Backlight module and display device

Abstract

The utility model provides a backlight module and a display device, and relates to the technical field of display. A plurality of optical films are arranged on one side of a back plate in the normal direction of the back plate; the plurality of bonding layers are arranged between every two adjacent optical films; part of the bonding layer is made of a shading material, and the annular middle frame is arranged on the side, away from the back plate, of the optical film and used for fixing the display panel; the first light shielding layer is arranged between the annular middle frame and the optical films and is attached to the annular middle frame, and the orthographic projection of the first light shielding layer on the back plate is overlapped with the orthographic projection of the annular middle frame on the back plate; wherein the first shading layer is provided with a notch, and the orthographic projection of the outline of the notch on the back plate is overlapped with the orthographic projection of the plurality of bonding layers on the back plate. The backlight module has a more uniform light emitting effect, so that the brightness of a display picture is more uniform, and the display effect is improved.

Description

Technical Field

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

[0002] With the advancement of display technology, the variety of display products is increasing, and the requirements for the performance of display products are also becoming higher.

[0003] In related technologies, for backlight modules used in automotive displays, in order to improve their mechanical stability, a light-shielding adhesive layer is usually used to fix multiple optical films in the backlight module together. In addition, a light-shielding layer is also set between the middle frame of the backlight module and the optical films. Under the combined effect of these factors, dark lines are prone to appear in the edge area of ​​the backlight module display surface. At a wide viewing angle, the local dark lines are more obvious in the edge area of ​​the backlight module display surface, which reduces the display effect of the backlight module. Summary of the Invention

[0004] The embodiments of this application provide a backlight module and a display device. The backlight module has a more uniform light emission effect, which makes the brightness of the displayed screen more uniform and improves the display effect.

[0005] The embodiments of this application adopt the following technical solutions:

[0006] In a first aspect, embodiments of this application provide a backlight module adapted to a display panel, the backlight module comprising:

[0007] Back panel;

[0008] Multiple optical films are disposed on one side of the back plate along the normal direction of the back plate;

[0009] Multiple adhesive layers are disposed between each pair of adjacent optical films; a portion of the material of the adhesive layers;

[0010] An annular frame is disposed on the side of the optical film away from the back plate, for fixing the display panel;

[0011] A first light-shielding layer is disposed between the annular frame and the plurality of optical films and attached to the annular frame. The orthographic projection of the first light-shielding layer on the back panel overlaps with the orthographic projection of the annular frame on the back panel.

[0012] The first light-shielding layer has a notch, and the outline of the notch overlaps with the orthographic projection of the plurality of adhesive layers on the back plate.

[0013] In a backlight module provided by an embodiment of this application, a portion of the adhesive layers are made of a light-transmitting material.

[0014] An embodiment of this application provides a backlight module in which the plurality of optical films include a light guide plate, a diffuser plate, a prism sheet, and a brightness enhancement film arranged sequentially along a direction away from the back plate, and the plurality of adhesive layers include a first adhesive layer, a second adhesive layer, and a third adhesive layer.

[0015] The first adhesive layer is disposed between the light guide plate and the diffuser plate, the second adhesive layer is disposed between the diffuser plate and the prism sheet, and the third adhesive layer is disposed between the brightness enhancement film and the prism sheet;

[0016] The light transmittance of the first adhesive layer is greater than that of the second adhesive layer, and the light transmittance of the first adhesive layer is greater than that of the third adhesive layer.

[0017] An embodiment of this application provides a backlight module, which further includes an adhesive portion disposed between the annular frame and the brightness enhancement film.

[0018] The orthographic projection of the adhesive portion on the back plate overlaps with the orthographic projection of the outline of the notch on the back plate, and the orthographic projection of the adhesive portion on the back plate does not overlap with the orthographic projection of the end of the first light-shielding layer on the back plate.

[0019] In a backlight module provided by an embodiment of this application, the light transmittance of the adhesive portion is greater than that of the second adhesive layer, and the light transmittance of the adhesive portion is greater than that of the third adhesive layer.

[0020] In a backlight module provided by an embodiment of this application, the materials of the first adhesive layer and the adhesive portion are both light-transmitting materials, and the materials of the second adhesive layer and the third adhesive layer are both light-shielding materials.

[0021] In a backlight module provided by an embodiment of this application, the first light-shielding layer includes a first end and a second end, the first end and the second end serving as the sidewalls of the notch;

[0022] The first end includes a first inclined surface, and the second end includes a second inclined surface. The first inclined surface has a first angle with the normal direction of the back plate, and the second inclined surface has a second angle with the normal direction of the back plate. Both the first angle and the second angle are acute angles.

[0023] In a backlight module provided by an embodiment of this application, the second adhesive layer includes a third end and a fourth end. The orthographic projection of the third end on the back plate overlaps with the orthographic projection of the first end on the back plate, and the orthographic projection of the fourth end on the back plate overlaps with the orthographic projection of the second end on the back plate.

[0024] In a backlight module provided by an embodiment of this application, the third end includes a third inclined surface, and the fourth end includes a fourth inclined surface;

[0025] The second adhesive layer extends in the direction from the first end to the second end. The orthographic projection of the first inclined surface on the reference surface intersects with the orthographic projection of the third inclined surface on the reference surface. The orthographic projection of the second inclined surface on the reference surface intersects with the orthographic projection of the fourth inclined surface on the reference surface. The reference surface is parallel to the extension direction of the adhesive portion and parallel to the normal direction of the back plate.

[0026] In a backlight module provided by an embodiment of this application, the third adhesive layer includes a fifth end and a sixth end. The orthographic projection of the fifth end on the back plate overlaps with the orthographic projection of the first end on the back plate, and the orthographic projection of the sixth end on the back plate overlaps with the orthographic projection of the second end on the back plate.

