 43 away from the back coating layer 41. The second molding surface 45 is disposed on the top surface of the second substrate layer 44 and has multiple second prisms 451, the longitudinal section of which is triangular. Along the extension direction of the first prism 431, that is, along the length direction of the first prism 431, the top surface of each first prism 431 is provided with a plurality of mutually spaced protrusions 433. The height of the protrusions 433 is flush with the top surface of the first prism 431, and the width is greater than the width of the top surface of the first prism 431. The bottom surface of the second substrate layer 44 is directly attached to the top surface of the first prism 431 and the top surface of the protrusions 433.

[0070] It is understandable that by setting the first molding surface 43 as soft rubber and providing multiple spaced protrusions 433 on the top surface of the first prism 431, with the width of the protrusions 433 being greater than the width of the top surface of the first prism 431, the top surfaces of the protrusions 433 and the top surface of the first prism 431 can be pressed together with the bottom surface of the second substrate layer 44 to make them directly contact and adhere to each other, without the need for a space between the bottom surface of the second substrate layer 44 and the top surface of the first prism 431. By applying a separate adhesive layer, the second substrate layer 44 and the first molding surface 43 can be connected. By removing the adhesive layer and combining the back coating layer 41, the first substrate layer 42, the first molding surface 43, the second substrate layer 44, and the second molding surface 45 into a single composite film 4, the thickness of the composite film 4 is effectively reduced. This solves the problem in related technologies where the optical film of the backlight module 100 is too thick, which is not conducive to the ultra-thin design of large-size modules. This is beneficial to improving the display performance of the display device 300.

[0071] Specifically, the bottom surface of the second substrate layer 44 is directly bonded to the top surface of the first prism 431 and the top surface of the protrusion 433 by pressing with an auxiliary pressing member (not shown). Before pressing with the auxiliary pressing member, such as... Figures 5 to 9 As shown, the protrusion 433 protrudes from the top surface of the first prism 431, and its width is equal to the width of the top surface of the first prism 431. The top surface of the protrusion 433 is provided with a groove 434, and the depth of the groove 434 is less than or equal to the thickness of the protrusion 433. It is understood that before the top surface of the first prism 431 is attached to the bottom surface of the second substrate layer 44, the protrusion 433 protrudes from the top surface of the first prism 431 and a groove 434 is provided on the top surface of the protrusion 433. Since the material of the protrusion 433 is soft rubber, it is convenient to press the second substrate layer 44 and the first substrate layer 42 with the auxiliary pressing member, so that the second substrate layer 44 moves toward the first substrate layer 42 and squeezes the protrusion 433. The groove 434 also provides deformation space for the deformation of the protrusion 433, so that the protrusion 433 is squeezed toward the first prism 431 and deformed and extended along the four circumferential sides of the protrusion 433 to expel the air in the groove 434. This facilitates the direct attachment and adsorption of the bottom surface of the second substrate layer 44 with the top surface of the first prism 431 and the top surface of the protrusion 433 through the deformation and extension of the protrusion 433, thereby realizing the connection between the first molding surface 43 and the second substrate layer 44. Furthermore, the multiple protrusions 433 are spaced apart from each other, and the gap between two adjacent protrusions 433 can also provide deformable space for the protrusions 433 to deform and extend during the pressing process of the auxiliary pressing member. This avoids the problem that the protrusions 433 cannot be squeezed to be flush with the top surface of the first prism 431, thus failing to effectively achieve the top surface of both the protrusions 433 and the top surface of the first prism 431 to be in contact with the bottom surface of the second substrate layer 44.

[0072] In some implementations, such as Figure 8 As shown, the longitudinal cross-sectional shape of the position of the first prism 431 without the protrusion 433 is trapezoidal. The top surface of the first prism 431 is flat. Multiple protrusions 433 protruding from the top surface of the first prism 431 can be directly provided on the top surface of the first prism 431. The top surface of the protrusion 433 is provided with a groove 434. The multiple protrusions 433 are spaced apart from each other to provide space for the extension and deformation of the protrusions 433 during the process of the auxiliary pressing member pressing the first substrate layer 42 and the second substrate layer 44, so as to facilitate the air in the groove 434 to be discharged. The protrusions 433 are squeezed to be flush with the top surface of the first prism 431 and all are in contact with the bottom surface of the second substrate layer 44.

