TWM447997U - Light guide plate with trumpet-shaped structure and backlight module using the same - Google Patents

Abstract

The present invention provides a light-guide plate with a trumpet-shaped structure including a main part, and a trumpet-shaped part. The main part has a first top surface and a bottom surface parallel to each other, and the trumpet-shaped part has a second top surface. The trumpet-shaped part is connected to a side of the main part, and a thickness of the trumpet-shaped part far away from the main part is larger than a thickness of the trumpet-shaped part close to the main part, so that the second top surface of the trumpet-shaped part is an inclined surface. The second top surface of the trumpet part has a plurality of micro structures.

Description

Light guide plate with horn shape structure and backlight module using same

The present invention relates to a light guide plate and a backlight module using the same, and more particularly to a light guide plate having a trumpet-shaped structure and a backlight module using the same.

With the rapid development of technology, liquid crystal displays are gradually moving toward the goal of thinning, so the thinning of the backlight module is also an important issue. In order to thin the backlight module, the type of the backlight module has evolved from a direct type to a side light type. The conventional edge-lit backlight module has a light-emitting diode disposed on one side of the light guide plate, so that the light of the light-emitting diode is incident from the side wall of the light guide plate, and then emitted from the upper surface of the light guide plate. Although a backlight module having the same thickness as the light-emitting diode has been developed to reduce the thickness of the entire backlight module, part of the light of the light-emitting diode cannot be incident on the light guide plate, resulting in Light utilization is declining. It can be seen that the thickness of the light guide plate is limited by the height of the light-emitting diode and cannot be reduced. In order to enable the light of the light-emitting diode to be incident on the light guide plate to achieve better light utilization efficiency, a light guide plate having a horn-shaped structure is developed. However, since the upper surface of the light guide plate of the horn-shaped structure is not a flat surface and has a part of the inclined surface, the light emitted from the inclined surface may be concentrated toward a part of the flat surface, thereby causing the user to see a part of the block. Other blocks are bright. In order to solve this problem, although the partial block is covered by the cover layer to avoid viewing the defect, the visible area of the display device is limited. In view of this, homogenizing the horn shape knot while avoiding the use of a cover layer to limit the visible area of the display device The surface light source generated by the light guide plate is the goal of the industry.

The main purpose of the present invention is to provide a light guide plate having a horn-shaped structure and a backlight module using the same, to homogenize the surface light source generated by the light guide plate of the horn shape structure.

For the above purposes, the present invention provides a light guide plate having a horn-shaped structure. The light guide plate includes a main body portion and a first horn shaped portion. The body portion has a first upper surface and a first lower surface parallel to each other, and the first flared portion has a second upper surface. The first horn-shaped portion is connected to one side of the main body portion, and the thickness of the first horn-shaped portion is larger as the distance from the main body portion is larger, so that the second upper surface of the first horn-shaped portion is an inclined surface. The second upper surface of the first horn shape portion has a plurality of first microstructures.

For the above purposes, the present invention provides a backlight module. The backlight module includes a light guide plate and at least one first light source. The light guide plate includes a main body portion and a first horn shaped portion. The body portion has a first upper surface and a first lower surface parallel to each other, and the first flared portion has a second upper surface. The first horn-shaped portion is connected to one side of the main body portion, and the thickness of the first horn-shaped portion is larger as the distance from the main body portion is larger, so that the second upper surface of the first horn-shaped portion is an inclined surface. The second upper surface of the first horn shape portion has a plurality of first microstructures. The first light source is disposed facing the first light incident surface.

By creating the first microstructure on the second upper surface, the light emitted from the second upper surface can be atomized, and the light emitted from the second upper surface is prevented from being excessively concentrated there. Thereby, the brightness of the light emitted from the second upper surface can be close to the brightness of the light emitted from the first upper surface of the main body portion to uniformize the surface light source emitted from the upper surface of the light guide plate.