[0027] In a backlight module provided by an embodiment of this application, the fifth end includes a fifth inclined surface, and the sixth end includes a sixth inclined surface;

[0028] The third adhesive layer extends in the direction from the first end to the second end. The orthographic projection of the first inclined surface on the reference surface intersects with the orthographic projection of the fifth inclined surface on the reference surface. The orthographic projection of the second inclined surface on the reference surface intersects with the orthographic projection of the sixth inclined surface on the reference surface. The reference surface is parallel to the extension direction of the adhesive portion and parallel to the normal direction of the back plate.

[0029] In a backlight module provided by an embodiment of this application, the light guide plate includes a boss structure, which is used to fix the diffuser plate, the prism sheet, and the brightness enhancement film.

[0030] The orthographic projections of the adhesive portion, the first adhesive layer, the second adhesive layer, and the third adhesive layer on the back plate overlap with the orthographic projections of the boss structure on the back plate.

[0031] An embodiment of this application provides a backlight module, wherein the backlight module includes a third light-shielding layer that covers the boss structure.

[0032] An embodiment of this application provides a backlight module, wherein the backlight module includes a fourth light-shielding layer, the fourth light-shielding layer covering the edge region of the surface of the diffuser plate away from the back plate.

[0033] In a backlight module provided by an embodiment of this application, the orthographic projections of the second adhesive layer and the third adhesive layer on the back panel overlap, the orthographic projection of the third adhesive layer on the back panel is located within the orthographic projection of the first adhesive layer on the back panel, and the orthographic projection of the adhesive portion on the back panel is located within the orthographic projection of the second adhesive layer on the back panel.

[0034] An embodiment of this application provides a backlight module, which further includes a backlight source and a reflective portion. The backlight source and the reflective portion are both arranged on both sides of the light guide plate parallel to the normal direction of the back plate.

[0035] Secondly, embodiments of this application provide a display device, including a display panel and a backlight module as described in any one of the first aspects; the display panel is disposed on the light-emitting side of the backlight module.

[0036] This application provides a backlight module and a display device. The backlight module includes a back plate, multiple optical films, multiple adhesive layers, an annular frame, and a first light-shielding layer. The multiple optical films are disposed on one side of the back plate along the normal direction of the back plate. The multiple adhesive layers are disposed between each pair of adjacent optical films. Some of the adhesive layers are made of light-shielding material. The annular frame is disposed on the side of the optical films away from the back plate and is used to fix the display panel. The first light-shielding layer is disposed between the annular frame and the multiple optical films and is attached to the annular frame. The orthographic projection of the first light-shielding layer on the back plate overlaps with the orthographic projection of the annular frame on the back plate. The first light-shielding layer has a notch, and the orthographic projection of the outline of the notch on the back plate overlaps with the orthographic projection of the multiple adhesive layers on the back plate.

[0037] In the backlight module provided in the embodiments of this application, a notch is provided on the first light-shielding layer, and the outline of the notch overlaps with the orthographic projection of the plurality of adhesive layers on the back panel. Since light can pass through the notch, the overlap between the first light-shielding layer and the plurality of adhesive layers at the notch location is avoided, thereby reducing the light-shielding effect at that location, uniformizing the brightness in different areas of the backlight module, and thus giving the backlight module a more uniform light emission effect, resulting in more uniform brightness of the displayed image and improved display performance.

[0038] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0039] 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.

[0040] Figure 1 A schematic diagram of the structure of a backlight module in a related art provided for an embodiment of this application;

[0041] Figure 2 A schematic diagram illustrating uneven brightness of a backlight module in a related art, provided as an embodiment of this application;

[0042] Figure 3 A schematic diagram of the structure of a backlight module provided for an embodiment of this application;

[0043] Figure 4 A partial enlarged view of a backlight module at the notch location in the first light-shielding layer, provided for an embodiment of this application;

[0044] Figure 5 A diagram showing the positional relationship and brightness analysis of the first light-shielding layer notch location relative to other adhesive layers, provided for embodiments of this application;

[0045] Figure 6 A diagram showing the positional relationship and brightness analysis of the notch location in the first light-shielding layer relative to other adhesive layers in an embodiment of this application;

[0046] Figure 7 A diagram showing the positional relationship and brightness analysis of the notch location in the first light-shielding layer relative to other adhesive layers in a third embodiment of this application;

[0047] Figure 8 A partial enlarged view of another backlight module provided for an embodiment of this application at the location of the notch in the first light-shielding layer;

[0048] Figure 9 A schematic diagram showing uniform brightness of a backlight module display screen provided for an embodiment of this application;

[0049] Figure 10 This is a cross-sectional structural diagram of a display device provided for an embodiment of this application. Detailed Implementation

[0050] 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 some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0051] In the embodiments of this application, the terms "first", "second", "third", "fourth" are used to distinguish the same or similar items with essentially the same function and effect, only for the purpose of clearly describing the technical solution of the embodiments of this application, and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated.

[0052] In the embodiments of this application, the terms "upper" and "lower" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0053] In the description of this specification, the terms "one embodiment," "some embodiments," "exemplary embodiment," "example," "specific example," or "some examples," etc., are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this application. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics mentioned may be included in any suitable manner in any one or more embodiments or examples.

[0054] In the embodiments of this application, "multiple" means two or more, and "at least one" means one or more, unless otherwise explicitly defined.

[0055] The features such as "parallel," "perpendicular," and "identical" used in the embodiments of this application include features in the strict sense of "parallel," "perpendicular," and "identical," as well as cases where "approximately parallel," "approximately perpendicular," and "approximately identical" include certain tolerances. Taking into account the measurement and the tolerances associated with the measurement of a specific quantity (e.g., limitations of the measurement system), they represent the acceptable deviation range for a specific value as determined by a person skilled in the art. For example, "approximately" can mean within one or more standard deviations, or within 3% or 5% of said value.

[0056] Unless the context otherwise requires, throughout the specification and claims, the term "comprising" is interpreted as open and encompassing, that is, "including, but not limited to".

[0057] The polygons used in this specification are not strictly defined; they can be approximate triangles, parallelograms, trapezoids, pentagons, or hexagons, and may have minor deformations due to tolerances.

