Backlight module and display device

Abstract

The embodiment of the present invention discloses a backlight module and a display device, comprising: a back plate, a rubber frame, a light bar and a light guide plate; the back plate comprises a bottom plate and a side plate located around the bottom plate, the bottom plate and the side plate form a receiving cavity; the light guide plate and the light bar are located in the receiving cavity, the rubber frame surrounds the light guide plate and is arranged in the receiving cavity; the light bar is arranged on the side where the light incident surface of the light guide plate is located, and the light bar is located between the light guide plate and the side plate; wherein the light guide plate comprises a limiting portion, the limiting portion is located at a corner of the light guide plate on a side close to the light bar; the rubber frame comprises a buffer structure arranged in correspondence with the limiting portion of the light guide plate, the buffer structure is configured to contact with the limiting portion in case of a collision to play a buffering role; the connection between the bottom plate and the side plate comprises a buffer fillet, the buffer fillet is located at the transition between the bottom plate and the side plate, the buffer fillet is configured to contact with the light bar in case of a collision to play a buffering role.

Description

Technical Field

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

[0002] Thin film transistor liquid crystal display screens have many advantages such as thin body, power saving, and no radiation, and have been widely used. Handheld tablet computers have developed rapidly under this background, and are currently developing rapidly in the direction of ultra-thin, ultra-light, and ultra-narrow bezels. This has brought more and more challenges to backlight design. Taking the backlight side design as an example, the narrow bezel means that after the LED on the light bar side is hit, its distance from the root of the U-fold is getting smaller and smaller. At present, the welding area at the general LED pin is small, and the push-pull force test specification is usually 0.8kg. With the increasing design requirements for ultra-narrow bezels of the whole machine, more and more whole machine tests have LEDs falling off during the drop test, causing a single string of LEDs to not light up, that is, dead light. In order to improve the dead light, the usual design is to apply red glue (epoxy resin) directly below the LED before LED welding, that is, before printing solder paste, first print red glue through the steel screen, then print solder paste, after patching, and finally reflow soldering to ensure that the solder paste and LED pins are cured and effective at the same time, but this solution will increase production costs. Summary of the invention

[0003] In view of the above problems, an object of the present invention is to provide a backlight module capable of improving the problem of dead lamps in a drop test.

[0004] Another object of the present invention is to provide a display device including the above-mentioned backlight module.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] According to one aspect of the present invention, there is provided a backlight module, comprising:

[0007] Back panel, plastic frame, light bar and light guide plate;

[0008] The back plate includes a bottom plate and side plates located around the bottom plate, and the bottom plate and the side plates form a receiving cavity;

[0009] The light guide plate and the light bar are located in the accommodating cavity, and the plastic frame is located on a side of the side plate close to the light guide plate;

[0010] The light bar is arranged on the side where the light incident surface of the light guide plate is located, and the light bar is located between the light guide plate and the side plate;

[0011] Wherein, the light guide plate comprises a limiting portion, and the limiting portion is located at a corner of a side of the light guide plate close to the light bar;

[0012] The plastic frame includes a buffer structure arranged to correspond to the limiting portion of the light guide plate, and the buffer structure is configured to contact the limiting portion to play a buffering role when a collision occurs;

[0013] The connection between the bottom plate and the side plate includes a buffer fillet, which is located at the transition between the bottom plate and the side plate. The buffer fillet is configured to contact the light bar to play a buffering role when a collision occurs.

[0014] In addition, a preferred solution is that the side plate includes a bent portion located on a side of the bottom plate close to the light incident surface of the light guide plate, and the light bar is located between the light guide plate and the bent portion;

[0015] The plastic frame includes a first frame and a second frame which are arranged on two opposite sides of the light guide plate, and a third frame which is located on a side of the light guide plate away from the bending portion;

[0016] The first frame and the second frame are respectively located at two ends of the third frame.