Please refer to FIG. 1 and FIG. 2, which is a top plan view of a first preferred embodiment of the present invention, and FIG. 2 is a cross-sectional view along line A-A' of FIG. As shown in FIG. 1 and FIG. 2 , the backlight module 100 includes a light guide plate 102 , a plurality of first light sources 104 , and a plurality of second light sources 106 . The light guide plate 102 includes a main body portion 1022, a first horn shape portion 1024, and a second horn shape portion 1026. The main body portion 1022 has a first upper surface 1022a and a first lower surface 1022b parallel to each other. The first horn portion 1024 has a second upper surface 1024a, a second lower surface 1024b, and a first light incident surface 1024c. The second horn shaped portion 1026 has a third upper surface 1026a, a third lower surface, and a second light incident surface. The first horn shape portion 1024 is coupled to one side of the main body portion 1022 such that the first upper surface 1022a is coupled to the second upper surface 1024a, and the first lower surface 1022b is coupled to the second lower surface 1024b. The first light incident surface 1024c is located on the other side of the first horn shape portion 1024 with respect to the main body portion 1022 without being in contact with the main body portion 1022, and the first light source 104 is disposed facing the first light incident surface 1024c. Moreover, the first light source 104 has a first light emitting surface 104a, and the first light emitting surface 104a faces the first light incident surface 1024c. Thereby, the first light The light generated by the source 104 can be incident on the first horn shape portion 1024 via the first light incident surface 1024c, and further enter the main body portion 1022 and the second horn shape portion 1026 for the first upper surface 1022a and the second upper surface 1024a. And the third upper surface 1026a emits the surface light source.

In addition, the second horn-shaped portion 1026 is coupled to the other side of the main body portion 1022 with respect to the first light source 104, the third upper surface 1026a is coupled to the first upper surface 1022a, and the third lower surface 1026b is coupled to the first lower surface. 1022b is connected. The second light incident surface 1026c is located on the other side of the second horn shaped portion 1026 with respect to the main body portion 1022, and is not in contact with the main body portion 1022, and the second light source 104 is disposed facing the second light incident surface 1026c. Moreover, the second light source 106 has a second light exit surface 106a, and the second light exit surface 106a faces the second light incident surface 1026c. Thereby, the light generated by the second light source 106 can enter the second horn shape portion 1026 via the second light incident surface 1026c, and further enter the main body portion 1022 and the first horn shape portion 1024 for the first upper surface 1022a, The second upper surface 1024a and the third upper surface 1026a emit a surface light source. Further, the first flared portion 1024, the second flared portion 1026, and the main body portion 1022 are integrally formed. The number of the first light source 104 and the second light source 106 of the present invention is not limited to a plurality, but may be only one single.

It should be noted that the thickness of the first horn-shaped portion 1024 is larger as the distance from the main body portion 1022 is larger, so that the second upper surface 1024a of the first horn-shaped portion 1024 is an inclined surface inclined toward the main body portion 1022. . Therefore, the thickness of the main body portion 1022 of the embodiment may be smaller than the height of the first light source 104, and is not limited to be larger than the first light source 104. The height of the first light incident surface 1024c of the present embodiment is greater than the height of the first light source 104, so that the light emitted by the first light source 104 is efficiently incident on the first horn shape portion 1024. Moreover, the thickness of the main body portion 1022 can be reduced according to actual needs, even smaller than the height of the first light source 104, to effectively reduce the thickness of the backlight module 100, and can effectively utilize the light of the first light source 104 while maintaining a certain level. Light utilization. Similarly, the thickness of the second horn shaped portion 1026 also increases as the distance from the main body portion 1022 increases, so that the third upper surface 1026a of the second horn shaped portion 1026 is an inclined surface that is inclined toward the main body portion 1022. Therefore, the thickness of the main body portion 1022 of the embodiment may be smaller than the height of the second light source 106, and is not limited to be greater than the height of the second light source 106, and the height of the second light incident surface 1026c of the embodiment is greater than The height of the two light sources 106 causes the light emitted by the second light source 106 to efficiently enter the second flared portion 1026. Moreover, the thickness of the main body portion 1022 can be reduced according to actual needs, even smaller than the height of the second light source 106, to effectively reduce the thickness of the backlight module 100, and can effectively utilize the light of the second light source 106 while maintaining a certain level. Light utilization.

