TW201418842A - Display device and back light module thereof - Google Patents

Abstract

A back light module includes a light guide plate, a light source, and a shielding tape. The light guide plate has a light incident surface and a light-emitting surface adjacent to the light incident surface. The light source faces the light incident surface. The shielding tape disposes on the light-emitting surface. The shielding tape is adjacent to the light incident surface. The shielding tape comprises a base layer and a glue layer. The base layer disposes above the glue layer. The base layer has a first side edge near the light source and a second side edge far away from the light source. The glue layer has a third side edge near the light source and a forth side edge far away from the light source. The third side edge and the first side edge keep in a first distance. The forth side edge and the second side edge keep in a second distance.

Description

Display device and backlight module thereof

The invention relates to an electronic device, in particular to a display device with a backlight module and a backlight module thereof.

For the rapid advancement of the multimedia society, most of them benefit from the rapid development of semiconductor components or display devices. In terms of display elements, cathode display tubes (or cathode tubes, Cathode Ray Tubes, CRTs) have consistently dominated the display market due to their superior display quality and economy. However, CRTs have the problem of excessive volume and excessive energy consumption. For high image quality, low power consumption, thin mass production, low voltage driving, small size, etc., CRT-type displays obviously cannot achieve this requirement. In view of this, liquid crystal display (LCD) will have great advantages, and LCD has been widely used in small and medium-sized portable TVs, video phones, video recorders, notebook computers, and tables. Top-size displays, tablets, and projection color TVs.

Taking a liquid crystal display as an example, it includes a backlight module. The backlight module comprises a light guide plate and a light source, and the light source surface is arranged on the light incident surface of the light guide plate. In addition, in order to avoid light leakage, a light shielding layer is further disposed at the edge of the light-emitting surface of the light guide plate to prevent light leakage from the light-emitting surface adjacent to the edge of the light-incident surface.

However, since the light shielding layer adheres to the light emitting surface of the light guide plate through the adhesive layer, when the light of the light source is transmitted to the light emitting surface of the light guide plate to which the adhesive layer is adhered, the energy of the light is absorbed by the adhesive layer and consumed. Moreover, the adhesive layer may also be overflowed by the edge of the light shielding layer due to tolerance deviation and temperature deformation, thereby causing uneven brightness. The problem. As a result, the optical efficiency of the backlight module will be reduced.

The invention provides a display device and a backlight module thereof, thereby improving the optical efficiency of the backlight module.

The backlight module disclosed in the present invention comprises a light guide plate, a light source and a light shielding sheet. The light guide plate has adjacent light incident surfaces and light exit surfaces. The light source faces the light entrance surface. The light shielding film is disposed on the light emitting surface, and the light shielding film is adjacent to the light incident surface. The light shielding sheet has a base layer and a glue layer. The base layer is above the glue layer, the base layer having a first side adjacent the light source and a second side away from the light source. The glue layer has a third side adjacent the light source and a fourth side away from the light source. The third side maintains a first spacing from the first side, and the fourth side and the second side maintain a second spacing.

The display device disclosed in the present invention comprises a carrier board, a backlight module, an optical film and a display panel. The backlight module is disposed on the carrier board, and the backlight module comprises a light guide plate, a light source and a light shielding film. The light guide plate has adjacent light incident surfaces and light exit surfaces. The light source faces the light entrance surface. The light shielding film is disposed on the light emitting surface, and the light shielding film is adjacent to the light incident surface. The light shielding sheet has a base layer and a glue layer. The base layer is above the glue layer, the base layer having a first side adjacent the light source and a second side away from the light source. The glue layer has a third side adjacent the light source and a fourth side away from the light source. The third side maintains a first spacing from the first side, and the fourth side and the second side maintain a second spacing. The optical film is stacked on the light guide plate of the backlight module. The display panel is located on the optical film.

