CN111239885A

CN111239885A - Backlight module and display device

Info

Publication number: CN111239885A
Application number: CN202010143983.XA
Authority: CN
Inventors: 郑慧君; 郭运涛; 林士斌
Original assignee: AU Optronics Suzhou Corp Ltd; AU Optronics Corp
Current assignee: AU Optronics Suzhou Corp Ltd; AU Optronics Corp
Priority date: 2020-03-04
Filing date: 2020-03-04
Publication date: 2020-06-05
Also published as: TWI728821B; TW202134758A

Abstract

The invention discloses a backlight module, which comprises a light guide plate, a light source, a pasting structure and a frame. The light guide plate comprises a light incident side and a bottom surface. The light source is arranged on the light incident side. The pasting structure is arranged in a first area of the bottom surface far away from the light incident side and is formed by stacking a first material layer and a second material layer. The frame comprises a bearing surface. The light guide plate is positioned on the bearing surface. The adhesive structure connects the light guide plate to the frame. The elasticity of the second material layer is greater than the elasticity of the first material layer. A display device is also provided.

Description

Backlight module and display device

Technical Field

The present invention relates to an optical device and an electronic apparatus, and more particularly, to a backlight module and a display device.

Background

Among conventional flat display devices, liquid crystal display devices are still widely used in life and work of people. The lcd panel of the lcd device needs additional backlight to form an image, so the uniformity, lifetime and brightness of the backlight directly affect the image quality provided by the lcd device.

An existing backlight module may include a light guide plate, a light source, and a frame, and a connection between the light guide plate and the frame may be connected through a connection layer having a double-sided tape on both sides. Existing tie layers include those formed of polyethylene terephthalate (PET). However, after a long time of use, the connecting layer formed by PET is aged and deformed, resulting in displacement of the light guide plate connected thereto, thereby changing the distance between the light source and the light guide plate and affecting the brightness and uniformity of the backlight. Therefore, how to provide a backlight module with high stability without affecting the assembly difficulty is still one of the main problems to be solved by those skilled in the art.

Disclosure of Invention

The invention provides a backlight module and a display device, which have higher stability and longer service life.

An embodiment of the invention provides a backlight module, which includes a light guide plate, a light source, a bonding structure and a frame. The light guide plate comprises a light incident side and a bottom surface. The light source is arranged on the light incident side. The pasting structure is arranged in a first area of the bottom surface far away from the light incident side. The pasting structure is formed by stacking a first material layer and a second material layer. The elasticity of the second material layer is greater than the elasticity of the first material layer. The frame comprises a bearing surface. The light guide plate is positioned on the bearing surface. The adhesive structure connects the light guide plate to the frame.

An embodiment of the invention provides a display device, which includes a display panel and the backlight module, wherein the display panel is disposed on the backlight module. The light guide plate comprises a light emergent surface facing the display panel. The bottom surface is opposite to the light-emitting surface, and the light-in side is connected with the light-emitting surface and the bottom surface.

As can be seen from the above, in the backlight module of the embodiment of the invention, the light guide plate is connected to the frame by the adhesion structure, and the adhesion structure is formed by stacking the first material layer and the second material layer, so that the light guide plate can be maintained at a proper position on the frame for a long time. The display device provided by the embodiment of the invention can provide good pictures for a long time, and the picture of the display device is prevented from being influenced by the aging of the light guide plate.

Drawings

FIG. 1 is a schematic perspective exploded view of a display device according to an embodiment of the present invention;

FIG. 2 is a schematic plan view of a backlight module according to an embodiment of the invention;

FIG. 3 is a schematic cross-sectional view taken along section line 3-3 of FIG. 2;

FIG. 4 is another cross-sectional view of a backlight module according to an embodiment of the present invention;

FIG. 5 is a partial enlarged view of the region C according to FIG. 3;

FIG. 6 is a schematic cross-sectional view of a backlight module according to another embodiment of the present invention;

FIG. 7 is a schematic cross-sectional view of a backlight module according to still another embodiment of the present invention;

fig. 8 is a schematic cross-sectional view of a backlight module according to still another embodiment of the invention.