Please refer to FIG. 3, which is a side view of a portion of the backlight module of the first preferred embodiment of the present invention. As shown in FIG. 3, the second upper surface 1024a of the first horn shaped portion 1024 has a plurality of first microstructures 108. In the present embodiment, the first microstructures 108 include a plurality of first prismatic structures 108a that are parallel to each other, and the first prismatic structures 108a are sides that are perpendicular to the second upper surface 1024a and the body portion 1022. In other words, the height direction of each of the first prismatic structures 108a is disposed along a side direction in which the vertical second upper surface 1024a is connected to the main body portion 1022, and the first prismatic structure 108a is along the parallel second upper surface. Side of 1024a connected to main body 1022 The directions of the sides are arranged in order. The third upper surface 1026a of the second horn shaped portion 1026 has a plurality of second microstructures 110. In the present embodiment, the second microstructures 110 include a plurality of second prismatic structures 110a that are parallel to each other, and the second prismatic structures 110a also vertically extend the sides of the third upper surface 1026a that are connected to the body portion 1022. In other words, the height direction of each of the second prismatic structures 110a is disposed along a side direction in which the vertical third upper surface 1026a is connected to the main body portion 1022, and the second prismatic structure 110a is along the parallel third upper surface. The direction of the side of the 1026a connected to the main body portion 1022 is sequentially arranged.

It should be noted that, in this embodiment, the second upper surface 1024a and the third upper surface 1026a are emitted by the first upper structure 1024a being disposed on the second upper surface 1024a and the second upper surface 1026a being disposed on the third upper surface 1026a. The light can achieve the effect of atomization, and the light emitted from the second upper surface 1024a and the third upper surface 1026a is prevented from being excessively concentrated toward the two positions. Thereby, the brightness of the light emitted from the second upper surface 1024a and the third upper surface 1026a can be close to the brightness of the light emitted from the first upper surface 1022a of the main body portion 1022 to homogenize the light guide plate 102 from the first upper surface 1022a. The second upper surface 1024a and the surface light source emitted by the third upper surface 1026a.

The efficacy of this embodiment will be further explained below. Please refer to Figures 4 and 5, and refer to Figures 2 and 3 together. 4 is a schematic diagram showing the relationship between the position and the brightness of the backlight module having the horn shape but not having the first microstructure along the section line A-A' of FIG. 1 and the corresponding gray scale brightness, and FIG. Figure 5 is a diagram showing the relationship between the position and brightness of the backlight module of the first preferred embodiment of the present invention along the line A-A' of Figure 1 A schematic diagram of the corresponding grayscale brightness. As shown in FIG. 2 to FIG. 5 , the first curve C1 represents a relationship between the position of the first horn shape portion, the main body portion, and the second horn shape portion across the backlight module, and the first curve C1. The backlight module represented does not have a first microstructure and a second microstructure. The second curve C2 represents a relationship between the position of the first horn-shaped portion 1024, the main body portion 1022, and the second horn-shaped portion 1026 of the backlight module 100 of the present embodiment. Comparing the first curve C1 with the second curve C2, the difference between the brightness of the first curve C1 at a position of -80 mm and the brightness corresponding to 80 mm and the brightness at a position of 0 mm is greater than the position of the second curve C2 at the position - The difference between the brightness corresponding to 80 mm and 80 mm and the brightness corresponding to the position of 0 mm. Moreover, from the corresponding gray-scale luminance on the first curve C1 and the corresponding gray-scale luminance of the second curve C2, the surface light source generated by the backlight module without the first microstructure and the second microstructure is in the first The position of the horn shape portion and the second horn shape portion has a higher brightness, and the surface light source generated by the backlight module 100 of the embodiment has a position at the first horn shape portion 1024 and the second horn shape portion 1026. Low brightness. It can be seen that the light guide plate 102 of the present embodiment can be lowered from the second upper surface 1024a by providing the first microstructure 108 and the second microstructure 110 by the second upper surface 1024a and the third upper surface 1026a inclined toward the main body portion 1022. The difference between the brightness of the light emitted from the third upper surface 1026a and the brightness of the light emitted from the first upper surface 1022a, thereby uniformizing the light guide plate 102 from the first upper surface 1022a, the second upper surface 1024a, and the third upper surface 1026a The surface light source that is emitted.

