TW201405217A - Backlight module - Google Patents

Abstract

The invention relates to a backlight module, which comprises a back plate, an optical film, a lighting unit and a supporting pillar. The optical film is disposed above the back plate. The lighting unit is distributed among the back plate and between the back plate and the optical film. The lighting unit forms a centrosymmetric pattern. The supporting pillar is disposed at the center of the centrosymmetric pattern. Wherein, the supporting pillar includes a top part, a bottom part and a side part. The top part is disposed below the optical film. The bottom part is connected to the back plate. The side part is between the top part and the bottom part. The side part is surrounded by a side surface. Wherein, the lighting unit is disposed at the perpendicular bisector of a bottom line of the side surface. The invention eliminates the shading which is caused by a prior supporting pillar disposed in a backlight module. And the invention decreases the cost of manufacturing.

Description

Backlight module

The present invention relates to a backlight module, and more particularly to a direct type backlight module.

The existing liquid crystal display technology is generally applied to portable electronic products such as notebook computers, mobile phones, digital cameras, digital cameras, personal digital assistants (PDAs) and the like. In addition to these smaller portable electronic products, the recent large-size LCD panel manufacturing technology has matured. For example, a desktop liquid crystal display has replaced a cathode ray tube (CRT, also known as a "image tube") display. In terms of TV products, LCD TVs have replaced traditional video tube TVs with their compact size and clear picture. The liquid crystal panel is the most critical display component in the field, but it does not emit light by itself, and it is necessary to display an image by means of a backlight. Many backlight technologies exist today, and in large-size liquid crystal display products of more than 20 inches, a direct-lit backlight module is often used as a backlight of the liquid crystal panel.
The direct type backlight module has the advantages of high cost performance and good optical stability. And due to the rapid development of light emitting diodes (LEDs) in recent years, the light-emitting units used in the direct-lit backlight modules have been generally changed from cold cathode fluorescent tubes (CCFLs) to light-emitting units. Diode. The basic structure of the direct-lit backlight module includes a back plate disposed at the bottom of the backlight module, a light-emitting diode disposed on the back plate, and an optical film disposed on the top of the backlight module (eg, a diffusion plate, a diffusion sheet, a prism sheet or the like) and a support column disposed between the back sheet and the optical film. The role of the support column is to provide a certain height of the light mixing space for the light-emitting diode, thereby obtaining a uniform surface light source.
In the prior art, the support column of the direct type backlight module is accustomed to a white plastic material and a conical structure. Referring to FIG. 1, FIG. 1 is a schematic diagram showing the optical principle of the light-emitting unit and the support column of the prior art. The support column 120 of the white conical structure may generate the shadow 112 by blocking part of the light 111 of the light-emitting unit 110, which will seriously affect the optical uniformity and the visual effect of the liquid crystal panel. A common method for solving the shadow caused by the support column is to reduce the influence of the shadow on the image by increasing the number of optical films (such as diffusion plates, diffusion sheets, prism sheets, etc.). This method has the following disadvantages:
First, increasing the number of optical films increases the cost of the backlight module;
Second, increasing the number of optical films reduces the overall brightness of the backlight module.
From this point of view, in the existing liquid crystal display and television market, it is urgent to develop a backlight module that not only eliminates shadow but also has low cost.

In view of this, the object of the present invention is to provide a backlight module in order to eliminate the shadow caused by the support column and reduce the production cost.

To achieve the above object, the present invention provides a backlight module including a back plate, an optical film, a light emitting unit, and a support column. The optical film is located above the back plate, and the light emitting unit is disposed on the back plate and located between the back plate and the optical film. The light emitting unit forms a central symmetrical pattern, and the supporting column is located at the center of the central symmetrical figure. Wherein, the support column comprises a top portion, a bottom portion and a side portion, the top portion is located below the optical film, the bottom portion is connected to the back plate, and the side portion is sandwiched between the top portion and the bottom portion. The side portion is surrounded by a side surface, wherein the light emitting unit is located on a vertical line of the bottom side of the side surface.

In an embodiment of the invention, the support column of the backlight module includes a transparent material.

In an embodiment of the invention, the transparent material of the support post has a light transmittance equal to or greater than 50%.

In an embodiment of the invention, the transparent material of the support column is selected from the group consisting of polymethyl methacrylate (PMMA), polycarbonate (PC), nylon (PA), and polypropylene (polypropylene). , PP), polystyrene (PS), glass, and the like, or any combination thereof.

In an embodiment of the invention, the top of the support column has a spherical crown, and the spherical crown and the side portion have a smooth transition connection.

In an embodiment of the invention, the bottom of the support column has a hook, and the back plate is provided with a positioning hole, and the hook passes through the positioning hole and is fastened to the periphery of the positioning hole.