Wherein, the reference numbers:

a is the first region

B the second region

C region

d1 first direction

d2 second direction

g1 distance

g2 distance

g3 distance

g4 distance

h1 first thickness

h2 second thickness

h3 third thickness

h4 fourth thickness

3-3 cut surface line

10 display device

100 backlight module

100A backlight module

100B backlight module

100C backlight module

110 light guide plate

111 incident light side

112 light-emitting surface

113 bottom surface

120 light source

121 flexible circuit board

122 switching circuit board

123 control circuit board

130: frame

131 bearing surface

132 reflective film

140 sticking structure

141 first material layer

142 second material layer

143 first adhesive layer

144 second adhesive layer

150 reflective element

160 rubber frame

200 display panel

201 display surface

Detailed Description

Embodiments of the invention provide a backlight module, which can be applied to a display device. Embodiments of the present invention provide a display device, which can be applied to a computer screen, a smart phone, a tablet computer, or a television screen, but the present invention is not limited thereto.

In the drawings, the thickness of layers, films, panels, regions, etc. have been exaggerated for clarity. Like reference numerals refer to like elements throughout the specification. It will be understood that when an element such as a layer, film, panel or region is referred to as being "on" or "connected to" another element, it can be directly on or connected to the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" or "directly connected to" another element, there are no intervening elements present. As used herein, "connected" may refer to physical or electrical connections. Further, "electrically connected" or "coupled" may mean that there are additional elements between the elements.

It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. Thus, a "first element" discussed below could also be termed a "second element" without departing from the teachings herein.

Fig. 1 is a perspective exploded view of a display device according to an embodiment of the present invention. Referring to fig. 1, in the present embodiment, a display device 10 includes a backlight module 100 and a display panel 200, and the display panel 200 is disposed on the backlight module 100.

The backlight module 100 includes a light guide plate 110, a plurality of light sources 120, and a frame 130. The light guide plate 110 includes a light incident side 111 and a light exiting side 112 connected to the light incident side 111, and the light exiting side 112 faces the display panel 120.

The light sources 120 are disposed on the light incident side 111, and light provided by the light sources 120 can be transmitted as illumination light L1 through the light guide plate 110. The illumination light L1 can be emitted from the light emitting surface 112 and transmitted to the display panel 200, so as to form an image on the display surface 201 of the display panel 200.

Fig. 2 is a schematic plan view of a backlight module according to an embodiment of the invention. Referring to fig. 2, the backlight module 100 further includes a bonding structure 140.

The frame 130 includes a supporting surface 131. The light guide plate 110 is disposed on the supporting surface 131 of the frame 130. The adhesive structure 140 connects the light guide plate 110 to the frame 130.

In detail, the backlight module 100 may further include a flexible circuit board 121 electrically connected to the light sources 120. The flexible circuit board 121 is used to transmit driving signals to the light sources 120, but the invention is not limited thereto. In some embodiments, the light sources 120 may be connected to a conductive wire or a circuit board, respectively, so as to transmit driving signals to illuminate the light sources 120. In other embodiments, the light sources 120 may be provided by a light bar, but the invention is not limited thereto.

FIG. 3 is a cross-sectional view of the section line 3-3 of FIG. 2. Referring to fig. 3, the light guide plate 110 further includes a bottom surface 113, and the bottom surface 113 is opposite to the light exit surface 112, and the light incident side 111 is connected to the light exit surface 112 and the bottom surface 113.

The pasting structure 140 is disposed in the first area a of the bottom surface 113 away from the light incident side 111, and the pasting structure 140 is formed by stacking a first material layer 141 and a second material layer 142, and the elasticity of the second material layer 142 is greater than that of the first material layer 141.