[0017] In addition, a preferred solution is that the buffer structure is located at an end of the first frame away from the third frame;

[0018] The buffer structure includes a bevel portion corresponding to the limiting portion and a boss portion extending from the bevel portion toward the second frame;

[0019] When a drop test is performed, the inner side surface of the boss portion can abut against the light incident surface of the light guide plate to avoid direct collision between the light bar and the transition between the bent portion and the bottom plate.

[0020] In addition, a preferred solution is that the distance between the light incident surface of the light guide plate and the inner side surface of the boss portion is smaller than the distance between the light bar and the inner wall of the bending portion.

[0021] In addition, a preferred solution is that the bending portion is formed by bending the bottom plate upward, and the buffer fillet is located at the transition between the bending portion and the bottom plate.

[0022] In addition, a preferred solution is that the buffer fillet is located on a side of the bending portion close to the light bar, and the radius of the buffer fillet is 0.15 mm.

[0023] In addition, a preferred solution is that the transition between the bottom plate and the bent portion includes a rounded corner, and the rounded corner is located on a side of the bent portion away from the light bar;

[0024] The radius of the bending fillet is 0.35 mm.

[0025] In addition, a preferred solution is that the length of the boss portion is greater than 0.75 mm.

[0026] In addition, a preferred solution is that the light bar includes a strip-shaped flexible circuit board and a plurality of light sources electrically connected to the strip-shaped flexible circuit board;

[0027] The light bar is arranged on at least one side of the light guide plate.

[0028] In addition, a preferred solution is that the light bar is encapsulated on the bottom plate by curing glue;

[0029] The light bar is located on any one side of the bottom plate or is arranged on multiple sides of the bottom plate;

[0030] The curing glue forms the glue frame.

[0031] In addition, a preferred solution is that the light bar includes an insulating film covering the surface of the back panel, a wiring layer formed on the surface of the insulating film, and a light source connected to the wiring layer.

[0032] According to another aspect of the present invention, there is provided a display device, comprising the above-mentioned backlight module; and

[0033] A display panel is arranged on the light emitting side of the backlight module.

[0034] The beneficial effects of the present invention are as follows:

[0035] In view of the technical problems existing in the prior art, the embodiments of the present application provide a backlight module and a display device. By setting a buffer structure corresponding to the light guide plate on the rubber frame, and designing the distance between the side where the light incident surface of the light guide plate is located and the inner side of the boss portion to be smaller than the distance between the light bar and the inner wall of the first bending portion, when performing a drop test or when the backlight module falls and bumps, the limiting portion of the light guide plate can first contact the buffer structure of the rubber frame, rather than the light bar directly colliding with the side panel, so that the impact force of the fall is released by the light guide plate, avoiding the light bar being directly impacted and causing a dead light. At the same time, a buffer fillet is also provided at the transition between the bottom plate and the bending portion, so that at the moment the whole machine falls, the end of the light bar away from the light guide plate does not directly hit the first bending portion, but moves up along the arc of the transition fillet, playing a buffering role, avoiding the LED from falling off due to direct impact. In addition, by encapsulating the light bar on the back panel with curing glue, not only the risk of bad lights caused by the light bar colliding with the back panel during the drop test or when the backlight module falls and bumps, but also the multi-sided installation of the light bar can be realized, and the traditional glue frame and bending part can be replaced to save the side space. The display panel is directly mounted on the frame formed by the UV curing glue with a certain elasticity. Its buffering performance is better than the traditional glue frame, which can improve the shock resistance of the whole machine when it falls. It effectively improves the problem of bad lights caused by LED falling off in the whole machine test. The light bar is encapsulated on the back panel with curing glue to replace the traditional glue frame, which overcomes the shortcomings of the narrow frame product that the glue frame is difficult to shape or easy to deform due to size reasons. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings.

[0037] Figure 1 A schematic structural diagram of a backlight module provided by an embodiment of the present invention is shown.

[0038] Figure 2 A schematic diagram showing the positional relationship between the buffer structure and the light guide plate provided in an embodiment of the present invention is shown.