[0073] In another embodiment, such as Figure 9As shown, the top surface of the first prism 431 is a plane. Multiple protrusions 433 protruding from the top surface of the first prism 431 can be provided. These protrusions 433 are spaced apart from each other. Simultaneously, other protruding structures 435 are provided between adjacent protrusions 433. The height of the protruding structure 435 is less than the height of the protrusion 433, and the protruding structure 435 and the protrusion 433 are spaced apart. This allows the protruding structure 435 to be pressed during the process of the auxiliary pressing member pressing the first substrate layer 42 and the second substrate layer 44. When compressed, the air in the groove 434 is expelled, and both the protrusion 433 and the protrusion structure 435 can deform and extend in their circumferential direction. After the protrusion 433 is compressed to be flush with the top surface of the protrusion structure 435, both the protrusion 433 and the protrusion structure 435 can be pressed to be flush with the top surface of the first prism 431. Finally, the top surfaces of the protrusion 433, the protrusion structure 435, and the first prism 431 can all be attached to the bottom surface of the second substrate layer 44, thereby achieving the connection between the first molding surface 43 and the second substrate layer 44.

[0074] In some embodiments, an auxiliary pressing member is configured to press the second substrate layer 44 to move it towards the first substrate layer 42 by a stroke equal to or slightly less than the depth of the groove 434. This ensures that after the auxiliary pressing member presses, the top surface of the first prism 431 and the top surface of the protrusion 433 are flush with the bottom surface of the groove 434, and both can achieve a good and stable fit directly with the bottom surface of the second substrate layer 44. This achieves the connection between the first molding surface 43 and the second substrate layer 44, preventing the auxiliary pressing member from moving the second substrate layer 44 towards the first substrate layer 42 by a stroke greater than the depth of the groove 434, which could affect the height or angle of the first prism 431 and thus its performance, thereby avoiding any impact on the performance of the composite film 4. This pressing and bonding method ensures that the bond between the bottom surface of the second substrate layer 44 and the first molding surface 43 will not detach or peel off with temperature changes, resulting in high bonding stability.

[0075] Specifically, in some embodiments, the auxiliary pressing member is flat and its flatness is less than or equal to 0.01. For example, the auxiliary pressing member can be a steel plate or other flat structure with a flatness of less than or equal to 0.01. By pressing the second substrate layer 44 and the first substrate layer 42 on opposite sides respectively, the protrusion 433 at the top of the first prism 431 of the first forming surface 43 is deformed, so that it can be flush with the top surface of the first prism 431 and can be attached to the bottom surface of the second substrate layer 44, thereby achieving the bonding connection between the second substrate layer 44 and the first forming surface 43. It is understandable that setting the flatness of the auxiliary pressing component to less than or equal to 0.01, which is extremely flat, can more effectively press the second substrate layer 44 and the first substrate layer 42, so that the bottom surface of the second substrate layer 44 and the first forming surface 43 can fit more effectively, improving the bonding stability. At the same time, it can also effectively prevent the second substrate layer 44 of the composite film 4 from warping with the first substrate layer 42 and the first forming surface 43, which is beneficial to improving the flatness and structural stability of the composite film 4.

[0076] In some implementations, see Figures 4 to 13 The first molding surface 43 also includes a first limiting wall 432, which is disposed around the first prism 431. The bottom surface of the second substrate layer 44 is provided with a second limiting wall 441, which is disposed around the bottom surface of the second substrate layer 44 corresponding to the first limiting wall 432. The first limiting wall 432 and the second limiting wall 441 cooperate to horizontally limit the second substrate layer 44 and the first molding surface 43.

[0077] It is understood that the first molding surface 43 is made of UV soft adhesive. The first prism 431 of the first molding surface 43 is directly bonded to the bottom surface of the second substrate layer 44 under atmospheric pressure. In the horizontal direction, the friction between the first prism 431 and the bottom surface of the second substrate layer 44 limits the separation to prevent the top surface of the first prism 431 from peeling off or falling off from the bottom surface of the second substrate layer 44. In the above embodiment, by setting a first limiting barrier 432 around the first prism 431 of the first molding surface 43 and setting a corresponding second limiting barrier 441 on the bottom surface of the second substrate layer 44, the first limiting barrier can be used to limit the separation of the first prism 431 and the bottom surface of the second substrate layer 44. The cooperation between 432 and the second limiting barrier 441 achieves horizontal limiting between the first molding surface 43 and the second substrate layer 44, preventing misalignment between the first molding surface 43 and the second substrate layer 44 during the bonding process, or peeling or falling off the first molding surface 43 and the second substrate layer 44 when subjected to external forces in the horizontal direction after bonding, thus preventing the first molding surface 43 and the second substrate layer 44 from being effectively bonded together. The above setting helps to improve the bonding stability of the first molding surface 43 and the second substrate layer 44, thereby improving the structural stability and structural strength of the composite film 4.

