Backlight module

Abstract

The utility model discloses a backlight module which comprises a die casting, a middle iron frame, a light bar and an optical assembly, the middle iron frame covers the die casting so that a containing cavity can be formed between the middle iron frame and the die casting, the optical assembly is laid in the containing cavity, and the light bar is fixed to the inner side wall of the die casting; a light shielding layer is arranged between the optical assembly and the middle iron frame, covers the circumferential edge of the upper surface of the optical assembly and is located below the middle iron frame. According to the backlight module, the light shielding layer covers the peripheral edge of the upper surface of the optical assembly to shield light on the edge of the upper surface of the optical assembly, so that the edge of the optical assembly is prevented from shining under the condition of a narrow frame, and the light emitting effect and the light emitting uniformity of the backlight module are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of liquid crystal display, in particular to a backlight module. Background Art

[0002] The backlight module of a vehicle-mounted liquid crystal display device includes a die-casting part, a middle iron frame, a light bar and an optical component. The middle iron frame and the die-casting part are assembled in an inverted manner to form a receiving cavity, and both the light bar and the optical component are installed in the receiving cavity.

[0003] In order to obtain a larger visible area, the display device pursues a narrow bezel design. However, the narrow bezel cannot effectively cover the edge of the optical component. Therefore, when the display device is in use, the edge of the optical component emits light, which affects the light output effect of the backlight module. Summary of the Utility Model

[0004] In order to overcome at least one defect of the above-mentioned prior art, the utility model provides a backlight module, which solves the problem of edge light emission in the case of a narrow bezel by covering the edge of the optical component with a light-shielding layer, thereby improving the light output effect of the backlight module.

[0005] The technical solution adopted by the utility model to solve its problems is as follows:

[0006] A backlight module, comprising: a die-casting part, a middle iron frame, a light bar and an optical component. The middle iron frame covers the die-casting part to form a receiving cavity therebetween. The optical component is laid in the receiving cavity, and the light bar is fixed on the inner side wall of the die-casting part;

[0007] A light-shielding layer is provided between the optical component and the middle iron frame. The light-shielding layer covers the circumferential edge of the upper surface of the optical component and is located below the middle iron frame.

[0008] Further, the light-shielding layer is a black single-sided adhesive or a gray single-sided adhesive. The lower surface of the light-shielding layer is adhesively fixed to the circumferential edge of the upper surface of the optical component, and the upper surface of the light-shielding layer abuts against the lower surface of the middle iron frame.

[0009] Further, the optical component includes a reflection film, a light guide plate and an optical film disposed in sequence from bottom to top. The lower surface of the light-shielding layer is adhesively fixed to the circumferential edge of the upper surface of the optical film.

[0010] Further, the optical film includes a diffusion film, a lower brightness enhancement film, an upper brightness enhancement film and a brightness enhancement film disposed in sequence from bottom to top. The lower surface of the light-shielding layer is adhesively fixed to the circumferential edge of the upper surface of the brightness enhancement film.

[0011] Further, the reflection film, the light guide plate, the diffusion film, the lower brightness enhancement film, the upper brightness enhancement film and the brightness enhancement film are adhesively fixed to each other in sequence by double-sided adhesive, and both the reflection film and the light bar are adhesively fixed to the die-casting part by double-sided adhesive.

[0012] Further, positioning posts are convexly provided on the circumferential edge of the light guide plate, and the optical film is provided with mating lugs corresponding to the positioning posts. The lugs are sleeved on the positioning posts so that the optical film covers the light guide plate.

[0013] Further, there is a gap between the corners of the light guide plate and the inner side wall of the die-cast part, and a buffer pad is press-fitted in the gap.

[0014] Further, the die-cast part includes a first inner side wall and a second inner side wall arranged adjacent to each other, and the lamp strip is fixed on the first inner side wall;

[0015] The reflective film includes a bottom film and a side film. The bottom film is laid in the accommodating cavity and is located below the light guide plate, and the side film is fixed on the second inner side wall and is located at the side part of the light guide plate.

[0016] Further, the die-cast part includes a bottom plate and side plates. The side plates are arranged on the circumference of the bottom plate, and the bottom plate and the side plates are of an integral structure. The optical component is laid on the bottom plate, the lamp strip is fixed on the inner wall of the side plate, and the middle iron frame is covered on the side plate through a snap structure so that the middle iron frame is detachably connected to the die-cast part.

[0017] Further, the periphery of the backlight module is coated with an edge-sealing glue. The edge-sealing glue is coated on the outer side walls of the die-cast part and the middle iron frame and is bent towards the bottom of the die-cast part.

