Backlight module and display device

Abstract

The utility model discloses a backlight module and a display device, and the backlight module comprises a light guide plate which is provided with a light-out surface and a light-in surface; the light source is arranged on one side of the light incident surface of the light guide plate; the frame is provided with a back plate and a frame protruding along the edge of the back plate, and the frame is used for containing the light guide plate and the light source; each elastic piece is provided with an elastic plate and a first protruding portion arranged on the surface of the side, close to the light guide plate, of the elastic plate, one end of each elastic plate is a fixed end connected with the frame, the other end of each elastic plate is a free end, the first protruding portions are arranged at the free ends close to the elastic plates, the number of the elastic pieces is at least two, and the first protruding portions are arranged on the surfaces of the sides, close to the light guide plate, of the elastic plates. The two first protruding parts abut against the two side faces of the light guide plate respectively. The two elastic pieces abut against the side faces of the light guide plate, the positions of the light guide plate in the two directions are limited, and the light guide plate can be allowed to expand while the light guide plate is positioned and fixed.

Description

Technical Field

[0001] The utility model relates to the field of display technology, and more specifically, to a backlight module and a display device. Background Art

[0002] Liquid Crystal Module (LCM) is widely used in mobile phones, tablets, TVs, automotive and wearable devices. LCM consists of a thin film transistor liquid crystal display (TFT LCD) and a backlight unit (BLU). The backlight unit provides the light source and mainly includes a light guide plate, a light source and a frame. The light guide plate and the frame can be connected and fixed by a connecting layer with a double-sided adhesive layer. Existing connecting layers include connecting layers formed of polyethylene terephthalate (PET), and the material of the light guide plate is usually polycarbonate (PC) or polymethyl methacrylate (PMMA). The light guide plate will expand at high temperatures, thereby squeezing the connecting layer. After long-term use, the connecting layer will age and deform, causing the connecting layer to lose its function of bonding and fixing the light guide plate, causing the light guide plate to easily move in the frame. When vibrating, the light guide plate collides with the light source and the frame, causing problems such as abnormal noise. Utility Model Content

[0003] The purpose of the utility model is to provide a backlight module and a display device, wherein the light guide plate of the backlight module can be reliably fixed in a frame and is not prone to displacement.

[0004] According to one aspect of the present invention, a backlight module is provided, comprising:

[0005] a light guide plate having a light emitting surface and a light incident surface, wherein the light incident surface is a side surface intersecting the light emitting surface and for light incident;

[0006] a light source, disposed on one side of the light incident surface of the light guide plate and having a light emitting surface for incident light toward the light incident surface;

[0007] A frame having a back plate and a frame raised along an edge of the back plate, the frame being used to accommodate the light guide plate and the light source;

[0008] An elastic member having an elastic plate and a first protrusion arranged on a surface of one side of the elastic plate close to the light guide plate, one end of the elastic plate is a fixed end connected to the frame, and the other end is a free end, the first protrusion is arranged near the free end of the elastic plate, the number of the elastic members is at least 2, and the two first protrusions respectively abut against the two side surfaces of the light guide plate.

[0009] Optionally, the frame is provided with a first avoidance opening, and the elastic member is arranged in the first avoidance opening.

[0010] Optionally, a surface of the elastic plate close to the light guide plate is flush with a surface of the frame close to the light guide plate.

[0011] Optionally, the back plate is connected to the center position of the frame, the height of the elastic plate is equal to the height of the frame, and an avoidance hole is opened at the position of the back plate corresponding to the elastic plate, and the free end of the elastic plate passes through the avoidance hole.

[0012] Optionally, the elastic plate is configured to be in a rectangular plate shape, and a fixed end of the elastic plate is connected to the frame.

[0013] Optionally, the elastic plate is configured to be in an inverted T-shape, and a fixed end of the elastic plate is connected to a surface of the back plate away from the light guide plate.

[0014] Optionally, a plurality of second protrusions are provided on the side surface of the light guide plate, and the frame is provided with limiting grooves corresponding to the second protrusions.

