TWI402545B - Light guide plate and backlight module using the saem - Google Patents

Description

Light guide plate and backlight module using the same

The invention relates to a light guide plate and a backlight module using the light guide plate, in particular to a light guide plate suitable for a side-mounted backlight module and a side-mounted backlight module.

In recent years, flat display devices have developed rapidly and have been widely used in mobile communications and consumer electronics, such as digital cameras, video cameras, and mobile phones with camera functions (see Capturing images with digital still cameras, Micro, IEEE Volume: 18, issue: 6, Nov.-Dec. 1998 Page(s): 14-19). At the same time, the demand for electronic display devices for flat display devices (such as liquid crystal display devices) continues to increase. The backlight module is an important component in the display device, and the light emitted by the point source or the line source is scattered by the light guide plate to form a light source. Therefore, designing various backlight modules has become a research hot spot.

The backlight module generally includes a light source and a light guide plate, and the light source is disposed opposite to the light incident surface of the light guide plate. The light guide plate guides the direction of transmission of the light beam emitted from the light source, and converts the line source or the point source into a surface source. According to the position of the light source, the backlight module can be divided into two types: direct type and side type. The direct type backlight module refers to direct illumination of the light source directly under the light guide plate. The side-mounted backlight module generally places the light source on the side of the light guide plate, and the light is coupled into the light guide plate from the side surface to form a total reflection in the light guide plate and continuously propagate forward. By destroying the total reflection condition, the light exiting surface of the light guide plate is uniformly emitted. It can be seen that the structure of the light guide plate is opposite to the backlight module. The light output has an important impact.

Referring to FIG. 1 and FIG. 2 , the prior art provides a light guide plate 10 . The light guide plate 10 includes a light incident surface 11 , a light exit surface 12 intersecting the light incident surface 11 , and a bottom surface opposite to the light exit surface 12 . 13 and a side surface (not shown) connected to the light incident surface 11. The meshes 130 are disposed on the bottom surface 13 of the light guide plate 10, and the dots 130 are equally spaced on the bottom surface 13 of the light guide plate 10. When the light is transmitted to the dot 130, the light changes its reflection angle, that is, the total reflection phenomenon of the light transmission is broken, the light will be reflected and scattered, and transmitted to different directions, and finally emitted from the light exit surface 12 of the light guide plate 10. However, the light guide plate 10 of such a structure emits light unevenly, and the light-emitting surface 12 of the light guide plate 10 which is closer to the light source has a higher luminance, and the light-emitting surface 12 of the light guide plate 10 which is farther from the light source has a lower luminance, so the light guide plate 10 is low. Uniform emission of light cannot be achieved.

In order to improve the light uniformity of the light-emitting surface of the light guide plate, as shown in FIG. 3 and FIG. 4, the US Patent Application No. 20030137824 discloses a backlight module 14 comprising: a rectangular light guide plate 15, The lower surface, that is, the reflective surface, forms a plurality of intermittently distributed astigmatism grooves 16, an LED light source 17 disposed at a top corner of the light guide plate 15, a scattering prism sheet 18 disposed above the light guide plate 15, and a guide The reflection sheet 19 under the light plate 15 is distributed in a circular arc shape with the light source 17 as a center, and the adjacent arcs are equally spaced (as shown in FIG. 4). The plurality of astigmatism grooves 16 can improve the light uniformity of the backlight module 14 to some extent. However, the light guide plate 15 of such a structure does not match the shape of the light guide plate 15 due to the shape of the astigmatism groove 16 , so the backlight The light output of the module 14 is still not uniform enough, and the brightness of the light-emitting surface of the light guide plate 15 which is closer to the light source 17 is higher. The brightness of the light-emitting surface of the light guide plate 15 which is far from the light source is low, so that the light-emitting surface of the backlight module 14 is not uniform enough.

