TW201317678A - Backlight module and display device - Google Patents

Abstract

A backlight module includes a light guide plate, a light emitting device and a frame. The light guide plate has a first surface, a second surface respects to the first surface and multiple side surfaces connect with the first surface and the second surface. One of the side surfaces is the light incident surface. The light emitting device is located nearby the light incident surface and is suitable for emitting the light from the light incident surface to the light guide plate. The frame surrounds with the light guide plate and has multiple light absorbing surfaces facing to the side surface. Frame has a light extinction structure on its light absorbing surfaces; some light is suitable for emitting from the side surfaces of the light guide plate and enters the light extinction structure.

Description

Backlight module and display device

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

In recent years, with the vigorous development of display technology, liquid crystal displays have been widely used in daily life, and liquid crystal displays have been widely used in LCD TVs, personal computer monitors, and notebook computer screens. The liquid crystal display mainly consists of a backlight module and a liquid crystal display panel. The backlight module is mainly composed of a light-emitting element, a light guide plate, a diffusion sheet, a cymbal piece and an external machine member, and is used to provide a surface light source required for the liquid crystal display panel to display. The backlight module can be divided into a side light type or a direct light type according to the light source light output mode. The side-emitting light is suitable for applications with a large thickness limit such as a notebook computer or a tablet computer, and the direct-lit light is suitable for use on a large-sized display.

The backlight module is provided as a light source, and the brightness and uniformity of the backlight are important specifications of the backlight module. However, in the backlight module, there is often light passing through the side of the light guide plate and hitting the plastic frame, which causes light leakage from the reflective frame of the plastic frame, which affects the performance of the backlight module, and is currently a problem solved by the industry. Known techniques often avoid light leakage by attaching black or light absorbing tape to the light leak. However, the foregoing practices relatively increase the cost of raw materials and the number of working hours, and are difficult to rework.

The invention provides a backlight module, which can effectively avoid internal light leakage and provide a good backlight.

The invention provides a backlight module, which comprises a light guide plate, a light-emitting element and a bearing frame. The light guide plate has a first surface, a second surface opposite to the first surface, and a plurality of sides connecting the first surface and the second surface, wherein one of the sides is a light incident surface. The illuminating element is disposed beside the light incident surface, and the illuminating element is adapted to emit a light from the light incident surface into the light guide plate. The carrying frame surrounds the light guide plate, and the carrying frame has a plurality of light absorbing surfaces facing the side. The carrier frame has a matte structure on the light absorbing surface, and part of the light is adapted to be emitted from the side surface and enter the light extinction structure.

In an embodiment of the invention, the matte structure of the backlight module includes a plurality of recessed holes.

In an embodiment of the invention, the recess of the backlight module has a depth of 0 to 5 mm.

In an embodiment of the invention, the recessed holes of the backlight module have a distribution density of 0.1 to 1.

In an embodiment of the present invention, the side surface of the backlight module includes a first side surface and a second side surface connected to the light surface, and the first side surface is opposite to the second side surface and faces the first side surface and the second side surface. The distribution density of the recessed holes decreases in a direction away from the light emitting elements.

In an embodiment of the present invention, the side surface of the backlight module includes a first side surface and a second side surface connected to the light surface, and the first side surface is opposite to the second side surface and faces the first side surface and the second side surface. The area of the distribution area of the recessed holes on their respective light absorbing surfaces is decremented in a direction away from the light emitting elements.

In an embodiment of the present invention, the side surface of the backlight module includes a first side surface and a second side surface connected to the light surface, and the first side surface is opposite to the second side surface and faces the first side surface and the second side surface. The depth of each of the recesses decreases as it moves away from the light-emitting elements.

In an embodiment of the present invention, a side surface of the backlight module includes a third side opposite to the light incident surface, and a distribution density of the concave hole in a central portion facing the third side is smaller than a peripheral area facing the third side surface. The distribution density of the recessed holes.