The backlight module of the present invention is not limited to the above embodiment. Other embodiments or variations of the present disclosure will continue to be disclosed hereinafter, but to simplify the description and highlight the various embodiments or variations. In the following, the same components are denoted by the same reference numerals, and the repeated description will not be repeated.

Please refer to Figure 6 and Figure 7, and refer to Figure 4 together. 6 is a side view of a backlight module according to a second preferred embodiment of the present invention, and FIG. 7 is a cross-sectional line A-A' of the backlight module of the second preferred embodiment of the present invention. The relationship between the position of the direction and the brightness and the corresponding gray scale brightness. As shown in FIG. 6, the first prismatic structure 204 of the light guide plate 202 of the backlight module 200 of the present embodiment is parallel to one side of the second upper surface 1024a and the main body portion 1022. The side, and the second prismatic structure 206 is parallel to one side of the third upper surface 1026a and the main body portion 1022. As shown in FIGS. 4 and 7, the third curve C3 represents the position and brightness of the first horn-shaped portion 1024, the main body portion 1022, and the second horn-shaped portion 1026 of the backlight module 200 of the present embodiment. Relationship lines. Comparing the first curve C1 with the third curve C3, the difference between the brightness of the first curve C1 at a position of -80 mm and the brightness corresponding to 80 mm and the brightness at a position of 0 mm is greater than the position of the third curve C3 at the position - The difference between the brightness corresponding to 80 mm and 80 mm and the brightness corresponding to the position of 0 mm. Moreover, from the corresponding gray-scale brightness on the first curve C1 and the corresponding gray-scale brightness of the third curve C3, the surface light source generated by the backlight module without the first microstructure and the second microstructure is in the first The position of the horn shape portion and the second horn shape portion has a higher brightness, and the surface light source generated by the backlight module 200 of the embodiment has a position at the first horn shape portion 1024 and the second horn shape portion 1026. Low brightness. Therefore, the first prismatic structure 204 and the second prismatic structure 206 of the light guide plate 202 of the embodiment can also be lowered from the second upper surface 1024a and the third upper surface 1026a. The difference between the brightness of the emitted light and the brightness of the light emitted from the first upper surface 1022a, and uniformizes the surface light source emitted by the light guide plate 202 from the first upper surface 1022a, the second upper surface 1024a, and the third upper surface 1026a.