[0015] Optionally, a surface of the second protrusion close to the back plate is configured as an inclined surface.

[0016] Optionally, a reflective membrane is further included, and the reflective membrane is provided with a second avoidance opening corresponding to the first protrusion.

[0017] Optionally, the frame further comprises a back plate and a frame-shaped upper plastic frame, wherein the frame and the back plate are integrally formed by injection molding. The cross section of the upper plastic frame is generally L-shaped, with one side surface being in contact with the folded edge of the back plate and the other side surface being in contact with the top surface of the frame.

[0018] Optionally, it further includes a third protrusion provided on the frame and a first fixing hole at a corresponding position on the back plate, and the two are clipped together.

[0019] Optionally, it further includes a second fixing hole provided at a corresponding position of the fourth protrusion on the back plate and the upper glue frame, and the two are clamped together.

[0020] According to another aspect of the present invention, a display device is provided, comprising the above-mentioned backlight module and a display panel located on the light-emitting side of the backlight module.

[0021] The beneficial effects of the utility model are as follows:

[0022] The backlight module's two elastic members abut the sides of the light guide plate, defining the plate's position in two directions. This secures the plate while also allowing for expansion. Furthermore, the frame and backplate of the backlight module are integrally injection-molded, forming a single-piece plastic-iron frame that ensures frame strength. The frame's two sets of snap-fit structures ensure the connection strength between the frame, backplate, and upper plastic frame. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The specific implementation of the present invention will be further described in detail below with reference to the accompanying drawings.

[0024] Figure 1 The figure shows the exploded structure of the backlight module of the present invention.

[0025] Figure 2 The figure shows a structural diagram of the backlight module frame of the present invention.

[0026] Figure 3 An enlarged view of the structure of section A of the backlight module frame of the present invention is shown.

[0027] Figure 4 Shown is a top view of the backlight module frame of the present invention.

[0028] Figure 5 The BB cross-sectional view of the backlight module frame of the present invention is shown.

[0029] Figure 6 The CC cross-sectional view of the backlight module frame of the present invention is shown.

[0030] Figure 7 The figure shows the structure of the light guide plate of the backlight module of the present invention.

[0031] Figure 8 A partial structural diagram of the backlight module of the present invention is shown.

[0032] Figure 9 An enlarged view of the structure of part A of the backlight module frame and the reflective film of the present invention is shown.

[0033] Figure 10 A partial structural diagram of an embodiment of the backlight module of the present invention is shown.

[0034] Figure 11 A structural schematic diagram of the frame and back plate of the utility model is shown.

[0035] Figure 12 A structural schematic diagram of the frame, back plate and upper glue frame of the utility model is shown. DETAILED DESCRIPTION

[0036] To more clearly illustrate the present invention, the present invention is further described below in conjunction with preferred embodiments and accompanying drawings. Similar components in the accompanying drawings are represented by the same reference numerals. Those skilled in the art should understand that the following detailed description is illustrative rather than restrictive and should not be used to limit the scope of protection of the present invention.

[0037] In the description of this disclosure, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; they may refer to direct connection or indirect connection through an intermediate medium; they may refer to internal communication between two elements or interaction between two elements. Those skilled in the art will understand the specific meanings of these terms in this disclosure based on the specific circumstances.

[0038] In the disclosure, unless otherwise clearly specified and limited, a first feature being "on" or "under" a second feature may include the first and second features being in direct contact, or the first and second features not being in direct contact but being in contact via another feature therebetween.