[0039] Figure 3 A structural schematic diagram showing a partial cross section of a backlight module provided by an embodiment of the present invention.

[0040] Figure 4 A schematic diagram showing the structure of a curing adhesive replacing an adhesive frame provided by an embodiment of the present invention is shown.

[0041] Figure 5 A schematic diagram showing the distribution of the light bars provided in the first embodiment on the back panel is shown.

[0042] Figure 6 A schematic diagram showing the distribution of the light bars provided in the second embodiment on the back panel is shown.

[0043] Figure 7 A schematic diagram showing the distribution of the light bars provided in the third embodiment on the back panel is shown. DETAILED DESCRIPTION

[0044] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0045] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] In the present invention, unless otherwise clearly stipulated and limited, a first feature being “on” or “under” a second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them.

[0047] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0048] Thin film transistor liquid crystal display screens have many advantages such as thin body, power saving, and no radiation, and have been widely used. Handheld tablet computers have developed rapidly under this background, and are currently developing rapidly in the direction of ultra-thin, ultra-light, and ultra-narrow bezels. This has brought more and more challenges to backlight design. Taking the backlight side design as an example, the narrow bezel means that after the LED on the light bar side is hit, its distance from the root of the U-fold is getting smaller and smaller. At present, the welding area at the general LED pin is small, and the push-pull force test specification is usually 0.8kg. With the increasing design requirements for ultra-narrow bezels of the whole machine, more and more whole machine tests have LEDs falling off during the drop test, causing a single string of LEDs to not light up, that is, dead light. In order to improve the dead light, the usual design is to apply red glue (epoxy resin) directly below the LED before LED welding, that is, before printing solder paste, first print red glue through the steel screen, then print solder paste, after patching, and finally reflow soldering to ensure that the solder paste and LED pins are cured and effective at the same time, but this solution will increase production costs.

[0049] Combination Figure 1-4 As shown, an embodiment of the present invention provides a backlight module, which includes: a back plate 1, a plastic frame 2, a light bar 3 and a light guide plate 4. The back plate 1 includes a bottom plate 11 and side plates located around the bottom plate 11, and the bottom plate 11 and the side plates form a receiving cavity. The light guide plate 4 and the light bar 3 are located in the receiving cavity, and the plastic frame 2 is an inner frame of the backlight module, surrounding the light guide plate 4 and arranged in the receiving cavity.

[0050] In this embodiment, the light bar 3 is located on the light incident surface of the light guide plate 4 (eg Figure 3 The side where the light guide plate 4 is located, the light incident surface of the light guide plate 4 and the light exit surface of the light guide plate (such as Figure 3 The light bar 3 is located between the light guide plate 4 and the side plate, and the light bar 3 includes a strip-shaped base and a plurality of LED chips spaced apart along the extending direction of the strip-shaped base.

[0051] In one embodiment, the side panel includes a bending portion 12 located on the side of the bottom plate 11 close to the light incident surface of the light guide plate 4. The bending portion 12 is a so-called U-bend portion, including a first bending portion 121 formed by bending the bottom plate 11 upward and a second bending portion 122 formed by bending one end of the first bending portion 121 away from the bottom plate 11 toward the inner side of the accommodating cavity. The second bending portion 122 can provide support for the display panel and also shield the light mixing area of ​​the light guide plate 4. Figure 3 As shown, the projection of the bending portion 12 in the XZ plane is U-shaped.

[0052] In this embodiment, the light bar 3 is located between the light guide plate 4 and the bend 12, specifically, the light bar 3 is located between the light guide plate 4 and the first bend 121. When performing a drop test or when the backlight module falls or bumps, the light bar 3 will hit the bend 12, and the edge of the light bar 3 will collide with the root of the first bend 121, causing the LED on the light bar 3 to fall off, resulting in a dead light, which affects the yield of the backlight module. To avoid this risk, a buffer fillet 6 is processed at the transition between the bottom plate 11 and the first bend 121. When performing a drop test or when the backlight module falls or bumps, the edge of the light bar 3 will not directly collide with the root of the first bend 121, but will move up along the buffer fillet 6 to play a buffering role, thereby preventing the impact of a direct collision from causing the LED of the light bar 3 to fall off.