Please refer to Figure 8 and Figure 9, and refer to Figure 4 together. FIG. 8 is a side view of a backlight module according to a third preferred embodiment of the present invention, and FIG. 9 is a cross-sectional line A-A of the backlight module of the third preferred embodiment of the present invention. The relationship between the position of the 'direction' and the brightness and the corresponding gray-scale brightness. As shown in FIG. 8 , the first microstructure 304 of the light guide plate 302 of the backlight module 300 of the present embodiment includes a plurality of first circular arc columns 304a parallel to each other, and The second microstructure 306 includes a plurality of second arcuate columns 306a that are parallel to one another. The first circular arc columnar structure 304a vertically connects the second upper surface 1024a with one side of the main body portion 1022, and the second circular arc column structure 304a is perpendicular to the side of the third upper surface 1026a and the main body portion 1022. . As shown in FIGS. 4 and 9, the fourth curve C4 represents the position and brightness of the first horn-shaped portion 1024, the main body portion 1022, and the second horn-shaped portion 1026 of the backlight module 300 of the present embodiment. Relationship lines. Comparing the first curve C1 with the fourth curve C4, the difference between the brightness of the first curve C1 at a position of -80 mm and the brightness corresponding to 80 mm and the brightness at a position of 0 mm is greater than the position of the fourth curve C4 at the position - The difference between the brightness corresponding to 80 mm and 80 mm and the brightness corresponding to the position of 0 mm. Moreover, from the corresponding gray-scale luminance on the first curve C1 and the corresponding gray-scale luminance of the fourth curve C4, the surface light source generated by the backlight module without the first microstructure and the second microstructure is in the first The position of the horn shape portion and the second horn shape portion has a high brightness, and is produced by the backlight module 300 of the embodiment. The surface light source has a lower brightness at the position of the first flared portion 1024 and the second flared portion 1026. Therefore, the first arcuate columnar structure 304a and the second arcuate columnar structure 306a of the light guide plate 302 of the embodiment can also reduce the brightness of the light emitted from the second upper surface 1024a and the third upper surface 1026a. The difference in brightness of the light emitted from the first upper surface 1022a and uniformizes the surface light source emitted from the first upper surface 1022a, the second upper surface 1024a, and the third upper surface 1026a of the light guide plate 302.

Please refer to Figure 10 and Figure 11, and refer to Figure 4 together. 10 is a side view of a backlight module according to a fourth preferred embodiment of the present invention, and FIG. 11 is a cross-sectional line A-A of the backlight module of the fourth preferred embodiment of the present invention. The relationship between the position of the 'direction' and the brightness and the corresponding gray-scale brightness. As shown in FIG. 10, in comparison with the third embodiment, the first arc-shaped columnar structure of the light guide plate of the backlight module of the embodiment is parallel to the side of the second upper surface and the main body portion, and the first The two arcuate columnar structures are parallel to one side of the third upper surface and the main body portion. As shown in FIGS. 4 and 11, the fifth curve C5 represents the position and brightness of the first horn-shaped portion 1024, the main body portion 1022, and the second horn-shaped portion 1026 of the backlight module 400 of the present embodiment. Relationship lines. Comparing the first curve C1 with the fifth curve C4, the difference between the brightness of the first curve C1 at a position of -80 mm and the brightness corresponding to 80 mm and the brightness at a position of 0 mm is greater than the position of the fifth curve C5 at the position - The difference between the brightness corresponding to 80 mm and 80 mm and the brightness corresponding to the position of 0 mm. Moreover, from the corresponding gray-scale luminance on the first curve C1 and the corresponding gray-scale luminance of the fifth curve C5, the surface light source generated by the backlight module without the first microstructure and the second microstructure is in the first The position of the horn shape portion and the second horn shape portion has higher brightness, and the embodiment The surface light source generated by the backlight module 400 has a lower brightness at the position of the first horn shape portion 1024 and the second horn shape portion 1026. Therefore, the first arcuate columnar structure 404 and the second arcuate columnar structure 406 of the light guide plate 402 of the embodiment can also reduce the brightness of the light emitted from the second upper surface 1024a and the third upper surface 1026a. The difference in brightness of the light emitted from the first upper surface 1022a, and uniformizing the surface light source emitted from the first upper surface 1022a, the second upper surface 1024a, and the third upper surface 1026a of the light guide plate 402.

In other embodiments of the present invention, the first microstructure and the second microstructure of the light guide plate are not limited to a prismatic structure or a circular columnar structure, and may also be an uneven plane or a dot-like structure, or A microstructure having optical properties such as refraction, reflection, or scattering. Alternatively, the first microstructure and the second microstructure may be different structures, for example, the first microstructure includes a prismatic structure, a circular columnar structure, a dot-like structure or an uneven plane, and the second microstructure includes a prismatic structure. , arc-column structure, dot-like structure or uneven plane.

