CN102798033B - Backlight module - Google Patents

Abstract

The invention relates to a backlight module, which includes a backplane, a light guide plate, at least one light source, an optical film and a plastic frame. The light guide plate is disposed on the back plate and has at least one light incident surface and one light output surface. The at least one light source faces the at least one light incident surface. The optical film is disposed on the light exit surface of the light guide plate. The plastic frame is arranged around the light guide plate. The plastic frame has a rib and a plurality of pillars. The rib is located at a relative position above the periphery of the light-emitting surface. The pillars are connected to the rib and are located on the rib. and the back plate, so that the end surfaces of the pillar portions are lower than the light-emitting surface. This can reduce processing time and parts costs, prevent the light guide plate from cracking and melting after being heated, and fix the optical film and the light guide plate.

Description

Backlight module

technical field

The invention relates to a backlight module, in particular to a backlight module which has a plastic frame and the end faces of a plurality of pillars of the plastic frame are lower than the light-emitting surface.

Background technique

Fig. 1A shows the top view of the existing backlight module disclosed by the Taiwan No. I287664 patent; Fig. 1B shows the cross-sectional view of the existing backlight module disclosed by the Taiwan No. I287664 patent; Fig. 1C shows the disclosed by the Taiwan No. I287664 patent The top view of the optical film of the existing backlight module. With reference to FIGS. 1A to 1C , the conventional backlight module 1 includes a backplane 11 , a light guide plate 12 , a light source 13 , a plastic frame 14 and a multilayer optical film 15 . The light guide plate 12 is disposed on the back plate 11 and has a light emitting surface 121 . The light source 13 is close to a side wall of the light guide plate 12 .

The plastic frame 14 is disposed around the back plate 11 , and the plastic frame 14 has a front frame 141 , a plurality of protruding structures 142 and a front frame side 143 . The front frame 141 is disposed around the light emitting surface 121 , and the front frame side 143 surrounds the back plate 11 and the light guide plate 12 . The protruding structures 142 protrude toward the front frame 141 and are disposed around the periphery of the front frame 141 , and the protruding structures 142 are located between the light emitting surface 121 of the light guide plate 12 and the front frame 141 . There is a gap 16 between the light emitting surface 121 and the front frame 141, and the gap 16 is used to arrange the optical films 15, and the optical films 15 are arranged on the light emitting surface 121 of the light guide plate 12 for use To improve the brightness and uniformity of the existing backlight module 1 . Wherein, the edges of the optical films 15 have a plurality of holes 151 corresponding to the protruding structures 142 . The peripheral edges of the optical films 15 are located in the gap 16 but are not fixed by the protruding structures 142 to provide space for the optical films 15 to deform.

In the conventional backlight module 1 , there is an additional process of forming the holes 151 at the edges of the optical films 15 , which increases the processing time and cost. Moreover, the light guide plate 12 in the existing backlight module 1 does not have a good fixing effect, and when the stamping deformation of the back plate 11 is too large, it cannot maintain the distance between the light source 13 and the light guide plate 12. The light board 12 has the problem of melting after being heated.

In addition, in other existing backlight modules with positioning posts on the backplane, the light guide plate needs to be cut into grooves, which increases the cutting time and component cost. Moreover, the light guide plate of the existing backlight module may break when subjected to mechanical impact. In addition, when the stamping deformation of the backplane is too large, the positioning pins will cause the gap between the light source and the light guide plate to be too small. This kind of conventional backlight module also has the problem of melting the light guide plate after being heated.

Therefore, it is necessary to provide an innovative and progressive backlight module to solve the above problems.

Contents of the invention

The technical problems to be solved by the present invention are: the processing time and cost of the existing backlight module are high; or the light guide plate does not have a good fixing effect, and may melt after being heated, or may be broken when subjected to mechanical impact.

The invention provides a backlight module, which includes a back plate, a light guide plate, at least one light source, an optical film and a plastic frame. The light guide plate is arranged on the back plate and has at least one light incident surface and one light exit surface. The at least one light source faces the at least one light incident surface. The optical film is arranged on the light emitting surface of the light guide plate. The plastic frame is arranged on the periphery of the light guide plate, the plastic frame has a rib and a plurality of pillars, the ribs are located at opposite positions above the periphery of the light-emitting surface, the pillars are connected to the ribs, and are located on the ribs and the back plate, so that the end surfaces of the pillars are lower than the light emitting surface.