[0053] In this embodiment, the light guide plate 4 is a rectangular light guide plate, and the light guide plate 4 includes a limiting portion 41, which is located at a corner of the light guide plate 4 close to the light bar 3, and is used to realize the installation and positioning of the light guide plate 4 on the back plate 1. The light guide plate 4 is generally provided with one or two limiting portions 41, which need to be designed according to the structure of the back plate 1 in the actual production process.

[0054] The rubber frame 2 includes a buffer structure corresponding to the limiting portion 41 of the light guide plate 4. When a drop test is performed or when the backlight module falls and bumps, the limiting portion 41 of the light guide plate 4 can first contact the buffer structure of the rubber frame 2 instead of the light bar 3 directly colliding with the side panel. The impact force of the fall is released by the light guide plate 4, thereby preventing the light bar 3 from being directly impacted and causing a dead light.

[0055] In a specific embodiment, Figure 1 As shown, the plastic frame 2 includes a first frame 21 and a second frame 22 arranged on two opposite sides of the light guide plate 4, and a third frame 23 located on the side of the light guide plate 4 away from the bending portion 12. The first frame 21 and the second frame 22 are respectively located at two ends of the third frame 23.

[0056] In this embodiment, if Figure 1As shown, the buffer structure is located at one end of the first frame 21 away from the third frame 23. Specifically, the buffer structure includes a bevel portion 51 arranged corresponding to the limiting portion 41 of the light guide plate 4 and a boss portion 52 formed by extending the bevel portion 51 in a direction close to the second frame 22. The bevel portion 51 and the limiting portion 41 have the same inclination. The distance between the boss portion 52 and the light guide plate 4 is d. When performing a drop test, the light guide plate 4 falls, and the inner side surface of the boss portion 52 can abut against the side surface where the light incident surface of the light guide plate 4 is located, so that the light guide plate 4 contacts the rubber frame 2 first, releasing the impact force of the light guide plate 4 falling, and preventing the light bar 3 from directly hitting the first bending portion 121, causing the LED of the light bar 3 to be directly impacted, resulting in a dead light defect.

[0057] In this embodiment, in order to ensure that the light guide plate 4 contacts the plastic frame 2 first, rather than the light bar 3 hitting the root of the first bending portion 121 first, as shown in FIG. Figure 2 As shown, it is necessary to ensure that the distance d between the side surface where the light incident surface of the light guide plate 4 is located and the inner side surface of the boss portion 52 is smaller than the distance D between the light bar 3 and the inner wall of the first bending portion 121 .

[0058] Specifically, the length L of the boss portion 52 needs to be above 0.75 mm, at this time, Dd = 0.2 mm. In other embodiments, under the premise of ensuring that the expansion space of the rubber frame 2 is sufficient, the boss portion 52 may not be made, and only the bevel portion 51 may be used as a buffer structure, which can also achieve the effect of avoiding the bad dead light. For example, when the size of the limiting portion 41 of the light guide plate 4 is large, it may sometimes lead to insufficient processing space for the boss portion 52 or the length L of the boss portion 52 is within 0.75 mm. At this time, it is too difficult to process the boss portion 52. Then, you can choose not to process the boss portion 52, and only use the bevel portion 51 to limit the light guide plate 4. It is necessary to ensure that the gap e between the limiting portion 41 and the bevel portion 51 is smaller than the distance D between the light bar 3 and the inner wall of the first bending portion 121, so that the light guide plate 4 contacts the rubber frame 2 first, instead of the light bar 3 hitting the root of the first bending portion 121 first, to avoid the occurrence of the bad dead light phenomenon.