Fig. 4 is another cross-sectional view of the backlight module in an embodiment of the invention. Since the light guide plate 110 of the present embodiment is adhered to the supporting surface 131 of the frame 130 by the adhering structure 140, and the adhering structure 140 includes the first material layer 141 and the second material layer 142. Therefore, for example, referring to fig. 4, when the light guide plate 110 is bent toward the first direction d1 after being used for a long time, the second material layer 142 with a larger elasticity can bear the bending of the light guide plate 110 caused by the deformation, and the first material layer 141 can be prevented from being affected by the bent light guide plate 110, so that the adhesive structure 140 can be maintained at the same position on the carrying surface 131.

Further, the toughness of the first material layer 141 is higher than that of the second material layer 142, and when the backlight module 100 needs to be reworked, the adhesive structure 140 having the first material layer 141 can be easily removed from the supporting surface 131.

For example, referring to fig. 3 and fig. 4, the adhesive structure 140 of the present embodiment further includes a first adhesive layer 143 adhered on the first material layer 141 and a second adhesive layer 144 adhered on the second material layer 142, and the first adhesive layer 143, the first material layer 141, the second material layer 142 and the second adhesive layer 144 are sequentially stacked along a direction.

For example, the second material layer 142 may include silicon rubber. The second material layer 142 may be coated with a silicone treatment before the second material layer 142 and the second adhesive layer 144 are bonded, whereby the pretreatment step allows the second adhesive layer 144 to be properly formed on the surface of the second material layer 142.

When the light guide plate 110 is deformed due to long-term use or high temperature environment, the second material layer 142 may also change its shape such that the second adhesive layer 144 is not peeled off from the bottom surface 113 of the light guide plate 110 or the second material layer 142. When the backlight module 100 is reworked, the first material layer 141 with higher toughness is adhered to the first adhesive layer 143 by a surface with higher hardness, so that the adhesive structure 140 can be easily removed from the supporting surface 131 without adhesive residue. In other words, the pasting structure 140 of the present embodiment enables the backlight module 100 to maintain proper brightness after long-term use, and also enables the backlight module 100 to be easily reworked.

Further, referring to fig. 3, in the present embodiment, a distance g1 between the first material layer 141 and the carrying surface 131 is smaller than a distance g2 between the second material layer 142 and the carrying surface 131. In other words, in the paste structure 140, the first material layer 141 and the second material layer 142 are stacked along the first direction d1, the first material layer 141 is located between the second material layer 142 and the carrying surface 131, the second material layer 142 is located between the light guide plate 110 and the first material layer 141, and the first direction d1 is parallel to the normal direction of the carrying surface 131.

The first material layer 141 is adjacent to the supporting surface 131 of the frame 130, and the first material layer 141 can maintain the first adhesive layer 143 in a proper position on the supporting surface 131.

The second material layer 142 is adjacent to the light guide plate 110, so the second material layer 142 can change shape in cooperation with the light guide plate 110 and the second adhesive layer 144 is not peeled off.

For example, the material of the first material layer 141 may include PET, and the material of the second material layer 142 may include silicon rubber. Before the second material layer 142 and the first material layer 141 are stacked on each other, the surface of the first material layer 141 may be coated with a treating agent, thereby bonding the first material layer 141 and the second material layer 142 by calendering. In other embodiments of the present invention, the material of the first material layer 141 may further include Polycarbonate (PC), and the material of the second material layer 142 may include rubber or other elastic plastics.

Therefore, the pasting structure 140 of the present embodiment can be formed by stacking the first material layer 141 and the second material layer 142 in a flush manner, so that the second material layer 142 can provide a sufficient buffering effect in the pasting structure 140. For example, the thickness of the first material layer 141 and the second material layer 142 may fall within a range of 0.1 mm to 0.15 mm.

Further, the thickness of the second material layer 142 is greater than that of the first material layer 141. Fig. 5 is a partial enlarged view of the region C in fig. 3. Referring to fig. 5, the first material layer 141 has a third thickness h3, the second material layer 142 has a fourth thickness h4, and the fourth thickness h4 is greater than the third thickness h 3. Therefore, the second material layer 142 with higher elasticity can provide sufficient buffering effect, and can change the shape in cooperation with the light guide plate 110.