In other words, the present invention provides a backlight module, comprising:

a backplane;

A light guide plate, arranged on the back plate, has at least one light incident surface and one light exit surface;

At least one light source facing the at least one light incident surface;

an optical film disposed on the light-emitting surface of the light guide plate; and

A plastic frame is arranged on the periphery of the light guide plate, the plastic frame has a rib and a plurality of pillars, the ribs are located at opposite positions above the periphery of the light-emitting surface, the pillars are connected to the ribs, and are located on the ribs part and the back plate, so that the end surfaces of the column parts are lower than the light emitting surface.

In the above backlight module, preferably, the at least one light source is disposed between a side wall of the back plate and the light guide plate or between a bottom surface of the back plate and the light guide plate.

Or preferably, the rib contacts the optical film or the light-emitting surface.

Or preferably, the at least one light source is a lamp tube or a light emitting diode.

Or preferably, the optical film is selected from the group consisting of a diffusion film, a polarizing film, a wide viewing angle film, a retardation film and a brightness enhancement film.

Or preferably, the light guide plate has a plurality of first openings, the first openings correspond to the column parts, and the optical film has a plurality of second openings, the second openings correspond to the first Opening holes, the columns pass through the second openings and are disposed in the first openings. Further preferably, the first openings are through holes, and the back plate has a plurality of third openings corresponding to the first openings, and the columns pass through the second openings of the optical film and the first openings are fixed in the third openings; or the periphery of the optical film has a plurality of outward flange portions, and the second openings are located at the flange portions. Further preferably, the third openings are punched holes, and the periphery of each punching hole has an extended flange, and the pillars are fixed after passing through the second openings and the first openings of the optical film in such extension flanges.

In the above backlight module, preferably, the rib is an integrally formed ring plate.

Or preferably, the rib is a ring plate formed by a plurality of plates.

Or preferably, it also includes a plurality of rubber parts, which are arranged between the corresponding column parts and the corner side wall of the light guide plate, and are fixed on the back plate, and the back plate has a plurality of third openings corresponding to the corresponding column parts. holes, the pillars are fixed in the third openings, and the pillars contact the rubber parts. Further preferably, the outer peripheral surfaces of the pillars contact the rubber parts; or each rubber part has an L-shaped structure, and the L-shaped surface of the rubber part contacts the corner side wall of the light guide plate.

Or preferably, it also includes a plurality of rubber parts, arranged between the columns and the four side walls of the light guide plate, and fixed to the back plate, the back plate has a plurality of third openings corresponding to the columns. holes, the pillars are fixed in the third openings, and the pillars contact the rubber parts. Further preferably, the outer peripheral surfaces of the pillars are in contact with the rubber parts. Therefore, the present invention has the following advantages (or beneficial technical effects). The light guide plate does not need to cut grooves, thereby reducing the man-hours of cutting and polishing; the back plate may not have positioning columns, so as to reduce the man-hours of processing and the cost of parts; it can reduce the problem that the light guide plate is broken by mechanical impact; keep the at least one The distance between the light source and the light guide plate is to improve the problem that when the stamping deformation of the back plate is too large in the prior art, the positioning columns will cause the gap between the LED and the light guide plate to be too small, and the light guide plate will melt after being heated; these columns pass through The opening of the optical film and the end faces of the columns of the plastic frame are lower than the light-emitting surface, which can effectively suppress the optical film and the light guide plate and prevent the plastic frame from coming out when impacted by external force.

Description of drawings

Figure 1A shows a top view of a conventional backlight module;

Figure 1B shows a cross-sectional view of an existing backlight module;

FIG. 1C shows a top view of an optical film of a conventional backlight module;

FIG. 2A shows a three-dimensional exploded view of the first embodiment of the backlight module of the present invention;

FIG. 2B shows a combined rear top view of the first embodiment of the backlight module of the present invention;

FIG. 2C shows a combined cross-sectional view of the first embodiment of the backlight module of the present invention;

Fig. 3 has shown the schematic diagram of the plastic frame of another example of the backlight module of the first embodiment of the present invention;

FIG. 4 shows a partial cross-sectional view of another example of the backlight module of the first embodiment of the present invention;

Fig. 5 shows the top view of the second embodiment of the backlight module of the present invention;

6 shows a top view of the backplane of the backlight module of the second embodiment of the present invention;

FIG. 7 shows a partially enlarged view of the second embodiment of the backlight module of the present invention;

Fig. 8 has shown the usage state diagram of the backlight module of the second embodiment of the present invention;

Fig. 9 shows a partial perspective exploded view of the second embodiment of the backlight module of the present invention;

Fig. 10 shows the top view of the third embodiment of the backlight module of the present invention; and

FIG. 11 shows a top view of the backplane of the backlight module according to the third embodiment of the present invention.

