TWI468808B - Backlight module and display apparatus using the same - Google Patents

Description

Backlight module and display device using same

The present invention relates to a light source module, and more particularly to a backlight module that can be applied to a display device and a display device using the same.

The liquid crystal display device is one of the display devices with high popularity. The liquid crystal display device mainly includes a liquid crystal display panel and a backlight module. The backlight module is used to provide a display light source required for the liquid crystal display panel.

The backlight module can be divided into a direct-lit backlight module and a side-lit backlight module, wherein the side-lit backlight module includes a light guide plate and a light-emitting component disposed beside the light-incident surface of the light guide plate. In the early technology, a cold cathode fluorescent lamp (CCFL) was usually used as a light-emitting element. In recent years, cold cathode fluorescent tubes have been gradually replaced by light emitting diodes.

In the prior art, the light-emitting diodes are usually disposed on a circuit board, and the circuit board is adhered to the bottom of the light guide plate by tape. In order to avoid light leakage, the light-emitting surface of the light-emitting diode and the light-incident surface of the light guide plate need to be accurately aligned. However, the thickness of the tape itself causes the light-emitting surface of the light-emitting diode and the light-incident surface of the light guide plate to be inaccurately aligned in the thickness direction of the light guide plate to cause light leakage, which will reduce the light utilization efficiency of the backlight module.

The invention provides a backlight module to improve light utilization efficiency.

The present invention further provides a display device for improving light utilization efficiency.

The invention provides a backlight module, which comprises a light guide plate and a light source assembly. The light guide plate has a light incident surface, and the light source assembly includes at least one light emitting element, a substrate and a glue material. The light emitting element is disposed beside the light incident surface, the substrate has a bearing surface carrying the light emitting element and a recessed portion, and the partial bearing surface is connected to the light guide plate and exposes the recessed portion. The glue material is disposed in the concave portion and adhered to the light guide plate.

In an embodiment of the invention, the substrate is a flexible circuit board.

In an embodiment of the invention, the substrate comprises a flexible substrate, a wiring layer and a protective layer. The circuit layer is disposed on the surface of the flexible substrate, the protective layer covers the circuit layer, and the bearing surface is the surface of the protective layer. The light emitting element is electrically connected to the circuit layer, and the depressed portion is formed in the circuit layer and the protective layer.

In an embodiment of the invention, the substrate comprises a flexible substrate, a first wiring layer, a first protective layer, a second wiring layer, a second protective layer, and at least one contact window connecting material. The flexible substrate has a first surface facing the opposite side and a second surface, the first wiring layer being disposed on the first surface, and the first protective layer covering the first wiring layer. The bearing surface is a surface of the first protective layer, and the light emitting element is electrically connected to the first circuit layer. The second circuit layer is disposed on the second surface, the second protective layer covers the second circuit layer, and the contact window connecting material is electrically connected to the first circuit layer and the second circuit layer.

In an embodiment of the invention, the recessed portion is formed in the first circuit layer and the first protective layer.

In an embodiment of the invention, the recessed portion includes a plurality of recesses.

In an embodiment of the invention, the number of the at least one light-emitting element is plural, and there is a gap between the adjacent two light-emitting elements, and the gap corresponds to one of the recesses.

In an embodiment of the invention, the light guide plate has a light connection The bottom surface of the surface, and the glue adheres to the bottom surface.

In an embodiment of the invention, the light guide plate has a top surface connected to the light incident surface, and the glue material is adhered to the top surface.

The present invention further provides a display device including a backlight module and a display panel, wherein the display panel is disposed above the light guide plate of the backlight module. The backlight module includes a light guide plate, a light source assembly and a glue material. The light guide plate has a light incident surface, and the light source assembly includes at least one light emitting component disposed on the side of the light incident surface and the substrate. The substrate has a bearing surface for carrying the light-emitting component and a recessed portion. The partial bearing surface is connected to the light guide plate and exposes the recessed portion. The adhesive material is disposed in the recessed portion and adhered to the light guide plate.

In an embodiment of the invention, the light guide plate has a bottom surface connected to the light incident surface, and the glue material is adhered to the bottom surface. In addition, the display device may further include a frame including a side wall surrounding the light guide plate and a support portion extending from the side wall to above the light guide plate, and the display panel is disposed on the support portion.

