JP2007080596A - Sidelight type light guide plate for back light module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve light emitting luminance of a light guide plate by reducing energy loss caused by frequent reflection of light of a light source by a reflection thin piece by preventing light leaking outside of a light guide from irradiating to a reflection thin piece. <P>SOLUTION: A plurality of light guides are formed in the reflecting surface of the light guide plate. An auxiliary light guide is also formed on one side of the light guides. The auxiliary light guide is arranged to be molded along the light guide. Thus, the leak light of the light source that does not enter the light guide plate by the guidance of the light guide is received through the auxiliary light guide which matches. That is, the leak light is again led into the light guide plate. Finally, the chance that the leak light projects on the reflection thin piece is reduced, and the energy loss of the light caused during projection of the light on the reflection thin piece is reduced. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a light guide plate for a sidelight type backlight module.

The backlight module mainly requests a light guide plate to produce a planar light source.
The light guide plate itself has excellent light transmission. Generally, it is made of almost optical grade acrylic (PMMA) material and has one light exit surface, one reflection surface, and at least one entrance surface. From early on, the design of the light guide point (Pattern) was formed on the surface of the reflecting surface, and the light was reflected by the light reflection of the light source, but since then, other designs that guide the light have been developed.

The light guide plate 1 includes a light exit surface 11, a reflective surface 12 facing the light exit surface 11, a light exit surface 11, and an incident surface 13 formed from at least one side connected to the reflective surface 12. A plurality of V-shaped light guides 121 are formed on the reflecting surface 12. As shown in FIG. 1, the light guide 121 protrudes out of the reflecting surface 12. Alternatively, as shown in FIG. 2, the light guide 121 is recessed into the reflecting surface 12. After the light from the lamp 2 enters the inside of the light guide plate 1 from the incident surface 13, the direction of the light is changed by the light guide 12 while the portion of the light is transmitted through the reflecting surface 12. Do it. In other words, the light is guided back into the light guide plate 1 again. . Therefore, the chance that the light is projected on the reflection flakes 3 is reduced, and the light is reflected by the reflection flakes 3 to reduce the energy consumption of the invited light.

However, as shown in FIGS. 1 and 2, the light guide 121 is formed on the reflection surface 12 of the light guide plate 1 so that the light guide 121 is formed on the reflection surface of the traditional light guide plate. Compared to, the manufacturing process, light reflection, and guiding effect are good, but still not as ideal. The main causes are as follows. As shown in FIGS. 3 and 4, while the light from the light source is projected onto the light guide 121, only a portion of the light is refracted and reflected via the light guide 121. Actually, in the process in which the light source projects onto the light guide 121, when the light is refracted from the first slope 1211 of the light guide 121 to the second slope, the light from the second slope 1212 The light is reflected back to the light guide plate 1, but the other part of the light is also transmitted through the second inclined surface 1212 and irradiated to the reflective flake 3. If the reflection flakes 3 do not reflect these lights, they cannot enter the light guide plate again. As a result, energy is always lost when light shines on the reflecting flakes and is reflected. Such a phenomenon is a problem that was initially invited due to insufficient correlated design.

Accordingly, a main object of the present invention is to provide a light guide plate for a sidelight type backlight module. Such a light guide plate is made of an optically transparent material such as optical grade acrylic (PMMA).

While the light from the light source is transmitted in the light guide plate, the chance that the transmitted and emitted light irradiates the reflection flake through the reflection surface of the light guide plate is reduced. In other words, the light emission intensity of the light guide plate is improved by reducing the energy loss caused by the frequent reflection of the reflection flakes.

The light guide plate has a light exit surface, a reflective surface at a corresponding position of the light exit surface, a light exit surface, and at least one incident surface connected to the reflective surface. On such a reflective surface, multiple light guides parallel to the incident surface are formed. An auxiliary light guide is also formed on one side of the light guide. The auxiliary light guide is shaped to match along the light guide.

Then, while the light from the light source is transmitted and emitted through the reflection surface of the light guide plate, the light guides the light on the reflection surface to guide the light back to the light guide plate. Even though the light from the light guide did not return smoothly to the light guide plate, it was received by the matched auxiliary light guide. Guide the light back to the light guide plate again by the guidance of the auxiliary light guide. Eventually, light that leaks out of the light guide is prevented from irradiating the reflective flakes. There is no risk of energy loss caused by the frequent reflection of the light from the light source.