[0078] In one specific implementation, such as Figures 4 to 13 As shown, the composite film 4 is rectangular, the first limiting wall 432 is a rectangular ring and is arranged around the periphery of the first prism 431 along the circumference of the first substrate layer 42, and the second limiting wall 441 is also a rectangular ring and is arranged along the circumference of the second substrate layer 44. Along the circumference of the composite film 4, the inner side of the first limiting wall 432 and the outer side of the second limiting wall 441 are attached together. That is, along the circumference of the composite film 4, corresponding first limiting walls 432 and second limiting walls 441 are provided at the corresponding positions on the four sides of the composite film 4. By setting the first limiting walls 432 and the second limiting walls 441 to be rectangular rings, the first forming surface 43 and the second substrate layer 44 can be limited in the horizontal direction at various positions along the circumference of the composite film 4, so as to improve the bonding stability of the first forming surface 43 and the second substrate layer 44, and improve the structural stability and structural strength of the composite film 4.

[0079] In other embodiments, the first limiting wall 432 and the second limiting wall 441 may not be rectangular rings. For example, the first limiting wall 432 may be a protrusion on the side of the first prism 431 near the edge of the first substrate layer 42 on the first molding surface 43, and the second limiting wall 441 may be a protrusion on the bottom surface of the second substrate layer 44. The protrusion may correspond to only one side of the composite film 4, or it may correspond to two, three or four sides of the composite film 4. The extension length of the protrusion may be less than the length of the side of the composite film 4 it corresponds to, or it may be equal to the length of the composite film 4 it corresponds to, so as to limit the horizontal direction of the first molding surface 43 and the second substrate layer 44 at the position where the first limiting wall 432 and the second limiting wall 441 are provided.

[0080] Specifically, in some embodiments, the first molding surface 43 is formed by roller printing. Specifically, the first prism 431 can be formed by roller printing, and the first limiting barrier 432 can also be formed by roller printing. Alternatively, the first limiting barrier 432 can be integrally formed with the first substrate layer 42. In some embodiments, the material of the first substrate layer 42 is polyethylene terephthalate (PET), and the material of the first limiting barrier 432 can be UV soft rubber or polyethylene terephthalate (PET). In some embodiments, the second limiting barrier 441 is formed by roller printing, or the second limiting barrier 441 can be integrally formed with the second substrate layer 44. The material of the second substrate layer 44 is polyethylene terephthalate (PET), and the material of the second limiting barrier 441 can be UV soft rubber or polyethylene terephthalate (PET). In some embodiments, the material of the second molding surface 45 may be UV soft rubber, or the material of the second molding surface 45 may be hot melt particles such as epoxy resin or polymethyl methacrylate (PMMA).

[0081] In one specific embodiment, both the first limiting barrier 432 and the second limiting barrier 441 can be made of polyethylene terephthalate (PET). Both the first limiting barrier 432 and the second limiting barrier 441 possess high strength, toughness, and wear resistance. When subjected to external force, the first limiting barrier 432 and the second limiting barrier 441 are not easily deformed, thus providing more effective limiting between the first molding surface 43 and the second substrate layer 44. In another specific embodiment, the first limiting barrier 432 can also be made of UV soft adhesive, and the second limiting barrier 441 can also be made of UV soft adhesive. This eliminates the need for separately preparing molds to form the first limiting barrier 432 and the second limiting barrier 441, thereby improving the preparation efficiency of the composite film 4 and reducing costs. The materials of the first limiting barrier 432 and the second limiting barrier 441 can be designed as needed, and this application does not limit them.

