TW557374B - Light-guiding structure of backlight module - Google Patents

Abstract

A light-guiding structure of backlight module is disclosed, which is composed of a light-guiding plate, a light source, a reflective plate and a prism sheet. The light-guiding plate has plural light-guiding patterns concentric with the light source and arranged in the arc of concentric circle on one surface of the top surface or the bottom surface. The prism sheet is disposed on the surface other than the surface on which the light-guiding plate is associated with the reflective plate. One of the top surface or bottom surface of the prism sheet has plural light-converging patterns with the same arrangement mode as that of the light-guiding pattern of the light-guiding plate, so that the light emitted from the light source can be converged and exits toward the normal direction of the light-guiding plate through the action of the light-guiding pattern and light-converging pattern.

Description

557374

[Technical market] The guest film t :: is related to the light guide structure of a backlight module, in particular, the light guide junction 2 of the backlight module is focused from the normal direction of the light guide plate [previous technology] such as Fig. 7 is a top view of a conventional backlight module, which is mainly provided on the bottom surface of the light guide plate 71 with a plurality of linear light guide patterns 7 2 arranged in parallel for the light source 7 3 The emitted light is appropriately directed to the liquid crystal module (not shown). Please refer to FIG. 7 'Because the light of the light source 72 is in the form of radial diffusion, when the light L is incident on the light guide pattern 72, an angle α is generated between the light guide L and the light guide pattern 72, and a refracted light L is generated. 1 Diffusion outwards, causing brightness degradation. In order to solve this problem, it is necessary to increase the brightness or number of light sources, but 'increasing the brightness or number of light sources will lead to an increase in power consumption. Referring to FIG. 8 again, when the light L is directed to the light guide pattern 72, since the light guide pattern 7 2 is in a v-shaped groove shape, a reflected light L 2 is emitted, and the reflected light L 2 and the A predetermined exit angle A is formed between the normals of the light guide plate 71. The closer the exit angle stone is to the normal line A of the light guide plate 71, the better the brightness of the forward light generated in the direction A, otherwise, the weaker the brightness of the forward light. In order to direct the exit angle, it is hoped that the light emitted by the backlight module can approach the normal direction A of the light guide plate 71. At present, a commonly used method is to use a light guide plate.

557374 V. Description of the invention (2) 7 A layer of brightness enhancement film 8 is provided. Taking the brightness enhancement film manufactured by 3M Company as an example, a light-condensing pattern 8 1 arranged in a straight line is arranged on the bottom surface of the brightness enhancement film 8. The light-concentrating pattern 81 is in a V-shaped groove shape, as shown in FIG. 8. With the condensing pattern 8 1 parallel to the light guide pattern 7 2, the reflected light L 2 is generated by the condensing pattern 8 1 to generate the outgoing light L 3 close to the normal direction A of the light guide plate 7 1. Enhance the brightness of forward light. However, the phenomenon of brightness attenuation caused by the outward diffusion of refracted light L 1 occurs before the light enters the brightness enhancement film 8, that is, only a part of the light emitted by the light source 73 can enter the brightness enhancement film 8 to generate the required positive To the light, therefore, the backlight module after adding the brightness enhancement film 8 still has a problem of insufficient brightness. Please refer to FIG. 9 again, which is another conventional backlight module, which is mainly provided on the light guide plate 9 1 with a plurality of arc-shaped light guide patterns 9 2 for appropriately guiding the light emitted by the light source 9 3 Liquid crystal module (not shown) 〇Because each light guide pattern 92 is arc-shaped, the angle α between the light L emitted from the light source 93 and the light guide pattern 92 will be close to 90 °, so , Can effectively reduce the problem of diffused attenuation of light due to the generation of refracted light. However, when the light L is incident on the light guide pattern 92, the light guide pattern 92 is in the shape of a V-shaped groove, as shown in FIG. 10, so a reflected light L2 is emitted. Generally speaking, The exit angle / 3 between the reflected light L 2 and the normal direction A of the top surface of the light guide plate 91 is about 30 ° ~ 60 °, and the forward light generated by the light emitted at this angle The brightness is still insufficient.