According to the present invention, the second light receiving slope of the auxiliary light guide may adopt a concave curved surface. Therefore, when the light from the light source is reflected and guided back to the inside of the light guide plate, there is a light collecting effect. Concentrate the light from the light source to improve the light emission brightness.

Further, according to the present invention, when the light guide formed on the reflecting surface protrudes from the outer surface of the reflecting surface, the length of the length of the matched auxiliary light guide protruding from the reflecting surface is such that the light guide protrudes from the reflecting surface. It should not be smaller than a certain length. Since the light receiving effect of light leaking from the light guide is the best, the light from the light source is reliably guided to the auxiliary light guide.

In order to understand the objects, features, and effects of the present invention, a more detailed description will be given below with reference to specific examples.
In summary, the present invention forms a plurality of auxiliary light guides on the reflecting surface of the light guide plate. The auxiliary light guide is formed along one side of the light guide on the reflecting surface. Then, even if the light from the light source does not return smoothly to the light guide plate by the light guide, the light leaking out of the light guide through the auxiliary light guide is once again guided back to the inside of the light guide plate. For that reason, light that leaks out of the light guide is prevented from irradiating the reflective flakes. The light emission of the light guide plate is improved by reducing the energy loss caused by the frequent reflection of the reflection flakes.

Please see Figure 5 first. The present invention relates to a light guide plate for a sidelight type backlight module. Such a light guide plate 4 is made of a material having excellent light transmission properties, and includes a light exit surface 41, a reflective surface 42 at a corresponding position of the light exit surface 41, at least one incident surface 43 connected to the light exit surface 41, and the reflective surface 42. There is. A plurality of light guides 421 protruding from the reflecting surface 42 are formed on the reflecting surface 42. The light guides 421 are formed along the parallel direction of the incident surface 41. An auxiliary light guide 422 is also formed on one side of the light guide 421 (one side far from the incident surface 43). The auxiliary light guide 422 has a first light receiving slope 4221 and a second light receiving slope 4222 and is formed along the light guide 421 to match.

See Figure 6. While the incident surface 43 receives the light from the lamp 5 and transmits the light from the light source to the inside of the light guide plate 4, the light that passes through and exits the reflective surface 42 and enters the light guide 421 is partially After being refracted and reflected by the light guide 421, it marches along the direction of the light exit surface 41. Other partial lights that cannot be smoothly reflected from the light guide 421 to the inside of the light guide plate 4 are transmitted and emitted outside the light guide 421. The light transmitted and emitted through the light guide 421 is received by the auxiliary light guide 422 on one side of the light guide 421. In addition, the light is refracted by the first light receiving slope of the auxiliary light guide 422. The refracted light is guided to the second light receiving slope 4222. Next, the second light receiving slope 4222 reflects the light to the light guide plate 4 once again. In other words, the light is guided to march in the direction of the light exit surface 41 of the light guide plate 4.

According to the present invention, the auxiliary light guide 422 is formed on one side of the light guide 421 on the reflecting surface 42, so that light leaking from the light guide 421 is immediately guided to the light guide plate 4 by the guidance of the auxiliary light guide 422. Return. Eventually, light that leaks out of the light guide 421 is prevented from irradiating the reflective thin piece 6. The light emission of the light guide plate 4 is improved by reducing the energy loss caused by the frequent reflection operation of the reflection flakes 6 by the light from the light source.

See Figure 7. In the practice of the present invention, it can be seen that it is best if the length of the auxiliary light guide 423 protruding out of the reflecting surface 42 of the light guide plate 4 is designed to be smaller than the length of the matched light guide 421. Therefore, the light leaking from the light guide 421 can be received effectively, and the auxiliary light guide 422 reliably guides the light.

See Figure 8. According to the present invention, the second light receiving inclined surface 4222 of the auxiliary light guide 423 may adopt the shape of the concave curved surface 4223. Therefore, when the light from the light source is refracted by the first light receiving slope 4221 and reflected here, the concave curved surface 4223 also has a condensing reflection effect, so that the light is reflected back to the light guide plate 4 and returned. , The effect of concentration is demonstrated, and the expression of light emission luminance is improved.

