TWI418864B - Light-guide apparatus with micro-structure, and a backlight module and an lcd device having the same - Google Patents

Description

Light guide device with microstructure and backlight module and liquid crystal display having the same

The invention relates to a light guiding device with a microstructure, in particular to a light guiding device with a microstructure formed by a co-extrusion process and having reflection, homogenizing and light guiding functions, which can be matched with one side light source. A backlight module that is used to form a display.

The Light Guide Plate is a light guiding medium in the backlight module of the display. The majority of the backlight modules are Edge Type. The light guided by the light guide plate is emitted from the front of the display. Improve panel brightness and control brightness evenly.

The principle of the light guide plate is to use light to enter the light guide plate to generate light reflection, and to transmit the light to the other end of the light guide plate. In particular, a specific structure of one side of the light guide plate can be used to generate a diffusion phenomenon at various angles, and the reflected light is guided to the light guide plate. On the front side, the larger the refractive index, the better the light guiding ability. In addition, in addition to the light that is directed toward the front side, some of the light is again introduced into the light guide plate by the reflector at the bottom of the light guide plate.

As shown in FIG. 1, a light source module of a light-emitting element disclosed in the prior art, such as U.S. Patent No. 7,108,385 (issued on September 19, 2006), discloses a light guide. The liquid crystal panel 57, the diffusion film 56, the prism module 55, the light source module 50, and the light-emitting plane 523 include a light guide plate 520 and a reflector 524, and the circuit board 51 and the light-reflecting layer 54 of the light source module 50, Each component forms a backlight module 5.

However, the shortcomings of various components in the conventional light guide plate, including the reflective sheet, the light guide plate, the diffusion sheet, the diamond lens, etc., can be summarized as follows:

As shown in FIG. 2, the light guide plate 520 of the prior art faces the problem of optical loss during light transmission. In order to increase the effect of reflecting light in the backlight module 5, a reflective plate 524 is added in the prior art. Since there is an air layer 525 between the reflective plate 524 and the light guide plate 520, the loss of the light 581 is increased by 8%. Left and right, reducing light utilization, and will increase the backlight module 5 process and cost.

In addition, if the light guide plate of the prior art adopts the technology of printing the light guide plate, it is easy for the printed light guide plate to pass through the screen, the ink, and the screen printing technology, resulting in poor control of the product yield and lack of the bright band. As shown in FIG. 3, it is a bright band diagram of the light guide plate 520 of the prior art; on the light exit surface of the light guide plate 520, a strip-shaped brightest area 582 (ie, a bright line) appears in the central portion thereof due to uneven light emission. ), the second bright area 583, and the outermost dark area 584.

As described above, the conventional technology increases the optical loss due to the air layer between the light guide plate and the plate, the cost of the backlight module is high, the bright line phenomenon is obvious, the processing of the prism module is not easy, and the microstructure is easily damaged. There is room for further improvement.

The main object of the present invention is to provide a light guide device having a microstructure and a backlight module and a liquid crystal display having the light guide device, wherein the light guide device is a simple three-layer composite structure of a co-extrusion process. The utility model has the advantages of improving the utilization ratio of the light, more uniform light emission, brightening the brightness, reducing the cost of the backlight module, and eliminating the need for a prism module.

To achieve the above objective, the present invention discloses a light guide device having a microstructure, which can be used with a side light source to form a backlight module of a display. The light guiding device comprises at least: a light homogenizing layer, a light guiding layer and a reflective layer. The light guiding layer defines a light incident surface, and the light incident surface is such that one of the light emitted by the side light source enters the light guiding layer from the light incident surface. The reflective layer can reflect the light from the light guiding layer that is directed toward the reflective layer back to the light guiding layer. The surface of the uniform light layer farther from the side of the reflective layer is a light exiting surface, and the light guiding layer is located between the reflective layer and the light homogenizing layer. The light-emitting surface is perpendicular to the light-incident surface, and at least a portion of the light in the light-guiding layer can be emitted from the light-emitting surface. Wherein, the reflective layer, the light guiding layer and the homogenous light layer are integrally formed by co-extrusion, and there is no air interface between the reflective layer and the light guiding layer; and between the light guiding layer and the reflective layer A reflective surface is defined, and a stereoscopic microstructure is disposed on the reflective surface.

In a preferred embodiment, the aspect ratio data structure of the reflective surface conforms to the following relationship: And n1 <n2; wherein H2 is the depth of the microstructure of the reflective surface, P2 is the width of the microstructure of the reflective surface, n1 is the refractive index of the light homogenizing layer, and n2 is the refractive index of the light guiding layer rate.

In a preferred embodiment, the microstructured light guiding device is more in accordance with at least one of the following conditions: 0.233 ≦ (H2 / P2) ≦ 0.419; P2 value is between 80 μm and 250 μm; The ratio of (H2/P2) is between 0.2 and 0.319, and the ratio of the thickness of the uniform layer t1 to the thickness t2 of the light guiding layer is 1≦t1/t2≦29; the microstructure of the reflecting surface is discontinuous. Microstructure, and the G value between two adjacent microstructures is between 0 and 1.4 mm.