In view of the above, it is necessary to provide a light guide plate and a side-mounted backlight module that can improve the uniformity of light emission of the side-mounted backlight module.

a light guide plate, the light guide plate includes a light incident surface; a light exit surface, the light exit surface intersects the light incident surface; a bottom surface, the bottom surface is opposite to the light exit surface, the bottom surface is provided with a plurality of dots; and a side surface The side intersects the illuminating surface and the bottom surface. Adjacent to the bottom surface of the light-incident surface of the light guide plate, the dot is distributed in an arc shape, and the arc has the same center and faces the light-incident surface of the light guide plate, and is away from the bottom surface of the light-incident surface of the light guide plate. Or a column distribution, the row or column being parallel to the side of the light guide plate.

A backlight module includes a light source and a light guide plate. The light guide plate includes a light incident surface; a light exit surface, the light exit surface intersects the light incident surface; a bottom surface opposite to the light exit surface, the bottom surface is provided with a plurality of dots; and a side surface, the side surface and the light exiting The surface and the bottom surface intersect, and the light source is disposed relative to the light incident surface of the light guide plate. Adjacent to the bottom surface of the light-incident surface of the light guide plate, the dot is distributed in an arc shape, and the arc has the same center and faces the light-incident surface of the light guide plate, and is away from the bottom surface of the light-incident surface of the light guide plate. Or a column distribution, the row or column being parallel to the side of the light guide plate.

Compared with the prior art, the light guide plate and the backlight module using the light guide plate have the following advantages: because the bottom surface of the light guide plate adjacent to the light guide surface is distributed in an arc shape, the arc has the same center and faces the same The light incident surface of the light guide plate is away from the bottom surface of the light incident surface of the light guide plate, and the mesh point is A row or column distribution parallel to one side of the light guide plate, the distribution shape of the mesh point matching the shape of the light guide plate. Therefore, when the light is incident on the mesh point of the bottom surface of the light guide plate, the light is reflected and scattered through the mesh point, and then uniformly emitted on the light exit surface of the light guide plate, thereby improving the light uniformity of the light guide plate and the backlight module using the light guide plate.

The light guide plate provided by the present invention and the backlight module using the same will be further described in detail below with reference to the accompanying drawings.

Referring to FIG. 5 and FIG. 6 , a backlight module 20 is provided in the first embodiment of the present invention. The backlight module 20 includes a light source 21 and a light guide plate 22 . The light guide plate 22 may be a flat plate shape or a wedge shape. The flat plate light guide plate may be a rectangular parallelepiped or a rectangular parallelepiped, and the light exit surface of the wedge shaped light guide plate may be rectangular or square. The material of the light guide plate 22 may be polycarbonate, polymethyl methacrylate (PMMA) or acrylic synthetic resin. In this embodiment, the light source 21 is a point light source, and the light guide plate 22 is a rectangular parallelepiped flat light guide plate with a corner angle cut off. The material of the light guide plate 22 is PMMA, and the cut corner is an isosceles. triangle.

The light guide plate 22 includes a light incident surface 221, the light incident surface 221 is a side surface of the chamfered corner, a light exit surface 222 intersecting the light incident surface 221, a bottom surface 223 opposite to the light exit surface 222, and a light exiting surface. The side surface 222 and the bottom surface 223 intersect with each other. The light incident surface 221 and the side surface are located between the light emitting surface 222 and the bottom surface 223. The side surface is a first side surface 224, a second side surface 225, a third side surface 226, and a fourth side surface. 227. The light source 21 is disposed opposite to the light incident surface 221 of the light guide plate 22, and the light source 21 is a light emitting diode.