[0059] In one embodiment, Figure 3As shown, the connection between the bottom plate 11 and the side plate includes a buffer fillet 6, and the buffer fillet 6 is located at the transition between the bottom plate 11 and the side plate. The buffer fillet 6 can contact the end of the light bar 3 away from the light guide plate 4 to play a buffering role when the whole machine falls. Specifically, the buffer fillet 6 is located at the transition connection between the first bend 121 and the bottom plate 11. At the moment the whole machine falls, when the LED on the light bar 3 is impacted, the end of the light bar 3 away from the light guide plate 4 directly collides with the root of the first bend 121, which will cause the LED to fall off and form a dead light. Therefore, the buffer fillet 6 is processed at the transition between the first bend 121 and the bottom plate 11, so that at the moment the whole machine falls, the end of the light bar 3 away from the light guide plate 4 does not directly hit the first bend 121, but moves up along the arc of the transition fillet 6, which plays a buffering role and avoids the LED from falling off due to direct impact.

[0060] In this embodiment, the buffer fillet 6 is located on the inner side of the bending portion 12, that is, the side of the first bending portion 121 close to the light bar 3. In this embodiment, the radius of the buffer fillet 6 is 0.15 mm, so that when the whole machine falls and the light bar 3 is impacted, the edge of the light bar 3 does not directly hit the bending portion 12, but makes full use of the buffer fillet 6 located on the side of the first bending portion 121 close to the light bar 3. After the impact, the edge of the light bar 3 moves up along the buffer fillet 6, which plays a buffering role and prevents the light bar 3 from directly hitting the bending portion 12 and causing the LED to fall off.

[0061] In this embodiment, a bend fillet 7 is included at the transition between the bottom plate 11 and the bend portion 12 . The bend fillet 7 is located on a side of the first bend portion 121 away from the light bar 3 . The radius of the bend fillet 7 is 0.35 mm.

[0062] In one embodiment, Figure 3 As shown, the light bar 3 includes: a strip-shaped flexible circuit board 31 and a plurality of light sources 32 electrically connected to the strip-shaped flexible circuit board 31, and the light sources 32 are LEDs. The surface of the strip-shaped flexible circuit board 31 facing the lower surface of the light guide plate 4 is bonded to the lower surface of the light guide plate 4. In this embodiment, the light bar 3 can be arranged on any side of the light guide plate 4 or on multiple sides as needed to solve the problem that the light bar 3 is concentrated on one side, resulting in dense LEDs and high heat generation, causing the display panel to turn blue due to the influence of temperature.

[0063] In one embodiment, the light bar 3 is encapsulated on the bottom plate 11 by curing glue 8. The light bar 3 can be arranged on one side or multiple sides as needed, which can further avoid the light bar 3 colliding with the back plate 1 and causing a bad light. Figure 4As shown, transparent UV curing glue 8 is used to encapsulate the light bar 3 on the bottom plate 11, replacing the existing glue frame 2, and the bending portion 12 can be omitted, which not only solves the impact of the bending portion 12 on the assembly when the light bar 3 is arranged on multiple sides in the prior art, but also overcomes the shortcomings of the narrow frame product that the glue frame is difficult to shape or easy to deform due to size reasons. In other embodiments, semi-cured acrylic or PET and other plastics can also be used to encapsulate the light bar on the bottom plate 11 to replace the glue frame, thereby saving side space and further narrowing the frame.

[0064] In this embodiment, the light bar 3 is encapsulated on the bottom plate 11 by UV curing glue 8, and the bending part 12 can be omitted. The display panel is directly mounted on the frame formed by the UV curing glue with a certain elasticity. Its buffering performance is better than that of the traditional glue frame, which can improve the shock resistance of the whole machine when it falls. Because the UV curing glue has a certain elasticity, when the light guide plate 4 expands, it will compress the glue frame formed by the UV curing glue. While ensuring the shaking range of the light guide plate 4, it reserves enough expansion space to avoid the occurrence of wrinkles and other phenomena caused by the limited expansion of the light guide plate 4. In addition, after the UV curing glue is cured, it will be used as a glue frame without generating foreign matter such as debris, which is conducive to reducing foreign matter, white spots and other defects.