[0082] Specifically, in some embodiments, in the preparation of such Figure 3 In the process of creating the composite film 4 shown, a first substrate layer 42 and a second substrate layer 44 can be provided first. Both the first substrate layer 42 and the second substrate layer 44 are made of polyethylene terephthalate. Back coating particles are uniformly coated onto the bottom surface of the first substrate layer 42 using a roller to form a back coating layer 41. Then, a first forming surface 43, including multiple first prisms 431 and first limiting barriers 432, is formed on the top surface of the first substrate layer 42 using a roller. Specifically, the first forming surface 43 uses a UV soft adhesive material, which is cured after coating to form a composite film 43. Figure 5 The structure shown facilitates subsequent bonding of the first molding surface 43 to the bottom surface of the second substrate layer 44. The first prism 431 of the first molding surface 43, formed by roller printing, has multiple protrusions on its top surface that extend beyond the top surface of the first prism 431. The top surface of each protrusion has a groove 434, the depth of which is less than the height of the protrusion. This facilitates subsequent pressing to deform the protrusion and eliminate the groove 434 on its top surface, achieving flush alignment with the top surface of the first prism 431. In one specific embodiment, the top surface of the first prism 431 is rectangular, and the cross-sectional shape of the protrusions is also rectangular. Then, a second limiting barrier 441 is roller-printed around the bottom surface of the second substrate layer 44, forming a structure as shown... Figure 11 The structure shown will then be as follows: Figure 11 The second substrate layer 44 shown is as follows Figure 5 The composite structure of the back coating layer 41, the first substrate layer 42, and the first molding surface 43 shown is assembled with mutual alignment. Specifically, the second limiting wall 441 of the second substrate layer 44 cooperates with the first limiting wall 432 of the first molding surface 43 to achieve four-sided limiting, and the bottom surface of the second substrate layer 44 contacts the top surface of the first prism 431 and the top surface of the protrusion 433. Using an auxiliary pressing component with a flatness of less than or equal to 0.01, the first substrate layer 42 and the second substrate layer 44 are pressed against each other on the side of the back coating layer 41 away from the first substrate layer 42 and the top surface of the second substrate layer 44, respectively. The second substrate layer 44 is controlled during the pressing process. The depth of the groove 434 formed by the movement of the protrusion 433 to one side of the first substrate layer 42 is less than or equal to the depth of the top surface of the protrusion 433. This causes the protrusion 433 to deform and extend in the width direction, expelling the air from the groove 434. As a result, the top surface of the first prism 431, the top surface of the protrusion 433, and the bottom surface of the groove 434 are flush, and the width of the protrusion 433 is greater than the width of the top surface of the first prism 431. The top surface of the first prism 431, the top surface of the protrusion 433, and the bottom surface of the groove 434 are all directly bonded to the bottom surface of the second substrate layer 44. Atmospheric pressure is used to bond the two prisms together, and the bond will not fall off with temperature changes, forming a structure like... Figure 10The structure shown; finally, after the second substrate layer 44 and the first molding surface 43 have been bonded together, the second molding surface 45 is formed by pressing on the top plane of the second substrate layer 44 to avoid affecting the bonding stability between the second substrate layer 44 and the first molding surface 43, thereby preparing a composite film 4, so that the prepared composite film 4 can meet the design requirements of ultra-thin modules and is easy to apply to the ultra-thin design of large-size products.

[0083] like Figure 1 As shown, in some embodiments, the extension directions of the first prism 431 on the top surface of the first substrate layer 42 and the second prism 451 on the top surface of the second substrate layer 44 are perpendicular to each other. This arrangement can concentrate light from two directions, causing light to refract at multiple levels, optimizing the light propagation path, improving light propagation efficiency, concentrating more light in front of the backlight module 100, reducing unnecessary light scattering, making the light more concentrated and uniform, thereby improving the brightness of the light, and also making more effective use of the light source 9, reducing light loss, improving light utilization, and effectively reducing the generation of moiré patterns, thereby improving the image quality and making the display effect clearer and more natural.

[0084] Specifically, in some embodiments, the thickness of the composite film 4 is 0.093mm-0.097mm, and in one specific embodiment, the thickness of the composite film 4 is 0.095mm. It can be understood that by setting the structure of the composite film as described in the embodiments of this application, atmospheric pressure is used to directly press the top surface of the first prism 431 of the first forming surface 43 and the top surface of the protrusion 433 against the bottom surface of the second substrate layer 44, removing the adhesive layer between the first forming surface 43 and the second substrate layer 44, effectively reducing the thickness of the composite film 4. By eliminating the adhesive layer of optical films with traditional POP structures, the thickness of the composite film 4 can reach the aforementioned range, achieving an extremely thin single-sheet composite film 4 design. The thickness of the composite film 4 in this embodiment is set within the above-mentioned range. Unlike the traditional four-film optical film structure, this greatly reduces the thickness of the backlight module 100, making it easier to design an ultra-thin backlight module 100 and display device 300. The ultra-thin backlight module 100 can also be applied to large-size products, such as laptops, thus broadening the application scenarios of ultra-thin modules.