In an embodiment of the invention, the bearing surface is more adhered to the bottom surface of the side wall.

In an embodiment of the invention, the light guide plate further has a top surface connected to the light incident surface, the glue material is adhered to the top surface, and the substrate is located between the light emitting element and the display panel. In addition, the display device may further include a frame surrounding the light guide plate, and the substrate is further connected to the top surface of the frame.

In an embodiment of the invention, the substrate is further connected to a peripheral line region of the display panel.

In an embodiment of the invention, the display device further includes a peripheral circuit region in which the main circuit board is connected to the display panel, and the substrate is further connected to the main circuit board.

In the backlight module of the present invention, since the adhesive material for adhering the substrate to the light guide plate is disposed in the recessed portion of the substrate, the thickness of the adhesive material can be prevented from affecting the light incident surface of the light guide plate and the light exit surface of the light emitting element on the light guide plate. Pair of thickness directions Bit to prevent light leakage. Thus, the light use efficiency of the backlight module and the display device of the present invention can be improved.

The above and other objects, features and advantages of the present invention will become more <RTIgt;

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a partial cross-sectional view showing a display device in accordance with an embodiment of the present invention. Referring to FIG. 1 , the display device 100 of the embodiment includes a display panel 110 and a backlight module 200 . The backlight module 200 includes a light guide plate 210 and a light source assembly 220 , and the display panel 110 is disposed above the light guide plate 210 . The light guide plate 210 has a light incident surface 212 and a bottom surface 214 connected to the light incident surface 212. The light source assembly 220 includes at least one light emitting element 222, a substrate 224, and a glue 226. The light-emitting element 222 is disposed adjacent to the light-incident surface 212. The substrate 224 has a bearing surface 225 carrying the light-emitting element 222 and a recessed portion 227. The partial-bearing surface 225 is connected to the bottom surface 214 of the light guide plate 210, for example, and exposes the recessed portion 227. The glue 226 is disposed in the recess 227 and is adhered to the bottom surface 214 of the light guide plate 210, for example.

The display panel 110 is a non-self-luminous display panel, such as a liquid crystal display panel, and the backlight module 200 is used to provide a display light source required by the display panel 110. The light-emitting element 222 is, for example, a light-emitting diode or other point light source, and the light provided therein enters the light guide plate 210 via the light-incident surface 212, and the light guide plate 210 converts the light from the light-emitting element 222 into a surface light source. The surface light source emerges from the top surface 216 of the light guide plate 210 to serve as a display light source required for the display panel 110. An optical film 230, such as a cymbal or a diffusion film, may be disposed between the top surface 216 and the display panel 110 to evenly or brighten the surface light source. In addition, the bottom surface 214 of the light guide plate 210 can be more adhered to the reflective sheet 240 to prevent the bottom surface 214 from leaking light.

In this embodiment, the substrate 224 for carrying the light emitting element 222 is, for example, A flexible circuit board, for example, is further connected to the peripheral line region 112 of the display panel 110. However, the present invention does not limit that the substrate 224 must be connected to the peripheral line region 112 of the display panel 110. Moreover, the substrate 224 can also be a rigid substrate. In addition, a glue 120 may be adhered over the peripheral line region 112, and the glue 120 is more adhered to a portion of the substrate 224 that is connected to the peripheral line region 112.

The display device 100 further includes a frame 130. The frame 130 includes a sidewall 132 surrounding the light guide plate 210 and a support portion 134 extending from the sidewall 132 to the light guide plate 210. The display panel 110 is disposed on the support portion 134. In this embodiment, the display panel 110 is adhered to the support portion 134 by the adhesive material 140, and is adhered to the optical film 230 by the adhesive material 150. The bearing surface 225 is adhered to the bottom surface 133 of the side wall 132 by, for example, the glue material 160.