In an embodiment of the invention, the bottom of the support column further has a baffle, and a peripheral edge of the positioning hole further extends with a baffle corresponding to the baffle, and the baffle and the baffle are matched with each other.

In an embodiment of the invention, the top end of the baffle is connected to the side of the support column, and the bottom end of the baffle is connected to the hook.

In an embodiment of the invention, the baffle and the hook are crossed on the projection surface.

In an embodiment of the invention, the bottom of the support column further has a chassis, the hook is located below the chassis, and the chassis is above the back plate.

The backlight module of the present invention uses a light-emitting unit of a backlight module to form a central symmetric pattern distribution. The support column is made of a transparent material and is located at the center of the central symmetric figure, and the light-emitting units are respectively located in the bottom side of the side of the support column. On the vertical line, the light generated by the light-emitting unit can penetrate the support column more efficiently, eliminating or reducing the shadow formed by the support column in the backlight module, and relatively reducing the production cost.

In order to make the objects, features, and advantages of the present invention more readily understood by those of ordinary skill in the art, the following description of the preferred embodiments and the accompanying drawings.

Referring to FIG. 2 to FIG. 6 , FIG. 2 is a cross-sectional view of a backlight module according to a preferred embodiment of the present invention, and FIG. 3 is another embodiment of a backlight module according to a preferred embodiment of the present invention. FIG. 4 is a partial bottom view of a backlight module according to a preferred embodiment of the present invention, and FIG. 5 is a partial schematic view of a support column according to a preferred embodiment of the present invention. FIG. A top view of a central symmetrical figure in accordance with a preferred embodiment of the present invention. 2 is an example of a cross section of the A-A region shown in FIG. 4, and FIG. 3 is an example of a cross section of the B-B region shown in FIG.

The backlight module 200 includes a light emitting unit 210, a support post 220, a back plate 230, and an optical film 240. The optical film 240 is disposed above the back plate 230, and the light emitting unit 210 is disposed on the back plate 230 and between the back plate 230 and the optical film 240. The light emitting unit 210 is a light emitting diode, but is not limited thereto. The light-emitting unit 210 forms a central symmetrical pattern, and the support column 220 is located at the center of the central symmetrical pattern. As shown in FIG. 6, in the embodiment, the light-emitting units 210 are arranged in groups of four and arranged in a square, and the light-emitting unit 210 is located in a square. The corner points and the two sides form a diagonal line, and the center of the central symmetrical pattern is the intersection point of the diagonal lines, and the support column 220 is disposed at the center. Further, the support post 220 includes a top portion 221, a bottom portion 222 and a side portion 223. The top portion 221 is located below the optical film 240 and abuts the optical film 240. The bottom portion 222 is connected to the back plate 230, and the side portion 223 is sandwiched between the top portion 221 and the top portion 223. Between the bottoms 222. The side portion 223 is surrounded by four side faces 2231, so the side portion 223 is prismatic, and the light emitting unit 210 is located on the mid-perpendicular line of the bottom side of the side surface 2231.

Preferably, the support post 220 is made of a transparent material, and the transmittance of the transparent material is substantially equal to or greater than 50%. The transparent material may be selected from any one of polymethyl methacrylate (PMMA), polycarbonate (PC), nylon (PA), polypropylene (PP), polystyrene (PS), and glass, or combination.

Please refer to FIG. 9 at the same time. FIG. 9 is a schematic diagram showing the optical principle of the light-emitting unit and the support column according to a preferred embodiment of the present invention. The support column 220 is made of the above-mentioned material, and is designed correspondingly to each side surface 2231 and facing the structure of the light-emitting unit 210, thereby facilitating the penetration of light, thereby eliminating or reducing the shadow caused by the support column 220.

The top portion 221 of the support column 220 has a spherical cap 2211. As shown in FIG. 5, a smooth transition connection between the spherical cap 2211 and each side 2231 of the side portion 223, in other words, a connecting portion between the side surface 2231 and the spherical cap 2211. Has a progressive curvature change.

The bottom of the support column 220 has a hook 2221, a baffle 2222 and a chassis 2223. The top end of the baffle 2222 is connected to the chassis 2223, the bottom plate 2223 is connected to the side portion 223 of the support column 220, and the bottom end of the baffle 2222 is connected with the hook 2221. The baffle 2222 and the hook 2221 are intersected on the projection surface, as shown in FIG. Show. The back plate 230 is provided with a positioning hole 231. The hook 2221 and the positioning hole 231 correspond to each other. The peripheral edge of the positioning hole 231 further extends with a hole 232 corresponding to the baffle 2222. The hook 2221 can pass through the positioning hole 231 and be fastened to the periphery of the positioning hole 231, and the chassis 2223 is placed above the back plate 230. Thus, the hook 2221 and the bottom plate 2223 cooperate to fix the support column 220 to the support post 220. The center of the central symmetrical figure. In addition, the baffle 2222 and the baffle 232 are mated with each other to prevent the support post 220 from rotating, so that the side surface 2231 can be fixed to the ground unit 210.