The bottom surface 223 of the light guide plate 22 is provided with a plurality of dots 2230, the dots 2230 may be a hemispherical shape, a pyramid, a prism, or a groove recessed inside the light guide plate 22, which protrudes to the outside of the light guide plate 22. In the embodiment, the shape of the dot 2230 is a hemispherical shape that protrudes toward the outside of the light guide plate 22. The bottom surface 223 of the light-incident surface 221 adjacent to the light guide plate is distributed in an arc shape, and each of the circular arcs has the same center, and the center of the circle is located at the center of illumination of the light source 21. The dots 2230 are evenly distributed on the same arc, and the distance between adjacent dots 2230 is 0.1 to 1 mm. The spacing between the arcs is equal, the distance between adjacent arcs is 0.5 to 2 mm, and the density of the dots 2230 distributed on the respective arcs increases as the distance from the light incident surface 221 of the light guide plate increases. The size of the dot 2230 does not change.

The mesh points 2230 are arranged in rows and columns, and the rows and columns are parallel to the second side surface 225 and the third side surface 226 of the light guide plate 22, respectively, away from the bottom surface 223 of the light-incident surface 221 of the light guide plate. Specifically, in a region formed by the diagonal line of the chamfer of the light guide plate and the first side surface 224 and the second side surface 225 of the light guide plate, each line of the dot 2230 is parallel to the second side surface 225 of the light guide plate 22, and the dot is 2230 is evenly distributed on each line, and the distance between adjacent dots is 0.1 to 1 mm. The spacing between the adjacent rows is equal, the spacing between adjacent rows is 0.5 to 2 mm, and the density of the distribution points 2230 distributed in each row increases with the distance from the light incident surface 221 of the light guide plate, and the size of the dot 2230 is not change. In a region formed by the diagonal line of the corner of the light guide plate and the third side surface 226 and the fourth side surface 227 of the light guide plate, the columns of the mesh points 2230 are parallel to the third side surface 226 of the light guide plate 22, and the mesh point 2230 is Each column is evenly distributed, and the spacing between adjacent dots is 0.1 to 1 mm. The spacing between the columns is equal, the spacing between adjacent columns is equal to the spacing between adjacent rows of another region, and is distributed across the density of each column of the Internet access point 2230. As the light entrance surface 221 is farther away from the light guide plate, the size of the dot 2230 does not change. On the intersecting rows and columns, the distance between adjacent dots is equal.

In order to improve energy utilization, the bottom surface 223 may be provided with an anti-reflection film (not shown), which is a metal or dielectric coating such as an aluminum film and a silver film. The bottom surface 223 includes a raised dot 2230 which can be formed by a process such as plating to make the bottom surface 223 have a higher reflectance. In addition, the first side surface 224, the second side surface 225, the third side surface 226, and the fourth side surface 227 should also have a high reflectivity, which can be achieved by a plating anti-reflection film (not shown).

It can be understood that the arcs formed by the mesh points 2230 of the bottom surface 223 of the light guide plate of the embodiment have the same center, but the position of the center of the circle is not particularly limited as long as it satisfies the arc formed by the plurality of dots 2230 toward the light guide plate 22. The light incident surface 221, that is, the concave surface of the circular arc faces the light incident surface 221 of the light guide plate 22.

The light emitted by the light source 21 enters the light guide plate 22 through the light incident surface 221 of the light guide plate 22, and a part of the light is incident on the mesh point 2230 of the bottom surface 223 of the light guide plate, and a part of the light is incident on the light exit surface 222 of the light guide plate and then reflected to the light guide surface 222. At the mesh point 2230 of the bottom surface 223 of the light guide plate, when the light is incident on the mesh point 2230, the light will change its reflection angle, that is, the total reflection phenomenon of the light transmission is broken, the light will be reflected and scattered, and transmitted to various directions, and finally The light exit surface 222 of the light guide plate 22 is emitted. Because the bottom surface 223 of the light incident surface 221 of the light guide plate is adjacent to the bottom surface 223 of the light guide surface 221, the dot 2230 is disposed in an arc shape away from the bottom surface 223 of the light incident surface 221 of the light guide plate, and the dot 2230 is distributed in rows and columns. Parallel to the second side 225 and the third side 226 of the light guide plate 22, the distribution shape of the dot 2230 matches the shape of the light guide plate 22. Therefore, light is incident on the bottom surface 223 of the light guide plate. At the dot 2230, the light is uniformly reflected by the light-emitting surface 222 of the light guide plate 22 after being reflected and scattered by the dot 2230, thereby improving the light uniformity of the light guide plate 22 and the backlight module 20 using the light guide plate 22.