The backlight module of the present invention is not limited to having two sets of light sources, and may have only a single group of light sources. Please refer to FIG. 12, which is a cross-sectional view of a backlight module according to a fifth preferred embodiment of the present invention. As shown in FIG. 12, in contrast to the first embodiment, the backlight module 500 of the present embodiment has only the first light source 502 and does not have the second light source. Also, the light guide plate 504 has only the first horn-shaped portion 1024 and does not have the second horn-shaped portion, and thus has only the first microstructure 506.

In summary, the present invention is provided by placing the first on the second upper surface inclined toward the main body portion. The microstructure and/or the second microstructure is disposed on the third upper surface such that the light emitted from the second upper surface and/or the third upper surface can achieve an atomization effect and avoid from the second upper surface and/or the third The light emitted from the upper surface is concentrated toward the two locations. Thereby, the brightness of the light emitted from the second upper surface and/or the third upper surface can be close to the brightness of the light emitted from the first upper surface of the main body portion to uniformize the surface light source emitted from the upper surface of the light guide plate. .

The above descriptions are only preferred embodiments of the present invention, and all changes and modifications made by the scope of the patent application of the present invention should be covered by the present invention.

100‧‧‧Backlight module

102‧‧‧Light guide plate

1022‧‧‧ Main body

1022a‧‧‧ first upper surface

1022b‧‧‧First lower surface

1024‧‧‧ first flare shape

1024a‧‧‧Second upper surface

1024b‧‧‧second lower surface

1024c‧‧‧ first light surface

1026‧‧‧second horn shape

1026a‧‧‧ third upper surface

1026b‧‧‧ Third lower surface

1026c‧‧‧Second entrance

104‧‧‧First light source

104a‧‧‧The first glazing

106‧‧‧Second light source

106a‧‧‧second glazing

108‧‧‧First microstructure

108a‧‧‧First prismatic structure

110‧‧‧Second microstructure

110a‧‧‧Second prismatic structure

200‧‧‧Backlight module

202‧‧‧Light guide plate

204‧‧‧First prismatic structure

206‧‧‧Second prismatic structure

300‧‧‧Backlight module

302‧‧‧Light guide plate

304‧‧‧First microstructure

304a‧‧‧First circular columnar structure

306‧‧‧Second microstructure

306a‧‧‧Second arc columnar structure

400‧‧‧Backlight module

402‧‧‧Light guide plate

404‧‧‧First circular columnar structure

406‧‧‧Second arc columnar structure

500‧‧‧Backlight module

502‧‧‧First light source

504‧‧‧Light guide plate

506‧‧‧First microstructure

C1‧‧‧ first curve

C2‧‧‧second curve

C3‧‧‧ third curve

C4‧‧‧fourth curve

C5‧‧‧ fifth curve

Figure 1 is a top plan view of a first preferred embodiment of the present invention.

Fig. 2 is a schematic cross-sectional view taken along line A-A' of Fig. 1.

Figure 3 is a side elevational view of a portion of the backlight module of the first preferred embodiment of the present invention.

Fig. 4 is a view showing the relationship between the position and the brightness of the backlight module having the horn shape but not having the first microstructure in the direction along the line A-A' of Fig. 1.

Fig. 5 is a view showing the relationship between the position and the brightness of the backlight module of the first preferred embodiment of the present invention along the direction of the section line A-A' of Fig. 1.

FIG. 6 is a schematic side view of a backlight module according to a second preferred embodiment of the present invention.

Fig. 7 is a view showing the relationship between the position and the brightness of the backlight module of the second preferred embodiment of the present invention along the direction of the section line A-A' of Fig. 1.

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

Figure 9 is a cross-sectional view of the backlight module of the third preferred embodiment of the present invention along the first Figure A schematic diagram of the relationship between the position and the brightness in the direction of A-A'.

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

Fig. 11 is a view showing the relationship between the position and brightness of the backlight module of the fourth preferred embodiment of the present invention along the line A-A' of Fig. 1.