According to the display device and the backlight module thereof disclosed in the above, the opposite side edges of the adhesive layer are respectively spaced apart from the opposite side edges of the base layer. In this way, the area of the glue layer attached to the light guide plate can be reduced to reduce the absorption of light energy by the glue layer. The problem of depletion consumption. Moreover, the phenomenon that the rubber layer is overflowed due to tolerance deviation or temperature deformation can be avoided to avoid the problem of uneven brightness.

The features, implementations, and utilities of the present invention are described in detail below with reference to the drawings.

1 and 2, FIG. 1 is a cross-sectional view showing a structure of a display device according to an embodiment of the present invention, and FIG. 2 is a bottom view showing a structure of a light shielding sheet according to FIG. 1.

The display device 10 of this embodiment can be applied to a tablet computer or a liquid crystal screen, but is not limited thereto. The display device 10 includes a carrier board 11, a backlight module 20, an optical film 12, a display panel 13, and a housing 14.

The carrier board 11 may be an aluminum substrate to have good heat dissipation performance. The backlight module 20 is disposed on the carrier board 11 , and the backlight module 20 includes a light guide plate 21 , a light source 22 , and a light shielding sheet 23 .

The light guide plate 21 has adjacent light incident surfaces 211 and light exit surfaces 212. In addition, the light guide plate 21 further has a bottom surface 213. The bottom surface 213 and the light exit surface 212 are located on opposite sides of the light guide plate 21, and the bottom surface 213 faces the carrier plate 11.

The light source 22 is disposed on the carrier plate 11 and the light source 22 faces the light incident surface 211. The light emitted by the light source 22 enters the light guide plate 21 through the light incident surface 211, and the light is uniformly emitted outside the light guide plate 21 via the light exit surface 212.

In addition, in the embodiment, the backlight module 20 may further include a reflective sheet 24 disposed on the bottom surface 213 of the light guide plate 21 . In other words, the reflection sheet 24 is interposed between the carrier plate 11 and the light guide plate 21. The reflective sheet 24 is used for reflecting illumination to the bottom surface 213 Light to increase the energy of the light emitted by the light exit surface 212.

The light shielding sheet 23 is disposed on the edge of the light emitting surface 212 adjacent to the light incident surface 211. The light shielding sheet 23 has a base layer 231 and a glue layer 232. The base layer 231 is located above the glue layer 232. The base layer 231 is adhered to the light exit surface 212 by the adhesive layer 232. The base layer 231 can be a film of a dark material. For example, the base layer 231 can be a polyester film of a black material, but is not limited thereto. The base layer 231 is configured to block the light emitted from the light-emitting surface 212 near the light-incident surface 211 (ie, near the light source 22) to avoid light leakage.

The base layer 231 has a first side 2311 adjacent to the light source 22 and a second side 2312 remote from the light source 22. In this embodiment, the first side 2311 is substantially aligned with the edge of the light-emitting surface 212 adjacent to the light-incident surface 211.

The glue layer 232 has a third side 2323 adjacent to the light source 22 and a fourth side 2324 away from the light source 22. The distance W1 of the first side edge 2311 to the second side edge 2312 (i.e., the width of the base layer 231) is greater than the distance W2 of the third side edge 2323 to the fourth side edge 2324 (i.e., the width of the glue layer 232). Furthermore, the area of the base layer 231 is larger than the area of the glue layer 232 such that the glue layer 232 adheres only to the partial base layer 231, and the glue layer 232 substantially adheres to the non-edge region of the base layer 231. Further, the third side 2323 of the adhesive layer 232 maintains a first spacing D1 with the first side 2311 of the base layer 231, and the fourth side 2324 of the adhesive layer 232 maintains a second spacing from the second side 2312 of the base layer 231. D2. In this way, the area of the adhesive layer 232 attached to the light guide plate 21 can be reduced to reduce the problem that the light energy is absorbed by the adhesive layer 232 and the consumption is reduced. Moreover, by maintaining the spacing between the opposite side edges of the adhesive layer 232 and the opposite side edges of the base layer 231, the adhesive layer 232 can be prevented from overflowing from the edge of the base layer 231 due to tolerance offset or temperature deformation (so-called overflow). Glue), caused by uneven brightness and light leakage.