According to the present invention, the formation of the auxiliary light guide 422 has the effect of guiding the light of the light source. The light guide 421 on the reflection surface 42 of the light guide plate 4 may adopt a design of a recessed light guide 421 ′ so as to be recessed in the reflection surface 42. Further, an auxiliary light guide 422 is formed on one side of the recessed light guide 421 '. See Figure 9. The auxiliary light guide is molded along one side of the recessed light guide 421 '. Then, the light of the portion that does not return smoothly to the light guide plate 4 is received by the action of the matched auxiliary light guide 422 by the guide of the recessed light guide 421 ′. The light leaking out of the concave light guide 421 ′ is guided once again into the light guide plate 4. In other words, the chance of light projecting on the reflective flakes 6 is reduced, and the energy loss of the light caused by the reflection operation of the reflective flakes 6 is reduced.

See Figure 10. When the light guide plate 4 adopts the recessed light guide 421 ′, of course, the auxiliary light guide 422 can be applied using the concave curved surface 4223. Therefore, there is a reflection operation in which light passes through the concave curved surface 4223 and has the effect of condensing and reflecting light. The effect of concentrating and guiding the light from the light source is achieved.
Further, according to the present invention, the shape of the light guide plate 4 is not limited to a flat plate shape. The selection and use of a wedge-shaped plate does not adversely affect the application of the present invention. As shown in Figure 11-14, the light guiding effect of the light source and its effects are the same as described above.

It is an explanatory diagram of a light guide plate of a known backlight module. It is an explanatory view of another light guide plate of a known backlight module. In Fig. 1, the operation of light from the light source is explained. In FIG. 2, it is explanatory drawing of the operation | movement of the light of a light source. It is a section explanatory view of the present invention. In FIG. 5, it is operation explanatory drawing of the light of a light source. FIG. 4 is an explanatory diagram of an embodiment of an auxiliary light guide according to the present invention. It is another example explanatory drawing of an auxiliary light guide according to the present invention. FIG. 4 is a cross-sectional explanatory drawing employing a recessed light guide according to the present invention. FIG. 4 is a cross-sectional explanatory drawing that adopts another recessed light guide according to the present invention. Each cross-sectional view applied to a wedge-shaped light guide plate according to the present invention. Each cross-sectional view applied to a wedge-shaped light guide plate according to the present invention. Each cross-sectional view applied to a wedge-shaped light guide plate according to the present invention. Each cross-sectional view applied to a wedge-shaped light guide plate according to the present invention.

Explanation of symbols

1 Light guide plate
11 Light emitting surface 12 Reflecting surface
13 Incident surface 121 Light guide
2 Lamp 3 Reflective flake
1211 1st slope 1212 2nd slope 4 Light guide plate
41 Light emitting surface 42 Reflecting surface
43 Incident surface
421 Light guide 421 'Light guide
422 Auxiliary light guide 423 Auxiliary light guide 4221 First light receiving slope
4222 Second light receiving slope 4223 Concave surface
6 Reflective flakes

Claims (7)

  In the light guide plate for the sidelight type backlight module, the light guide plate has a light exit surface, a reflection surface at a corresponding position of the light exit surface, the light exit surface, and at least one incident surface connected to the reflection surface. On such a reflective surface, a light guide is formed along the parallel direction of the incident surface. An auxiliary light guide is also formed on one side of the light guide that protrudes out of the reflective surface. A light guide plate for a backlight module of a side light type, characterized in that the auxiliary light guide has a first light receiving slope and a second light receiving slope, and is molded and installed so as to match along the light guide.   The light guide plate for a sidelight type backlight module according to claim 1, wherein the length of the auxiliary light guide protruding from the reflecting surface is not smaller than the length of the matched light guide protruding from the reflecting surface. Sidelight type light guide plate for backlight module.   The light guide plate for a side light type backlight module according to claim 1, wherein the second light receiving inclined surface of the auxiliary light guide is a concave curved surface.   The light guide plate for a sidelight type backlight module according to claim 1, wherein the length of the auxiliary light guide protruding from the reflecting surface is not smaller than the length of the matched light guide protruding from the reflecting surface. A light guide plate for a sidelight type backlight module, wherein the second light receiving slope of the auxiliary light guide is a concave curved surface.   The side light type light guide plate for a backlight module according to claim 1 or 3, wherein the light guide matched with the auxiliary light guide is a concave light guide recessed on the reflecting surface. Light-type light guide plate for backlight module.   6. The light guide plate for a side light type backlight module according to claim 1, wherein the light guide plate adopts a flat plate shape.   6. The light guide plate for a side light type backlight module according to claim 1, wherein the light guide plate employs a wedge-shaped plate.

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