[0058] In this specification, "electrical connection" and "coupling" include situations where components are connected together by elements that have some electrical function. There are no particular limitations on what constitutes an "electrical function," as long as it allows for the transmission and reception of electrical signals between the connected components. Examples of "electrical functions" include not only electrodes and wiring, but also switching elements such as transistors, resistors, inductors, capacitors, and other components with various functions.

[0059] Figure 1 This invention provides a backlight module from a related technology. In this technology, to address vibration-related issues, currently, in automotive projects, optical films are fixed together using double-sided adhesive tape J. The optical brightness enhancement film 24 and the prism sheet 23 are both fixed to the light guide plate 21 via the diffuser plate 22. To increase adhesion, the double-sided adhesive tape J between the diffuser plate 22 and the light guide plate 21 is designed to be relatively long. The double-sided adhesive tape J between the optical brightness enhancement film 24 and the middle frame 3 mainly serves as an auxiliary fixation. Because the expansion rates of the optical brightness enhancement film 24 and the middle frame 3 differ significantly, excessively long double-sided adhesive tape J poses a risk of wrinkling of the optical brightness enhancement film 24; therefore, it is generally designed to be at its shortest possible length. The double-sided adhesive tape (between the optical brightening film 24 and the prism sheet 23, and between the prism sheet 23 and the diffuser plate 22) is generally designed to have the same length. In addition, in order to prevent the light guide plate protrusion 21t from having a bright spot, the double-sided adhesive tape J needs to be black and white. At the same time, since the middle frame 3 is silver-white, the light from the backlight shines on the middle frame 3 (e.g., the iron frame), and is reflected by the iron frame to the top layer film, resulting in a narrow bright line band visible around the backlight. In order to improve the bright line problem of the iron frame project, a black light-shielding layer 4 needs to be added to the lower surface of the iron frame. When applying the black light-shielding layer 4, it should be applied along the edge of the display area (AA area) of the iron frame.

[0060] Under the combined effect of the aforementioned light-blocking factors, dark lines are prone to appear at the edges of the backlight module's display surface, such as... Figure 2 As shown, at wide viewing angles, the dark lines at the edges of the backlight module's display surface are more noticeable, as indicated by the arrows, which reduces the display effect of the backlight module.

[0061] When the distance between the adhesive layer J and the display area (AA area) is less than or equal to 3.5 mm, the aforementioned dark lines become more noticeable.

[0062] Based on this, such as Figure 3As shown, an embodiment of this application provides a backlight module adapted to a display panel, the backlight module comprising:

[0063] Back panel 1;

[0064] Multiple optical films 2 are disposed on one side of the back plate 1 along the normal direction of the back plate 1;

[0065] Multiple adhesive layers (e.g., n1, n2, and n3) are disposed between every two adjacent optical films 2; some of the adhesive layers are made of light-shielding material;

[0066] The annular frame 3 is located on the side of the optical film 2 away from the back plate 1 and is used to fix the display panel.

[0067] The first light-shielding layer 4 is disposed between the annular frame 3 and multiple optical films 2 and attached to the annular frame 3. The orthographic projection of the first light-shielding layer 4 on the back plate 1 overlaps with the orthographic projection of the annular frame 3 on the back plate 1.

[0068] The first light-shielding layer 4 has a notch 4q, and the orthographic projection of the outline of the notch 4q on the back plate 1 overlaps with the orthographic projection of multiple adhesive layers (e.g., n1, n2 and n3) on the back plate 1.

[0069] It should be noted that the aforementioned optical film layer 2 may include a light guide plate 21, a diffuser plate 22, a prism sheet 23, and a brightness enhancement film 24.

[0070] The material of the first light-shielding layer 4 is a non-metallic light-shielding material, such as a black coating or a black film. For example, the first light-shielding layer 4 is a light-shielding PET film. PET is a resin material: polyethylene terephthalate.

[0071] Since the first light-shielding layer 4 is attached to the annular frame 3, the shape and size of the first light-shielding layer 4 vary depending on the annular frame 3.

[0072] In an exemplary embodiment, since the annular frame 3 has a reflective effect, the first light-shielding layer 4 is used to cover the lower surface of the annular frame 3 (the surface of the annular frame 3 near the back panel 1) to reduce the reflective effect and improve the light efficiency of the backlight module.

[0073] However, it should be noted that, because a notch 4q is provided on the first light-shielding layer 4, the reflected light from the lower surface of the annular frame 3 (the surface of the annular frame 3 near the back plate 1) at the notch 4q position is not blocked by the first light-shielding layer 4. Specifically, as shown in... Figure 3As shown, the orthographic projection of the notch 4q on the back plate 1 overlaps with the orthographic projection of the multiple adhesive layers on the back plate 1. Therefore, the reflected light from the lower surface of the annular frame 3 (the surface of the annular frame 3 near the back plate 1) at the notch 4q location is mainly blocked by the multiple adhesive layers below.

[0074] It should be noted that in this specification, "overlap exists" means at least partial overlap, including both partial overlap and complete overlap.

[0075] In the backlight module provided in the embodiments of this application, such as Figure 3 As shown, by setting a notch 4q on the first light-shielding layer 4, the orthographic projection of the outline of the notch 4q on the back plate 1 overlaps with the orthographic projection of multiple adhesive layers on the back plate 4q. Since light can pass through the notch 4q, this avoids the overlap between the first light-shielding layer 4 at the notch 4q and the multiple adhesive layers (e.g., n1, n2, and n3), thereby reducing the light-shielding effect at that location, uniformizing the brightness in different areas of the backlight module, and thus making the backlight module have a more uniform light emission effect, making the brightness of the displayed image more uniform, and improving the display effect.

[0076] In a backlight module provided by an embodiment of this application, some of the adhesive layers (e.g., n1, n2, and n3) are made of light-transmitting material.

[0077] It should be noted that light-transmitting materials refer to materials with a certain light transmittance, such as materials with a light transmittance greater than or equal to 50%, or materials with a light transmittance greater than or equal to 60%.