Referring to FIG. 7 , a backlight module 30 according to a second embodiment of the present invention includes a light source 31 and a light guide plate 32 . The light source 31 is a point light source, and the light guide plate 32 is a rectangular parallelepiped flat light guide plate with a corner angle cut away. In the present embodiment, the light guide plate 32 is made of a polycarbonate material, and one of the cut corners is an isosceles triangle.

The light guide plate 32 includes a light incident surface 321 which is a side surface of the chamfered corner, a light exit surface (not shown) intersecting the light incident surface 321 , and a bottom surface 323 opposite to the light exit surface. The light incident surface 321 and the side surface are located between the light emitting surface and the bottom surface 323 on a side surface intersecting the light emitting surface and the bottom surface 323. The side surface is a first side surface 324, a second side surface 325, a third side surface 326, and a fourth side surface 327. The light source 31 is disposed relative to the light incident surface 321 of the light guide plate 32. The light source 31 is a light emitting diode.

The bottom surface 323 of the light guide plate 32 is provided with a plurality of dots 3230 protruding toward the outside of the light guide plate 32, and the dots 3230 are V-shaped microstructures. The dot 3230 is distributed in an arc shape on a bottom surface 323 adjacent to the light incident surface 321 of the light guide plate. The arcs have the same center, and the center of the circle is located on the right side of the light source 31. The dots 3230 are evenly distributed on the same arc. As the distance from the light entrance surface 321 of the light guide plate 32 is smaller, the distance between the arcs is smaller and the density of each arc point 3230 is larger. .

The grids 3230 are arranged in rows and columns, and the rows and columns are parallel to the second side 325 of the light guide plate 32 respectively. The third side 326. Specifically, in a region formed by the diagonal line of the chamfer of the light guide plate and the first side 324 and the second side 325 of the light guide plate, the rows of the dots 3230 are parallel to the second side 325 of the light guide plate 32, and the dots are The 3230 is evenly distributed on each line. As the light entrance surface 321 is away from the light guide plate 32, the spacing between adjacent rows is smaller and the density of the respective line access points 3230 is larger and larger. In the region formed by the diagonal line of the corner of the light guide plate and the third side 326 and the fourth side 327 of the light guide plate, the columns of the dots 3230 are parallel to the third side 326 of the light guide plate 32, and the dots 3230 are Each column is evenly distributed. As the light entrance surface 321 is away from the light guide plate 32, the spacing between adjacent columns becomes smaller and smaller, and the density of the respective column access points 3230 becomes larger and larger.

It can be understood that the distribution of the dots on the arc, each row and each column may be uneven, and the size of the dots may be arbitrarily adjusted by the uniformity of light emission.

Please refer to FIG. 8 , which is a backlight module 40 according to a third embodiment of the present invention. The backlight module 40 includes a light source 41 and a light guide plate 42 . The light guide plate 42 includes a light incident surface 421 and a bottom surface 423. The bottom surface 423 is provided with a plurality of dots 4230. The backlight module 40 of the embodiment is basically the same as the backlight module 30 of the second embodiment, and the difference is that the center of the arc of the dot 4230 is located on the left side of the light source 41, and the arc formed by the plurality of dots 4230 faces the arc. The light incident surface 421 of the light guide plate 42, that is, the concave surface of the circular arc faces the light incident surface 421 of the light guide plate 42, so that all light entering from the light incident surface 421 is reflected and scattered by the plurality of mesh dots 4230 of the bottom surface 423.