[0065] In the present embodiment, the UV curing glue 8 is cured on the back panel 1 to form the glue frame for mounting the display panel. At the same time, the UV curing glue 8 can also encapsulate the light bar 3 on the bottom panel 11 to realize the installation and fixation of the light bar 3 on the back panel 1, and at the same time, it can avoid direct collision between the light bar 3 and the bending transition of the bottom panel 11 and the side panel, causing the LED to fall off and resulting in poor dead light. The light bar 3 can be arranged on any side of the back panel 1, and the side of the light guide plate 4 corresponding to the light bar 3 is the light incident surface of the light guide plate 4. The remaining three sides of the back panel 1 where the light bar 3 is not set are directly cured by UV curing glue 8 to form the glue frame, and the formed glue frames are all set on the side of the side panel close to the light guide plate 4; in other embodiments, the light bar 3 can be set on multiple sides of the bottom panel 11. In embodiment one, as Figure 5 As shown, the light bar 3 can be arranged on the four sides of the back plate 1, and encapsulated on the bottom plate 11 by UV curing glue 8, and the traditional glue frame is replaced by UV curing glue 8 to carry the display panel; in the second embodiment, as shown Figure 6 As shown, the light bar 3 can also be arranged on any two sides of the back plate 1, and encapsulated on the bottom plate 11 by UV curing glue 8. The other two sides of the back plate 1 without the light bar 3 are directly cured by UV curing glue 8 to form the glue frame. The formed glue frame is arranged on the side of the side plate close to the light guide plate 4 for carrying the display panel. In the third embodiment, as shown in FIG. Figure 7As shown, the light bar 3 can also be arranged on any three sides of the back plate 1, and encapsulated on the bottom plate 11 by UV curing glue 8. The remaining sides of the back plate 1 without the light bar 3 are directly cured by UV curing glue 8 to form the glue frame. The formed glue frames are all arranged on the side of the side plate close to the light guide plate 4, which is used to carry the display panel. The multi-sided installation of the light bar 3 on the back plate 1 can solve the problem that the light bar 3 is concentrated on one side, resulting in dense LEDs and high heat generation, causing the display panel to turn blue due to the temperature. The above three embodiments are only described as examples. In the actual production process, those skilled in the art can design the installation of the light bar 3 according to actual needs, and this embodiment does not make specific restrictions on this.

[0066] In this embodiment, the light bar 3 is attached to the back plate 1. Specifically, the light bar 3 includes: a strip-shaped flexible circuit board 31 and a plurality of light sources 32 electrically connected to the strip-shaped flexible circuit board 31. The surface of the strip-shaped flexible circuit board 31 facing the lower surface of the light guide plate 4 is bonded to the lower surface of the light guide plate 4. In other embodiments, the light bar 3 can also be installed on the back plate 1 by directly punching it onto the back plate 1. Specifically, the light bar 3 includes an insulating film (not shown) covering the surface of the bottom plate 11 and a wiring layer (not shown) formed on the surface of the insulating film by processes such as coating and etching, and an LED light source is connected to the wiring layer.

[0067] In one embodiment, the curing glue 8 is cured on the back panel 1 by transfer printing, and the light bar 3 is encapsulated on the back panel 1. Specifically, a process similar to prism manufacturing is adopted, using a roller or APR plate, while injecting glue and roller printing, and irradiating ultraviolet light to cure, to form a glue frame. In another embodiment, a mold injection process is adopted, using a mold similar to the glue-iron integrated process, using a transparent material, after the glue is injected into the cavities that need to be injected, ultraviolet light is used to irradiate the transparent mold and cure the glue to obtain a glue frame made of UV-curing glue.

[0068] Another embodiment of the present invention provides a display device, the backlight module in the above embodiment, a display panel arranged on the light-emitting side of the backlight module, an optical film layer arranged on the side of the light guide plate away from the bottom plate 11, and a reflective sheet arranged between the light guide plate 4 and the bottom plate 11 of the back plate 1. Specifically, the display device can be any product or component with a display function, such as a liquid crystal display panel, electronic paper, a mobile phone, a tablet computer, a television, a monitor, a laptop computer, a digital photo frame, a navigator, etc.