[0018] The beneficial effects of the backlight module provided by the present utility model are as follows:

[0019] By covering the circumferential edge of the upper surface of the optical component with a light-shielding layer to block the bright light at the edge of the upper surface of the optical component, the brightening of the edge of the optical component is avoided in the case of a narrow frame, thereby improving the light-emitting effect and light-emitting uniformity of the backlight module. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is an exploded view of the backlight module of the present utility model;

[0021] Figure 2 is an assembly drawing of the light guide plate and the optical film of the present utility model;

[0022] Figure 3 is an assembly drawing of the die-cast part and the middle iron frame of the present utility model;

[0023] Figure 4 is an exploded view of the die-cast part and the middle iron frame of the present utility model.

[0024] Among them, the meanings of the reference numerals are as follows:

[0025] 1. Die-cast part; 11. Bottom plate; 12. Side plate; 121. Card slot; 122. Inner groove; 123. Protrusion; 2. Middle iron frame; 21. Flange; 22. Locking block; 23. Locking projection; 24. Lobe; 241. Through slot; 3. Light bar; 4. Optical component; 41. Reflective film; 411. Bottom film; 412. Side film; 42. Light guide plate; 421. Positioning post; 43. Optical film; 431. Diffusion film; 432. Lower brightness enhancement film; 433. Upper brightness enhancement film; 434. Brightness enhancement film; 435. Locking ear; 5. Light-shielding layer; 6. Buffer pad; 7. Edge-sealing glue. Detailed implementation

[0026] For better understanding and implementation, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0027] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0029] Refer to Figure 1 , the present invention discloses a backlight module, including: a die-cast part 1, a middle iron frame 2, a light bar 3 and an optical component 4. The middle iron frame 2 covers the die-cast part 1 to form a receiving cavity therebetween. The optical component 4 is laid in the receiving cavity, and the light bar 3 is fixed on the inner side wall of the die-cast part 1. A light-shielding layer 5 is provided between the optical component 4 and the middle iron frame 2. The light-shielding layer 5 covers the circumferential edge of the upper surface of the optical component 4, and the light-shielding layer 5 is located below the middle iron frame 2.

[0030] Thus, the present invention covers the circumferential edge of the upper surface of the optical component 4 with the light-shielding layer 5 to block the bright light at the edge of the upper surface of the optical component 4, thereby avoiding the edge of the optical component 4 from emitting light in the case of a narrow frame, and improving the light output effect and light output uniformity of the backlight module.

[0031] Among them, the light-shielding layer 5 is a black single-sided adhesive or a gray single-sided adhesive. The lower surface of the light-shielding layer 5 is adhesively fixed to the circumferential edge of the upper surface of the optical component 4, and the upper surface of the light-shielding layer 5 abuts against the lower surface of the middle iron frame 2. The light-shielding layer 5 has a good light-shielding effect, and the adhesive layer structure can ensure that the light-shielding layer 5 firmly covers the circumferential edge of the upper surface of the optical component 4, so as to achieve the purpose of long-term light-shielding to avoid edge brightening. Of course, the light-shielding layer 5 can also be a gray single-sided adhesive, which also has a good light-shielding effect.

[0032] On the basis of the above structure, the structure of the optical component 4 is that the optical component 4 includes a reflective film 41, a light guide plate 42, and an optical film 43 arranged in sequence from bottom to top. The lower surface of the light-shielding layer 5 is adhesively fixed to the circumferential edge of the upper surface of the optical film 43. Thus, by adhesively covering the light-shielding layer 5 on the circumferential edge of the upper surface of the optical film 43, the effect of avoiding the edge of the optical film 43 from brightening in the case of a narrow border is achieved.

[0033] Specifically, the optical film 43 includes a diffusion film 431, a lower brightness enhancement film 432, an upper brightness enhancement film 433, and a brightness enhancement film 434 arranged in sequence from bottom to top. The lower surface of the light-shielding layer 5 is adhesively fixed to the circumferential edge of the upper surface of the brightness enhancement film 434. Moreover, the reflective film 41, the light guide plate 42, the diffusion film 431, the lower brightness enhancement film 432, the upper brightness enhancement film 433, and the brightness enhancement film 434 are adhesively fixed to each other in sequence by double-sided adhesives, and both the reflective film 41 and the lamp strip 3 are adhesively fixed to the die-casting 1 by double-sided adhesives, so as to stably install the lamp strip 3 and the optical component 4 in the accommodation cavity formed by the cover of the die-casting 1 and the middle iron frame 2.