In an embodiment of the present invention, a side surface of the backlight module includes a third side opposite to the light incident surface, and a concave area of the central portion facing the third side has a smaller area of the distribution area on the corresponding light absorbing surface. The area of the distribution area of the concave hole facing the peripheral portion of the third side on the light absorbing surface.

In an embodiment of the present invention, a side surface of the backlight module includes a third side opposite to the light incident surface, and a depth of each of the concave holes facing the central portion of the third side is smaller than a peripheral area facing the third side. The depth of each recess.

In an embodiment of the invention, the recess of the backlight module includes a plurality of tapered holes.

In an embodiment of the invention, the apex angle of the tapered hole of the backlight module is about 1 to 10 degrees.

In an embodiment of the present invention, the side surface of the backlight module includes a first side surface and a second side surface connected to the light surface, and the first side surface is opposite to the second side surface and faces the first side surface and the second side surface. The apex angle of the tapered hole increases in a direction away from the light emitting element.

In an embodiment of the present invention, a side surface of the backlight module includes a third side opposite to the light incident surface, and a apex angle of each of the tapered holes facing the central portion of the third side is larger than a periphery facing the third side The apex angle of each tapered hole in the area.

In one embodiment of the present invention, the recess of the backlight module has a first cross-sectional area adjacent to the light absorbing surface and a second cross-sectional area that is relatively far from the light absorbing surface, and the first cross-sectional area is greater than the second cross-sectional area.

In an embodiment of the invention, the recessed hole of the backlight module has a plurality of microstructures on the wall of the hole.

The present invention further provides a display device using the foregoing backlight module, which comprises the backlight module as described above and a display panel. The display panel is disposed on the carrying frame of the backlight module to receive the backlight provided by the backlight module, thereby displaying a picture.

The above described features and advantages of the present invention will be more apparent from the following description.

1 is a display device of an embodiment of the present invention. 2 is a schematic diagram of a backlight module according to an embodiment of the present invention. Figure 3 is a cross-sectional view taken along line I-I' of Figure 2 of an embodiment of the present invention. Referring to FIG. 1 to FIG. 3 simultaneously, the display device 1000 is composed of a backlight module 100 and a display panel 200. The backlight module 100 includes a light guide plate 110 , a light emitting component 120 , and a carrier frame 130 . The display panel 200 is disposed on the carrying frame 130 of the backlight module 100. The light guide plate 110 has a first surface 112 and a second surface 114 opposite to the first surface 112. The first surface 112 and the second surface 114 have a light incident surface 116 adjacent to the two side surfaces 115 of the light incident surface 116 and the side surface 117 with respect to the light incident surface. The light-emitting element 120 is disposed adjacent to the light-incident surface 116, and the light-emitting element 120 is adapted to emit a light L from the light-incident surface 116 into the light guide plate 110.

4 is a cross-sectional view of the carrier frame 130 taken along line I-I' of FIG. 2. Referring to FIG. 2 and FIG. 4 simultaneously, the carrier frame 130 surrounds the periphery of the light guide plate 110, and the carrier frame 130 has a plurality of light absorption surfaces 135 and 137 facing the sides 115 and 117. In this embodiment, the matting structures 145 and 147 are respectively formed on the light absorbing surfaces 135 and 137 of the carrying frame 130, so that part of the light L emitted from the side surfaces 115 and 117 of the light guiding plate 110 enters the matting structures 145 and 147, and is cut.

The matting structures 145 and 147 employed in this embodiment may employ any design having a matting effect. As shown in FIG. 4, for example, concave holes may be formed on the light absorbing surfaces 135 and 137 of the bearing frame 130, and conditions such as shape, depth, aperture, distribution position, distribution density, and the like of the concave holes may be adjusted to meet relevant requirements. For example, the depth of the recessed hole is, for example, 0 to 5 mm, and the density of the recessed hole is between 0.1 and 1. Here, the distribution density is defined as the percentage of the area occupied by the recessed hole in the unit area of the light absorbing surface.

