TWI345100B - Light guide plate and backlight module using the same - Google Patents

Description

1345100 Modified replacement page on November 16, 099. Description of the Invention: [Technical Field] [0001] The present invention relates to a light guide plate applied to a liquid crystal display device, and a side-mounted backlight module using the same. [Prior Art] [0002] Since the liquid crystal of the liquid crystal display panel itself does not have the light-emitting property, in order to achieve the display effect, it is necessary to provide a light source to the liquid crystal display panel.

A device, such as a backlight module, functions to supply a surface light source that is sufficiently bright and evenly distributed to the liquid crystal display panel.

[0003] The backlight module of the prior art is mainly composed of a light source, a light guide plate, a reflection plate, a diffusion sheet and a cymbal sheet. The light source may be disposed on one side or two opposite sides of the light guide plate and emit light to the light guide plate. The light guide plate is configured to guide the light transmission direction so that the light is uniformly emitted from the light exit surface of the light guide plate, and the reflector is disposed opposite to the bottom surface of the light guide plate to reflect the light emitted from the bottom surface of the light guide plate into the light guide plate to improve the light. Utilization rate. The light-emitting surface of the diffusion sheet and the gusset relative to the light guide plate are sequentially disposed to make the light distribution from the light guide plate more uniform, thereby improving the brightness and uniformity of the liquid crystal display panel. [0004] According to the shape of the light guide plate, it can be divided into a flat light guide plate and a wedge light guide plate. In addition, in order to increase the light extraction efficiency and uniformity of the light guide plate, a V-shaped groove or a mesh point is usually disposed on one surface of the light guide plate, and the distance and size of the V-shaped groove or the mesh point distributed on the light guide plate may be different. When light is transmitted to a V-groove or dot, the light will be reflected and scattered, and transmitted in different directions, and finally emitted from the light-emitting surface of the light guide. The light guide plate can be uniformly illuminated by using various V-shaped grooves or dots of different sizes and sizes. 095134267 Form No. A0101 Page 4 of 19 0993410261-0 1345100 Revised Replacement Page November 16, 2010 [0005] As shown in FIG. 1, a backlight module 10 of the prior art is shown. The backlight module 1A includes a light guide plate 11, a light source 12, a reflection plate 15, and a diffusion sheet 16. The light guide plate 11 includes a light incident surface 112, a light exit surface 114 connected to the light incident surface 112, and a bottom surface 116 opposite to the light exit surface 114. The light source 12 is disposed adjacent to the light incident surface 112. The reflector 15 is disposed below the bottom surface 116. The diffusion sheet 16 is disposed above the light exit surface 114. In order to effectively utilize the light emitted by the light source 12, the backlight module 10 further includes a reflector cover 17 surrounding the light source 12. In order to destroy the total reflection condition of the light transmitted through the inside of the light guide plate 11, the bottom surface of the light guide plate 11 is further provided with a plurality of circular dots 118 arranged in a matrix.

As shown in FIG. 2, it is a schematic diagram of the distribution of the dots 118 on the bottom surface 116 of the light guide plate 11. The plurality of dots 118 are arranged in a plurality of columns in a direction parallel to the light incident surface 112 of the light guide plate 11, and the dots 118 are the same in each column. The plurality of dots 118 are arranged in a plurality of rows in a direction perpendicular to the axial direction of the light incident surface 112 of the light guide plate 11, and the sizes of the dots 118 in each row are different, wherein the diameter of the dots 118 near the light incident surface 112 is the smallest, as As the distance from the light source 2 increases, the dot 118 also gradually becomes larger. [0007] As shown in FIG. 3, the dot distribution of the light guide plate 11 is designed to be equidistant (pi tch), that is, the center line of the complex dot 118 of the same column and the center line of the complex dot 118 of the adjacent column X. The vertical distance γ is equal. Since the mesh point 118 of the pitch close to the light incident surface 112 is small in size, the gap between adjacent columns adjacent to the light incident surface 11 2 is large. The complex gap is applied to the display panel in a line-like arrangement. The area near the light-incident surface 112 may generate a plurality of bright lines, thereby directly reducing the display quality. [0008] 095134267 In view of this, it is provided that the light-emitting surface of the light guide plate can be reduced to be close to the light-incident surface. Form No. A0101 Page 5 / Total 19 Page 0993410261-0 1345100 November 16, 2010 Correction Replacement page appears bright line to improve Optically uniform light guides and backlight modules are necessary. SUMMARY OF THE INVENTION [0009] Hereinafter, a light guide plate capable of reducing a bright line appearing on a light incident surface of a light guide plate near a light incident surface, and a backlight module using the light guide plate will be described in several embodiments.

