Backlight source module and liquid crystal display device

Abstract

The utility model discloses a backlight source module. The backlight source module comprises a backlight source; the backlight FPC comprises a backlight connecting part, a first lap joint part and a light sensing part which are connected with one another, the backlight connecting part is electrically connected with the backlight source, a light through hole is formed in the light sensing part, and a light sensing bonding pad surrounding the light through hole is arranged on the back face of the light sensing part; and the photosensitive element is welded on a photosensitive bonding pad on the back surface of the photosensitive part, and a photosensitive surface of the photosensitive element is exposed from the light through hole. The backlight source module can reduce the material cost. The utility model further discloses a liquid crystal display device which comprises the backlight source module.

Description

Technical Field

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

[0002] Existing liquid crystal display devices generally have a photosensitive element next to the display area to sense the ambient light intensity and automatically adjust the backlight brightness of the liquid crystal display device. Currently, the liquid crystal module and the photosensitive element are attached to different areas of the same cover plate during assembly, and then connected to the driver motherboard through their own FPCs for signal transmission, which has a high material cost. Utility Model Content

[0003] In order to solve the above-mentioned deficiencies of the prior art, the utility model provides a backlight module and a liquid crystal display device, which can reduce material costs.

[0004] The technical problem to be solved by the utility model is achieved through the following technical solutions:

[0005] A backlight module, comprising:

[0006] Backlight source;

[0007] A backlight FPC, comprising a backlight connecting portion, a first overlapping portion and a photosensitive portion connected to each other, wherein the backlight connecting portion is electrically connected to the backlight source, the photosensitive portion is provided with a light through hole, and a photosensitive pad surrounding the light through hole is provided on the back of the photosensitive portion;

[0008] The photosensitive element is welded on the photosensitive pad on the back side of the photosensitive part, and its photosensitive surface is exposed from the light-through hole.

[0009] Furthermore, the backlight source includes a frame and a light guide plate and an LED light source arranged in the frame, and the LED light source is located on the light output surface of the light guide plate; the backlight connecting part of the backlight FPC extends into the frame of the backlight source, and the LED light source is mounted on the backlight connecting part of the backlight FPC.

[0010] A liquid crystal display device, comprising:

[0011] LCD screen;

[0012] The backlight module is arranged on the back of the liquid crystal screen;

[0013] A driving mainboard, arranged on the back side of the backlight source;

[0014] The main screen FPC includes a main screen connection part, a second overlap part and a main board connection part which are connected to each other. The main screen connection part is electrically connected to the liquid crystal screen, the second overlap part is electrically connected to the first overlap part of the backlight FPC, and the main board connection part is electrically connected to the driving main board.

[0015] Furthermore, the liquid crystal display device also includes a protective cover, the protective cover includes a visible area and a photosensitive area, the liquid crystal screen is arranged on the visible area on the back of the protective cover, and the photosensitive part of the backlight FPC is arranged on the photosensitive area on the back of the protective cover.

[0016] Furthermore, the photosensitive portion of the backlight FPC is bonded to the photosensitive area on the back side of the protective cover plate by means of annular or frame-shaped double-sided adhesive.

[0017] Furthermore, the double-sided adhesive tape is black double-sided adhesive tape.

[0018] Furthermore, a first moth-eye film covering the light-through hole is provided between the photosensitive portion of the backlight FPC and the double-sided adhesive.

[0019] Furthermore, a second moth-eye film covering the light-through hole is provided between the photosensitive area of ​​the protective cover and the double-sided adhesive.

[0020] Furthermore, a semi-transparent ink is provided on the photosensitive area on the back side of the protective cover.

[0021] Furthermore, black ink is provided on the back side of the protective cover plate, and the black ink avoids the visible area and the photosensitive area.