In the present embodiment, the rubber 226 disposed in the recessed portion 227 is, for example, an adhesive tape, but is not limited thereto. The thickness of the adhesive material 226 is approximately equal to the depth of the recessed portion 227, that is, the adhesive material 226 for adhering the substrate 224 and the light guide plate 210 does not protrude from the bearing surface 225 of the substrate 224, so that the bearing surface of the substrate 224 can be 225 is attached to the bottom surface 214 of the light guide plate 210 in a flat manner. In this manner, the alignment between the light-emitting surface 223 of the light-emitting element 222 and the light-incident surface 212 of the light guide plate 210 in the thickness direction D of the light guide plate 210 is not affected by the glue 226, so that light leakage can be avoided, thereby improving the embodiment. The light use efficiency of the backlight module 200 is also improved by the light use efficiency of the display device 100 of the present embodiment.

The specific embodiment of the above-described depressed portion 227 will be exemplified below with reference to the drawings, but it is not intended to limit the specific structure of the depressed portion of the present invention. 2 is a partial top plan view of a substrate and a light-emitting element of a light source assembly according to an embodiment of the invention. Referring to FIG. 1 and FIG. 2, the recessed portion 227 of the light source assembly 220 includes a plurality of recesses 228, and the number of the light-emitting elements 222 is plural, for example, and there is a gap G between adjacent two light-emitting elements 222, and each gap G Corresponding to one of the pockets 228. In other words, the position of the pocket 228 is disposed in front of the light-emitting surface 223 of the development light element 222 to reduce the light energy absorbed by the glue 226 in the pocket 228, thereby improving light utilization efficiency. In another embodiment, the recess may also be replaced by a strip-shaped groove, and the present invention does not limit the specific shape of the recess.

3 is a cross-sectional view showing a substrate of a light source unit according to an embodiment of the present invention. Referring to FIG. 3 , the substrate 224 of the present embodiment includes, for example, a flexible substrate 241 , a wiring layer 242 , and a protective layer 243 . The circuit layer 242 is disposed on the surface 244 of the flexible substrate 241, and the protective layer 243 covers the circuit layer 242, and the above-described bearing surface 225 is, for example, the surface of the protective layer 243. A light emitting element (not shown) is electrically connected to the wiring layer 242. Specifically, the protective layer 243 is provided with a pad (not shown) electrically connected to the circuit layer 242, so that the light emitting element is electrically connected to the circuit layer 242 through the pad, so that the circuit layer 242 can be used. The current is transmitted to drive the light emitting element to emit light. Further, the depressed portion 227 is formed, for example, in the wiring layer 242 and the protective layer 243.

The substrate 224 described above is a single layer circuit board, that is, the wiring layer 242 is distributed only on the single surface 244 of the flexible substrate 241. In another embodiment of the present invention, the substrate used may be a two-layer circuit board. As shown in FIG. 4, the substrate 224a includes a flexible substrate 251, a first wiring layer 252, a first protective layer 253, a second wiring layer 254, a second protective layer 255, and at least one contact window connecting material 256. The flexible substrate 251 has a first surface 257 facing the opposite side and a second surface 258. The first wiring layer 252 is disposed on the first surface 257, and the first protective layer 253 covers the first wiring layer 252. The bearing surface 225 described above is the surface of the first protective layer 253. The light-emitting element (not shown) is electrically connected to the first circuit layer 252. Specifically, the first protective layer 253 is provided with a pad (not shown) electrically connected to the first circuit layer 252, for example. The light emitting element is electrically connected to the first circuit layer 252 through the pad. The second circuit layer 254 is disposed on the second surface 258, and the second protective layer 255 covers the second line The contact layer 254 is electrically connected to the first wiring layer 252 and the second wiring layer 254 via the via 259 extending through the flexible substrate 251, the first wiring layer 252, and the second wiring layer 254. Further, the above-described depressed portion 227 is formed, for example, in the first wiring layer 252 and the first protective layer 253.

Although the adhesive material 226 adheres the substrate 224 to the bottom surface 214 of the light guide plate 210 in the embodiment of FIG. 1 , the present invention does not limit the substrate 224 to be adhered to the bottom surface 214 of the light guide plate 210 . Hereinafter, an embodiment in which the substrate 224 is adhered to other surfaces of the light guide plate 210 will be described.