Referring to FIG. 9 and FIG. 10, a backlight module 50 according to a fourth embodiment of the present invention includes a light source 51 and a light guide plate 52. In the embodiment, the light source 51 is a point light source, and the light guide plate 52 is a rectangular parallelepiped light guide plate, and the material of the light guide plate 52 is PMMA.

The light guide plate 52 includes a light incident surface 521, a light exit surface 522 intersecting the light incident surface 521, a bottom surface 523 opposite to the light exit surface 522, and a side surface intersecting the light exit surface 522 and the bottom surface 523. The smooth surface 521 and the side surface are located between the light-emitting surface 522 and the bottom surface 523. The side surface is a first side surface 524, a second side surface 525, and a third side surface 526. The light source 51 is disposed on the light incident surface 521 of the light guide plate 52. The light source 51 is a light emitting diode.

The bottom surface 523 of the light guide plate 52 is provided with a plurality of dots 5230, which are hemispherical convex toward the outside of the light guide plate 52. The bottom surface 523 of the light-incident surface 521 adjacent to the light guide plate is distributed in an arc shape, and each of the circular arcs has the same center, and the center of the circle is located at the center of the light source 51. The dots 5230 are evenly distributed on the same arc, and the spacing between adjacent dots 5230 is 0.1 to 1 mm. The spacing between the arcs decreases gradually away from the light incident surface 521 of the light guide plate, the spacing between adjacent arcs is 0.5 to 2 mm, and the density of the dots 5230 distributed on the respective arcs varies with The light incident surface 521 is gradually increased away from the light guide plate, and the size of the mesh point 5230 does not change.

The grids 5230 are arranged in a row, and the rows are parallel to the second side 525 of the light guide plate 52. The dots 5230 are evenly distributed on each column, and the spacing between adjacent dots is evenly distributed on the bottom surface 523 of the light-incident surface 521 of the light guide plate. It is 0.1 to 1 mm. The spacing between adjacent columns gradually decreases with distance from the light-incident surface 521 of the light guide plate, the spacing between adjacent columns is 0.5 to 2 mm, and the density of the dots 5230 distributed on the respective columns is away from the light guide plate. The light incident surface 521 is gradually increased, and the size of the halftone dot 5230 is unchanged.

Please refer to FIG. 11 , which is a backlight module 60 according to a fifth embodiment of the present invention. The backlight module 60 includes a light source 61 and a light guide plate 62. In this embodiment, the light source 61 is a point light source, and the light guide plate is used. 62 is a square plate light guide plate, and the material of the light guide plate 62 is PMMA.

The light guide plate 62 includes a light incident surface 621, a light emitting surface (not shown) intersecting the light incident surface 621, a bottom surface 623 opposite to the light emitting surface, and a side intersecting the light emitting surface 622 and the bottom surface 623. The light incident surface 621 and the side surface are located between the light emitting surface and the bottom surface 623. The side surface is a first side surface 624, a second side surface 625, and a third side surface 626. The light source 61 is disposed on the light incident surface 621 of the light guide plate 62. The light source 61 is a light emitting diode.

The bottom surface 623 of the light guide plate 62 is provided with a plurality of dots 6230 which are hemispherical convex toward the outside of the light guide plate 62. The bottom surface 623 of the light-incident surface 621 adjacent to the light guide plate is distributed in an arc shape, and each of the circular arcs has the same center, and the center of the circle is located at the center of the light source 61. The dots 6230 are evenly distributed on the same arc, and the spacing between adjacent dots 6230 is 0.1 to 1 mm. The spacing between the arcs decreases gradually away from the light incident surface 621 of the light guide plate, the spacing between adjacent arcs is 0.5 to 2 mm, and the density of the dots 6230 distributed on each arc follows The light incident surface 621 away from the light guide plate gradually increases, and the size of the mesh point 6230 does not change.