[0010] A light guide plate, comprising: a light incident surface; a light emitting surface connected to the light incident surface; a bottom surface opposite to the light emitting surface, the bottom surface is formed with a plurality of dots, the plurality of dots are distributed in a column shape, each One column is parallel to the axial direction of the incident surface, and the distance between the geometric centers of adjacent dots in each column is equal, and the farther away from the incident surface, the larger the dot size; and the farther away from the light-incident surface, each column The greater the vertical distance between the line connecting the geometric center of the dot and the geometric center of the adjacent column, the greater the dot density.

[0011] A backlight module includes at least one light source and a light guide plate, the light guide plate includes a light incident surface adjacent to the light source; a light emitting surface connected to the light incident surface; and a bottom surface opposite to the light emitting surface The bottom surface is formed with a plurality of dots, the plurality of dots are distributed in a column shape, each column is parallel to the axial direction of the light incident surface, and the distance between geometric centers of adjacent mesh points in each column is equal, and the farther from the light incident surface The larger the size of the dot, and the farther away from the light-incident surface, the greater the vertical distance between the line connecting the geometric center of each column and the geometric center of the adjacent column, and the greater the dot density. [0012] Compared with the prior art, the light guide plate of the embodiment adopts a non-equal pitch design: the same column dots close to the light incident surface are small in size, and the gap between the columns and the columns can be controlled appropriately. A smaller range, so as to avoid the occurrence of complex bright lines near the entrance surface to improve the optical efficiency of the backlight module. 095134267 Form No. A0101 Page 6 of 19 0993410261-0 1345100 Uniformity. </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> [0013] The backlight module and its light guide plate of the present invention will be further described in detail below with reference to the accompanying drawings and the embodiments. Referring to FIG. 4, a preferred embodiment 1 of the backlight module 2 of the present invention is shown. The backlight module 20 includes a light guide plate 21 and a light source 22. The light guide plate 21 includes a light incident surface 212; a light exit surface 214 connected to the light incident surface 21 2; and a bottom surface 216 opposite the light exit surface 214. The bottom surface 216 is formed with a plurality of dots 218. The light source 22 is disposed adjacent to the light incident surface 212 of the light guide plate 21. The light source 22 can be selected from a cold cathode fluorescent tube or a light emitting diode. The light guide plate a may be made of polycarbonate (PC), poly(meth) methacrylate (pmma), or other suitable transparent synthetic resin material. [0015] Referring to FIG. 5, the plurality of dots 21 8 are distributed in a column shape. Each column is parallel to the axial direction (X-axis direction) of the entrance surface 212. The geometric center-to-center spacing of adjacent dots 218 in each column is equal. The farther away from the light entrance surface 212, the larger the size of the mesh point 218. The vertical distance between the line Yn of the geometric center of the column 218 and the geometric center line Υη+1 of the adjacent column point 218 far from the light entrance surface 212 is Ypitch η, and the geometric center of the column 218 is connected. The vertical distance between Υη + ι and the geometric center line □ of the adjacent column dots 218 far from the entrance face 212 is γ 0 n+Z pitch_(n+l)