[0022] The utility model has the following beneficial effects: the backlight source module of the utility model mounts the photosensitive element on the backlight FPC of the backlight source, and opens a light-through hole on the backlight FPC to expose the photosensitive surface of the photosensitive element. During assembly, the photosensitive element and the backlight source are electrically connected to a driving mainboard of a liquid crystal display device through the backlight FPC for signal transmission. The photosensitive element does not need a special FPC to be connected to the driving mainboard, which saves the material cost of one FPC and also reduces the FPC connection process. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a front structural schematic diagram of the backlight module provided by the utility model.

[0024] Figure 2 for Figure 1 The AA cross-sectional structure diagram of the backlight module is shown.

[0025] Figure 3 This is a front structural schematic diagram of a liquid crystal display device provided by the utility model.

[0026] Figure 4 for Figure 3 Schematic diagram of the stacking structure of a liquid crystal display device shown.

[0027] Figure 5 This is a schematic diagram of the stacking structure of the liquid crystal display device provided by the utility model. DETAILED DESCRIPTION

[0028] The present invention is described in detail below in conjunction with the accompanying drawings and embodiments, examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0029] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0030] In addition, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first", "second", and "third" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0031] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix", "set" and the like 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 a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or 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. Embodiment 1

[0032] like Figure 1 and 2 As shown, a backlight module comprises:

[0033] Backlight source 31;

[0034] The backlight FPC 32 includes a backlight connection portion 321, a first overlap portion 322 and a photosensitive portion 323 connected to each other. The backlight connection portion 321 is electrically connected to the backlight source 31. The photosensitive portion 323 is provided with a light through hole 324. A photosensitive pad 325 surrounding the light through hole 324 is provided on the back of the photosensitive portion 323.

[0035] The photosensitive element 33 is welded on the photosensitive pad 325 on the back side of the photosensitive portion 323 , and the photosensitive surface 331 thereof is exposed from the light-through hole 324 .

[0036] The backlight source module of the present invention mounts the photosensitive element 33 on the backlight FPC 32 of the backlight source 31, and opens a light through hole 324 on the backlight FPC 32 to expose the photosensitive surface 331 of the photosensitive element 33. During assembly, the photosensitive element 33 and the backlight source 31 are electrically connected to the driving motherboard of the liquid crystal display device through the backlight FPC 32 for signal transmission. The photosensitive element 33 does not need a special FPC to be connected to the driving motherboard, which saves the material cost of an FPC and also reduces the FPC connection process.

[0037] After the backlight FPC32 is electrically connected to the backlight source 31, it has a relative front and back side when unfolded into a plane. The front side of the backlight FPC32 after unfolding is on the same side as the light emitting side of the backlight source 31, and the back side of the backlight FPC32 after unfolding is opposite to the light emitting side of the backlight source 31.

[0038] The photosensitive element 33 has four pins, namely SDA, IOVDD, SCL and GND. The backlight FPC32 is provided with four pads corresponding to the four pins at the four positions of the light-through hole 324, so that the four pins of the photosensitive element 33 are electrically connected to the I2C routing of the backlight FPC32 through the four pads on the backlight FPC32, and then connected to the first overlapping portion 322 of the backlight FPC32 through the I2C routing.

[0039] The backlight source 31 includes a frame 311 and a light guide plate 312 and an LED light source 313 arranged in the frame 311, and the LED light source 313 is located on the light emitting surface of the light guide plate 312; the backlight connecting part 321 of the backlight FPC32 extends into the frame 311 of the backlight source 31, and the LED light source 313 is mounted on the backlight connecting part 321 of the backlight FPC32.

[0040] The backlight source 31 also includes an optical film assembly 314 including a diffusion film, a lower light enhancement film and an upper light enhancement film arranged on the light emitting surface of the light guide plate 312, and a reflective sheet 315 arranged on the back side of the light guide plate 312 opposite to its light emitting surface. Of course, the internal structure of the backlight source 31 can be varied and is not limited to the description in this embodiment. Embodiment 2

[0041] like Figure 3 and 4 As shown, a liquid crystal display device comprises:

[0042] LCD screen 20;

[0043] The backlight module 30 described in the first embodiment is disposed on the back of the liquid crystal screen 20;

[0044] A driving main board 40 is disposed on the back side of the backlight source 31;

[0045] The main screen FPC50 includes a main screen connecting part 51, a second overlapping part 52 and a main board connecting part 53 which are connected to each other. The main screen connecting part 51 is electrically connected to the liquid crystal screen 20, the second overlapping part 52 is electrically connected to the first overlapping part 322 of the backlight FPC32, and the main board connecting part 53 is electrically connected to the driving main board 40.