557374 V. Description of the invention (3) Therefore, due to the external diffusion of the circle, however, 30 ° is sufficient forward light, which can be provided. If the front bright film 8 is installed, it will be caused by the circular pattern 8 1. Only the intersection, and some of the light guide plates 91 and 1 can produce the light guide plate 91 in the figure. It is necessary to use the existing brightness enhancement film. [Objective and effect The light guide film of the backlight module of the present invention has a concentric circular plate, a light-concentrating pattern, and an arc-shaped brightness of ~ 60, so the brightness is still described as having a circular shape. The proliferation and brightness enhancement film can be seen in the light guide centerline B-shaped guide 8 to achieve the attenuation of each light guide map. This one needs to add the effect of a straight arc light pattern light guide plate bright film 8 stack 8 Set a part of the light pattern of the pattern 9 to the enhanced light pattern 9, the parallel light guide 9 2 9 1 with strong angle structure only, as in the latter 2 and the connection 9 2 forward module 2 although β is still increased No backlight. The pattern 9 of the arrangement is close to the guideline of the straight center line. 1 1 The top-view light-concentration structure of the nearly parallel light guide can effectively reduce the brightness of the light to the backlight module, so that the backlight module can obtain the module in the visible range. Condensing Figure 2 The light guide plate parallel to the part B of light guide 9 is shown in the way shown in Figure 8. The utility of the intersection plate 9 1 is drawn. There is still a light concentration plate arranged on the lightening plate 9 1 of sample 8 1 near the center of flat 1. The line's figure is based on the system, and the first one is only in the close form, because the main purpose cannot be improved by 0, which is to solve the above-mentioned light-transmitting structure. An arc-shaped light guide pattern arranged in an arc, and the company " is a light guide pattern provided with a circle and a light guide plate for the circle: the light guide allows the light emitted by the light source to pass through the light guide :: the arrangement pattern to capture the special pattern and focus Figure

Page 6 557374 V. Description of the invention (4) The effect is the same, and the light is emitted from the normal direction of the light guide plate in order to achieve the effect of improving the light guide efficiency. [Technical content] The present invention provides a light guide structure of a backlight module, which is composed of a light guide plate, a light source, a reflection plate, and a brightness enhancement film; the light guide plate is provided on one of the top surface and the bottom surface. There are many light guide patterns, and each of the light guide patterns is in the form of a concentric arc arrangement with the light source as the center; the reflection plate is provided on one of the top surface and the bottom surface of the light guide plate; the brightness enhancement film system The light guide plate is disposed on the other side where the light guide plate is combined with the reflection plate, and one of the top surface and the bottom surface of the brightness enhancement film is provided with a plurality of light condensing patterns in the same arrangement pattern as the light guide pattern of the light guide plate. The above and other objects and advantages of the present invention can be easily understood from the detailed description and accompanying drawings of the selected embodiments below. Of course, the present invention allows some differences in the arrangement or arrangement of other parts, but the selected embodiment is described in detail in this specification and its structure is shown in the drawings. [Detailed description of the embodiment] Please refer to FIG. 1 to FIG. 3, which show the structure of the embodiment of the present invention, which is used for illustration only, and is not subject to such structure in patent applications. limit. As shown in Fig. 1, the light guide structure of the backlight module of this embodiment is mainly composed of a light guide plate 1, a light source 2, a reflection plate 3, and a brightness enhancement film 4.

Page 7 557374 V. Description of the invention (5) The light source 2 is arranged near a corner of the light guide plate 1. The light guide plate 1 is provided with a plurality of light guide patterns 11 on the bottom surface, and each of the light guide patterns 11 is in a concentric arc arrangement with the light source 2 as the center. In this embodiment, each of the light guide patterns The cross-sectional shape of 11 is a convex arc shape, and each of the light guide patterns 11 has a space W, and each of the light guide patterns 11 has a space W, which is closer to the light source 2. The larger the interval W, the smaller the distance W from the light source 2 is. The reflection plate 3 is coupled to the bottom surface of the light guide plate 1 so as to reflect the light emitted from the light guide plate 1 toward the top surface of the light guide plate 1. The brightness enhancement film 4 is provided on the top surface of the light guide plate 1, and the bottom surface of the brightness enhancement film 4 is provided with a plurality of light-concentrating patterns 4 1, and each of the light-concentrating patterns 41 is a circle centered on the light source 2. The concentric arcs are arranged in a pattern, and each of the light-concentrating patterns 41 has an interval W /, and in this embodiment, the intervals W of each of the light-guiding patterns 41 are arranged in the same pattern at an equal distance. And the cross section of each of the condensing patterns 41 is in a convex V-shaped state. In the light guide plate 1 of the present invention, a photoresist is coated on a glass substrate, and then a photoresist square microstructure in a concentric arc arrangement is produced by a yellow light process, and then a curved surface is formed by heating. The microstructure, wherein the diameter of the curved microstructure pattern is about 3 u in ~ 180 um, and its height is about 4 um ~ 70 um, and then the injection molding mold is made by the electroforming turning mold, that is, The light guide plate 1 having the light guide pattern 11 of the concentric circle arrangement can be produced by injection molding. Finally, the light exit angle 0 with the maximum brightness of the light guide plate 1 is measured and used as a reference value for the production of the brightness enhancement film 4. The manufacturing method of the brightness enhancement film 4 is first machined, which will be round.

