TW201341903A - Backlight module, and light guide, and display thereof - Google Patents

Abstract

A backlight module is provided, including a light source and a light guide. The light source provides a first light. The light guide includes a light entering surface, a reflective surface and a light existing surface. A guiding recess is formed on the light entering surface. The light source is corresponding to the guiding recess. The first light enters the light guide through the guiding recess, and is modulated into a second light thereby. The second light is reflected by the reflective surface, and is modulated into a third light and emitted from the light existing surface.

Description

Backlight module, light guide plate and display thereof

The present invention relates to a backlight module, and more particularly to a backlight module that can omit a cymbal.

The conventional backlight module includes a light-emitting diode light source, a light guide plate, a diffusion sheet, a top sheet and a lower jaw piece. The diffusion sheet is placed above the light guide plate to uniformly atomize the light emitted from the light guide plate. The lower jaw is placed over the diffuser to homogenize the vertical light and lead to the front of the backlight module. The upper cymbal is placed above the lower cymbal to homogenize the horizontal light and lead to the front of the backlight module. The diffuser, the upper and lower jaws all increase the brightness. However, the use of so many optical films, the purpose is to increase the intensity of the front light, but also because the light needs to penetrate these optical films to reduce the energy, assuming that the diffuser and the upper and lower cymbals have a penetration rate of 90%, the injection The light energy of the light-emitting surface of the light guide plate is 1. When the light is increased in intensity by the positive angle of the optical film, the energy is also reduced to 72.9%.

The present invention provides a backlight module for solving the problems of the prior art, including a light source and a light guide plate. The light source provides a plurality of first rays. The light guide plate includes a light incident side, a light reflecting surface and a light emitting surface. A light guiding groove is formed on the light incident side, and the light source corresponds to the light guiding groove, wherein the first light rays are in the light guiding groove The light guide plate enters the plurality of light rays, and the second light rays are reflected by the light reflecting surface to form a plurality of third light rays, and are emitted toward the light emitting surface.

The invention also provides a light guide plate, comprising a light guide plate body, the light guide plate body comprises a light incident side, a light reflecting surface and a light emitting surface, wherein a light guiding groove is formed on the light incident side, wherein the plurality of first light rays are The light guiding groove enters the light guide plate to form a plurality of second light rays, and the second light rays are reflected by the reflecting surface to form a plurality of third light rays, and are emitted toward the light emitting surface.

The present invention also provides a display comprising a display panel and a backlight module as described above, wherein the display panel and the backlight module are stacked.

The backlight module of the embodiment of the present invention is used to replace the upper and lower cymbals of the prior art through the backlight design method such as the light guiding groove, the reflecting portion, the reflective microstructure, and the light-emitting microstructure, thereby avoiding light penetration. The energy loss in the case of smashing, and the number of components of the backlight module of the embodiment of the present invention are small, so that assembly can be facilitated.

Referring to FIG. 1A, a backlight module 1 according to a first embodiment of the present invention includes a light source 10, a light guide plate (light guide plate body) 20, a reflection sheet 30, and a diffusion sheet 40. Light source 10 provides a plurality of first rays 11. The light guide plate 20 is disposed between the reflection sheet 30 and the diffusion sheet 40.

The light guide plate 20 includes a light incident side 21, a light reflecting surface 22, and a light exiting surface 23. A light guiding groove 211 is formed on the light incident side 21, and the light source 10 corresponds to the light guiding groove 211.

The first light rays 11 enter the light guide plate 20 in the light guiding groove 211, and are refracted into the plurality of second light rays 12 via the light guiding grooves 211. It is worth noting that the light rays parallel to the horizontal direction are used as a reference ( The angle δ between the second ray 12 and the horizontal direction Y converges between ±20°, and the second ray 12 is reflected by the reflective surface 22 into a plurality of third rays 13 The light exit surface 23 is emitted.

The first light ray 11 includes a first incident light 111 and a second incident light 112. The first incident light 111 enters the light guide plate 20 in the light guide groove 211. The light guide groove 211 includes a light reflecting portion 212. The first incident light 111 is reflected by the light reflecting portion 212 to become the first outgoing light 121 of the plurality of second light rays 12, and the first outgoing light 121 is reflected by the reflective surface 22 into the third light rays 13 to be emitted toward the light. Face 23 is shot.

In the above embodiment, the light guiding groove 211 includes an aspherical structure 213, and the second incident light 112 of the first light rays 11 passes through the aspherical structure 213 to enter the light guide plate to become the plurality of second light rays 12 The second outgoing light 122 is reflected by the reflective surface 22 into the third light rays 13 and is emitted toward the light exit surface 23 .

In the first embodiment, the light guide plate 20 is a wedge plate, and the reflective surface 22 and the light exit surface 23 have a wedge angle θ.