[Description of main component symbols]

1 existing backlight module

2 The backlight module of the first embodiment of the present invention

3 The backlight module of the second embodiment of the present invention

4 The backlight module of the third embodiment of the present invention

11 Backplane

12 light guide plate

13 light source

14 rubber frame

15 optical film

16 gaps

21 Backplane

22 light guide plate

23 light sources

24 optical films

25 rubber frame

31 rubber pieces

41 rubber parts

51 backplane

121 light emitting surface

141 front frame

142 outstanding structures

143 front frame side

151 holes

211 bottom plate

212 side wall

213 third opening

214 extension flange

215 fourth opening

221 incident surface

222 light emitting surface

223 first opening

241 flange part

242 second opening

251 ribs

252 columns

311 rubber feet

411 Foot of rubber part

511 third opening

512 fourth opening

The end face of the 2521 column.

Detailed ways

Fig. 2A has shown the three-dimensional exploded view of the first embodiment of the backlight module of the present invention; Fig. 2B has shown the combination rear top view of the first embodiment of the backlight module of the present invention; Fig. 2C has shown the first embodiment of the backlight module of the present invention Sectional view after assembly. With reference to FIGS. 2A to 2C , the backlight module 2 includes a back plate 21 , a light guide plate 22 , at least one light source 23 , an optical film 24 and a plastic frame 25 .

In this embodiment, the backboard 21 includes a bottom board 211 and four sidewalls 212 , and the sidewalls 212 are substantially vertically connected to the bottom board 211 so that the backboard 21 forms an accommodating space. The light guide plate 22 is disposed on the bottom plate 211 of the back plate 21 for guiding the light from the at least one light source 23 to the light emitting surface 222 uniformly. The light guide plate 22 has at least one light incident surface 221 (the front side surface of the light guide plate 22, refer to FIG. 2A), a light output surface 222 (the upper surface of the light guide plate 22, refer to FIG. 2A) and a plurality of first openings 223 , wherein each first opening 223 does not penetrate through the light guide plate 22 . The light guide plate 22 is made of polymethyl methacrylate (PMMA).

The at least one light source 23 faces the at least one light incident surface 221 . The at least one light source 23 can be a light emitting diode or a lamp (for example: cold cathode fluorescent lamp (Cold Cathode Fluorescent Lamp, CCFL)). The at least one light source 23 is disposed between a sidewall of the backplane 21 and the light guide plate 22 or between a bottom surface of the backplane 21 and the light guide plate 22 . In this embodiment, the at least one light source 23 is disposed between the side wall 212 of the back plate 21 and a side wall (light incident surface 221 ) of the light guide plate 22 . Understandably, the at least one light source 23 can also be disposed between the bottom plate 211 of the back plate 21 and the light guide plate 22 . That is, the backlight module 2 of the present invention can be an edge-lit backlight module or a direct-light backlight module.

In this embodiment, the optical film 24 is disposed on the light emitting surface 222 of the light guide plate 22, the periphery of the optical film 24 has a plurality of outward flange portions 241, and the optical film 24 has a plurality of second openings. Hole 242. The second openings 242 are formed on the flange portions 241 of the optical film 24 . The second openings 242 correspond to the first openings 223 of the light guide plate 22 . The optical film 24 may be selected from a group consisting of a diffusion film, a polarizing film, a wide viewing angle film, a retardation film and a brightness enhancement film. In this embodiment, the optical film 24 has a three-layer film structure (refer to FIG. 2C ).

The plastic frame 25 is disposed around the light guide plate 22 . The plastic frame 25 has a rib 251 and a plurality of posts 252 . The rib 251 is located at a relative position above the periphery of the light-emitting surface 222 , and contacts the optical film 24 or the light-emitting surface 222 to compress the optical film 24 and the light guide plate 22 .