[0078] In a backlight module provided by an embodiment of this application, such as Figure 3 As shown, the plurality of optical films include a light guide plate 21, a diffuser plate 22, a prism sheet 23, and a brightness enhancement film 24 arranged sequentially along a direction away from the back plate 1, and the plurality of adhesive layers include a first adhesive layer n1, a second adhesive layer n2, and a third adhesive layer n3.

[0079] The first adhesive layer n1 is disposed between the light guide plate 21 and the diffuser plate 22, the second adhesive layer n2 is disposed between the diffuser plate 22 and the prism sheet 23, and the third adhesive layer n3 is disposed between the brightness enhancement film 23 and the prism sheet 24.

[0080] The light transmittance of the first adhesive layer n1 is greater than that of the second adhesive layer n2, and the light transmittance of the first adhesive layer n1 is greater than that of the third adhesive layer n3.

[0081] There is no limitation on whether the light transmittance of the second adhesive layer n2 and the third adhesive layer n3 are equal; this can be determined based on the actual design.

[0082] In the embodiments of this application, the light transmittance of the first adhesive layer n1 is set to be greater than that of the second adhesive layer n2, and the light transmittance of the first adhesive layer n1 is greater than that of the third adhesive layer n3. Thus, the first adhesive layer n1 has a higher light transmittance, allowing light to pass through at the notch 4q mentioned above. This avoids overlap between the first light-shielding layer 4 at the notch 4q and the multiple adhesive layers (e.g., n1, n2, and n3). Furthermore, it increases the light transmittance of the first adhesive layer n1 overlapping with the notch 4q, thereby reducing the light-shielding effect at that location. This uniformizes the brightness in different areas of the backlight module, resulting in a more uniform light emission effect and improved display quality.

[0083] The light guide plate is made of optical-grade acrylic / PC sheet. Light guide points are then printed onto the bottom surface of the optical-grade acrylic sheet using a high-tech material with extremely high refractive index and no light absorption, employing laser engraving, V-shaped cross-grid engraving, or UV screen printing technology. The optical-grade acrylic sheet absorbs light emitted from the light source and causes it to linger on its surface. When the light reaches each light guide point, the reflected light diffuses in various angles, breaking the reflection condition and exiting from the front of the light guide plate. Through various density and size light guide points, the light guide plate can emit light uniformly.

[0084] A prism film (BEF, or Brightness Enhancement Film), also known as a prism sheet, is used to improve the brightness of the front of a display screen.

[0085] The material of the diffuser plate can include any one of glass, polystyrene (PS), polycarbonate (PC), polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), and acrylic (PMMA).

[0086] Double Brightness Enhancing Film (DBEF) is a thin-film reflective polarizer that improves brightness across the entire viewing area of ​​an LCD. This optical film, DBEF, is a high-performance, high-transparency film primarily composed of silicone material and special microspheres. Its name derives from its unique bidirectional electronic filtering effect.

[0087] Of course, in some embodiments, the optical film 2 may also include a quantum dot film, a diffuser sheet, and a composite film.

[0088] Quantum dot films (QDEF) are a technology that uses quantum dot phosphors and polymers to form a film. For example, the material of a quantum dot film can include perovskite quantum dot material, and its thickness is generally around 100 μm.

[0089] The material of the diffuser sheet can be the same as that of the diffuser plate; the composite film, while improving light efficiency, also serves as a protective film for the diffuser plate, quantum dot film, and diffuser sheet, protecting them from scratches or damage.

[0090] The aforementioned backlight module is used to provide a light source with sufficient brightness and uniform brightness distribution to the display device. The specific structure of the backlight module and the type of light-emitting element (light source) within it are not limited here.

[0091] The color of the light emitted by the light source in the aforementioned backlight module is not specified here.

[0092] For example, the light-emitting element in the backlight module can emit white light; or, the light-emitting element in the backlight module can emit blue light.

[0093] When the light-emitting element in the aforementioned backlight module emits blue light, various quantum dot patterns can be set to convert blue light into other colors of light (such as white light).

[0094] In a backlight module provided by an embodiment of this application, such as Figure 3 As shown, the backlight module also includes an adhesive part m, which is disposed between the annular frame 3 and the brightness enhancement film 24.

[0095] The orthographic projection of the adhesive part m on the back plate 1 overlaps with the orthographic projection of the outline of the notch 4q on the back plate 1, and the orthographic projection of the adhesive part m on the back plate 1 does not overlap with the orthographic projection of the end of the first light-shielding layer 4 on the back plate.

[0096] It should be noted that, since the orthographic projection of the adhesive part m on the back plate 1 overlaps with the orthographic projection of the outline of the notch 4q on the back plate 1, and the orthographic projection of the adhesive part m on the back plate 1 does not overlap with the orthographic projection of the end of the first light-shielding layer 4 on the back plate, thus, combined with the attached... Figure 4 As shown, the dimension H2 of the adhesive part m in its extension direction is smaller than the dimension H1 of the notch 4q in the same direction.

[0097] In a backlight module provided by an embodiment of this application, the light transmittance of the adhesive part m is greater than that of the second adhesive layer n2, and the light transmittance of the adhesive part m is greater than that of the third adhesive layer n3.

[0098] Here, the transmittance between the aforementioned adhesive portion m and the first adhesive layer n1 is not limited.

[0099] For example, the light transmittance of the adhesive portion m is greater than the light transmittance of the first adhesive layer n1.

[0100] For example, the light transmittance of the adhesive portion m is less than the light transmittance of the first adhesive layer n1.

[0101] For example, the light transmittance of the adhesive portion m is approximately equal to the light transmittance of the first adhesive layer n1.

[0102] In a backlight module provided by an embodiment of this application, the materials of the first adhesive layer n1 and the adhesive part m are both light-transmitting materials, and the materials of the second adhesive layer n2 and the third adhesive layer n3 are both light-shielding materials.