A plurality of reflective reflective structures 221 are formed on the reflective surface 22 . Referring to FIG. 1B , each reflective microstructure 221 includes a low beam end surface 222 and a high beam end surface 223 . The low beam end surface 222 is adjacent to the high beam end surface 223 . A high beam end angle α is formed between the high beam end surface 223 and the reflecting surface 22 by 55°-θ-δ. A near-light end face angle β between the low beam end surface 222 and the reflective surface 22 is θ+δ. The width-height (w1/h1) ratio of each reflective microstructure is 4.9 to 5.6.

Through the design of the light guiding groove 211, the light reflecting portion 212 and the reflective microstructure 221 of the first embodiment of the present invention, the third light rays 13 and a first plane (XZ plane) can be parallel to each other to achieve a vertical direction. The light is uniformized, so that the lower jaw of the prior art can be omitted instead. The backlight module 1 of the first embodiment can be used in combination with the upper cymbal of the prior art, and the light uniformity in the horizontal direction can be achieved by the upper cymbal of the prior art.

The reflective sheet 30 may be replaced by a reflective coating or other types of reflective means, or may be omitted, and the above disclosure does not limit the invention.

Fig. 2A is a perspective view showing a light guide plate 20 according to a modification of the first embodiment of the present invention, and Fig. 2B is a view showing a detailed structure of the light exiting microstructure in Fig. 2A. Referring to FIGS. 2A and 2B, in a modification of the first embodiment of the present invention, a plurality of light-emitting microstructures 231 are formed on the light-emitting surface 23, and the third light rays 13 pass through the light-emitting microstructures 231. The plurality of fourth rays 14 are modulated by the light exiting microstructure 231 and parallel to a second plane (YZ plane) that is perpendicular to the second plane. Since the light-emitting microstructure 231 of the embodiment of FIGS. 2A and 2B can achieve uniform light in the horizontal direction, the conventional technique can be omitted instead. In this embodiment, the horizontal divergence angle of the light before unmodulation is 39 degrees, and the width-height (w2/h2) ratio of each light-emitting microstructure 231 is 1.2-1.6. The curved surface of the light-emitting microstructure 231 can be designed for the ray angle by SNELL's law.

The backlight module of the embodiment of the present invention is used to replace the upper and lower cymbals of the prior art through the backlight design method such as the light guiding groove, the reflecting portion, the reflective microstructure, and the light-emitting microstructure, thereby avoiding light penetration. The energy loss in the case of smashing, and the number of components of the backlight module of the embodiment of the present invention are small, so that assembly can be facilitated.

Referring to FIG. 3, a backlight module 2 according to a second embodiment of the present invention is shown, characterized in that the light reflecting portion 212 includes a sawtooth structure 214. The serrated structure 214 can further reduce the thickness of the light guide plate while maintaining a good light parallelization effect.

Referring to FIG. 4, a backlight module 3 according to a third embodiment of the present invention is shown. The light guide plate 20' is not a wedge plate but is a flat plate. In the third embodiment of the present invention, a proper design guide is adopted. The curved surface of the light groove and the light reflecting portion, and the angle of the reflective microstructure, can also achieve uniformity of light in the vertical direction, instead of omitting the lower jaw of the prior art. The above disclosed light guide plate type does not limit the invention.

The present invention provides an embodiment of a display including the above backlight module. The display includes a display panel, and the backlight module is stacked on the display panel, and the display panel can be a liquid crystal display panel.

Although the present invention has been described above in terms of the preferred embodiments thereof, it is not intended to limit the invention, and those skilled in the art can make some modifications and refinements without departing from the spirit and scope of the invention. Therefore, the scope of the invention is defined by the scope of the appended claims.

1, 2, 3. . . Backlight module

10. . . light source

11. . . First light

111. . . First incident light

112. . . Second incident light

12. . . Second light

121. . . First light

122. . . Second exit light

13. . . Third light

14. . . Fourth light

20, 20’. . . Light guide

twenty one. . . Light side

211. . . Light guide groove

212. . . Reflection section

213. . . Aspheric structure

214. . . Serrated structure

twenty two. . . Reflective surface

221. . . Reflective microstructure

222. . . Low beam end face

223. . . High beam end face

twenty three. . . Glossy surface

231. . . Light-emitting microstructure

30. . . A reflective sheet

40. . . Diffusion sheet

1A is a backlight module showing a first embodiment of the present invention;

Figure 1B shows the detailed structure of the reflective microstructure;

2A is a perspective view showing a light guide plate according to a modification of the first embodiment of the present invention;

Figure 2B shows the detailed structure of the light-emitting microstructure in Figure 2A;

3 is a backlight module showing a second embodiment of the present invention;

Fig. 4 is a view showing a backlight module of a third embodiment of the present invention.