Figure 5 is a partial cross-sectional view showing a display device in accordance with another embodiment of the present invention. Referring to FIG. 5, the display device 100a of the present embodiment is similar to the display device 100 of FIG. 1, and only the differences will be described below. In the display device 100a, a part of the bearing surface 225 of the substrate 224 is connected to the top surface 216 of the light guide plate 210, for example, a portion of the substrate 224 is located between the light-emitting element 222 and the display panel 110, and the glue 226 is adhered to the top surface 216. To fix the substrate 224 and the light guide plate 210. Further, the display device 100a further includes, for example, a frame 130a surrounding the light guide plate 210, and the substrate 224 is further connected to the top surface 136 of the frame 130a. The substrate 224 is adhered, for example, by a glue 170 to the top surface 136 of the frame 130a.

In the present embodiment, the adhesive material 226 of the adhesive substrate 224 and the light guide plate 210 is disposed in the recessed portion 227 of the substrate 224, so that the bearing surface 225 of the substrate 224 can be flatly attached to the top surface 216 of the light guide plate 210. In this manner, the alignment between the light-emitting surface 223 of the light-emitting element 222 and the light-incident surface 212 of the light guide plate 210 in the thickness direction D of the light guide plate 210 is not affected by the glue 226, so that light leakage can be avoided, thereby improving the embodiment. The light use efficiency of the backlight module 200a is also improved by the light use efficiency of the display device 100a of the present embodiment.

Although in FIG. 1 and FIG. 5, the substrate 224 is, for example, a main circuit board, which can be directly connected to the peripheral line region 112 of the display panel 110, the present invention does not This is limited to this. For example, as shown in FIG. 6, the display device 100b may further include a main circuit board 180 connected to the peripheral line region 112 of the display panel 110, and the substrate 224b of the light source assembly 220b is connected to the main circuit board 180, for example.

In the backlight module of the present invention, since the adhesive material for adhering the substrate to the light guide plate is disposed in the recessed portion of the substrate, the thickness of the adhesive material can be prevented from affecting the light incident surface of the light guide plate and the light emitting element. The illuminating surface is aligned in the thickness direction of the light guide plate to prevent light leakage. Thus, the light use efficiency of the backlight module and the display device of the present invention can be improved. In addition, in one embodiment, since the position of the recessed portion of the recessed portion avoids the front side of the light-emitting surface of the light developing element, the light energy absorbed by the adhesive material in the recessed hole can be reduced, thereby improving the backlight module of the present invention and The light utilization efficiency of the display device.

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

100, 100a, 100b‧‧‧ display devices

110‧‧‧ display panel

112‧‧‧ Peripheral area

120, 140, 150, 160, 170, 226‧‧‧ glue

130, 130a‧‧‧ framework

132‧‧‧ side wall

133‧‧‧ bottom

134‧‧‧Support

136‧‧‧ top surface

180‧‧‧ main board

200, 200a‧‧‧ backlight module

210‧‧‧Light guide plate

212‧‧‧Into the glossy surface

214‧‧‧ bottom

216‧‧‧ top surface

220, 220b‧‧‧Light source components

222‧‧‧Lighting elements

223‧‧‧Glossy

224, 224a, 224b‧‧‧ substrates

225‧‧‧ bearing surface

227‧‧‧Depression

228‧‧‧ recesses

230‧‧‧Optical diaphragm

240‧‧‧reflector

241, 251‧‧‧ soft substrate

242‧‧‧Line layer

243‧‧‧Protective layer

244‧‧‧ surface

252‧‧‧First line layer

253‧‧‧First protective layer

254‧‧‧Second circuit layer

255‧‧‧Second protective layer

256‧‧‧Contact window connector

257‧‧‧ first surface

258‧‧‧ second surface

259‧‧‧through hole

D‧‧‧ Thickness direction

G‧‧‧ gap

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a partial cross-sectional view showing a display device in accordance with an embodiment of the present invention.

2 is a partial top plan view of a substrate and a light-emitting element of a light source assembly according to an embodiment of the invention.

3 is a cross-sectional view showing a substrate of a light source unit according to an embodiment of the present invention.

4 is a cross-sectional view showing a substrate of a light source unit according to another embodiment of the present invention.

Figure 5 is a partial cross-sectional view showing a display device in accordance with another embodiment of the present invention.