For example, in the present embodiment, the ratio of the third thickness h3 to the fourth thickness h4 is not more than one third, which can have better optical effect.

Referring to fig. 3, in the present embodiment, the backlight module 100 further includes a reflective element 150. The reflective element 150 is disposed on the supporting surface 131, and the reflective element 150 corresponds to a second area B of the bottom surface 113 of the light guide plate 110 adjacent to the light incident side 111, and the second area B is located between the light incident side 111 and the first area a. In detail, the light incident side 111, the second area B and the first area a of the present embodiment are sequentially arranged along the second direction d2, and the first direction d1 is perpendicular to the second direction.

On the other hand, the pasting structure 140 of the embodiment has a first thickness h1, the reflective element 150 has a second thickness h2, and the first thickness h1 is greater than the second thickness h 2. Specifically, the light source 120 is electrically connected to the flexible circuit board 121, and the flexible circuit board 121 can be further electrically connected to the adaptor circuit board 122 to be electrically connected to the control circuit board 123. The adhesive structure 140 of the present embodiment connects the first region a of the bottom surface 113 to the carrying surface 131, so that the light guide plate 110 can be fixed in the frame 130.

Further, on the supporting surface 131 of the frame 130 of the embodiment, the distribution area of the light sources 120 and the distribution area of the pasting structure 140 are located at two sides of the distribution area of the light guide plate 110, and the distribution area of the pasting structure 140 on the supporting surface 131 exceeds the distribution area of the light guide plate 110 on the supporting surface 131. Therefore, the adhesive structure 140 can further connect other elements in the backlight module 100 to the supporting surface 131.

Fig. 6 is a schematic cross-sectional view of a backlight module according to another embodiment of the invention. The backlight module 100A of the present embodiment is similar to the backlight module 100 of the previous embodiment, and similar elements are not described herein again. The backlight module 100A includes a light guide plate 110, a light source 120, a frame 130, an adhesive structure 140, and a reflective element 150, wherein the adhesive structure 140 includes a first material layer 141, a second material layer 142, a first adhesive layer 143, and a second adhesive layer 144.

In the present embodiment, the distribution area of the bonding structure 140 on the supporting surface 131 exceeds the distribution area of the light guide plate 110 on the supporting surface 131. The backlight module 100A further includes a rubber frame 160, and the rubber frame 160 surrounds the light guide plate 110, so the adhesive structure 140 can also connect the rubber frame 160 to the frame 130.

The backlight module according to the embodiment of the invention is not limited to the stacking manner of the first material layer 141 and the second material layer 142 in the above embodiments. Fig. 7 is a schematic cross-sectional view of a backlight module according to still another embodiment of the invention. Referring to fig. 7, the backlight module 100B of the present embodiment is similar to the backlight module 100 of the previous embodiment, and similar elements are not repeated herein. The backlight module 100B includes a light guide plate 110, a light source 120, a frame 130, an adhesive structure 140, and a reflective element 150, wherein the adhesive structure 140 includes a first material layer 141, a second material layer 142, a first adhesive layer 143, and a second adhesive layer 144.

In the present embodiment, the distance g3 between the first material layer 141 and the carrying surface 131 is greater than the distance g4 between the second material layer 142 and the carrying surface 131. In other words, the first material layer 141 is adjacent to the light guide plate 110, so the first material layer 141 can maintain the first adhesive layer 143 in a proper position on the light guide plate 110.

The second material layer 142 is adjacent to the supporting surface 131 of the frame 130, so that the second material layer 142 can change shape in cooperation with the light guide plate 110 and the second adhesive layer 144 cannot be peeled off from the supporting surface 131.

