CN100350311C

CN100350311C - Backlight module

Info

Publication number: CN100350311C
Application number: CNB2004100089204A
Authority: CN
Inventors: 张义辉
Original assignee: Toppoly Optoelectronics Corp
Current assignee: TPO Displays Corp
Priority date: 2004-03-15
Filing date: 2004-03-15
Publication date: 2007-11-21
Anticipated expiration: 2024-03-15
Also published as: CN1670585A

Abstract

The present invention relates to a back light module which comprises a plurality of point light sources which are arranged on a plate body, and a light guide plate which is provided with a light incident surface and a light emergent surface, wherein the light incident surface is provided with a protrusion part which is corresponding to the point light sources, and a long range part of the protrusion part is provided with a cambered groove. Thereby, light emitted by the point light sources enters the light incident surface, is evenly dispersed to the protrusion part by the cambered groove, and is emitted from light emergent surface.

Description

Direct type backlight module

Technical field

The present invention is particularly to a kind of direct type backlight module that is applied to LCD relevant for a kind of backlight module.

Background technology

Along with the lifting and the improvement of display fabrication techniques, (Liquid Crystal Display LCD) replaces traditional cathode-ray tube (CRT) (Cathode Ray Tube, CRT) display in recent years gradually to possess the LCD of characteristics such as little, the low radiation of volume.Generally speaking, known backlight liquid crystal display module (Back Lighting Module) adopts cold cathode fluorescent lamp mostly (Cold CathodeFluorescent Lamp is CCFL) as light emitting source.

As shown in Figure 1, being the three-dimensional exploded view of bottom-lighting type back light module, is the below of being located at liquid crystal panel 14, and this backlight module is made of reflecting plate 10, a plurality of cold cathode fluorescent lamp 11, light guide plate 12, diffuser plate 13, and the outboard profile after the combination as shown in Figure 2.Cold cathode fluorescent lamp 11 is as light emitting source, via below reflecting plate 10 or directly emit beam and penetrated to liquid crystal panel 14 by diffuser plate 13 via light guide plate 12.

Yet above-mentioned known backlight module is because light emitting source is a cold cathode fluorescent lamp, so light guide plate need be apart from these fluorescent tubes one suitable distances so that light source can be spread more uniformly when assembling, and the integral thickness of its backlight module is thicker after the therefore relative combination; And owing to utilize the negative electrode fluorescent tube when the light emitting source,,, therefore can use the higher diffuser plate of mist degree, so can make the brightness reduction for the striped that does not have light and shade that makes light-emitting area changes because fluorescent tube has a distance with the fluorescent tube interbody spacer.

Summary of the invention

In view of this, purpose of the present invention just is a kind of direct type backlight module is provided, and comprising: a plurality of pointolites are to be located on the substrate; An and light guide plate, have an incidence surface and an exiting surface, and this incidence surface has a protuberance corresponding to this pointolite respectively, and the long-range portion at this protuberance is provided with an arcuation groove, by this, above-mentioned light is luminous to enter above-mentioned incidence surface, via above-mentioned arcuation groove with the light uniformly dispersing to protuberance, penetrate from above-mentioned exiting surface.

According to the present invention, in light guide plate protuberance is set, and is provided with an arcuation groove in the long-range portion of each protuberance, to help light scatter in light guide plate, increase brightness, and reduce the thickness of backlight module; And owing to utilize light emitting diode to regard pointolite, light source is more even, therefore can use the lower diffuser plate of mist degree, and briliancy more can not disappear.

Description of drawings

Fig. 1 is the schematic perspective view of known backlight module;

Fig. 2 is the floor map of known backlight module;

Fig. 3 is a direct type backlight module sectional view of the present invention;

Fig. 4 is a direct type backlight module partial enlarged drawing of the present invention;

Fig. 5 a is the floor map of another its protuberance of preferred embodiment of the present invention;

Fig. 5 b is the schematic perspective view of another its protuberance of preferred embodiment of the present invention;

Fig. 6 is the planimetric map of LCD of the present invention.

Symbol description:

1～direct type backlight module; 14～liquid crystal panel;

10～reflecting plate; 11～cold cathode fluorescent lamp;

12～light guide plate; 13～diffuser plate;

2～backlight module; 20～light emitting diode;

22～light guide plate; 21～substrate;

220～incidence surface; 221～exiting surface;

24,24 '～protuberance; 240～close end;

241～long-range portion; 242～arcuation groove;

23～leaded light pattern; 3～liquid-crystal apparatus;

30～liquid crystal panel; 31～diffusion sheet.

Embodiment

For above and other objects of the present invention, feature and advantage can be become apparent, a preferred embodiment cited below particularly, and cooperate appended diagram, be described in detail below:

As shown in Figure 3, be the synoptic diagram of direct type backlight module 2 structures of the present invention.Wherein, backlight module 2 of the present invention includes a plurality of light emitting diodes 20 and a light guide plate 22.