A number of possible extinction structures are listed below for illustration. 5 through 14 are partial cross-sectional views of various different matting structures that may be employed in the foregoing embodiments.

First, FIG. 5A illustrates the formation of a tapered hole 510 on the light absorbing surface 135 or 137 of the carrier frame 130 as a matte structure 145 or 147 for absorbing a portion of the light L emitted from the side surface 115 or 117 of the light guide plate 110. In addition, as shown in FIG. 5B, each tapered hole 510 has a first cross-sectional area A1 along the a-a' line segment at the opening adjacent to the light absorbing surface 135 or 137, and each tapered hole 510 is relatively far from the light absorbing surface 135. The bottom of 137 or 137 has a second cross-sectional area A2 along the line bb', wherein the first cross-sectional area A1 is greater than the second cross-sectional area A2. As such, the light L is easily entered into the tapered hole 510 from the opening of each tapered hole 510, and is cut after being repeatedly reflected in the tapered hole 510. Here, the apex angle θ of the tapered hole 510 can be adjusted according to actual needs. For example, in an embodiment, the apex angle θ of the tapered hole 510 is between 1 and 10 degrees.

FIG. 6 illustrates another matte structure including a tapered aperture 610 on the light absorbing surface 135 or 137 of the carrier frame 130 to serve as a matte structure 145 or 147. Compared with the tapered hole 510 of FIG. 5, the hole wall 612 of the tapered hole 610 of the embodiment further has a microstructure 614, which helps to improve the number of reflections of the light L in the tapered hole 610, thereby achieving better performance. Extinction effect. The tapered hole 610 having the microstructure 614 can be fabricated by a method such as mold stenciling.

Of course, the present invention does not limit the type of the recessed hole formed, and the structure which can achieve the same or similar matting effect as the tapered hole 510 or 610 of the foregoing embodiment, such as a semicircular hole, a square tapered hole or a trapezoidal hole. It can be used as the matte structure of the present invention.

On the other hand, the intensity of the light emitted from the side of the light guide plate may vary with the position. Therefore, the brightness of the matte structure on the light absorbing surface can be adjusted to provide uniform light output.

FIG. 7 illustrates a plurality of recessed holes 710 formed on the light absorbing surface 135 of the carrier frame 130 as the matte structure 145. In the present embodiment, the distribution density of the recessed holes 710 decreases as moving away from the light-emitting elements 120. In other words, the area near the light-emitting element 120 is distributed with dense recessed holes 710, so that a better matting effect can be provided than other areas.

FIG. 8 illustrates forming a plurality of recessed holes 810 on the light absorbing surface 135 of the carrier frame 130 as the matte structure 145. In the present embodiment, the distribution area S1 of the recessed holes 810 decreases as moving away from the light-emitting elements 120. In other words, the area close to the light-emitting element 120 is distributed by the recessed holes 810 having a larger area, so that a better matting effect can be provided than other areas.

In addition to the distribution density and area of the recessed holes, the following is a discussion of the depth of the recessed holes and the angle of the apex angle of the recessed holes. In order to make the illustration simple and clear, the following FIGS. 9 and 10 are all shown in the perspective shown in FIG. 2.

FIG. 9 illustrates that a plurality of recessed holes 910 are formed on the light absorbing surface 135 of the carrier frame 130 as the matte structure 145. In the present embodiment, the depth D1 of the recess 910 decreases as it moves away from the light emitting element 120. In other words, in the region close to the light-emitting element 120, since the depth D1 of the recessed hole 910 is deep, a preferable matting effect can be provided.

FIG. 10 illustrates that a plurality of recessed holes 1010 are formed on the light absorbing surface 135 of the carrier frame 130 as the matte structure 145. In the present embodiment, the apex angle θ1 of the recessed hole 1010 is increased as moving away from the light emitting element 120. In other words, in the region near the light-emitting element 120, the apex angle θ1 of the recessed hole 1010 is small to provide a better matting effect.