Fig. 8 is a schematic cross-sectional view of a backlight module according to still another embodiment of the invention. Referring to fig. 8, the backlight module 100C of the present embodiment is similar to the backlight module 100 of the previous embodiment, and similar elements are not described again. The backlight module 100C includes a light guide plate 110, a light source 120, a frame 130 and an adhesive structure 140, wherein the adhesive structure 140 includes a first material layer 141, a second material layer 142, a first adhesive layer 143 and a second adhesive layer 144.

In the present embodiment, the supporting surface 131 of the frame 130 of the backlight module 100C is a reflective surface.

In detail, the frame 130 may include a reflective film 132, and the supporting surface 131 is formed on the reflective film 132. The adhesive structure 140 connects the first region a of the bottom surface 113 to the carrying surface 131 provided by the reflective film 132. Therefore, the light guide plate 110 can be fixed on the frame 130 by the adhesive structure 140, and the light guide plate 110 is maintained at a proper position.

On the other hand, an edge of the pasting structure 140 of the backlight module 100C and an edge of the light guide plate 110 away from the light incident side 111 are flush. Therefore, the adhesive structure 140 can fix the light guide plate 110 on the frame 130, and also can reduce the frame area of the backlight module 100C, thereby providing a proper backlight for the narrow-frame display device.

In summary, the backlight module of the embodiment of the invention includes the adhesive structure, the light guide plate can be connected to the frame, the adhesive structure can be prevented from being peeled off due to the deformation of the light guide plate by the second material layer, the adhesive structure can be fixed on the frame by the first material layer, and the adhesive residue can be avoided during heavy industry. The display device provided by the embodiment of the invention can provide good pictures for a long time and can also avoid the influence of the aging of the light guide plate on the pictures of the display device.

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it should be understood that various changes and modifications can be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A backlight module, comprising:

a light guide plate, including a light incident side and a bottom surface:

a light source configured on the light incident side;

the sticking structure is arranged in a first area of the bottom surface, which is far away from the light incidence side, and the sticking structure is formed by stacking a first material layer and a second material layer, wherein the elasticity of the second material layer is greater than that of the first material layer; and

and the frame comprises a bearing surface, the light guide plate is positioned on the bearing surface, and the pasting structure is connected with the light guide plate to the frame.

2. The backlight module of claim 1, wherein a distance between the first material layer and the carrying surface is less than a distance between the second material layer and the carrying surface.

3. The backlight module of claim 1, further comprising:

the reflecting element is arranged on the bearing surface, corresponds to a second area on the bottom surface, which is adjacent to the light incident side, and is positioned between the light incident side and the first area.

4. The backlight module of claim 2, wherein the paste structure has a first thickness, the reflective element has a second thickness, and the first thickness is greater than the second thickness.

5. The backlight module of claim 1, wherein the adhesive structure is adhered to the carrying surface.

6. The backlight module of claim 1, wherein the bearing surface of the frame is a reflective surface.

7. The backlight module of claim 1, wherein the first material layer has a third thickness, the second material layer has a fourth thickness, and the fourth thickness is greater than the third thickness.

8. The backlight module of claim 7, wherein a ratio of the third thickness to the fourth thickness is no more than one third.

9. The backlight module of claim 1, wherein the paste structure comprises:

the first adhesive layer is used for connecting the first material layer and the second material layer to the bottom surface of the light guide plate; and

and the second adhesive layer is connected with the first material layer and the second material layer to the bearing surface of the frame.

10. The backlight module of claim 1, wherein the paste structure is formed by stacking the first material layer and the second material layer in a flush manner.

11. The backlight module of claim 1, wherein an edge of the pasting structure and an edge of the light guide plate away from the light incident side are flush.

12. The backlight module of claim 1, wherein the distribution area of the pasting structure on the carrying surface exceeds the distribution area of the light guide plate on the carrying surface.

13. A display device, comprising:

a display panel; and

the backlight module according to any one of claims 1 to 12, wherein the display panel is disposed on the backlight module,

and the light guide plate comprises a light-emitting surface facing the display panel, the bottom surface is opposite to the light-emitting surface, and the light-entering side is connected with the light-emitting surface and the bottom surface.