Please refer to FIG. 7. FIG. 7 is a top view of a center symmetrical figure according to another preferred embodiment of the present invention. The light-emitting unit 210A is a set of six-group symmetrical hexagonal patterns. The support column 220A is located at the center and is a hexagonal prism or a prismatic structure. The support column 220A has six sides 2231A, and each side 2231A faces each of the lights. Unit 210A.

Please refer to FIG. 8. FIG. 8 is a top view of a center symmetrical figure according to still another preferred embodiment of the present invention. The light-emitting units 210B are in a group of four to form a central symmetric pattern of parallelogram patterns. The support pillars 220B are located at the center and are quadrangular prisms or prismatic structures. The support pillars 220B have four sides 2231B, and each side surface 2231B faces each Light emitting unit 210B.

In summary, the present invention is a backlight module that uses a light-emitting unit of a backlight module to form a centrally symmetric pattern distribution. The support column is made of a transparent material and is located at the center of the center-symmetric figure, and the light-emitting units are respectively located at the side of the support column. The vertical line on the side allows the light generated by the light-emitting unit to penetrate the support column more efficiently, eliminating the shadow formed by the support column in the backlight module, and relatively reducing the production cost.

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 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.

<知知>

110. . . Light unit

111. . . Light

112. . . shadow

120. . . Support column

<present invention>

200. . . Backlight module

210, 210A, 210B. . . Light unit

211. . . Light

220, 220A, 220B. . . Support column

221. . . top

2211. . . Ball crown

222. . . bottom

2221. . . The hook

2222. . . Baffle

2223. . . Chassis

223. . . Side

2231, 2231A, 2231B. . . side

230. . . Backplane

231. . . Positioning hole

232. . . Barrier

240. . . Optical diaphragm

FIG. 1 is a schematic diagram showing the optical principle of a light-emitting unit and a support column of the prior art.

FIG. 2 is a cross-sectional view showing a backlight module according to a preferred embodiment of the present invention.

FIG. 3 is a cross-sectional view showing another angle of the backlight module according to a preferred embodiment of the present invention.

4 is a partial bottom view of a backlight module in accordance with a preferred embodiment of the present invention.

FIG. 5 is a partial schematic view of a support column according to a preferred embodiment of the present invention.

FIG. 6 is a top view of a center symmetrical figure according to a preferred embodiment of the present invention.

FIG. 7 is a top view of a center symmetrical figure according to another preferred embodiment of the present invention.

FIG. 8 is a top view of a center symmetrical figure according to still another preferred embodiment of the present invention.

FIG. 9 is a schematic diagram showing the optical principle of a light-emitting unit and a support column according to a preferred embodiment of the present invention.

200. . . Backlight module

210. . . Light unit

220. . . Support column

221. . . top

222. . . bottom

2221. . . The hook

2222. . . Baffle

2223. . . Chassis

223. . . Side

230. . . Backplane

231. . . Positioning hole

240. . . Optical diaphragm

Claims (10)

A backlight module comprising:
a backboard
An optical film located above the back plate;
a light-emitting unit disposed on the back plate between the back plate and the optical film, the light-emitting unit forming a central symmetrical pattern; and a support column at a center of the central symmetrical figure, wherein the support column include:
a top located below the optical film;
a bottom, connecting the backboard;
A side portion is sandwiched between the top portion and the bottom portion, the side portion is surrounded by a side surface, wherein the light emitting unit is located on a vertical line of the bottom side of the side surface. The backlight module of claim 1, wherein the support column comprises a transparent material. The backlight module of claim 2, wherein the transparent material has a light transmittance equal to or greater than 50%. The backlight module of claim 2, wherein the transparent material is selected from the group consisting of polymethyl methacrylate, polycarbonate, nylon, polypropylene, polystyrene, and glass, or a combination thereof. . The backlight module of claim 1, wherein the top of the support column has a spherical cap, and the spherical cap has a smooth transition connection with the side. The backlight module of claim 1, wherein the bottom of the support column has a hook, the back plate is provided with a positioning hole, and the hook passes through the positioning hole and is locked in the positioning. The circumference of the hole. The backlight module of claim 6, wherein the bottom of the support column further has a baffle, and a periphery of the positioning hole further defines a baffle corresponding to the baffle, the baffle and the baffle The retaining holes are mated to each other. The backlight module of claim 7, wherein a top end of the baffle is connected to the side of the support post, and a bottom end of the baffle is connected to the hook. The backlight module of claim 7, wherein the baffle and the hook are crossed on the projection surface. The backlight module of claim 6, wherein the bottom of the support column further has a chassis, the hook is located below the chassis, and the chassis is above the backplane.