[0085] In some embodiments, the thickness of the back plate 3 is 0.15mm-0.25mm; in some embodiments, the thickness of the reflector 61 is 0.08mm-0.1mm; in some embodiments, the thickness of the light guide plate 62 is 0.5mm-0.6mm; in some embodiments, the thickness of the array substrate 201 is 0.15mm-0.25mm; in some embodiments, the thickness of the array substrate 202 is 0.15mm-0.25mm; in some embodiments, the thickness of the first polarizer 203 is 0.081mm-0.091mm; in some embodiments, the thickness of the first polarizer 203 is 0.072mm-0.082mm. It is understood that by setting the thickness of the above-mentioned structural components of the display device 300 within the above-mentioned range, the thickness of each structural component is relatively small, which is conducive to the display device 300 achieving an ultra-thin design. Combined with the narrow bezel design of the display device 300 such as the frame back panel composite component 1, the display device 300 of this application embodiment can simultaneously meet the characteristics of narrow bezel and ultra-thinness. Combining the characteristics of narrow bezel and ultra-thinness is more conducive to improving the performance of the display device 300, making the display device 300 of this application embodiment more advantageous.

[0086] In one specific embodiment, the thickness of the back plate 3 of the display device 300 is 0.2 mm, the thickness of the reflective sheet 61 is 0.09 mm, the thickness of the light guide plate 62 is 0.55 mm, the thickness of the composite film 4 is 0.09 mm, the thickness of the array substrate 201 is 0.2 mm, the thickness of the offset substrate 202 is 0.2 mm, the thickness of the first polarizer 203 is 0.086 mm, and the thickness of the second polarizer 204 is 0.077 mm. It can be understood that by specifically setting the thicknesses of the above-mentioned structural components of the display device 300 to the aforementioned values, it is more advantageous to reduce the thickness of the display device 300, enabling the design of an ultra-thin display device 300 of 1.6 mm. Combining narrow bezels and ultra-thin characteristics further improves the performance of the display device 300 and broadens the application scenarios of the ultra-thin display device 300.

[0087] like Figure 1 As shown, in some embodiments, the display device 300 further includes a conductive tape 10. After the display panel 200 and the backlight module 100 of the display device 300 are assembled, one end of the conductive tape 10 is attached to the surface of the substrate 202 away from the array substrate 201, and the other end extends from the outer side wall of the frame 2 to the surface of the back plate 3 away from the display panel 200, so as to attach both ends of the conductive tape 10 to the display panel 200 and the backlight module 100 respectively, so as to fix the display panel 200 and the backlight module 100 in a fixed assembly and improve the assembly stability of the display device 300.

[0088] The applicant used a conventional four-film optical film consisting of a lower diffuser film, a lower prism film, an upper prism film, and an upper diffuser film as the first comparative example, an optical film consisting of a lower diffuser film and a conventional composite film as the second comparative example, and the composite film 4 provided in the embodiments of this application as the experimental example. Three sets of identical experimental tests were conducted on the same five-axis optical machine and under the same experimental conditions.

[0089] Specifically, the thicknesses of the optical films in the first and second comparative examples and the composite film in the experimental example were tested, as were the thicknesses of the backlight modules 100 using the three sets of optical films, and the chromaticity coordinates of the center white point when the three backlight modules 100 were paired with the same display panel 200. The experimental results are shown in the table below:

[0090]

[0091]

[0092] Experimental results show that the thickness of the composite film 4 and the backlight module 100 in this embodiment are smaller than the thickness values ​​of the first and second comparative examples. Moreover, the center white point color is normal when paired with the same display panel 200. The composite film 4 and the backlight module 100 are thinner, which is more conducive to realizing ultra-thin module design and broadens the application scenarios of ultra-thin products.