557374 V. Description of the invention (6) The brightening structure arranged in a circular arc is processed on a metal flat plate. In this embodiment, the brightening structure is a convex V-shaped structure with a height of about 30 um, and The included angle r of the tip is the same as the light exit angle 0 at which the light guide plate 1 has the maximum brightness. Then, placing the PE brightening film 4 on the metal flat plate and applying hot pressing action, the brightening structure arranged in a circle and a circle can be copied on the brightening film 4 to form the required light-concentrating pattern. 4 1. Finally, the brightness enhancement film 4 is combined on the light guide plate 1 in such a manner that the center of the light-concentrating pattern 41 and the circle center of the light-guiding pattern 11 are aligned to obtain the brightness-enhancing film 4 and the light guide plate 1 required by the present invention. structure. Please refer to FIG. 2. Since each light guide pattern 11 is arranged in a concentric arc arrangement with the light source 2, the angle α between the light L emitted from the light source 2 and the light guide pattern 11 will be perpendicular, so There is no problem that the light is diffused outward and attenuated, so that the light L emitted from the light source 2 can be emitted through the reflection of the light guide pattern 11 to obtain a good light guide efficiency. Please refer to FIG. 3 again, since each of the light-concentrating patterns 4 1 of the brightness enhancement film 4 is parallel to each of the light-guiding patterns 11 of the light-guiding plate 1, therefore, when the light L enters the light-guiding plate 1 and guides After the light pattern 1 1, a reflected light L 1 with an emission angle Θ is generated, and the reflected light L 1 is incident on the light-condensing pattern 4 1 of the brightness enhancement film 4, and then is generated by the refraction of the light-condensing pattern 4 1 to be close to The light L 2 emitted in the normal direction A of the light guide plate 1 enables the brightness enhancement film 4 to achieve the effect of enhancing the brightness of the forward light. It is worth noting that the light guide patterns 11 of the light guide plate 1 of the present invention are arranged in a concentric arc with the light source 2. Therefore, the light guide patterns 11 can be used to prevent the light from spreading outward and attenuating. Problem; furthermore, because

Page 9 557374 V. Description of the invention (7) Each of the light-condensing patterns 41 of the brightness enhancement film 4 and each of the light-guiding patterns 1 1 of the light guide plate 1 are arranged in a concentric arc arrangement with the light source 2, so that Each of the light-concentrating patterns 41 guides light toward the normal direction A of the light guide plate 1 and emits the light, thereby achieving the effect of enhancing the brightness of the forward light. Therefore, the backlight module of the present invention can use only a single light source to achieve the required effect. Brightness, which can effectively reduce power consumption and production costs. In summary, since the light guide plate 1 is provided with a plurality of arc-shaped light guide patterns 1 1 centered on the light source 2 and arranged in a concentric arc, and is combined with the light guide plate 1

The brightness-enhancing film 4 of the light plate 1 is provided with a plurality of light-concentrating patterns 4 1 arranged in parallel with the light-guiding pattern 1 1 of the light-guiding plate 1 so that the light emitted by the light source 2 can pass through the light-guiding pattern 11 and the light-condensing pattern 4 1. Function, and is emitted from the normal direction A of the light guide plate 1 to achieve the effect of improving the light guide efficiency.