[0039] In the description of this embodiment, terms such as "upper," "lower," "left," and "right" are used to refer to positions or locations based on the positions or locations shown in the accompanying drawings. These terms are intended solely to facilitate description and simplify operation, and are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0040] With the continuous advancement of liquid crystal display technology, the application areas of LCDs, especially color LCDs, are expanding. The backlight module (BLM) provides the light source for LCDs. LCDs themselves do not emit light, so the performance of the backlight module's light source determines the visual appearance of the display. The backlight module is composed of a stacked structure consisting of a reflective film layer, a light guide plate (LGP), a diffuser film layer, and upper and lower light-enhancing films. LED light strips are installed on one side of the LGP to achieve uniform light distribution across the entire LGP. The LGP operates by utilizing optical-grade acrylic / PC sheet material. Light guide points are printed on the underside of the optical-grade acrylic sheet using UV screen printing technology using a material with extremely high reflectivity and a non-light-absorbing property. The optical-grade acrylic sheet absorbs light from the backlight source (LED). When light from the LGP's light entrance surface strikes each light guide point, the reflected light diffuses in all directions before exiting through the LGP's light exit surface. By utilizing light guide points of varying densities and sizes, the light guide plate can emit light evenly, converting side-lighting into "surface-lighting." A reflective film layer then reflects the received light back into the light guide plate, improving light utilization efficiency. The edge-lit backlight design places LED light strips at the edge of the backplate, then uses a light guide plate to transmit light to the center of the screen, ensuring sufficient light across the entire panel. The light guide plate is a critical component of the backlight module, and the quality of its installation directly impacts the image quality of the LCD display.

[0041] Based on this, the embodiment of the present disclosure provides a backlight module, such as Figures 1 to 3 As shown, the backlight module includes a light source 10, a light guide plate 20, an optical film layer, a frame 30, and an elastic member 40. The light source 10 is configured to provide light and includes a flexible circuit board 11 and multiple backlights 12 disposed on the flexible circuit board 11. The flexible circuit board 11 includes a first surface on which the backlights 12 are disposed and a second surface opposite to the first surface. The multiple backlights 12 can be, but are not limited to, light-emitting diodes (LEDs), mini LEDs, micro LEDs, organic light-emitting diodes (OLEDs), etc., without limitation herein.

[0042] The backlight module of this embodiment is a side-entry backlight. By setting a light guide plate 20, the light emitted by the backlight lamp 12 can be refracted or reflected to the display panel and emitted as a whole. The light bar 10 is located on the side of the light incident surface of the light guide plate 20. The light guide plate 20 includes a light incident surface for the incident light source 10 to emit light, a light exit surface for emitting the light, a first reflective surface opposite to the light exit surface, and a second reflective surface connecting the first reflective surface and the light exit surface. The light exit side of the light source 10 faces the light incident surface of the light guide plate 20. Figure 1In the direction shown, the top surface of the light guide plate 20 is the light emitting surface, the bottom surface is the first reflection surface, the right side surface of the light guide plate 20 is the light incident surface, and the other side surfaces are the second reflection surfaces, that is, the side surface close to the light source 10 among the four side surfaces of the light guide plate 20 is the light incident surface, and the other three side surfaces are the second reflection surfaces.

[0043] The base material of the light guide plate 20 can be one of glass, acrylic, polycarbonate (PC for short), etc., and dots are set on the bottom surface of the base material using techniques such as laser engraving, V-shaped cross grid engraving, UV screen printing, etc. By reasonably designing the density, size, shape, etc. of the dots, the light emitted by the backlight 12 can be reflected or refracted by the dots and then evenly emitted from the top surface of the base material. The specific structure and arrangement of the dots can be designed according to product requirements, and the embodiments of the present disclosure are not limited here.

[0044] The optical film layer is arranged on the surface of the light guide plate 20, including a reflective film layer arranged on the bottom surface of the light guide plate 20, that is, the first reflective surface, and a diffusion film layer, a lower light-enhancing film layer and an upper light-enhancing film layer arranged in sequence on the top surface of the light guide plate 20, that is, the light-emitting surface. The optical film layer allows the light emitted by the backlight 12 to be evenly irradiated to the liquid crystal panel.

[0045] The frame 30 includes a back plate 31 and a frame 32 protruding along an edge of the back plate 31 . The light source 10 and the light guide plate 20 are disposed in a space formed by the frame 30 .

[0046] The elastic member 40 includes an elastic plate 41 and a first protrusion 42 disposed on a surface of the elastic plate 41 on a side proximal to the light guide plate 20. One end of the elastic plate 41 is fixed to the frame 30, and the other end is a free end. The first protrusion 42 is disposed proximal to the free end of the elastic plate 41. There are at least two elastic members 40, and the first protrusions 42 on the two elastic members 40 respectively abut against two side surfaces of the light guide plate 20.