[0093] The above description is merely an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A composite membrane, characterized in that, include: First substrate layer; A back coating is applied to the bottom surface of the first substrate layer; The first molding surface is located on the top surface of the first substrate layer; The first molding surface includes a plurality of first prisms, the top surface of the first prisms being a plane; the material of the first molding surface is soft rubber; The second substrate layer is disposed on the side of the first molding surface away from the back coating layer; The second molding surface is disposed on the top surface of the second substrate layer; the second molding surface has a plurality of second prisms, and the longitudinal section of the second prisms is triangular; Along the extension direction of the first prism, each of the first prisms has a plurality of spaced protrusions on its top surface. The height of the protrusions is flush with the top surface of the first prism, and the width is greater than the width of the top surface of the first prism. The bottom surface of the second substrate layer is directly attached to the top surface of the first prism and the top surface of the protrusions.

2. The composite membrane according to claim 1, characterized in that, The first molding surface further includes a first limiting wall, which is disposed around the periphery of the first prism; the bottom surface of the second substrate layer is provided with a second limiting wall, which is disposed around the periphery of the bottom surface of the second substrate layer corresponding to the first limiting wall; the first limiting wall and the second limiting wall cooperate to horizontally limit the second substrate layer and the first molding surface.

3. The composite membrane according to claim 2, characterized in that, The first limiting barrier is in the shape of a rectangular ring and is arranged around the periphery of the first prism along the circumference of the first substrate layer; the second limiting barrier is in the shape of a rectangular ring and is arranged along the circumference of the second substrate layer. Along the circumference of the composite membrane, the inner side of the first limiting barrier is fitted to the outer side of the second limiting barrier.

4. The composite membrane according to claim 2, characterized in that, The first forming surface is formed by roller printing; And / or, the second limiting barrier is formed by roller printing, or the second limiting barrier is integrally formed with the second substrate layer; And / or, the second molding surface is formed by planar printing; And / or, the material of the first substrate layer is polyethylene terephthalate; And / or, the material of the second substrate layer is polyethylene terephthalate; And / or, the material of the first molded surface is UV soft rubber; And / or, the material of the second limiting barrier is UV soft rubber; And / or, the material of the second molding surface is UV soft rubber, or, the material of the second molding surface is epoxy resin or polymethyl methacrylate.

5. The composite membrane according to claim 1, characterized in that, The extension directions of the first prism and the second prism are perpendicular to each other.

6. The composite membrane according to claim 1, characterized in that, The thickness of the composite membrane is 0.093mm-0.097mm.

7. The composite membrane according to any one of claims 1-6, characterized in that, The bottom surface of the second substrate layer is directly bonded to the top surface of the first prism and the top surface of the protrusion by an auxiliary pressing member; the auxiliary pressing member is flat and the flatness of the auxiliary pressing member is less than or equal to 0.

01. Before the auxiliary pressing component is pressed, the protrusion protrudes from the top surface of the first prism, and the width is equal to the width of the top surface of the first prism. The top surface of the protrusion is provided with a groove, and the depth of the groove is less than or equal to the thickness of the protrusion. The auxiliary pressing member is configured such that the stroke of pressing the second substrate layer to move towards the first substrate layer is equal to the depth of the groove, so that after the auxiliary pressing member presses, the top surface of the first prism, the top surface of the protrusion, and the bottom surface of the groove are flush and directly attached to the bottom surface of the second substrate layer.

8. A backlight module, characterized in that, include: The composite membrane as described in any one of claims 1-7.

9. A display device, characterized in that, include: The backlight module as described in claim 8; The display panel is located on one side of the backlight module; The backlight module is used to provide a backlight for the display panel.

10. The display device according to claim 9, characterized in that, The backlight module includes a frame-backplate composite and an optical component. The frame-backplate composite includes a frame and a backplate connected to each other. The frame surrounds the backplate and forms a receiving space with the backplate. The optical component is disposed within the receiving space. The optical component includes a reflective sheet, a light guide plate, and the composite film stacked sequentially. The display panel includes an array substrate and a counter substrate disposed opposite to each other, a first polarizer disposed on the side of the array substrate away from the counter substrate, and a second polarizer disposed on the side of the counter substrate away from the array substrate. The thickness of the back plate is 0.15mm-0.25mm; And / or, the thickness of the reflective sheet is 0.08mm-0.1mm; And / or, the thickness of the light guide plate is 0.5mm-0.6mm; And / or, the thickness of the array substrate is 0.15mm-0.25mm; And / or, the thickness of the substrate is 0.15mm-0.25mm; And / or, the thickness of the first polarizer is 0.081mm-0.091mm; And / or, the thickness of the second polarizer is 0.072mm-0.082mm.

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