Figure 6 is a partial cross-sectional view showing a display device in accordance with another embodiment of the present invention.

100‧‧‧ display device

110‧‧‧ display panel

112‧‧‧ Peripheral area

120, 140, 150, 160, 226‧‧‧ glue

130‧‧‧Frame

132‧‧‧ side wall

133‧‧‧ bottom

134‧‧‧Support

200‧‧‧Backlight module

210‧‧‧Light guide plate

212‧‧‧Into the glossy surface

214‧‧‧ bottom

216‧‧‧Glossy

220‧‧‧Light source components

222‧‧‧Lighting elements

223‧‧‧Glossy

224‧‧‧Substrate

225‧‧‧ bearing surface

227‧‧‧Depression

230‧‧‧Optical diaphragm

240‧‧‧reflector

D‧‧‧ Thickness direction

Claims (17)

A backlight module includes: a light guide plate having a light incident surface; and a light source assembly comprising: at least one light emitting element disposed adjacent to the light incident surface; a substrate having a bearing surface carrying the light emitting element and a recessed portion, a portion of the bearing surface is coupled to the light guide plate and exposing the recessed portion; and a rubber material disposed in the recessed portion and adhered to the light guide plate, wherein the thickness of the adhesive material is equal to the depth of the recessed portion . The backlight module of claim 1, wherein the substrate is a flexible circuit board. The backlight module of claim 2, wherein the substrate comprises: a flexible substrate; a circuit layer disposed on a surface of the flexible substrate; and a protective layer covering the circuit layer, the bearing The surface of the protective layer is electrically connected to the circuit layer, and the recess is formed in the circuit layer and the protective layer. The backlight module of claim 2, wherein the substrate comprises: a flexible substrate having a first surface facing the opposite side and a second surface a first circuit layer disposed on the first surface; a first protective layer covering the first circuit layer, the bearing surface being a surface of the first protective layer, the light emitting element being electrically connected to the first a second circuit layer disposed on the second surface; a second protective layer covering the second circuit layer; and at least one contact window connecting material electrically connecting the first circuit layer and the second circuit Floor. The backlight module of claim 4, wherein the recess is formed in the first circuit layer and the first protective layer. The backlight module of claim 1, wherein the recess comprises a plurality of recesses. The backlight module of claim 6, wherein the number of the at least one light-emitting elements is plural, and a gap is formed between the adjacent two light-emitting elements, and the gap corresponds to one of the recesses. The backlight module of claim 1, wherein the light guide plate further has a bottom surface connected to the light incident surface, and the glue material is adhered to the bottom surface. The backlight module of claim 1, wherein the light guide plate further has a top surface connected to the light incident surface, and the glue material is adhered to the top surface. A display device comprising: A backlight module includes a light guide plate and a light source assembly, the light guide plate has a light incident surface, and the light source assembly includes at least one light emitting component disposed adjacent to the light incident surface, a substrate, and a glue material, the substrate having a bearing surface carrying the light-emitting element and a recessed portion, the bearing surface being connected to the light guide plate and exposing the recessed portion, the glue material being disposed in the recessed portion and adhered to the light guide plate, wherein the adhesive material The thickness is equal to the depth of the recess; and a display panel is disposed above the light guide plate of the backlight module. The display device of claim 10, wherein the light guide plate further has a bottom surface connected to the light incident surface, and the glue material is adhered to the bottom surface. The display device of claim 11, further comprising a frame, the frame comprising a side wall surrounding the light guide plate and a support portion extending from the side wall to the light guide plate, the display panel being disposed on the support Ministry. The display device of claim 12, wherein the bearing surface is more adhered to a bottom surface of the side wall. The display device of claim 10, wherein the light guide plate further has a top surface connected to the light incident surface, the adhesive material is adhered to the top surface, and a portion of the substrate is located at the light emitting element and Between the display panels. The display device of claim 11, further comprising a frame surrounding the light guide plate, the substrate being further connected to a top surface of the frame. The display device of claim 10, wherein the substrate More connected to a peripheral line area of the display panel. The display device of claim 10, further comprising a main circuit board connected to a peripheral circuit area of the display panel, wherein the substrate is further connected to the main circuit board.