The pillars 252 are connected to the rib 251 and are located between the rib 251 and the back plate 21 , so that the end surfaces 2521 of the pillars 252 are lower than the light-emitting surface 222 . In this embodiment, the rib 251 is an integrally formed ring plate. It is understandable that the rib 251 may also be a ring plate (as shown in FIG. 3 ) composed of multiple plates.

In this embodiment, the pillars 252 pass through the second openings 242 of the optical film 24 and are disposed in the first openings 223 of the light guide plate 22, so that the ribs 251 contact the optical film 24. film 24 , and the ribs 251 contact the side wall 212 of the back plate 21 to form a frame for fixing and protecting the optical film 24 and the light guide plate 22 .

Referring to FIG. 4, it should be noted that the first openings 223 of the light guide plate 22 can also be through holes passing through the light guide plate 22, and the back plate 21 has a plurality of holes corresponding to the first openings 223. The third openings 213 are such that the post portions 252 are fixed in the third openings 213 after passing through the second openings 242 and the first openings 223 of the optical film 24 . In this embodiment, the third openings 213 are punched holes, and the periphery of each punching hole has an extending flange 214, and the column parts 252 pass through the second openings 242 and the second openings 242 of the optical film 24. The first openings 223 are then fixed in the extending flanges 214 . In this way, the column parts 252 pass through the second openings 242 of the optical film 24 and the first openings 223 of the light guide plate 22 and are fixed in the extending flanges 214, so that the number of openings 214 can be increased. The fixing effect of the column part 252 can prevent the plastic frame 25 from falling out when subjected to external forces such as mechanical impact.

Fig. 5 shows the top view of the second embodiment of the backlight module of the present invention; Fig. 6 shows the top view of the backplane of the backlight module of the second embodiment of the present invention; Fig. 7 shows the part of the second embodiment of the backlight module of the present invention Enlarged view; FIG. 8 shows the use state diagram of the backlight module of the second embodiment of the present invention; FIG. 9 shows a partial three-dimensional exploded view of the second embodiment of the backlight module of the present invention. With reference to FIGS. 5 to 9 , the backlight module 3 of this embodiment is substantially the same as the backlight module 2 ( FIG. 4 ) of the first embodiment, the difference is that the backlight module 3 of this embodiment also includes a plurality of rubber parts. ) 31, and in this embodiment, the column portions 252 are located at the four corners of the backlight module 3 and outside the light guide plate 22, that is, the column portions 252 are not as in the first embodiment pass through the light guide plate 22 . Preferably, the pillars 252 are directly fixed in the extension flanges 214 of the corresponding third openings 213 ( FIG. 4 ).

The rubber parts 31 are respectively disposed between the corresponding column portions 252 and the corner sidewalls of the light guide plate 22 . In this way, after the pillars 252 are fixed to the third openings 213 of the back plate 21 , the pillars 252 contact the rubber parts 31 . In this embodiment, the rubber parts 31 are fixed in the plurality of fourth openings 215 of the back plate 21 by using two feet 311, each rubber part 31 is an L-shaped structure, and the columns 252 The outer peripheral surface contacts the rubber parts 31 (the inner surface of the L-shaped rubber part 31 contacts the corner sidewall of the light guide plate 22 ). Other parts that are the same as those of the backlight module 2 ( FIG. 4 ) of the first embodiment are denoted by the same reference numerals, and will not be repeated here.

Referring to FIG. 8 again, the rubber parts 31 are elastically deformable materials, so the rubber parts 31 are arranged between the corresponding column parts 252 and the corner side walls of the light guide plate 22, not only can the light guide plate 22 be provided with a The function of cushioning can be expanded and contracted according to the hot and cold temperatures to provide space for deformation and ensure the close contact between the rubber parts 31 and the light guide plate 22 .

FIG. 10 shows a top view of the third embodiment of the backlight module of the present invention; FIG. 11 shows a top view of the backplane of the backlight module of the third embodiment of the present invention. With reference to FIG. 10 and FIG. 11 , the backlight module 4 of this embodiment is substantially the same as the backlight module 3 of the second embodiment ( FIG. 5 ), the difference lies in the structure of the rubber part 41 and its arrangement relationship with the back plate 51 . In this embodiment, the rubber member 41 is a straight structure, and the back plate 51 has a plurality of third openings 511 and a plurality of fourth openings 512 . The third openings 511 correspond to the column parts 252 . The third openings 511 and the fourth openings 512 are close to four edges of the back plate 51 . The columns 252 are fixed in the third holes 511, and the rubber parts 41 are fixed in the fourth holes 512 by two feet 411, so that the rubber parts 41 are arranged on the columns. Between the portion 252 and the four side walls of the light guide plate 22 , and the column portions 252 contact the rubber parts 41 .