[0034] At the same time, referring to Figure 2 , on the circumferential edge of the light guide plate 42, positioning posts 421 protrude upward. The optical film 43 is provided with mating lugs 435 corresponding to the positioning posts 421, and the lugs 435 are sleeved on the positioning posts 421 so that the optical film 43 covers the light guide plate 42. The diffusion film 431, the lower brightness enhancement film 432, the upper brightness enhancement film 433, and the brightness enhancement film 434 are all provided with mating lugs 435 corresponding to the positioning posts 421, and multiple positioning posts 421 can be arranged at intervals, thereby improving the installation stability of the diffusion film 431, the lower brightness enhancement film 432, the upper brightness enhancement film 433, and the brightness enhancement film 434.

[0035] In order to ensure that the diffusion film 431, the lower brightness enhancement film 432, the upper brightness enhancement film 433, and the brightness enhancement film 434 can all be stably installed, the height of the positioning posts 421 should not be less than the total thickness of the diffusion film 431, the lower brightness enhancement film 432, the upper brightness enhancement film 433, and the brightness enhancement film 434.

[0036] In addition, after the light guide plate 42 is installed, its stability must be ensured, and damage or abnormal noise at the corners must be avoided. For this purpose, there is a gap between the corners of the light guide plate 42 and the inner side wall of the die-casting 1, and a buffer pad 6 is press-fitted in the gap. The setting of the buffer pad 6 has a certain buffering effect to prevent the corners of the light guide plate 42 from colliding with the inner side wall of the die-casting 1 and being damaged.

[0037] For the reflective film 41, it is used to reflect the light emitted by the lamp strip 3 to the light guide plate 42. Since the lamp strip 3 is adhered to the inner side wall of the die-casting 1, the light emitted by it is concentrated towards the side. For this purpose, the die-casting 1 includes a first inner side wall and a second inner side wall arranged adjacent to each other, and the lamp strip 3 is fixed to the first inner side wall. The reflective film 41 includes a bottom film 411 and a side film 412. The bottom film 411 is laid in the accommodating cavity and is located below the light guide plate 42, and the side film 412 is fixed to the second inner side wall and is located on the side of the light guide plate 42. The light emitted by the lamp strip 3 is jointly reflected by the side film 412 and the bottom film 411 to be transmitted to the light guide plate 42, improving the light output intensity of the backlight module.

[0038] Regarding the covering structure of the die-casting 1 and the iron middle frame, refer to Figure 3 and Figure 4 , the die-casting 1 includes a bottom plate 11 and side plates 12. The side plates 12 are arranged circumferentially on the bottom plate 11, and the bottom plate 11 and the side plates 12 are of an integral structure. The optical component 4 is laid on the bottom plate 11, and the lamp strip 3 is fixed to the inner wall of the side plates 12. The iron middle frame 2 is covered on the side plates 12 through a snap structure so that the iron middle frame 2 and the die-casting 1 are detachably connected. The iron middle frame 2 and the die-casting 1 are connected through the snap structure, which can not only ensure stable assembly but also facilitate disassembly and replacement of the internal lamp strip 3 and optical component.

[0039] Specifically, the side plate 12 includes an outer plate and an inner plate. The outer plate covers the outer wall of the inner plate. The middle iron frame 2 covers the inner plate. The outer plate is arranged outside the middle iron frame 2 and extends upward beyond the middle iron frame 2 to form an overhanging part. The edge of the middle iron frame 2 extends upward to form a folded edge 21, and the folded edge 21 fits against the inner wall of the overhanging part. The folded edge 21 extends toward the overhanging part to form a clamping block 22. A mating clamping groove 121 is provided at the top of the overhanging part corresponding to the clamping block 22, and the clamping block 22 is placed on the clamping groove 121. The middle iron frame 2 extends toward the side plate 12 and then bends upward to form a clamping projection 23. The position of the clamping projection 23 corresponds to the overhanging part. A mating inner groove 122 is provided at the overhanging part corresponding to the clamping projection 23, and the clamping projection 23 is embedded in the inner groove 122. For the part of the side plate 12 where the outer plate is not provided, the edge of the middle iron frame 12 bends downward to form a lug 24. The lug 24 fits against the outer wall of the inner plate. A convex block 123 protrudes from the outer wall of the inner plate. A mating through groove 241 is provided at the lug 24 corresponding to the convex block 123, and the convex block 24 is clamped in the through groove 241. Thus, through the cooperation of the three snap structures of the clamping block 22 and the clamping groove 121, the clamping projection 23 and the inner groove 122, and the convex block 123 and the through groove 241, combined with the tight fit of the folded edge 21 and the inner wall of the outer plate, the middle iron frame 2 is tightly connected to the die-casting part 1. The quantity and position of the composite snap structure are set according to needs.