Wherein, an above-mentioned majority light emitting diode 20 is evenly to be arranged on the substrate 21, to be used as pointolite with the array form.Light guide plate 22 can be polymethylmethacrylate (Polymethylmethacrylate, PMMA) or polycarbonate (Polycarbonate, material PC).Light guide plate 22 has an incidence surface 220 and an exiting surface 221, be provided with the protuberance 24 that a quantity is equal to above-mentioned light emitting diode 20 quantity in incidence surface 220, with corresponding each light emitting diode 20 of man-to-man mode, see also Fig. 4, this protuberance 24 is a frustum of a cone, to long-range 241 convergent, the cross-sectional area that makes close end 240 is greater than long-range 241 cross-sectional area by its close end 240.In addition, on the one side of long-range 241 respective leds 20, be provided with an arcuation groove 242, be beneficial to the even of light scatter.On exiting surface 221, then can be provided with for example leaded light pattern 23 of concave, convex shape lines, texture point or wavy lines, to help light to enter by the incidence surface 220 of light guide plate 22, through light guide plate 22 and leaded light pattern 23, penetrate from exiting surface 221, can obtain uniform face light.

Therefore, after backlight module 2 starts, the a plurality of light emitting diodes 20 that are arranged emit beam via the arcuation groove 242 of corresponding protuberance 24, this arcuation groove 242 is used as concavees lens, the light that receives is disperseed and diffuse on the incidence surface 220 that close end 240 is sent to light guide plate 22 then by the concavees lens principle by long-range 242 of protuberance 24, to exiting surface 221 ejaculations, the beginning can obtain uniform face light at last.

As shown in Figure 4, in the present embodiment, the shape of cross section of its close end 240 of protuberance is circular, its shape of cross section of long-range 241 then is the less circle of an area, so in the present invention, the shape of this protuberance is not limited to circle, also can be for example sexangle or other shape of Fig. 5 a and Fig. 5 b.

Shown in Fig. 5 a and Fig. 5 b, it is the protuberance 24 ' structure that shows another embodiment, the shape of cross section of this protuberance 24 ' its close end 240 ' is a sexangle, this long-range 241 ' then is circular, locate to be provided with an arcuation groove 242 ' at long-range 241 ', so protuberance 24 ' the layout shape on its whole light guide plate 22 can be dispersed to light source in the light guide plate fully uniformly promptly as cellular layout type.

Fig. 6 shows that one uses the liquid-crystal apparatus 3 of backlight module of the present invention, be to comprise: a liquid crystal panel 30, a diffusion sheet 31, light guide plate 22 and a plurality of light emitting diode 20, wherein light guide plate 22 and a plurality of light emitting diode 20 are all identical with last embodiment, do not repeat them here, it mainly is to be provided with diffusion sheet 31 above light guide plate 22, diffusion sheet 31 has the effect of diffusion light, can make brightness more even, and a liquid crystal panel 30 is set above diffusion sheet 31, to form a LCD 3.So, the light of each light emitting diode can at last, can evenly be launched from liquid crystal panel 30 via light guide plate 22 after diffusion sheet 31 penetrates.

By above-mentioned, the present invention can be provided with protuberance by the incidence surface place at diffuser plate and by using light emitting diode work as pointolite, need not interval one distance when making the diffuser plate assembling and between the light source, and make the thickness of backlight module thinner; And by its structural design with light emitting diode cooperation protuberance of the present invention, its light source is more even, therefore can use the lower diffusion sheet of mist degree, and briliancy more can not disappear.

Claims

1. direct type backlight module comprises:

A plurality of pointolites are to be located on the substrate; And

One light guide plate has an incidence surface and an exiting surface, and this incidence surface has a protuberance corresponding to this pointolite place respectively, and is provided with a groove corresponding to pointolite among this protuberance.

2. direct type backlight module according to claim 1, wherein this groove is the arcuation groove.

3. direct type backlight module according to claim 1, wherein this pointolite is a light emitting diode.

4. direct type backlight module according to claim 1, wherein this protuberance is a frustum of a cone structure, and this protuberance has long-range and one close end that closes on the incidence surface of this light guide plate away from the incidence surface of this light guide plate, wherein the xsect of the xsect of this close end and this long-range portion is rounded, and the cross-sectional area of this long-range portion is the cross-sectional area less than this close end.

5. direct type backlight module according to claim 1, wherein this protuberance is a frustum of a cone structure, and this protuberance has long-range and one close end that closes on the incidence surface of this light guide plate away from the incidence surface of this light guide plate, the xsect of this close end is to be hexagon, and the cross-sectional area of this long-range portion is less than the cross-sectional area of this close end.

6. direct type backlight module according to claim 1 more comprises:

One diffusion sheet is to be arranged on the exiting surface of this light guide plate.

7. direct type backlight module according to claim 1 wherein further is provided with the leaded light pattern on the exiting surface of this light guide plate.

8. direct type backlight module according to claim 7, wherein this leaded light pattern is concavo-convex lines.

9. direct type backlight module according to claim 1, wherein this light guide plate is polymethylmethacrylate or polycarbonate.

10. direct type backlight module according to claim 6 wherein more is provided with a liquid crystal panel above this diffusion sheet.