Thus, the present invention has the following advantages. The light guide plate 22 does not cut grooves, which reduces the cutting and polishing man-hours; the back plate 21 does not have positioning columns, which reduces the processing man-hours and parts costs; it can reduce the problem that the light guide plate 22 is broken by mechanical impact; The distance between the at least one light source 23 and the light guide plate 22 is to improve the problem in the prior art that when the stamping deformation of the back plate is too large, the positioning column will cause the gap between the LED and the light guide plate to be too small, and the light guide plate will melt after being heated; The column parts 252 pass through the second openings 242 of the optical film 24, and the end surfaces of the column parts 252 of the plastic frame 25 are lower than the light-emitting surface 222, which can effectively compress the optical film 24 and the light guide plate 22, and prevent the rubber frame 25 from coming out when being impacted by an external force or the like.

The above-mentioned embodiments are only for illustrating the principles and functions of the present invention, and are not intended to limit the present invention. Therefore, those skilled in the art can modify and change the above-mentioned embodiments without departing from the spirit of the present invention. The protection scope of the present invention should be defined as the scope of the claims.

Claims (15)

1. A backlight module, comprising: a backplane; A light guide plate, arranged on the back plate, has at least one light incident surface and one light exit surface; At least one light source facing the at least one light incident surface; an optical film disposed on the light-emitting surface of the light guide plate; and A plastic frame is arranged on the periphery of the light guide plate, the plastic frame has a rib and a plurality of pillars, the ribs are located at opposite positions above the periphery of the light-emitting surface, the pillars are connected to the ribs, and are located on the ribs part and the back plate, so that the end surfaces of the column parts are lower than the light emitting surface. 2. The backlight module as claimed in claim 1, wherein the at least one light source is disposed between a side wall of the back plate and the light guide plate or between a bottom surface of the back plate and the light guide plate. 3. The backlight module as claimed in claim 1, wherein the rib contacts the optical film or the light emitting surface. 4. The backlight module as claimed in claim 1, wherein the at least one light source is a lamp or a light emitting diode. 5. The backlight module as claimed in claim 1, wherein the optical film is selected from the group consisting of a diffusion film, a polarizing film, a wide viewing angle film, a retardation film and a brightness enhancement film. 6. The backlight module as claimed in claim 1, wherein the light guide plate has a plurality of first openings, the first openings correspond to the column portions, and the optical film has a plurality of second openings, the The second openings correspond to the first openings, and the columns pass through the second openings and are disposed in the first openings. 7. The backlight module according to claim 6, wherein the first openings are through holes, and the back plate has a plurality of third openings corresponding to the first openings, and the pillars pass through the The second openings and the first openings of the optical film are then fixed in the third openings. 8. The backlight module as claimed in claim 7, wherein the third openings are punched holes, each punching hole has an extending flange, and the pillars pass through the second openings of the optical film And the first holes are fixed in the extension flanges. 9. The backlight module as claimed in claim 6, wherein a periphery of the optical film has a plurality of outward flange portions, and the second openings are located on the flange portions. 10. The backlight module as claimed in claim 1, wherein the rib is an integrally formed ring plate. 11. The backlight module as claimed in claim 1, wherein the rib is a ring plate formed by a plurality of plates. 12. The backlight module as claimed in claim 1, further comprising a plurality of rubber parts arranged between the corresponding pillars and the corner side walls of the light guide plate, and fixed to the back plate, the back plate has a plurality of pairs of The third openings of the pillars are fixed, the pillars are fixed in the third openings, and the pillars contact the rubber parts. 13. The backlight module according to claim 1, further comprising a plurality of rubber parts, arranged between the pillars and the four side walls of the light guide plate, and fixed to the back plate, the back plate has a plurality of pairs of The third openings of the pillars are fixed, the pillars are fixed in the third openings, and the pillars contact the rubber parts. 14. The backlight module as claimed in claim 12 or 13, wherein outer peripheral surfaces of the pillars contact the rubber parts. 15. The backlight module as claimed in claim 12, wherein each rubber member is L-shaped, and the L-shaped surface of the rubber member contacts the corner sidewall of the light guide plate.