[0047] Since the light source 10 is provided on one side of the light incident surface of the light guide plate 20, the elastic member 40 is not provided on this side, but elastic members can be provided on two of the other three sides. For example, an elastic member 40 is provided on one side relative to the light incident side of the light guide plate 20, and an elastic member 40 is provided on one of the two adjacent sides of the light incident side, so that the two elastic members 40 respectively limit the position of the light guide plate 20 in two directions.

[0048] The elastic plate 41 has a certain elastic deformation, that is, the free end of the elastic plate 41 has a certain displacement. During assembly, the light source 10 in the backlight module is positioned adjacent to the light incident surface of the light guide plate 20. The light incident surface of the light guide plate 20 contacts the frame 32. The two side surfaces of the light guide plate 20 abut against the first protrusion 42 of the elastic member 40, with a gap between these two side surfaces and the frame 32. The other side surface of the light guide plate 20 also contacts the frame. All four side surfaces of the light guide plate 20 are in contact with the outside, thereby achieving positioning and fixing of the light guide plate 20.

[0049] During use, as the light guide plate 20 absorbs heat from the external light source 10 and expands, the light incident surface and one adjacent side surface of the light guide plate 20 contact the frame 32 and become immobile. The other two surfaces of the light guide plate 20 that abut the elastic member 40 push the first protrusion 42 away from the center of the light guide plate 20, thereby driving the free end of the elastic plate 41 to move. In this structure, the first protrusion 42 of the elastic member 40 always abuts the side surface of the light guide plate 20, thereby securing the light guide plate 20 in place while also allowing it to expand.

[0050] like Figure 2 As shown, the frame 32 is provided with a first avoidance opening 321 , and the elastic member 40 is disposed in the first avoidance opening 321 , so that the elastic member 40 does not occupy additional space, ensuring that the backlight module can maintain a narrow frame.

[0051] In one example, the surface of the elastic plate 41 near the light guide plate 20 is flush with the surface of the frame 32 near the light guide plate 20, simplifying the structural design of the injection mold and allowing the elastic member 40 to be integrally injection-molded with the frame 30. When the light guide plate 20 is placed in the frame 30, the two side surfaces of the light guide plate 20 squeeze the first protrusion 42, causing the elastic plate 41 to elastically deform. In other words, before the light guide plate 20 expands due to heat, the elastic plate 41 has already been pre-deformed, thereby applying a pre-compression force to the light guide plate 20. As the light guide plate 20 expands due to heat, the elastic plate 41 can continue to deform until the light guide plate 20 reaches its maximum expansion. The elastic plate 41 can always apply a compressive force to the light guide plate 20, thereby achieving the positioning and fixation of the light guide plate.

[0052] In one example, if Figures 4-6 As shown, the edge of the back panel 31 is connected to the center position of the frame 32, that is, the back panel 31 is located in the center position of the frame 32, the height of the elastic plate 41 is equal to the height of the frame 32, and an avoidance hole 311 is opened at the position of the back panel 31 corresponding to the elastic plate 41, and the free end of the elastic plate 41 passes through the avoidance hole 311 and is located above the back panel 31.

[0053] The shape of the elastic plate 41 is set to a rectangular plate shape, and the fixed end of the elastic plate 41 is connected to the frame 32, thereby increasing the distance between the fixed end and the free end of the elastic plate 41, so that the free end of the elastic plate 41 increases the elastic deformation amount, increases the moving distance of its free end, and adapts to the expansion amount of the light guide plate 20.

[0054] like Figure 5 As shown, the shape of the elastic plate 41 can also be set to an inverted T shape, and the fixed end of the elastic plate 41 is connected to the bottom surface of the back plate 31, that is, the fixed end of the elastic plate 41 is connected to the surface of the back plate 31 away from the light guide plate 20.