[0103] In this specification, light-transmitting material can be understood as a material with a light transmittance greater than 50%, and light-blocking material can be understood as a material with a light-blocking rate greater than 50%.

[0104] In some embodiments, the light transmittance of the light-transmitting material may be greater than or equal to 60%; or, the light transmittance of the light-transmitting material may be greater than or equal to 70%.

[0105] In some embodiments, the shading rate of the shading material may be greater than or equal to 60%; or, the shading rate of the shading material may be greater than or equal to 70%.

[0106] In a backlight module provided by an embodiment of this application, such as Figure 4 As shown, the first light-shielding layer 4 includes a first end D1 and a second end D2, with the first end D1 and the second end D2 serving as the sidewalls of the notch q4.

[0107] The first end D1 includes a first inclined surface X1, and the second end D2 includes a second inclined surface X2. The first inclined surface X1 has a first included angle α with the normal direction of the back plate 1, and the second inclined surface X2 has a second included angle β with the normal direction of the back plate 1. Both the first included angle α and the second included angle β are acute angles.

[0108] In an exemplary embodiment, the difference in angle between the first included angle α and the second included angle β is less than or equal to 5°. This ensures that the first inclined plane X1 and the second inclined plane X2 are arranged as symmetrically as possible, which helps to improve the uniformity of the brightness of the emitted light.

[0109] like Figure 5As shown, if the slope is not designed, due to fluctuations or deviations in the actual process, if there is a gap between the end of the second adhesive layer n2 (or the third adhesive layer n3) and the sidewall of the notch 4q, too much light will pass through, which may cause local areas of the backlight module to be bright; if the end of the second adhesive layer n2 (or the third adhesive layer n3) overlaps with the sidewall of the notch 4q, too little light will pass through, which may cause local areas of the backlight module to be dark.

[0110] In the embodiments of this application, such as Figure 6 As shown, by setting the first end D1 to include a first inclined surface X1 and the second end D2 to include a second inclined surface X2, the first inclined surface X1 has a first included angle α with the normal direction of the back plate 1, and the second inclined surface X2 has a second included angle β with the normal direction of the back plate 1, both the first included angle α and the second included angle β being acute angles; thus, even when there is a gap between the end of the second adhesive layer n2 and the side wall of the notch 4q, or when the end of the second adhesive layer n2 overlaps with the side wall of the notch 4q, the brightness loss or the transmitted light is moderate, and the brightness change in this area is small and difficult for the human eye to perceive, thereby improving the brightness uniformity of the edge area of ​​the backlight module and improving the display effect.

[0111] In a backlight module provided by an embodiment of this application, combined with Figure 4 and Figure 8 As shown, the second adhesive layer n2 includes a third end D3 and a fourth end D4. The orthographic projection of the third end D3 on the back plate 1 overlaps with the orthographic projection of the first end D1 on the back plate 1, and the orthographic projection of the fourth end D4 on the back plate overlaps with the orthographic projection of the second end D2 on the back plate.

[0112] In an exemplary embodiment, combined with Figure 4 and Figure 8 As shown, the orthographic projection of the third end D3 on the back plate 1 overlaps with the orthographic projection of the first end D1 on the back plate 1, and the orthographic projection of the fourth end D4 on the back plate overlaps with the orthographic projection of the second end D2 on the back plate.

[0113] In an exemplary embodiment, the orthographic projection of the third end D3 on the back plate 1 overlaps with the orthographic projection of the first end D1 on the back plate 1, and the overlapping area is the first region; the orthographic projection of the fourth end D4 on the back plate overlaps with the orthographic projection of the second end D2 on the back plate, and the overlapping area is the second region, and the areas of the first region and the second region are approximately equal.

[0114] In a backlight module provided by an embodiment of this application, combined with Figure 4 and Figure 8 As shown, the third end D3 includes a third inclined surface X3, and the fourth end D4 includes a fourth inclined surface X4.

[0115] The second adhesive layer n2 extends in the direction from the first end D1 to the second end D2. The orthographic projection of the first inclined surface X1 on the reference surface intersects with the orthographic projection of the third inclined surface X3 on the reference surface. The orthographic projection of the second inclined surface X2 on the reference surface intersects with the orthographic projection of the fourth inclined surface X4 on the reference surface. The reference surface is parallel to the extension direction of the adhesive part m and parallel to the normal direction of the back plate 1.

[0116] The aforementioned "reference surface" is a virtual concept used to describe the relative positional relationship between the first inclined surface X1, the second inclined surface X2, the third inclined surface X3, and the fourth inclined surface X4. This "reference surface" is perpendicular to the backplate 1, parallel to the extension direction of the adhesive portion m, and parallel to the normal direction of the backplate 1. It can be understood that the aforementioned "reference surface" is a cross-section of the backlight module perpendicular to the backplate 1.

[0117] In an exemplary embodiment, the orthographic projection of the first inclined plane X1 onto the reference plane intersects with the orthographic projection of the third inclined plane X3 onto the reference plane, and the included angle between them is the third included angle; the orthographic projection of the second inclined plane X2 onto the reference plane intersects with the orthographic projection of the fourth inclined plane X4 onto the reference plane, and the included angle between them is the fourth included angle; the third included angle and the fourth included angle can be approximately equal.

[0118] Intersection includes, but is not limited to, perpendicularity.

[0119] like Figure 5 As shown, if the slope is not designed, due to fluctuations or deviations in the actual process, if there is a gap between the end of the second adhesive layer n2 (or the third adhesive layer n3) and the sidewall of the notch 4q, too much light will pass through, which may cause local areas of the backlight module to be bright; if the end of the second adhesive layer n2 (or the third adhesive layer n3) overlaps with the sidewall of the notch 4q, too little light will pass through, which may cause local areas of the backlight module to be dark.