Ypitch_(n+1) is larger than Ypitch. In this embodiment, the distance Υ pi tch_l (not labeled) of the first column of mesh points 218 closest to the light incident surface 21 2 and its adjacent column dots 218 is the smallest. As described above, the farther away from the light incident surface 212, each column of dots The vertical distance between the line connecting the geometric center of 218 and the geometric center of its adjacent column points is larger, and the ratio of the area of the dot area per unit area is 095,134,267. Form No. A0101 Page 7/19 pages 0993410261-0 1345100 On November 16, 099, the density of the dot is larger. [0016] The dots 218 of each column in this embodiment are sized. It should be noted that for different light sources, the dots 218 in each column may have different unequal designs: as in each column, the middle dot 218 is the smallest, and the closer to the two ends, the size of the dot 218 gradually increases; or: The dot 218 in the middle of each column is the largest, and the closer to the two ends, the size of the dot 218 gradually becomes smaller [0017] The dot 218 in this embodiment is a square having an area of 1χ1〇-7 mm 2 to 1×10 mm 2 . . The plurality of dots 218 of the present invention can form ink dots by ink printing, or chemically engrave through a mask to produce dots having fine scattering matte. In this embodiment, the plurality of dots 21 8 are formed by ink printing to the bottom surface 21 6 ' of the light guide plate 21. The plurality of dots 218 include a general ink dot or an ink dot containing a scattering agent. [0018] Since the farther away from the light-incident surface 212, the dot density (the proportion of the dot area per unit area) is larger. The backlight module suffers from uniformity. Moreover, the dot distribution of the light guide plate 21 of the present invention is in the γ-axis direction, and the Pitch design is adopted: the same column dots 21 8 close to the light-incident surface 21 2 are small in size, but the gap between the columns and the columns can be The control is in a suitable smaller range to avoid generating a plurality of bright lines near the light incident surface 112 to improve the optical uniformity of the backlight module 20. [0019] Please refer to FIG. 6, a preferred embodiment 1 of the light guide plate of the present invention. The structure of the light guide plate 31 is substantially similar to that of the light guide plate 21, and the difference is that the light guide plate 31 has two opposite light incident surfaces 312, and a bottom surface 316 of the bottom surface 316. 095134267 Form No. A0101 Page 8 / 19 pages 0993410261- 0 1345100 3 1 8 The distribution changes accordingly. In this embodiment, on November 16, 099, a central axis X is defined between the light incident surfaces 312 of the light guide plate 31, and a gas Λιι, 161 between the female light incident surface 312 and the central axis XR The greater the vertical distance between the line connecting the geometric center of the 6' mother line and the geometric line in the adjacent column point, the greater the density of the dot. It can be understood that the two light-incident planes may receive beams of different intensities, and the distribution of the dots of the present invention may adopt an asymmetric design, that is, the center minus (4) may be selected as a plane-arbitrary-axis. [0021] Please refer to 7, preferred embodiment 2 of the material panel of the present invention. The structure of the light guide plate 41 is substantially similar to that of the light guide plate 31 of the first embodiment, except that the dot 418 thereof has a regular octagonal structure. Please refer to FIG. 8 for a preferred embodiment 3 of the light guide plate of the present invention. The structure of the light guide plate 51 is substantially similar to that of the light guide plate 31 of the preferred embodiment, except that the mesh point 518 has a heptagonal structure.

[0022] With reference to the above embodiments, it can be understood that the + π dot shape of the present invention can be variously modified, and its shape can include one of a dot and an arbitrary polygon. [_ can (4) solution, the above-mentioned light-mosquito complex (4) embodiments can all be equipped with the required light source assembly cost of the backlight module of the invention. [0025] As described above, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only the preferred embodiment of the present invention, and those skilled in the art of the present invention should be included in the following patents within the meaning of the invention. Brief Description of the Drawings Fig. 1 is a side view of a conventional backlight module β [0026] ® 2 is the bottom surface of the light guide plate shown in Fig. 1 dot 095134267 Form No. 第 _ _ 9 / 19 pages "Heart State 0993410261-0 1345100 099 November 16th, the shuttle replacement page [0027] FIG. 3 is an enlarged schematic view of a portion III of FIG. 4 is a side view of a preferred embodiment of a backlight module of the present invention. 5 is a schematic view showing the distribution of the mesh points on the bottom surface of the light guide plate of the backlight module shown in FIG. 4. 6 is a schematic diagram showing the distribution of the bottom mesh point of the preferred embodiment of the light guide plate of the present invention. [0031] FIG. 7 is a schematic diagram showing the distribution of the bottom mesh point of the preferred embodiment 2 of the light guide plate of the present invention.