[0055] In one example, the surface of the first protrusion 42 away from the light guide plate 20 is set as an inclined surface, so that when the light guide plate 20 is assembled, it is convenient for the light guide plate 20 to slide along the inclined surface and make the first protrusion 42 abut against the side of the light guide plate 20.

[0056] like Figure 1 、 Figure 7 and Figure 8 As shown, the side of the light guide plate 20 is provided with multiple second protrusions 21, that is, multiple second protrusions 21 are respectively provided on at least two side surfaces of the light guide plate 20. In this embodiment, the light guide plate 20 has three second protrusions 21, one on each of two opposing side surfaces of the light guide plate 20. That is, one second protrusion 21 is provided on one side surface of the light guide plate 20, and two second protrusions 21 are provided on the other opposing side surface. The corresponding frame 32 is provided with multiple retaining grooves 322, with each second protrusion 21 corresponding to each retaining groove 322. When the light guide plate 20 and the frame 30 are assembled, the second protrusions 21 are located within the retaining grooves 322, forming a snap-fit structure that prevents the light guide plate 20 from separating from the frame 30 in the thickness direction. The engagement of the second protrusions 21 on both sides of the light guide plate 20 with the retaining grooves 322 on the frame 32 prevents the light guide plate 20 from separating from the frame 30, thereby securing the light guide plate 20 to the frame 30 in the thickness direction. The second protrusions 21 are disposed on two opposite side surfaces of the light guide plate 20 , that is, the second protrusions 21 are disposed on both side surfaces adjacent to the light incident surface of the light guide plate 20 .

[0057] In one example, the length b of the second protrusion 21 within the limiting groove 322 ranges from 0.2 mm to 0.3 mm, preferably 0.25 mm. The gap c between the surface of the second protrusion 21 away from the back plate 31 and the limiting groove 322 ranges from 0.2 mm to 0.3 mm, preferably 0.1 mm. To facilitate smoother assembly of the light guide plate 20, the surface of the second protrusion 21 adjacent to the back plate 31 is configured as an inclined surface.

[0058] like Figure 8 As shown, the frame 30 also includes a back plate 33. The back plate 33 of the embodiment of the present disclosure is made of a stainless steel plate using a stamping process, and then the frame 32 and the back plate 33 are injection molded into one piece using an injection molding process, thereby forming a frame 30 that is integrated with glue and iron. Embedding metal parts into the frame 32 can effectively improve the problems of warping and deformation of the frame 32, and ensure the strength of the frame 32. The folding edge of the back plate 33 adopts a conventional stamping die folding edge, maintaining a 90° angle with the back plate, and the folding edge height is adjusted according to the thickness of the specific project laminate. The frame 32 is arranged on the side of the metal folding edge close to the light guide plate 20, so that the frame 32 can contact the light guide plate 20.

[0059] like Figure 10 and Figure 11 As shown, a plurality of third protrusions 323 are provided on the surface of the frame 32 near the folded edge of the back panel 33, and a plurality of first fixing holes 331 are provided on the back panel 33 corresponding to the third protrusions 323. By engaging the third protrusions 323 in the first fixing holes 331, the connection between the third protrusions 323 and the first fixing holes 331 is achieved, thereby further improving the connection strength between the frame 32 and the back panel 33. Preferably, the third protrusions 323 can be provided on one side or multiple sides of the frame 32 to achieve a fixed connection between one or more sides of the frame 32 and the back panel 33. For example, there are three third protrusions 323, each located on two adjacent sides of the frame 32, that is, one third protrusion 323 is provided on one side of the frame 32, and two third protrusions 323 are provided on the other side.

[0060] like Figure 10 and Figure 12 As shown, the frame 30 also includes a frame-shaped upper glue frame 34. The upper glue frame 34 has a generally L-shaped cross-section, with one side surface of the upper glue frame 34 being in contact with the folded edge of the back panel 33, and the other side surface being in contact with the top surface of the frame 32. A plurality of fourth protrusions 332 are provided on the surface of the folded edge of the back panel 33 near the upper glue frame 34. The upper glue frame 34 is provided with a plurality of second fixing holes 341 corresponding to the fourth protrusions 332. By engaging the fourth protrusions 332 with the second fixing holes 341, the fourth protrusions 332 and the second fixing holes 341 are fixedly connected, thereby achieving a fixed connection between the back panel 33 and the upper glue frame 34.