Moreover, in the embodiment, the first spacing D1 may be at least greater than 1 mm, the second spacing D2 may be at least greater than 0.5 mm, and the distance W1 of the first side 2311 to the second side 2312 (ie, the base layer 231 The width) can range from 3 mm to 5 mm. In this way, the occurrence of light leakage can be avoided, and the backlight module 20 has a better optical effect.

Further, the optical film 12 is stacked on the light guide plate 21 of the backlight module 20. The optical film 12 may be, for example, a diffusion sheet, a brightness enhancement sheet, or a composite film formed by stacking two or more of a diffusion sheet and a brightness enhancement sheet. The optical film 12 is stacked on the light guide plate 21 for enhancing or homogenizing the light generated by the backlight module 20 to improve the overall optical efficiency.

The frame 14 is disposed on the edge of the carrier 11 and has a laterally extending side plate to support the display panel 13 on the backlight module 20 such that the display panel 13 is located on the optical film 12 to make the optical film. The sheet 12 is interposed between the display panel 13 and the light guide plate 21 .

3 and 4, FIG. 3 is a cross-sectional view showing the structure of a display device according to another embodiment of the present invention, and FIG. 4 is a bottom view showing the structure of the light shielding sheet according to FIG. 3. Since this embodiment is similar to the embodiment of Figs. 1 and 2, only the differences will be described.

The difference between the display device 10a of the present embodiment and the first and second embodiments is that the light shielding sheet 23a of the backlight module 20a further includes a reflective layer 233. The reflective layer 233 may be, but not limited to, a film having a reflective material or a white film. The reflective layer 233 can be disposed on the base layer 231a by adhesion or printing, and the reflective layer 233 and the adhesive layer 232a are located on the same side of the base layer 231a. In addition, the base layer 231a of this embodiment The system extends above the light source 22. One end of the reflective layer 233 is aligned with the first side 2311a of the base layer 231a, and the other end of the reflective layer 233 extends toward the adhesive layer 232a to have a width W3. As such, a portion of the reflective layer 233 is positioned between the light source 22 and the light incident surface 211. Furthermore, there is a gap between the light source 22 and the light incident surface 211, and at least a portion of the reflective layer 233 is located above the gap.

In this way, the light L that would have been leaked from the gap between the light source 22 and the light incident surface 211 can be reflected back into the light surface 211 by the reflective layer 233 and enter the light guide plate 21 to increase the light recovery rate. And improve overall optical efficiency. Further, the above width W3 may be at least greater than 1 mm, which may have a better reflection effect.

The display device and the backlight module thereof according to the above embodiments are respectively spaced apart from opposite side edges of the base layer by opposite side edges of the adhesive layer. In this way, the area where the adhesive layer is attached to the light guide plate can be reduced, so as to reduce the problem that the light energy is absorbed by the adhesive layer and the consumption is reduced. Moreover, the phenomenon that the rubber layer is overflowed due to tolerance deviation or temperature deformation can be avoided to avoid the problem of uneven brightness.

While the present invention has been described above in terms of the preferred embodiments thereof, it is not intended to limit the invention, and the invention may be modified and modified without departing from the spirit and scope of the invention. The patent protection scope of the invention is subject to the definition of the scope of the patent application attached to the specification.

10‧‧‧ display device

10a‧‧‧Display device

11‧‧‧Loading board

12‧‧‧Optical diaphragm

13‧‧‧ display panel

14‧‧‧ frame

20‧‧‧Backlight module

20a‧‧‧Backlight module

21‧‧‧Light guide

211‧‧‧Into the glossy surface

212‧‧‧Glossy surface

213‧‧‧ bottom

22‧‧‧Light source

23‧‧‧Shading film

23a‧‧ ‧ shading film

231‧‧‧ grassroots

231a‧‧‧ grassroots

2311‧‧‧First side

2311a‧‧‧ first side

2312‧‧‧Second side

232‧‧‧ glue layer

232a‧‧‧ glue layer

2323‧‧‧ third side

2324‧‧‧4th side

233‧‧‧reflective layer

24‧‧‧reflector

1 is a cross-sectional view showing the structure of a display device according to an embodiment of the present invention.