[0069] In this embodiment, the display panel, the optical film layer, the light guide plate 4 and the reflector are all in the form of flat sheets, and the display panel, the optical film layer, the light guide plate 4, the reflector and the back plate 1 are stacked in parallel or substantially in parallel. The size of the optical film layer should be slightly larger than the size of the light guide plate 4 and the reflector, so that when the optical film layer is stacked in sequence with the light guide plate 4 and the reflector, at least part of the outer edge of the optical film layer can extend beyond the edge of the light guide plate 4 and the reflector. The back plate 1 is preferably made of a solid hard material such as metal or hard plastic to provide support and protection in the overall structure. The reflector is preferably a film or thin layer made of a high reflectivity material, for example, a film made of a high reflectivity polymer material, or a uniform coating formed by coating a high reflectivity metal material on the back plate 1; in the reflector, at least one surface facing away from the back plate 1 is a reflective surface with extremely high reflectivity and a mirror effect, and the light reaching the reflective surface will be fully reflected back to the inside of the display panel, which helps to provide a high-efficiency backlight for the display panel. The light guide plate 4 can be made by combining an optical grade acrylic sheet with a light guide point made of a high reflectivity material. When the light emitted by the light source arranged around the light guide plate 4 enters the light guide plate 4 from the side of the light guide plate 4, the light guide plate 4 can change the propagation direction of these light rays, so that these light rays are emitted from the light guide plate 4 toward the surface inside the display device (that is, toward the surface of the optical film layer), providing backlight for the display panel. The optical film layer is stacked on the lower surface of the display panel to improve the backlight effect of the display panel; in this embodiment, the optical film layer is preferably a lower diffuser, a lower prism sheet, an upper prism sheet, and an upper diffuser, which are stacked in sequence from bottom to top. In other embodiments, the optical film layer is a polarizing film, which can control the polarization of the light emitted from the light guide plate 4 based on its own material and structure, and only allow light with a predetermined polarization angle to pass through. Therefore, after the light emitted from the light guide plate 4 passes through the optical film layer, its polarization angle will be adjusted to an ideal range suitable for the display panel; or according to specific needs, the optical film layer can also be an anti-reflection film for improving the brightness of the light, a diffusion film for improving the uniformity of the light, a filter film for filtering out stray colored light, etc. The display panel is provided with a liquid crystal layer and a color filter, wherein the liquid crystal molecules in the liquid crystal layer will produce a specific light and dark distribution under the action of an external voltage, and the light transmitted from the optical film layer will produce corresponding colored light after passing through the color filter, and the colored light is transmitted through the liquid crystal layer with a specific light and dark distribution, so that a color image can be formed on the outer surface of the display panel.

[0070] The backlight module and display device provided by the embodiment of the present invention, by providing a buffer structure on the rubber frame 2, and designing the distance between the side where the light incident surface of the light guide plate 4 is located and the inner side of the boss portion 52 to be smaller than the distance between the light bar 3 and the inner wall of the first bent portion 121, can make the limiting portion 41 of the light guide plate 4 contact the buffer structure of the rubber frame 2 first when performing a drop test or when the backlight module falls and bumps, instead of the light bar 3 directly hitting the side panel, so that the impact force of the fall is released by the light guide plate 4, avoiding the light bar 3 from being directly impacted and causing a dead light. At the same time, a buffer fillet 6 is also provided at the transition between the bottom plate 11 and the bent portion 12, so that at the moment of the whole machine falling, the end of the light bar 3 away from the light guide plate 4 does not directly hit the first bent portion 121, but moves up along the arc of the transition fillet 6, playing a buffering role, avoiding the direct impact and causing the LED to fall off. In addition, the light bar 3 is encapsulated on the back plate 1 by curing glue 7, which not only reduces the risk of bad lights caused by the light bar 3 colliding with the back plate 1 during the drop test or when the backlight module falls and bumps, but also realizes the multilateral installation of the light bar 3, and can also replace the traditional glue frame and bending part, saving side space. The display panel is directly mounted on the frame formed by the UV curing glue with a certain elasticity. Its buffering performance is better than the traditional glue frame, which can improve the shock resistance of the whole machine when it falls. It effectively improves the problem of bad lights caused by LED falling off during the whole machine test. The light bar is encapsulated on the back plate 1 by curing glue, replacing the traditional glue frame, and overcomes the shortcomings of narrow frame products that the glue frame is difficult to shape or easy to deform due to size reasons.