Of course, there are still many examples of the present invention, in which only the details have changed. Please refer to FIGS. 4 to 6, which are different forms of the light guide pattern 11 of the light guide plate 1 of the present invention. In addition to the convex arc shape described in the first embodiment, the cross-sectional shape of the light guide pattern of the present invention can also be designed as a concave arc shape as shown in FIG. 4. Form; or the form of a concave V-shape as shown in FIG. 5; and the form of a concave V-shape as shown in FIG. 6, so that both can achieve the same as the aforementioned first embodiment Effect. In addition, the interval W / between the light-concentrating patterns of the brightness enhancement film can also adopt a morphological distribution in which the interval W > is larger as the distance to the light source is larger, and the interval W > is smaller as the distance from the light source is larger. Can achieve the same effect as the first embodiment

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Page 557374 Brief Description of Drawings Figure 1 is an exploded perspective view of the structure of the present invention; the figure illustrates the path of light. Figure 2 is a top view of the present invention; the figure shows the light and light guide patterns. Vertical pattern 3 is a schematic diagram of the light path of the present invention. Figure 4 is a second embodiment of the light guide pattern of the present invention. Figure 5 is a third embodiment of the light guide pattern of the present invention. The fourth embodiment of the light guide pattern of the present invention

Figure 7 is a top view of a conventional backlight module; the figure shows the phenomenon of light diffusion outward. Figure 8 is a schematic diagram of the light path when the conventional backlight module is used with a brightness enhancement film. Figure 9 is a conventional Top view of a backlight module with an arc-shaped light guide pattern. The figure also shows the form of the angle between the light and the light-guide pattern. Figure 10 shows the light path when a conventional backlight module with an arc-shaped light guide pattern is used. Schematic diagram 11 is a top view of a conventional backlight module with an arc-shaped light guide pattern and a brightness enhancement film

[Illustration of figure number] Light guide pattern 7 2 Brightening film 8 Light guide plate 9 1 (conventional part Light guide plate 7 1 Light source 7 3 Condensing pattern 8 1

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Claims (1)

557374 VI. Scope of patent application1. A backlight, a reflection of the guide pattern 'and an arc arranged on the reverse side; the increase surface, and the light guide plate 2 · a light guide structure of a backlight module, which is guided by a The light plate is composed of a light source plate and a brightness enhancement film; the light plate is provided with a plurality of light guides on one of the top surface and the bottom surface, and each of the light guide patterns is in a concentric form with the light source as a center; One of the top surface and the bottom surface of the light guide plate 4 of which is based on Yishen, and one of them is backlit. Please direct the light guide to the light source, please use the light guide film to brighten the guide module module. The farther J Fan light plate is the brightness enhancement film on the top surface of the film. Most of the light sources for focusing are the space between the guides around the first item. In the same arrangement pattern as the reverse and bottom surfaces, the brightness enhancement film is in the pattern, and the backlight mode light patterns described in the concentric circles of the circle centers are respectively distributed in a form separated from the light source by the backlight mode light. Figure The samples are the majority and the condensing pattern on the other side. The top and bottom spotlight patterns are arranged in an arc. The light guide structure of the group has a space, and the closer the distance is, the larger the space between the light guide structure of the group and the protruding structure is according to the light guide structure of the backlight module described in the first item of the scope of the patent application. Each of the light guide patterns of the light plate is a concave structure. According to the light guide structure of the backlight module described in item 1 of the patent application scope, Page 14 557374 6. Scope of patent application Wherein, the light-concentrating pattern of the brightness enhancement film is a convex structure with a V-shaped cross section. 7. The light guide structure of the backlight module according to item 1 of the scope of the patent application, wherein each of the light guide patterns of the light guide plate is a V-shaped structure. 8. The light guide structure of the backlight module according to item 1 of the scope of the patent application, wherein each of the light guide patterns of the light guide plate is in the shape of an arc-shaped cross section. 9. The light guide structure of the backlight module according to item 1 of the scope of the patent application, wherein the light source is disposed near a corner of the light guide plate. 10 · The light guide structure of the backlight module according to item 1 of the scope of patent application, wherein the light source is disposed at a corner of the light guide plate. 1 1 · The brightness enhancement film of the backlight module according to item 2 of the scope of the patent application, wherein the light-concentrating patterns have a space therebetween, and the space between the light-guiding patterns is spaced closer to the light source. The larger, the farther away from the light source, the smaller the morphological distribution. 1 2 · The brightness enhancement film of the backlight module according to item 2 of the scope of the patent application, wherein the light-concentrating pattern is a convex structure with a V-shaped cross-section. Page 15