In contrast to the various designs of the matte structure 145 on the light absorbing surface 135 shown in FIGS. 7-10, the following FIGS. 11-14 further illustrate the extinction structure 147 formed on the light absorbing surface 137 with respect to the light incident surface 116. Several design options.

First, FIG. 11 illustrates that a plurality of recessed holes 1110 are formed on the light absorbing surface 137 of the carrier frame 130 as the extinction structure 147. In the present embodiment, the distribution density of the recessed holes 1110 is increased from the central portion of the light absorbing surface 137 toward the peripheral region. In other words, in the peripheral region near the light absorbing surface 137, the dense recessed holes 1110 are distributed to allow the light absorbing surface 137 to have a better matting effect.

FIG. 12 illustrates that a plurality of recessed holes 1210 are formed on the light absorbing surface 137 of the carrier frame 130 as the matte structure 147. In the present embodiment, the distribution area S2 of the recessed holes 1210 is increased from the central area of the light absorbing surface 137 toward the peripheral area. In other words, in the peripheral region near the light absorbing surface 137, the large-area concave hole 1210 allows the light absorbing surface 137 to have a better matting effect.

In addition to the distribution density and area of the recessed holes, the following is a discussion of the depth of the recessed holes and the angle of the apex angle of the recessed holes. In order to make the illustrations simple and clear, the following FIGS. 13 and 14 are all shown in the perspective shown in FIG. 2.

FIG. 13 illustrates that a plurality of recessed holes 1310 are formed on the light absorbing surface 137 of the carrier frame 130 as the extinction structure 147. In the present embodiment, the depth D2 of the recessed hole 1310 is increased from the central portion of the light absorbing surface 137 toward the peripheral region. In other words, the depth D2 of the recessed hole 1310 is deeper in the peripheral region near the light absorbing surface 137, so that the light absorbing surface 137 can have a better matting effect.

FIG. 14 illustrates that a plurality of recessed holes 1410 are formed on the light absorbing surface 137 of the carrier frame 130 as the matte structure 147. In the present embodiment, the apex angle θ2 of the recessed hole 1410 decreases from the central portion of the light absorbing surface 137 toward the peripheral region. In other words, in the peripheral region near the light absorbing surface 137, the apex angle θ2 of the recessed hole 1410 is small, so that the light absorbing surface 137 can have a better matting effect.

In summary, the backlight module of the present invention provides a matting structure on the light absorbing surface of the side of the light guide plate facing the light guide plate, absorbs the light emitted from the side surface of the light guide plate, and reduces the light on the side of the carrying frame and the light guide plate. Light leakage caused by reflection between. The display device to which the backlight module is applied can have good display quality.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the invention, and any one of ordinary skill in the art can make some modifications and refinements without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims.

1000. . . Display device

100. . . Backlight module

200. . . Display panel

110. . . Light guide

112. . . First surface

114. . . Second surface

115. . . side

116. . . Glossy surface

117. . . side

120. . . Light-emitting element

L. . . Light

130. . . Carrier frame

135. . . Absorbing surface

137. . . Absorbing surface

145. . . Extinction structure

147. . . Extinction structure

510. . . Conical hole

A1. . . First cross-sectional area

A2. . . Second cross-sectional area

θ. . . Top angle

610. . . Conical hole

612. . . hole wall

614. . . microstructure

710. . . Concave hole

810. . . Concave hole

S1. . . Distribution area

910. . . Concave hole

D1. . . depth

1010. . . Concave hole

Θ1. . . Corner angle

1110. . . Concave hole

1210. . . Concave hole

S2. . . Distribution area

1310. . . Concave hole

D2. . . depth

1410. . . Concave hole

Θ2. . . Corner angle

1 is a display device of an embodiment of the present invention.

2 is a schematic diagram of a backlight module in accordance with an embodiment of the present invention.