[0071] 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 protection scope of the present invention.

Claims

1. A backlight module, characterized in that: include: Back panel, plastic frame, light bar and light guide plate; The back plate includes a bottom plate and side plates located around the bottom plate, and the bottom plate and the side plates form a receiving cavity; The light guide plate and the light bar are located in the accommodating cavity, and the plastic frame is located on a side of the side plate close to the light guide plate; The light bar is arranged on the side where the light incident surface of the light guide plate is located, and the light bar is located between the light guide plate and the side plate; Wherein, the light guide plate comprises a limiting portion, and the limiting portion is located at a corner of a side of the light guide plate close to the light bar; The plastic frame includes a buffer structure arranged corresponding to the limiting portion of the light guide plate, and the buffer structure is configured to contact the limiting portion to play a buffering role when a collision occurs; The connection between the bottom plate and the side plate includes a buffer fillet, the buffer fillet is located at the transition between the bottom plate and the side plate, and the buffer fillet is configured to contact the light bar to play a buffering role when a collision occurs; The light bar is encapsulated on the bottom plate by curing glue; The light bar is located on any one side of the bottom plate or is arranged on multiple sides of the bottom plate; The curing adhesive forms the adhesive frame.

2. The backlight module according to claim 1, characterized in that: The side plate comprises a bent portion located on a side of the bottom plate close to the light incident surface of the light guide plate, and the light bar is located between the light guide plate and the bent portion; The plastic frame includes a first frame and a second frame which are arranged on two opposite sides of the light guide plate, and a third frame which is located on a side of the light guide plate away from the bending portion; The first frame and the second frame are respectively located at two ends of the third frame.

3. The backlight module according to claim 2, characterized in that: The buffer structure is located at an end of the first frame away from the third frame; The buffer structure includes a bevel portion corresponding to the limiting portion and a boss portion extending from the bevel portion toward the second frame; When a drop test is performed, the inner side surface of the boss portion can abut against the light incident surface of the light guide plate to avoid direct collision between the light bar and the transition between the bent portion and the bottom plate.

4. The backlight module according to claim 3, characterized in that: The distance between the light incident surface of the light guide plate and the inner side surface of the boss portion is smaller than the distance between the light bar and the inner wall of the bending portion.

5. The backlight module according to claim 2, characterized in that: The bending portion is formed by bending the bottom plate upward, and the buffer fillet is located at the transition between the bending portion and the bottom plate.

6. The backlight module according to claim 5, characterized in that: The buffer fillet is located on a side of the bent portion close to the light bar, and the radius of the buffer fillet is 0.15 mm.

7. The backlight module according to claim 5, characterized in that: The transition between the bottom plate and the bent portion includes a rounded corner, and the rounded corner is located on a side of the bent portion away from the light bar; The radius of the bending fillet is 0.35 mm.

8. The backlight module according to claim 3, characterized in that: The length of the boss portion is greater than 0.75 mm.

9. The backlight module according to claim 1, characterized in that: The light bar comprises a strip-shaped flexible circuit board and a plurality of light sources electrically connected to the strip-shaped flexible circuit board; The light bar is arranged on at least one side of the light guide plate.

10. The backlight module according to claim 1, characterized in that: The light bar includes an insulating film covering the surface of the back plate, a wiring layer formed on the surface of the insulating film, and a light source connected to the wiring layer.

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

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