[0046] The liquid crystal display device of the present invention can simplify the FPC connection structure of the product and make the internal structure of the product more compact by electrically connecting the backlight FPC 32 connected to the backlight source 31 and carrying the photosensitive element 33 to the main screen FPC 50 of the liquid crystal screen 20, and connecting the liquid crystal screen 20, the backlight source 31 and the photosensitive element 33 to the driving main board 40 through the main screen FPC 50. Embodiment 3

[0047] As an optimization solution of the second embodiment, in this embodiment, if Figure 5 As shown, the liquid crystal display device also includes a protective cover plate 10, which includes a visible area and a photosensitive area. Black ink 11 is provided on the back of the protective cover plate 10, and the black ink 11 avoids the visible area and the photosensitive area; a semi-transparent ink 12 is provided on the photosensitive area on the back of the protective cover plate 10.

[0048] The liquid crystal screen 20 is disposed on a visible area on the back side of the protective cover 10 , and the photosensitive portion 323 of the backlight FPC 32 is disposed on a photosensitive area on the back side of the protective cover 10 .

[0049] Preferably, the semi-transparent ink 12 is gray ink with a transmittance between 40% and 60%, so as to hide the photosensitive area and the photosensitive element 33 to a certain extent, and prevent the photosensitive area and the photosensitive element 33 from destroying the appearance consistency of the protective cover 10.

[0050] In this embodiment, the liquid crystal screen 20 is attached to the visible area on the back side of the protective cover plate 10 by means of OCA glue 60 .

[0051] The OCA adhesive 60, also called OCA optical adhesive (Optically Clear Adhesive), is a special adhesive used for bonding transparent optical elements (such as lenses, etc.), belonging to the category of pressure-sensitive adhesives. Its basic characteristics include colorless transparency, light transmittance of more than 90%, good bonding strength, and can be cured at room temperature or medium temperature with small curing shrinkage. Specifically, OCA optical adhesive is made of optical acrylic adhesive into a substrate-free high-transparency double-sided bonding tape. Its advantages include high clarity, strong light transmittance (full light transmittance>90%), high adhesion, water and high temperature resistance, and UV resistance. In addition, OCA optical adhesive also has a controlled thickness, which can provide uniform spacing, and will not cause yellowing, peeling, and deterioration problems after long-term use.

[0052] The photosensitive portion 323 of the backlight FPC 32 is attached to the photosensitive area on the back side of the protective cover 10 through a ring-shaped or frame-shaped double-sided adhesive 70 .

[0053] Preferably, the double-sided adhesive 70 is a black double-sided adhesive, which, in addition to bonding and fixing the photosensitive portion 323 of the backlight FPC32 and the protective cover 10, is also used for shading to prevent backlight from passing through the gap between the photosensitive portion 323 of the backlight FPC32 and the protective cover 10, thereby improving the sensing accuracy of the photosensitive element 33 to ambient light.

[0054] Since the photosensitive portion 323 of the backlight FPC32 is adhered to the photosensitive area on the back side of the protective cover 10 through the ring-shaped or frame-shaped double-sided adhesive 70, there is an air layer between the photosensitive area and the photosensitive element 33. The refractive index of the air layer is greatly different from that of the protective cover 10, which easily causes large reflected light and affects the sensing accuracy of the photosensitive element 33 to ambient light. Therefore, a first moth-eye film 80 covering the light-through hole 324 is provided between the photosensitive portion 323 of the backlight FPC32 and the double-sided adhesive 70, and a second moth-eye film 90 covering the light-through hole 324 is provided between the photosensitive area of ​​the protective cover 10 and the double-sided adhesive 70.