Fig. 2 is a bottom view showing the structure of the light shielding sheet according to Fig. 1.

Figure 3 is a cross-sectional view showing the structure of a display device according to another embodiment of the present invention.

Fig. 4 is a bottom view showing the structure of the light shielding sheet according to Fig. 3.

10‧‧‧ display device

11‧‧‧Loading board

12‧‧‧Optical diaphragm

13‧‧‧ display panel

14‧‧‧ frame

20‧‧‧Backlight module

21‧‧‧Light guide

211‧‧‧Into the glossy surface

212‧‧‧Glossy surface

213‧‧‧ bottom

22‧‧‧Light source

23‧‧‧Shading film

231‧‧‧ grassroots

2311‧‧‧First side

2312‧‧‧Second side

232‧‧‧ glue layer

2323‧‧‧ third side

2324‧‧‧4th side

24‧‧‧reflector

Claims (15)

A backlight module includes: a light guide plate having an adjacent light incident surface and a light exiting surface; a light source facing the light incident surface; and a light shielding sheet disposed on the light emitting surface, and the light shielding sheet is adjacent to the light shielding sheet The light-shielding sheet has a base layer and a glue layer, and the glue layer is located between the base layer and the light-incident surface, the base layer has a first side adjacent to the light source and a second portion away from the light source a side layer, the glue layer has a third side adjacent to the light source and a fourth side away from the light source, the third side maintaining a first spacing from the first side, the fourth side The second side maintains a second spacing. The backlight module of claim 1, wherein the distance from the first side to the second side is greater than the distance from the third side to the fourth side. The backlight module of claim 1, wherein the base layer has an area larger than an area of the adhesive layer. The backlight module of claim 1, wherein the first pitch ranges from at least greater than 1 mm. The backlight module of claim 1, wherein the second pitch ranges from at least greater than 0.5 mm. The backlight module of claim 1, wherein the distance from the first side to the second side ranges from 3 mm to 5 mm. The backlight module of claim 1, wherein the light shielding sheet further comprises a reflective layer, the reflective layer and the adhesive layer are located on the same side of the base layer, and at least part of the reflective layer is located at the light source and the light entering Between the faces. A display device comprising: a carrier board; a backlight module disposed on the carrier board, comprising: a light guide plate having an adjacent light incident surface and a light exit surface; a light source facing the light incident surface; And a light shielding sheet disposed on the light emitting surface, wherein the light shielding sheet is adjacent to the light incident surface, the light shielding sheet has a base layer and a glue layer, and the glue layer is located between the base layer and the light incident surface, the base layer has Adjacent to a first side of the light source and a second side away from the light source, the glue layer has a third side adjacent to the light source and a fourth side away from the light source, the third side The first side maintains a first spacing, the fourth side and the second side maintain a second spacing; an optical film stacked on the light guide plate of the backlight module; and a display panel Located on the optical film. The display device of claim 8, wherein the distance from the first side to the second side is greater than the distance from the third side to the fourth side. The display device of claim 8, wherein the area of the base layer is larger than the area of the glue layer. The display device of claim 8, wherein the first pitch ranges from at least greater than 1 mm. The display device of claim 8, wherein the second pitch ranges from at least greater than 0.5 mm. The display device of claim 8, wherein the first side to the second side The range of distance is 3mm to 5mm The display device of claim 8, wherein the light shielding sheet further comprises a reflective layer, the reflective layer and the adhesive layer are on the same side of the base layer, and at least a portion of the reflective layer is located on the light source and the light incident surface. between. The display device of claim 8, further comprising a frame disposed on an edge of the carrier, the display panel being stacked on the frame.