[0040] On this basis, a side glue 7 is coated on the periphery of the backlight module. The side glue 7 covers the outer side walls of the die-casting part 1 and the middle iron frame 2 and bends toward the bottom of the die-casting part 1. The setting of the side glue 7 can prevent light leakage from the side of the backlight module and prevent impurities from entering the inside of the backlight module. The side glue 7 can completely cover the periphery of the backlight module or can be arranged at intervals at positions where light leakage and / or entry of impurities are likely to occur.

[0041] The technical means disclosed in the solution of the present utility model are not limited to the technical means disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present utility model, several improvements and retouches can be made, and these improvements and retouches are also regarded as the protection scope of the present utility model.

Claims

1. A backlight module, characterized in that: include: A die casting (1), a middle iron frame (2), a light bar (3) and an optical component (4), wherein the middle iron frame (2) covers the die casting (1) to form a receiving cavity between the two, the optical component (4) is laid in the receiving cavity, and the light bar (3) is fixed to the inner side wall of the die casting (1); A light shielding layer (5) is provided between the optical component (4) and the middle iron frame (2), the light shielding layer (5) covers the circumferential edge of the upper surface of the optical component (4), and the light shielding layer (5) is located below the middle iron frame (2).

2. The backlight module according to claim 1, characterized in that: The shading layer (5) is a black single-sided adhesive or a grey single-sided adhesive. The lower surface of the shading layer (5) is bonded and fixed to the circumferential edge of the upper surface of the optical component (4). The upper surface of the shading layer (5) abuts against the lower surface of the middle iron frame (2).

3. The backlight module according to claim 2, characterized in that: The optical component (4) comprises a reflective film (41), a light guide plate (42) and an optical film (43) which are arranged in sequence from bottom to top, and the lower surface of the light shielding layer (5) is bonded and fixed to the circumferential edge of the upper surface of the optical film (43).

4. The backlight module according to claim 3, characterized in that: The optical film (43) comprises a diffusion film (431), a lower brightness enhancement film (432), an upper brightness enhancement film (433) and a brightness enhancement film (434) which are arranged in sequence from bottom to top, and the lower surface of the light shielding layer (5) is bonded and fixed to the circumferential edge of the upper surface of the brightness enhancement film (434).

5. The backlight module according to claim 4, characterized in that: The reflective film (41), the light guide plate (42), the diffusion film (431), the lower light-enhancing film (432), the upper light-enhancing film (433) and the brightness-enhancing film (434) are bonded and fixed in sequence by double-sided adhesive tape, and the reflective film (41) and the light bar (3) are bonded and fixed to the die-casting (1) by double-sided adhesive tape.

6. The backlight module according to claim 3, characterized in that: A positioning column (421) is protrudingly provided on the circumferential edge of the light guide plate (42); the optical film (43) is provided with a matching ear (435) corresponding to the positioning column (421); the ear (435) is sleeved on the positioning column (421) so that the optical film (43) covers the light guide plate (42).

7. The backlight module according to claim 3, characterized in that: There is a gap between the corner of the light guide plate (42) and the inner side wall of the die casting (1), and a buffer pad (6) is provided in the gap for interference fit.

8. The backlight module according to claim 3, characterized in that: The die casting (1) comprises a first inner side wall and a second inner side wall which are arranged adjacent to each other, and the light bar (3) is fixed to the first inner side wall; The reflective film (41) comprises a bottom film (411) and a side film (412); the bottom film (411) is laid in the accommodating cavity and is located below the light guide plate (42); and the side film (412) is fixed to the second inner side wall and is located on the side of the light guide plate (42).

9. The backlight module according to claim 1, characterized in that: The die-casting (1) comprises a bottom plate (11) and a side plate (12), wherein the side plate (12) is arranged in the circumference of the bottom plate (11), and the bottom plate (11) and the side plate (12) are an integral structure, the optical component (4) is laid on the bottom plate (11), the light bar (3) is fixed to the inner wall of the side plate (12), and the middle iron frame (2) is covered on the side plate (12) by a snap-fit ​​structure so that the middle iron frame (2) and the die-casting (1) are detachably connected.

10. The backlight module according to claim 9, characterized in that: The circumference of the backlight module is coated with an edge glue (7), and the edge glue (7) is coated on the outer side walls of the die casting (1) and the middle iron frame (2) and is bent toward the bottom of the die casting (1).

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