[0120] like Figure 7As shown, based on the first end D1 of the first light-shielding layer 4 including a first inclined surface X1 and the second end D2 including a second inclined surface X2, the third end D3 of the second adhesive layer n2 is further provided to include a third inclined surface X3 and the fourth end D4 includes a fourth inclined surface X4; and the orthographic projection of the first inclined surface X1 on the reference surface intersects with the orthographic projection of the third inclined surface X3 on the reference surface, and the orthographic projection of the second inclined surface X2 on the reference surface intersects with the orthographic projection of the fourth inclined surface X4 on the reference surface; in this way, even if there is a gap between the end of the second adhesive layer n2 and the sidewall of the notch 4q, or if the end of the second adhesive layer n2 and the sidewall of the notch 4q overlap, the brightness loss or the transmitted light can cancel each other out, making the brightness change in this area small and difficult for the human eye to perceive, thereby improving the brightness uniformity of the edge area of ​​the backlight module and improving the display effect.

[0121] In a backlight module provided by an embodiment of this application, such as Figure 4 As shown, the third adhesive layer n3 includes a fifth end D5 and a sixth end D6. The orthographic projection of the fifth end D5 on the back plate 1 overlaps with the orthographic projection of the first end D1 on the back plate 1, and the orthographic projection of the sixth end D6 on the back plate 1 overlaps with the orthographic projection of the second end D2 on the back plate.

[0122] In an exemplary embodiment, the orthographic projection of the fifth end D5 on the back plate 1 overlaps with the orthographic projection of the first end D1 on the back plate 1, and the orthographic projection of the sixth end D6 on the back plate 1 overlaps with the orthographic projection of the second end D2 on the back plate 1.

[0123] In an exemplary embodiment, the orthographic projection of the fifth end D5 on the back plate 1 completely overlaps with the orthographic projection of the third end D3 on the back plate 1, and the orthographic projection of the sixth end D6 on the back plate 1 completely overlaps with the orthographic projection of the fourth end D4 on the back plate 1. It can be understood that this includes a situation where the orthographic projection of the second adhesive layer n2 on the back plate 1 completely overlaps with the orthographic projection of the third adhesive layer n3 on the back plate 1.

[0124] In an exemplary embodiment, the orthographic projection of the fifth end D5 on the back plate 1 overlaps with the orthographic projection of the first end D1 on the back plate 1, and the overlapping area is the third region; the orthographic projection of the sixth end D6 on the back plate 1 overlaps with the orthographic projection of the second end D2 on the back plate 1, and the overlapping area is the fourth region; the areas of the third region and the fourth region are approximately equal.

[0125] In an exemplary embodiment, the areas of the first region and the third region are approximately equal, and the areas of the second region and the fourth region are approximately equal.

[0126] In an exemplary embodiment, the areas of the first region, the second region, the third region, and the fourth region are all approximately equal.

[0127] In a backlight module provided by an embodiment of this application, such as Figure 4 As shown, the fifth end D5 includes a fifth inclined surface X5, and the sixth end D6 includes a sixth inclined surface X6;

[0128] The third adhesive layer n3 extends in the direction from the first end D1 to the second end D2. The orthographic projection of the first inclined surface X1 on the reference surface intersects with the orthographic projection of the fifth inclined surface X5 on the reference surface. The orthographic projection of the second inclined surface X2 on the reference surface intersects with the orthographic projection of the sixth inclined surface X6 on the reference surface. The reference surface is parallel to the extension direction of the adhesive part m and parallel to the normal direction of the back plate 1.

[0129] The reference plane here can be the same plane as the "reference plane" mentioned earlier.

[0130] In an exemplary embodiment, the orthographic projection of the first inclined plane X1 on the reference plane intersects with the orthographic projection of the fifth inclined plane X5 on the reference plane, and the included angle between them is the fifth included angle; the orthographic projection of the second inclined plane X2 on the reference plane intersects with the orthographic projection of the sixth inclined plane X6 on the reference plane, and the included angle between them is the sixth included angle; the fifth included angle and the sixth included angle can be approximately equal.

[0131] In an exemplary embodiment, the third and fifth included angles may be approximately equal; the fourth and sixth included angles may be approximately equal.

[0132] In an exemplary embodiment, the third and fourth included angles, and the fifth and sixth included angles, can all be approximately equal.

[0133] like Figure 7 As shown, based on the first end D1 of the first light-shielding layer 4 including a first inclined surface X1 and the second end D2 including a second inclined surface X2, a third adhesive layer n3 is further provided, including a fifth end D5 and a sixth end D6. The fifth end D5 includes a fifth inclined surface X5, and the sixth end D6 includes a sixth inclined surface X6. Furthermore, the orthographic projection of an inclined surface X1 on the reference surface intersects with the orthographic projection of the fifth inclined surface X5 on the reference surface, and the orthographic projection of the second inclined surface X2 on the reference surface intersects with the orthographic projection of the sixth inclined surface X6 on the reference surface. In this way, even if there is a gap between the end of the third adhesive layer n3 and the sidewall of the notch 4q, or if the end of the third adhesive layer n3 overlaps with the sidewall of the notch 4q, the brightness loss or the transmitted light can cancel each other out, making the brightness change in this area small and difficult for the human eye to perceive. This can improve the brightness uniformity of the edge area of ​​the backlight module and improve the display effect.

[0134] In a backlight module provided by an embodiment of this application, such as Figure 3As shown, the light guide plate 21 includes a boss structure 21t, which is used to fix the diffuser plate 22, the prism sheet 23 and the brightness enhancement film 24.

[0135] Among them, the orthographic projections of the adhesive part m, the first adhesive layer n1, the second adhesive layer n2 and the third adhesive layer n3 on the back plate 1 overlap with the orthographic projections of the boss structure 21t on the back plate 1.

[0136] In an exemplary embodiment, for better assembly between the film layers, such as Figure 3 As shown, the adhesive part m, the first adhesive layer n1, the second adhesive layer n2 and the third adhesive layer n3 are all provided with recessed parts at the positions where they overlap with the boss structure 21t, in order to avoid the boss structure 21t.

[0137] An embodiment of this application provides a backlight module, wherein the backlight module includes a third light-shielding layer ( Figure 3 (Not shown in the drawing), the third light-shielding layer covers the boss structure 21t.