[0061] In one example, each of the four folded edges of the back panel 33 is provided with at least one fourth protrusion 332, and correspondingly, each of the four side edges of the upper rubber frame 34 is provided with a second fixing hole 341. It is understood that the number of fourth protrusions 332 provided on each folded edge of the back panel 33 may be equal or unequal, and those skilled in the art may design the same based on actual product requirements.

[0062] In one example, the fourth protrusion 332 is in the shape of a semi-cone and is located at the upper edge of the first fixing hole 331 . The two are adjacent to each other, which facilitates mold design and can be formed in one step using a stamping process.

[0063] In one example, if Figure 9 As shown, the backlight module also includes a reflective film 22, which is disposed between the light guide plate 20 and the back plate 31. Specifically, the reflective film 22 is disposed on the first reflective surface of the light guide plate 20 to reflect light into the light guide plate 20, thereby improving the utilization rate of the light source 10. The reflective film 22 has a second avoidance opening 221 corresponding to the first protrusion 42. This prevents the first protrusion 42 from interfering with the reflective film 22 when the reflective film 22 is assembled into the frame 30. To prevent interference between the elastic member 40 and the reflective film 22, a gap is provided between the second avoidance opening 221 and the elastic member 40, preferably with a gap value of 0.05 mm.

[0064] An embodiment of the present invention also provides a display device, which includes a backlight module as described in the above embodiment and a display panel located on the light-emitting side of the backlight module. The display device can have all the features and effects of the above backlight module, which will not be repeated here.

[0065] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the scope of protection of the present invention.

Claims

1. A backlight module, characterized in that: include: a light guide plate having a light emitting surface and a light incident surface, wherein the light incident surface is a side surface intersecting the light emitting surface and for light incident; a light source, disposed on one side of the light incident surface of the light guide plate and having a light emitting surface for incident light toward the light incident surface; A frame having a back plate and a frame raised along an edge of the back plate, the frame being used to accommodate the light guide plate and the light source; An elastic member having an elastic plate and a first protrusion arranged on a surface of one side of the elastic plate close to the light guide plate, one end of the elastic plate is a fixed end connected to the frame, and the other end is a free end, the first protrusion is arranged near the free end of the elastic plate, the number of the elastic members is at least 2, and the two first protrusions respectively abut against the two side surfaces of the light guide plate.

2. The backlight module according to claim 1, wherein: The frame is provided with a first avoidance opening, and the elastic member is arranged in the first avoidance opening.

3. The backlight module according to claim 2, wherein: A surface of the elastic plate close to the light guide plate is flush with a surface of the frame close to the light guide plate.

4. The backlight module according to claim 3, wherein: The back plate is connected to the center of the frame, the height of the elastic plate is equal to that of the frame, and a circumvention hole is provided on the back plate at a position corresponding to the elastic plate, and the free end of the elastic plate passes through the circumvention hole.

5. The backlight module according to claim 4, wherein: The elastic plate is configured to be in a rectangular plate shape, and a fixed end of the elastic plate is connected to the frame.

6. The backlight module according to claim 4, wherein: The elastic plate is configured in an inverted T shape, and a fixed end of the elastic plate is connected to a surface of the back plate away from the light guide plate.

7. The backlight module according to claim 1, wherein: A plurality of second protrusions are provided on the side surface of the light guide plate, and a limiting groove corresponding to the second protrusions is formed on the frame.

8. The backlight module according to claim 7, wherein: The surface of the second protrusion close to the back plate is configured as an inclined surface.

9. The backlight module according to claim 1, wherein: It also includes a reflective film, and the reflective film is provided with a second avoidance opening corresponding to the first protrusion.

10. A display device, characterized in that: It comprises the backlight module according to any one of claims 1 to 9, and a display panel located on the light-emitting side of the backlight module.

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