8 is a schematic diagram showing the distribution of the bottom mesh points of the preferred embodiment 3 of the light guide plate of the present invention. [Main component symbol description] [0033] Backlight module: 20 [0034] Light guide plate: 21, 31, 41, 51 [0035] ] Light source: 22 [0036] Light into the surface: 212, 312

[0037] Light-emitting surface: 214 [0038] Bottom surface: 21 6, 31 6 [0039] Network: 21 8, 31 8, 41 8, 518 095134267 Form No. A0101 Page 10 of 19 0993410261-0

Claims (1)

1345100 VII. Patent application scope: A light guide plate comprising: a light-incident surface; a light-emitting surface connected to the light-incident surface; a bottom surface opposite to the light-emitting surface, the bottom surface is formed with a plurality of dots, the plurality of dots Listening, each column is parallel to the axial direction of the human light surface, the distance between the geometric centers of adjacent mesh points in each column is equal, and the farther away from the light entrance surface, the larger the mesh size, the improvement It is: the farther away from the illuminating surface, the greater the vertical distance between the line connecting the ugly geometry of each column and the geometric center of the phase _ dot, the greater the dot density. Such as the scope of patent application! In the light guide plate of the item, the shape of the plurality of dots is (four), and one of a dot and a polygon. The light guide plate of claim 1, wherein the plurality of dots are one of an ink dot and a dot having a fine scattering matte surface. The light guide plate of the invention of claim i, wherein the dot area ranges from lxl 〇 7 square millimeters to 1 χ 1 〇 4 square millimeters. If the guide wire described in the above paragraph is applied, the dots between the adjacent columns of the towel are staggered by a certain distance. The light guide plate of claim 1, wherein the dots of each of the columns are equal in size. The light guide plate of claim 1, wherein in each of the plurality of rows of dots, the dot in the middle is the smallest, and the closer to the both ends, the size of the dot gradually increases. • The light guide plate according to item 1 of the patent application, wherein the dot in the middle of each of the dots is the largest and the closer to the both ends, the size of the dots gradually becomes smaller. • The light guide plate according to item 1 of the patent application, wherein the light guide plate package 095134267 Form No. Α0101 Page 19/19 pages 0993410261-0 丄: 545100 I November 10, 2010 Replacement page I includes two relative Into the light surface, define an axis between the two entrance surfaces, each into the light surface /,. Between the axes of the sea, the farther away from the light-incident surface, the geometrical center of each column of dots and the vertical distance between the geometric center and the connecting line of the adjacent column points are larger, and the degree of the dot is greater. 10. The light guide plate of claim 9, wherein the axis is a central axis between the two entrance faces. a backlight module comprising at least a light source and a light guide plate, the light guide plate comprising: a light incident surface adjacent to the light source; a light exit surface connected to the light incident surface: a bottom surface opposite to the light exit surface, The bottom surface is formed with a plurality of dots, the plurality of dots are distributed in a column shape, each column is parallel to the axial direction of the human light surface, and the geometric center of the adjacent dots in the X column is equal to each other, and the light passing through the light entrance surface is Columns, the larger the size of the mesh points, the improvement is that the farther away from the geometric center of the mating point of the entrance pupil, the geometrical center of the mesh point and the geometric point of the mesh point make the vertical distance of the heart line larger, and the density of the dot is larger. 12. The backlight module of claim U, wherein the plurality of dots are in the shape of one of a dot and a polygon. 10 14 15 16 095134267 The backlight module of claim n, wherein the plurality of dots are ink dots and dots having fine scattering matte surfaces. The backlight module of claim U, wherein the dot area ranges from 1 x 107 square millimeters to 1 x 1 Q4 square millimeters. The backlight rib of claim 1, wherein the dots between the adjacent columns are staggered by a certain distance. The backlight module of claim 4, wherein the dots of each of the columns are equal in size. The backlight module of claim 11, wherein in each of the plurality of dots, the middle dot is the smallest ' and the closer to the both ends, the size of the dot is by the form number A0101. Page 12 of 19 09934 17 1345100 On November 16, 099, the replacement page is gradually increasing. The backlight module of claim 11, wherein in each of the plurality of dots, the middle dot is the largest, and the closer to the two ends, the size of the dot is gradually reduced. The backlight module of claim 11, wherein the light guide plate comprises two opposite light incident surfaces, and an axis is defined between the two light incident surfaces, and the distance between each light incident surface and the axis is farther away. The entrance surface of the light-incident surface, the greater the vertical distance between the line connecting the geometric center of each column and the geometric center line of its adjacent column points, the greater the dot density. 095134267 Form No. A0101 Page 13 of 19 0993410261-0