FIG. 12 is a cross-sectional view showing a backlight module according to a fifth preferred embodiment of the present invention.

100‧‧‧Backlight module

102‧‧‧Light guide plate

1022‧‧‧ Main body

1024‧‧‧ first flare shape

1024a‧‧‧Second upper surface

1026‧‧‧second horn shape

1026a‧‧‧ third upper surface

108‧‧‧First microstructure

108a‧‧‧First prismatic structure

110‧‧‧Second microstructure

110a‧‧‧Second prismatic structure

Claims (17)

A light guide plate having a horn-shaped structure, comprising: a main body portion having a first upper surface and a first lower surface parallel to each other; and a first trumpet-shaped portion having a second upper surface The first horn-shaped portion is connected to one side of the main body portion, and the thickness of the first horn-shaped portion is larger as the distance from the main body portion is larger, so that the second horn-shaped portion is the second The upper surface is an inclined surface, wherein the second upper surface of the first horn shaped portion has a plurality of first microstructures. A light guide plate having a horn-shaped structure according to claim 1, wherein the first microstructures comprise a plurality of prismatic structures parallel to each other. The light guide plate having a horn-shaped structure according to claim 2, wherein the prismatic structures are perpendicular to a side of the second upper surface and the main body portion. The light guide plate having a horn-shaped structure according to claim 2, wherein the prismatic structures are parallel to one side of the second upper surface and the main body portion. The light guide plate having a horn-shaped structure according to claim 1, wherein the first microstructures comprise a plurality of arcuate columns parallel to each other. a light guide plate having a horn-shaped structure according to claim 5, wherein the circular arc columns The structure is perpendicular to a side of the second upper surface that is connected to the body portion. The light guide plate having a horn-shaped structure according to claim 5, wherein the arcuate columnar structures are parallel to one side of the second upper surface and the main body portion. The light guide plate having a horn-shaped structure according to claim 1, further comprising a second horn-shaped portion having a third upper surface, the second horn-shaped portion being connected to the other side of the main body portion, and the first The thickness of the second horn shaped portion is larger as the distance from the main body portion is larger, so that the third upper surface of the second horn shaped portion is an inclined surface, wherein the third upper portion of the second horn shaped portion The surface has a plurality of second microstructures. A backlight module includes: a light guide plate, comprising: a main body portion having a first upper surface and a first lower surface parallel to each other; and a first horn shaped portion having a second upper surface and a a second lower surface and a first light incident surface, the first horn-shaped portion is connected to one side of the main body portion, and a thickness of the first horn-shaped portion is larger as a distance from the main body portion is larger. The second upper surface of the first horn shaped portion is an inclined surface, wherein the second upper surface of the first horn shaped portion has a plurality of first microstructures; and at least one first light source facing the first A light setting. The backlight module of claim 9, wherein the first microstructures comprise a plurality of prismatic structures parallel to each other. The backlight module of claim 10, wherein the prismatic structures are perpendicular to a side of the second upper surface that is connected to the body portion. The backlight module of claim 10, wherein the prismatic structures are parallel to a side of the second upper surface that is connected to the body portion. The backlight module of claim 9, wherein the first microstructures comprise a plurality of arcuate columns parallel to each other. The backlight module of claim 13, wherein the arcuate columnar structures are perpendicular to a side of the second upper surface that is connected to the body portion. The backlight module of claim 13, wherein the arcuate columnar structures are parallel to one side of the second upper surface and the body portion. The backlight module of claim 9, further comprising a second horn shaped portion having a third upper surface and a second light incident surface, the second horn shaped portion being coupled to the other side of the main body portion And the thickness of the second horn shape portion is larger as the distance from the main body portion is larger, so that the third upper surface of the second horn shape portion is a tilt table a surface, wherein the third upper surface of the second horn shaped portion has a plurality of second microstructures. The backlight module of claim 16, further comprising at least one second light source disposed facing the second light incident surface.