[0138] For example, a third light-shielding layer covers the light-emitting surface of the boss structure 21t. It can be understood that the third light-shielding layer covers the surface of the boss structure 21t away from the back plate 1.

[0139] In the embodiments of this application, since the protrusion structure 21t on the light guide plate 21 also has a light guiding function, it is very easy to present bright spots on the display surface of the backlight module, resulting in uneven brightness or bright spots in the screen of the backlight module; by setting the backlight module to include a third light-shielding layer ( Figure 3 (Not shown in the image), the third light-shielding layer covers the convex structure 21t, which can improve the problem of uneven brightness or bright spots and improve the display effect.

[0140] An embodiment of this application provides a backlight module, wherein the backlight module includes a fourth light-shielding layer ( Figure 3 (Not shown in the drawing), the fourth light-shielding layer covers the edge area of ​​the surface of the diffuser plate 22 away from the back plate 1.

[0141] In an exemplary embodiment, the planar pattern of the fourth light-shielding layer may be annular, used to cover the edge region of the surface of the diffuser 22 away from the back plate 1.

[0142] In the embodiments of this application, since the protrusion structure 21t on the light guide plate 21 also has a light guiding function, it is very easy to present bright spots on the display surface of the backlight module, resulting in uneven brightness or bright spots in the screen of the backlight module; by setting the backlight module to include a fourth light-shielding layer ( Figure 3 (Not shown in the image), the fourth light-shielding layer covers the edge area of ​​the surface of the diffuser plate 22 away from the back plate 1. The fourth light-shielding layer can block the light leakage of the boss structure 21t, thereby improving the problem of uneven brightness or bright spots and improving the display effect.

[0143] Figure 9 This application provides illustrations showing the improvement in dark lines of the backlight module in embodiments of the present application. Figure 9 As can be seen, at a wide viewing angle but a narrow field of view, the brightness of the edge area of ​​the backlight module is uniform, with no bright or dark lines appearing, thus improving the display effect.

[0144] In a backlight module provided by an embodiment of this application, such as Figure 3 As shown, the orthographic projections of the second adhesive layer n2 and the third adhesive layer n3 on the back plate 1 overlap. The orthographic projection of the third adhesive layer n3 on the back plate 1 is located within the orthographic projection of the first adhesive layer n1 on the back plate 1. The orthographic projection of the adhesive part m on the back plate 1 is located within the orthographic projection of the second adhesive layer n2 on the back plate 1.

[0145] In a backlight module provided by an embodiment of this application, such as Figure 10 As shown, the backlight module also includes a backlight source 9 and a reflective part (including F1 and F2). The backlight source 9 and the reflective part (including F1 and F2) are both arranged on both sides of the light guide plate 21 parallel to the normal direction of the back plate 1.

[0146] The reflective part includes a first reflective part F1 and a second reflective part F2, which are used to reflect lateral light and improve the light emission efficiency from the front, thereby improving the light efficiency.

[0147] In the embodiments of this application, such as Figure 10 The light path diagram shown illustrates that by setting the first adhesive layer 21 and the adhesive part m as light-transmitting materials, more light emitted from the backlight source 9 can be emitted from the light-emitting surface during the reflection process of the film layer inside the backlight module, especially increasing the total amount of light emitted from the adhesive part m. Figure 10 The light rays marked ① in the middle are used to increase the brightness of the edge area of ​​the backlight module display surface, thereby improving the brightness uniformity of the backlight module.

[0148] It should be noted that the backlight module also includes other components and structures. This description only focuses on the structures related to the invention point. Other components and structures included in the backlight module can be found in relevant technologies and will not be elaborated here.

[0149] Embodiments of this application provide a display device, such as... Figure 10 As shown, it includes a display panel PNL and a backlight module as described above; the display panel PNL is disposed on the light-emitting side of the backlight module.

[0150] In the display device provided by the embodiments of this application, a notch 4q is provided on the first light-shielding layer 4, and the orthographic projection of the outline of the notch 4q on the back plate 1 overlaps with the orthographic projection of multiple adhesive layers on the back plate 4q. Since light can pass through the notch 4q, the overlap between the first light-shielding layer 4 provided at the notch 4q and the multiple adhesive layers (e.g., n1, n2, and n3) is avoided, thereby reducing the light-shielding effect at that location, uniformizing the brightness of different areas in the backlight module, and thus making the backlight module have a more uniform light emission effect, making the brightness of the displayed image more uniform, and improving the display effect.

[0151] The display device provided in the embodiments of this application has the characteristics of high manufacturing yield, stable performance, and good product quality.

[0152] Those skilled in the art will understand that the display device provided in this application also has the advantages of the backlight module of any of the above embodiments.

[0153] For example, a cover plate 7 is also provided on the side of the display panel PNL away from the backlight module.

[0154] For example, the above-described display device further includes a connecting layer 6 disposed between the display panel PNL and the cover plate 7, for fixing the display panel PNL and the cover plate 7 and improving the reliability of the cover plate 7.

[0155] In addition, a buffer section 8 is provided between the cover plate 7 and the back plate 1, a circuit board FPC is connected to the bonding area of ​​the display panel PNL, and a support section is provided between the display panel PNL and the annular frame 3.

[0156] The circuit board PFC can also be electrically connected to the backlight module.

[0157] It should be noted that, due to the large number of film layers in the display device, Figure 10 In this paper, the structure of the first light-shielding layer 4 is omitted. The specific structure and location of the first light-shielding layer 4 can be found in the previous introduction and explanation, and will not be repeated here.

[0158] In an exemplary embodiment, the display panel described above may be a liquid crystal display (LCD). For example, the liquid crystal display panel may include twisted nematic (TN) type, vertical alignment (VA) type, in-plane switching (IPS) type, and advanced super dimension switch (ADS) type.