1. . . Backlight module

10. . . light source

11. . . First light

111. . . First incident light

112. . . Second incident light

12. . . Second light

121. . . First light

122. . . Second exit light

13. . . Third light

14. . . Fourth light

20. . . Light guide

twenty one. . . Light side

211. . . Light guide groove

212. . . Reflection section

213. . . Aspheric structure

twenty two. . . Reflective surface

221. . . Reflective microstructure

222. . . Low beam end face

223. . . High beam end face

twenty three. . . Glossy surface

30. . . A reflective sheet

40. . . Diffusion sheet

Claims (27)

A backlight module includes: a light source for providing a plurality of first light rays; and a light guide plate including a light incident side, a light reflecting surface, and a light emitting surface, wherein a light guiding groove is formed on the light incident side, the light source pair a light guiding groove, wherein the first light enters the light guide plate in the light guiding groove, and becomes a plurality of second light rays, and the second light rays are reflected by the reflective surface to become a plurality of third light rays, and The light surface is shot. The backlight module of claim 1, wherein the first light rays are refracted by the light guiding grooves into the second light rays, and an angle δ between the second light rays and the horizontal direction converges to ± Between 20°. The backlight module of claim 2, wherein the light guiding groove comprises an aspherical structure. The backlight module of claim 2, wherein the light guiding groove comprises a light reflecting portion. The backlight module of claim 2, wherein the light guide plate is a wedge plate, and the reflective surface and the light exit surface have a wedge angle θ. The backlight module of claim 5, wherein the plurality of reflective microstructures are formed on the reflective surface, each reflective microstructure comprising a low beam end surface and a high beam end surface, the low beam end surface adjoining the high beam The end surface, the angle between the high beam end surface and a high beam end surface of the reflecting surface is 55°-θ-δ. The backlight module of claim 6, wherein an angle β between the low beam end surface and a low beam end surface of the reflective surface is θ+δ. The backlight module of claim 6, wherein each of the reflective microstructures has an aspect ratio of 4.9 to 5.6. The backlight module of claim 1, wherein the third light rays are parallel to a first plane. The backlight module of claim 9, wherein a plurality of light-emitting microstructures are formed on the light-emitting surface, and the third light rays pass through the light-emitting microstructures to form a plurality of fourth light rays. Modulation of the light-emitting microstructure, the fourth rays are parallel to a second plane, the first plane being perpendicular to the second plane. The backlight module of claim 10, wherein each of the light-emitting microstructures has an aspect ratio of 1.2 to 1.6. The backlight module of claim 4, wherein the light reflecting portion comprises a sawtooth structure. The backlight module of claim 1, wherein the light guide plate is a flat plate. The backlight module of claim 1, further comprising a diffusion sheet corresponding to the light emitting surface. The backlight module of claim 1, further comprising a reflective sheet corresponding to the reflective surface. A light guide plate includes: a light guide plate body, comprising a light incident side, a light reflecting surface and a light emitting surface, wherein a light guiding groove is formed on the light incident side, wherein the plurality of first light rays enter the light guiding groove The light guide plate is a plurality of second light rays, and the second light rays are reflected by the light reflecting surface to form a plurality of third light rays, and are emitted toward the light emitting surface. The light guide plate of claim 16, wherein the first light rays are refracted by the light guide groove into the second light rays, and an angle δ between the second light rays and the horizontal direction converges to ±20 ° between. The light guide plate of claim 17, wherein the light guide groove comprises an aspherical structure. The light guide plate of claim 17, wherein the light guiding groove comprises a light reflecting portion. The light guide plate of claim 17, wherein the light guide plate is a wedge plate, and the reflective surface and the light exit surface have a wedge angle θ. The light guide plate of claim 20, wherein a plurality of reflective microstructures are formed on the reflective surface, each reflective microstructure comprising a low beam end surface and a high beam end surface, the low beam end surface adjoining the high beam end surface The angle between the high beam end surface and a high beam end surface of the reflecting surface is 55°-θ-δ. The light guide plate according to claim 21, wherein an angle β between the low beam end surface and a low beam end surface of the reflective surface is θ+δ. The light guide plate of claim 21, wherein each of the reflective microstructures has an aspect ratio of 4.9 to 5.6. The light guide plate of claim 19, wherein the third light rays are parallel to each other on a first plane. The light guide plate of claim 19, wherein a plurality of light-emitting microstructures are formed on the light-emitting surface, and the third light rays pass through the light-emitting microstructures to form a plurality of fourth light rays, and receive the light. The modulation of the microstructures, the fourth rays being parallel to each other on a second plane, the first plane being perpendicular to the second plane. The light guide plate of claim 25, wherein each of the light-emitting microstructures has an aspect ratio of 1.2 to 1.6. A display comprising: a display panel; and a backlight module as claimed in claim 1 , which is laminated with the display panel.