The mesh points 6230 are arranged in rows or columns, specifically, adjacent to the bottom surface 623 of the first side surface 624 of the light guide plate. The dots 6230 are distributed in a row, and the row is parallel to the guide. The first side 624 of the light panel. The mesh points 6230 are arranged in a row adjacent to the bottom surface 623 of the third side 626 of the light guide plate, and the row is parallel to the third side 626 of the light guide plate. to Near the bottom surface 623 of the second side 625 of the light guide plate, the dots 6230 are arranged in a column, and the column is parallel to the second side 625 of the light guide plate. The dots 6230 are evenly distributed on each row or column, and the spacing between adjacent dots is 0.1 to 1 mm. The spacing between the rows or columns gradually decreases as the distance between the first side 624, the second side 625, and the third side 626 of the light guide plate 62 decreases, and the spacing between adjacent rows or columns is 0.5 to 2 mm. The density of the dots 6230 distributed over the respective rows or columns gradually increases, and the size of the dots 6230 does not change.

It can be understood that the spacing between the rows or columns can be equal. The distribution of the dots on the arc, each row and each column can also be uneven, and the size of the dots can be arbitrarily adjusted by the uniformity of light emission. of.

The light guide plate provided by the embodiment of the invention and the backlight module using the light guide plate have the following advantages: because the bottom surface of the light guide plate is provided with a mesh point, the mesh point is distributed in an arc shape adjacent to the bottom surface of the light incident surface of the light guide plate. Each of the arcs has the same center and faces the light incident surface of the light guide plate. The mesh points are arranged in a row or a column away from the bottom surface of the light incident surface of the light guide plate. The row or column is parallel to one side of the light guide plate. The distribution shape of the dots matches the shape of the light guide plate. Therefore, when the light is incident on the mesh point of the bottom surface of the light guide plate, the light is reflected and scattered through the mesh point, and then uniformly emitted on the light exit surface of the light guide plate, thereby improving the light uniformity of the light guide plate and the backlight module using the light guide plate.

In addition, a periodically arranged microstructure may be disposed on the light incident surface of the light guide plate, for example, a V-shaped microstructure arranged in a longitudinal period, a semi-cylindrical convex microstructure periodically distributed, or a convex microstructure having other periodic distributions, The microstructure also enhances the uniformity of the incident light from the source. On the light-emitting surface of the light guide plate A dot can also be provided to improve the light uniformity of the light guide plate and control the direction of the emitted light.

In summary, 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 a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

20, 30, 40, 50, 60‧‧‧ backlight modules

21, 31, 41, 51, 61‧‧‧ light source

22, 32, 42, 52, 62‧‧‧ light guides

221, 321, 421, 521, 621‧‧‧ into the glossy surface

223, 323, 423, 523, 623‧‧‧ bottom

224, 324, 524, 624‧‧‧ first side

225, 325, 525, 625‧‧‧ second side

226, 326, 526, 626‧‧‧ third side

227, 327‧‧‧ fourth side

2230, 3230, 4230, 5230, 6230‧‧‧ outlets

1 is a front elevational view of a prior art light guide plate.

2 is a bottom view of a prior art light guide plate.

Figure 3 is a front elevational view of a backlight module of the prior art of U.S. Patent No. 2,030,137,824.

4 is a schematic view showing the distribution of the microstructure of the reflecting surface of the light guide plate of FIG.

FIG. 5 is a schematic front view of a backlight module according to a first embodiment of the present invention.

FIG. 6 is a bottom view of a backlight module according to a first embodiment of the present invention.

FIG. 7 is a bottom view of a backlight module according to a second embodiment of the present invention.

FIG. 8 is a bottom view of a backlight module according to a third embodiment of the present invention.

FIG. 9 is a front elevational view of a backlight module according to a fourth embodiment of the present invention.

FIG. 10 is a bottom view of a backlight module according to a fourth embodiment of the present invention.

FIG. 11 is a bottom view of a backlight module according to a fifth embodiment of the present invention.