[0159] The liquid crystal display panel may include an array substrate and a color filter substrate, with a liquid crystal layer LC (not shown in the figure) located between the array substrate and the color filter substrate; it may also include a first polarizer and a second polarizer located on both sides of the array substrate and the color filter substrate, respectively.

[0160] The structure and components included in the array substrate and color filter substrate of the above-mentioned display panel are not limited here, and can be determined according to the product design.

[0161] For example, the above-mentioned display device may be an in-vehicle display device.

[0162] The display device provided in this application can be any product or component with display function, such as a display module, mobile phone, tablet computer, television, monitor, laptop computer, digital photo frame, in-vehicle display device, smartwatch, fitness wristband, personal digital assistant, etc.

[0163] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A backlight module adapted to a display panel, characterized in that, The backlight module includes: Back panel; Multiple optical films are disposed on one side of the back plate along the normal direction of the back plate; Multiple adhesive layers are disposed between each pair of adjacent optical films; some of the adhesive layers are made of a light-shielding material. An annular frame is disposed on the side of the optical film away from the back plate, for fixing the display panel; A first light-shielding layer is disposed between the annular frame and the plurality of optical films and attached to the annular frame. The orthographic projection of the first light-shielding layer on the back panel overlaps with the orthographic projection of the annular frame on the back panel. The first light-shielding layer has a notch, and the outline of the notch overlaps with the orthographic projection of the plurality of adhesive layers on the back plate.

2. The backlight module according to claim 1, characterized in that, A portion of the multiple adhesive layers is made of a light-transmitting material; The plurality of optical films include a light guide plate, a diffuser plate, a prism sheet, and a brightness enhancement film arranged sequentially in a direction away from the back plate, and the plurality of adhesive layers include a first adhesive layer, a second adhesive layer, and a third adhesive layer. The first adhesive layer is disposed between the light guide plate and the diffuser plate, the second adhesive layer is disposed between the diffuser plate and the prism sheet, and the third adhesive layer is disposed between the brightness enhancement film and the prism sheet; The light transmittance of the first adhesive layer is greater than that of the second adhesive layer, and the light transmittance of the first adhesive layer is greater than that of the third adhesive layer.

3. The backlight module according to claim 2, characterized in that, The backlight module also includes an adhesive portion disposed between the annular frame and the brightness enhancement film. The orthographic projection of the adhesive portion on the back plate overlaps with the orthographic projection of the outline of the notch on the back plate, and the orthographic projection of the adhesive portion on the back plate does not overlap with the orthographic projection of the end of the first light-shielding layer on the back plate.

4. The backlight module according to claim 3, characterized in that, The light transmittance of the adhesive portion is greater than that of the second adhesive layer, and the light transmittance of the adhesive portion is greater than that of the third adhesive layer.

5. The backlight module according to claim 4, characterized in that, The materials of the first adhesive layer and the adhesive portion are both light-transmitting materials, while the materials of the second adhesive layer and the third adhesive layer are both light-shielding materials.

6. The backlight module according to claim 5, characterized in that, The first light-shielding layer includes a first end and a second end, which serve as the sidewalls of the notch; The first end includes a first inclined surface, and the second end includes a second inclined surface. The first inclined surface has a first angle with the normal direction of the back plate, and the second inclined surface has a second angle with the normal direction of the back plate. Both the first angle and the second angle are acute angles.

7. The backlight module according to claim 6, characterized in that, The second adhesive layer includes a third end and a fourth end, wherein the orthographic projection of the third end on the back plate overlaps with the orthographic projection of the first end on the back plate, and the orthographic projection of the fourth end on the back plate overlaps with the orthographic projection of the second end on the back plate.

8. The backlight module according to claim 7, characterized in that, The third end includes a third inclined surface, and the fourth end includes a fourth inclined surface; The second adhesive layer extends in the direction from the first end to the second end. The orthographic projection of the first inclined surface on the reference surface intersects with the orthographic projection of the third inclined surface on the reference surface. The orthographic projection of the second inclined surface on the reference surface intersects with the orthographic projection of the fourth inclined surface on the reference surface. The reference surface is parallel to the extension direction of the adhesive portion and parallel to the normal direction of the back plate.

9. The backlight module according to any one of claims 6 to 8, characterized in that, The third adhesive layer includes a fifth end and a sixth end, wherein the orthographic projection of the fifth end on the back plate overlaps with the orthographic projection of the first end on the back plate, and the orthographic projection of the sixth end on the back plate overlaps with the orthographic projection of the second end on the back plate.

10. The backlight module according to claim 9, characterized in that, The fifth end includes a fifth inclined surface, and the sixth end includes a sixth inclined surface; The third adhesive layer extends in the direction from the first end to the second end. The orthographic projection of the first inclined surface on the reference surface intersects with the orthographic projection of the fifth inclined surface on the reference surface. The orthographic projection of the second inclined surface on the reference surface intersects with the orthographic projection of the sixth inclined surface on the reference surface. The reference surface is parallel to the extension direction of the adhesive portion and parallel to the normal direction of the back plate.

11. The backlight module according to any one of claims 3 to 10, characterized in that, The light guide plate includes a boss structure, which is used to fix the diffuser plate, the prism sheet and the brightness enhancement film. The orthographic projections of the adhesive portion, the first adhesive layer, the second adhesive layer, and the third adhesive layer on the back plate overlap with the orthographic projections of the boss structure on the back plate.

12. The backlight module according to claim 11, characterized in that, The backlight module includes a third light-shielding layer that covers the boss structure.

13. The backlight module according to claim 11, characterized in that, The backlight module includes a fourth light-shielding layer that covers the edge region of the surface of the diffuser plate away from the back plate.

14. The backlight module according to any one of claims 3 to 10, 12, and 13, characterized in that, The orthographic projections of the second adhesive layer and the third adhesive layer on the back panel overlap, the orthographic projection of the third adhesive layer on the back panel is located within the orthographic projection of the first adhesive layer on the back panel, and the orthographic projection of the adhesive portion on the back panel is located within the orthographic projection of the second adhesive layer on the back panel.

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

Images