[0055] The moth-eye film is an optical film with an array of nano-scale protrusions on the surface. It is a bionic product that imitates the fine concave-convex structure in the eyes of moths. When the sub-micrometer structure size on the surface of the material is smaller than the wavelength of visible light, the light wave will not be able to recognize the microstructure, so the refractive index on the surface of the material changes continuously along the depth direction, which can reduce the reflection phenomenon caused by the sharp change of the refractive index. The utility model arranges the first moth-eye film 80 and the second moth-eye film 90 on both sides of the air layer respectively to reduce the reflectivity of the ambient light when passing through the air layer, thereby improving the sensing accuracy of the photosensitive element 33 to the ambient light.

[0056] The first moth-eye film 80 is disposed on the photosensitive portion 323 of the backlight FPC 32 , and can also improve the FPC strength of the photosensitive portion 323 , so as to improve the yield of welding the photosensitive element 33 on the photosensitive portion 323 .

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of the utility model rather than to limit them. Although the embodiments of the utility model are described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the embodiments of the utility model can still be modified or replaced by equivalents, and these modifications or equivalent replacements cannot cause the modified technical solutions to deviate from the scope of the technical solutions of the embodiments of the utility model.

Claims

1. A backlight module, characterized in that: include: Backlight source; A backlight FPC, comprising a backlight connecting portion, a first overlapping portion and a photosensitive portion connected to each other, wherein the backlight connecting portion is electrically connected to the backlight source, the photosensitive portion is provided with a light through hole, and a photosensitive pad surrounding the light through hole is provided on the back of the photosensitive portion; The photosensitive element is welded on the photosensitive pad on the back side of the photosensitive part, and its photosensitive surface is exposed from the light-through hole.

2. The backlight module according to claim 1, characterized in that: The backlight source includes a frame and a light guide plate and an LED light source arranged in the frame, and the LED light source is located on the light emitting surface of the light guide plate; the backlight connecting part of the backlight FPC extends into the frame of the backlight source, and the LED light source is mounted on the backlight connecting part of the backlight FPC.

3. A liquid crystal display device, characterized in that: include: LCD screen; The backlight module of claim 1 is arranged on the back side of the liquid crystal screen; A driving mainboard, arranged on the back side of the backlight source; The main screen FPC includes a main screen connection part, a second overlap part and a main board connection part which are connected to each other. The main screen connection part is electrically connected to the liquid crystal screen, the second overlap part is electrically connected to the first overlap part of the backlight FPC, and the main board connection part is electrically connected to the driving main board.

4. The liquid crystal display device according to claim 3, characterized in that: The liquid crystal display device also includes a protective cover plate, which includes a visible area and a photosensitive area. The liquid crystal screen is arranged on the visible area on the back of the protective cover plate, and the photosensitive part of the backlight FPC is arranged on the photosensitive area on the back of the protective cover plate.

5. The liquid crystal display device according to claim 4, characterized in that: The photosensitive portion of the backlight FPC is bonded to the photosensitive area on the back of the protective cover plate by means of annular or frame-shaped double-sided adhesive.

6. The liquid crystal display device according to claim 5, characterized in that: The double-sided adhesive is black.

7. The liquid crystal display device according to claim 5, characterized in that: A first moth-eye film covering the light-through hole is provided between the photosensitive portion of the backlight FPC and the double-sided adhesive.

8. The liquid crystal display device according to claim 5 or 7, characterized in that: A second moth-eye film covering the light-through hole is arranged between the photosensitive area of ​​the protective cover and the double-sided adhesive.

9. The liquid crystal display device according to claim 4, characterized in that: Semi-transparent ink is provided on the photosensitive area on the back of the protective cover plate.

10. The liquid crystal display device according to claim 4, characterized in that: Black ink is provided on the back side of the protective cover plate, and the black ink avoids the visible area and the photosensitive area.

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