Figure 3 is a cross-sectional view of the backlight module of Figure 2 taken along line I-I'.

4 is a cross-sectional view of the carrier frame of the backlight module of FIG. 2 taken along line I-I'.

5 through 14 are partial cross-sectional views of various different matting structures that may be employed in the foregoing embodiments.

100. . . Backlight module

110. . . Light guide

112. . . First surface

115. . . side

116. . . Glossy surface

117. . . side

120. . . Light-emitting element

130. . . Carrier frame

Claims (17)

A backlight module includes: a light guide plate having a first surface, a second surface opposite to the first surface, and a plurality of sides connecting the first surface and the second surface, wherein one of the sides a light-emitting element disposed adjacent to the light-incident surface, the light-emitting element is adapted to emit a light from the light-incident surface into the light guide plate; and a carrier frame surrounding the light guide plate, and the carrier frame Having a plurality of light absorbing surfaces facing the sides, the carrier frame has a light extinction structure on the light absorbing surfaces, and the light is adapted to be emitted from the side surfaces of the light guide plate and enter the light extinction structure . The backlight module of claim 1, wherein the matte structure comprises a plurality of recessed holes. The backlight module of claim 2, wherein each of the recessed holes has a depth of 0 to 5 mm. The backlight module of claim 2, wherein the recessed holes have a distribution density of 0.1 to 1. The backlight module of claim 2, wherein the side surfaces comprise a first side and a second side connected to the light incident surface, the first side is opposite to the second side, and facing the first The distribution densities of the recesses on one side and the second side decrease in a direction away from the light emitting element. The backlight module of claim 2, wherein the side surfaces comprise a first side and a second side connected to the light incident surface, the first side is opposite to the second side, and facing the first The area of the distribution area of the concave holes of one side and the second side on the corresponding light absorbing surface thereof decreases in a direction away from the light emitting element. The backlight module of claim 2, wherein the side surfaces comprise a first side and a second side connected to the light incident surface, the first side is opposite to the second side, and facing the first The depth of each of the recesses on one side and the second side decreases in a direction away from the light emitting element. The backlight module of claim 2, wherein the side surfaces comprise a third side opposite to the light incident surface, and the recessed holes facing the central portion of the third side have a distribution density smaller than that of the surface The distribution density of the recessed holes in the peripheral region of the third side. The backlight module of claim 2, wherein the side surfaces include a third side opposite to the light incident surface, and the recesses facing the central portion of the third side are corresponding thereto The area of the distribution area on the light absorbing surface is smaller than the area of the distribution area of the concave holes on the light absorbing surface facing the peripheral area of the third side. The backlight module of claim 2, wherein the side surfaces include a third side opposite to the light incident surface, and the depth of each of the recessed holes facing the central portion of the third side is smaller than The depth of each of the recessed holes in the peripheral region of the third side. The backlight module of claim 2, wherein the recessed holes comprise a plurality of tapered holes. The backlight module of claim 11, wherein the apex angle of each of the tapered holes is 1 to 10 degrees. The backlight module of claim 11, wherein the side surfaces include a first side and a second side that are connected to the light incident surface, the first side is opposite to the second side, and faces the first The apex angles of the tapered holes of one side and the second side increase in a direction away from the light emitting element. The backlight module of claim 11, wherein the side surfaces comprise a third side opposite to the light incident surface, and a apex angle of each of the tapered holes facing the central portion of the third side is greater than An apex angle of each of the tapered holes facing the peripheral region of the third side. The backlight module of claim 2, wherein each of the recessed holes has a first cross-sectional area adjacent to the light absorbing surface and a second cross-sectional area relatively far from the light absorbing surface, and the first cross-sectional area is greater than The second cross-sectional area. The backlight module of claim 2, wherein each of the recessed holes has a plurality of microstructures on the wall of the hole. A display device, comprising: the backlight module according to any one of claims 1 to 16; and a display panel disposed on the carrier frame.