20‧‧‧Backlight module

21‧‧‧Light source

22‧‧‧Light guide plate

221‧‧‧Into the glossy surface

223‧‧‧ bottom

224‧‧‧ first side

225‧‧‧ second side

226‧‧‧ third side

227‧‧‧ fourth side

2230‧‧‧ outlets

Claims (18)

a light guide plate comprising: a light incident surface; a light emitting surface, the light emitting surface intersecting the light incident surface; a bottom surface, the bottom surface is opposite to the light emitting surface, the bottom surface is provided with a plurality of dots; and a side surface, the side surface intersecting the light-emitting surface and the bottom surface, wherein the bottom surface is adjacent to the light-incident surface, and the plurality of dots are distributed in an arc shape, the arcs having the same center and facing the a light incident surface of the light guide plate, wherein the bottom surface is away from the light incident surface, the plurality of dots are distributed in rows or columns, and the row or column is parallel to a side of the light guide plate. The light guide plate of claim 1, wherein the plurality of dots are evenly distributed on the same arc in a region of the bottom surface adjacent to the light incident surface. The light guide plate of claim 1, wherein the plurality of dots are evenly distributed on the same row or column in a region of the bottom surface away from the light incident surface. The light guide plate of claim 1, wherein the density of the dots distributed on the different arcs increases with the light incident surface away from the light guide plate in a region of the bottom surface adjacent to the light incident surface. The light guide plate according to the first aspect of the invention, wherein, in the region of the bottom surface away from the light incident surface, the density of the Internet dots distributed in different rows or columns increases with the light incident surface away from the light guide plate. The light guide plate of claim 1, wherein a distance between adjacent arcs is away from the light guide in a region of the bottom surface adjacent to the light incident surface The entrance surface of the board does not change or decrease. The light guide plate of claim 1, wherein a distance between adjacent rows or columns is constant or decreased with respect to a light incident surface away from the light guide plate in a region of the bottom surface away from the light incident surface. . The light guide plate of claim 1, wherein the light guide plate has an angle, and the light incident surface of the light guide plate is a side of the chamfer. A backlight module includes: a light source and a light guide plate, the light guide plate includes: a light incident surface; a light emitting surface, the light emitting surface intersects the light incident surface; and a bottom surface, the bottom surface is opposite to the light emitting surface The bottom surface is provided with a plurality of dots; and a side surface intersecting the light emitting surface and the bottom surface, wherein the light source is disposed relative to the light incident surface of the light guide plate, and the improvement is that the bottom surface is adjacent to the bottom surface In the region of the light-incident surface, the plurality of dots are distributed in an arc shape, and the arc has the same center and faces the light-incident surface of the light guide plate, and the plurality of dots are in a region away from the light-incident surface. Or a column distribution, the row or column being parallel to the side of the light guide plate. The backlight module of claim 9, wherein the arc of the plurality of dots is centered on the light source. The backlight module of claim 9, wherein the light source is a light emitting diode. The backlight module of claim 9, wherein the plurality of dots are evenly distributed on the same arc in a region of the bottom surface adjacent to the light incident surface. The backlight module of claim 9, wherein the bottom surface is The plurality of dots are evenly distributed on the same row or column away from the region of the light incident surface. The backlight module of claim 9, wherein in the region of the bottom surface adjacent to the light incident surface, the density of the dots distributed on different arcs increases with the light incident surface away from the light guide plate. The backlight module of claim 9, wherein in the region of the bottom surface away from the light incident surface, the density of the Internet dots distributed in different rows or columns increases with the light incident surface away from the light guide plate. The backlight module of claim 9, wherein a spacing between adjacent arcs is constant or decreases with respect to a light entrance surface away from the light guide plate in a region of the bottom surface adjacent to the light incident surface . The backlight module of claim 9, wherein, in a region of the bottom surface away from the light incident surface, a spacing between adjacent rows or columns is constant or subtracted from a light incident surface away from the light guide plate. small. The backlight module of claim 9, wherein the light guide plate has an angle, and the light incident surface of the light guide plate is a side of the chamfer.