In a preferred embodiment, the microstructured light guiding device further includes at least one of the following: a plurality of diffusion particles added to the light guiding layer; a plurality of diffusion particles added to the light homogenizing layer; The illuminating surface is provided with a stereoscopic microstructure; two plastics of different refractive indices are mixed in the reflective layer; a plurality of reflective particles are added to the reflective layer; and one of the rough surfaces or one of the controllable changes is controlled. A matte surface is formed on the illuminating surface.

In order to more clearly describe the light guide device having the microstructure and the backlight module and the liquid crystal display provided by the present invention, the following will be described in detail with reference to the drawings.

(a) Overview of the device of the invention (three-layer structure):

As shown in FIG. 4, the micro-structured light guiding device 1 of the present invention, in particular, refers to an ALL IN ONE light guiding device, which is integrated and integrated by a co-extrusion integrated process, in the light guiding device. The three-dimensional microstructure is formed on the reflective surface between the light guiding layer and the reflective layer, so that a single light guiding device can achieve the effects of uniform light, light guiding and light reflection, and can be applied to any large panel in the form of a side light source 2, The body of the light guiding device 1 mainly comprises: a microstructured reflective layer 11; a light guiding layer 12; and a microstructured light homogenizing layer 13.

As shown in FIG. 4, it is one of the embodiments of the light guiding device 1 having a microstructure according to the present invention. The micro-structured light guiding device 1 is a simple one-piece three-layer composite material (for a co-extrusion process) microstructure light guiding device.

(b) Overview of the microstructured reflective layer 11 (lower layer) of the present invention:

One of several important concepts of the microstructured light guiding device 1 of the present invention is to utilize the design of the reflective surface microstructure to cause reflection of light generated by the side light source 2 in the light guiding device 1. The light source is dispersed in place of the conventional dot pattern; and the microstructure is formed on the reflective surface between the reflective layer 11 and the light guiding layer 12, thereby replacing the use of the reflecting plate. Wherein, the diffused particles of the microstructured light-homogenizing layer 13 form a surface light source or a point light source to form a surface light source, and the microstructures of the light-homogenizing layer 13 and the reflective layer 11 correspond to each other, thereby replacing the use of the reflective sheet to achieve reflection and light guiding. And the effect of uniform light.

By the above technique, the present invention reduces the optical loss caused by the reflective sheet, and the main mode is the reflective sheet or the reflective layer 11 formed simultaneously with the light guiding layer 12. As shown in FIG. 5, the micro-structured light guiding device 1 of the present invention is formed by adding a microstructure and a reflective layer 11 on the bottom side of one of the light guiding layers 12, and simultaneously forming the light guiding device 1 so that the microstructure is There is no air interface layer between the reflective layer 11 and the light guiding layer 12 in the body of the light guiding device 1. Since there is no air layer between the reflective layer 11 and the light guide layer 12 of the present invention, the micro-structured light guiding device 1 of the present invention can enhance light utilization as compared with the conventional technique of air separation shown in FIG. The microstructure can also be used as a reflection and light diffusion phenomenon of the light guiding layer, and at the same time achieve the effect of reflection and light guiding, and can effectively reduce the optical loss to below 4%. At the same time, since the manufacturing process of the micro-structured light guiding device 1 of the present invention is simplified, the film guiding procedure of the light guiding device, the backlight module manufacturing process and the cost can be reduced.

The preferred embodiment of the reflective layer 11 of the microstructured light guiding device 1 of the present invention is:

(1) The reflective layer 11 of the present invention is produced by mixing two kinds of plastics having different refractive indexes or adding a small amount of reflective particles to the reflective layer plastic.

(2) When the reflective layer 11 is formed by mixing two kinds of plastics having different refractive indexes, the mixing ratio of the different refractive index plastics is 7:3.

(3) When the reflective layer 11 is formed by adding the reflective particles 111, the refractive index of the reflective particles 111 is 2.2 to 3.2, and the added concentration is less than 0.5% by weight.

(4) The reflective particle diameter 111 is in the range of 1-100 μm, and the optimum range is 4-50 μm.

(5) The refractive index of the plastic of the reflective layer 11 itself is between 1.6 and 2.5.

(6) The refractive index difference between the reflective layer 11 and the light guiding layer 12 is between 0.05 and 1.

(III) Overview of the microstructured light homogenizing layer 13 (upper layer) of the present invention:

In the embodiment of the micro-structured light guiding device 1 of the present invention, the plurality of micro-diffusion particles 131 added in the microstructure homo-light layer 13 are used to form a surface light source or a point source to form a surface light source to achieve uniform light and concealing. The effect is to increase the light utilization efficiency by the difference in refractive index.

A preferred embodiment of the microstructured light-receiving layer 13 of the microstructured light guiding device 1 of the present invention may be:

(1) A small amount of the diffusion particles 131 is added to the light homogenizing layer 13, or the surface of the light-emitting surface 132 of the light-homogenizing layer 13 is atomized.

(2) The difference in refractive index between the diffusion particles 131 and the plastic substrate of the light-homogenizing layer 13 is 0.04 < Δn < 0.1.

(3) The particle size of the diffusion particles 131 is between 2 μm and 10 μm.

(4) The roughness (Ra) of the upper surface (light-emitting surface 132) of the uniform light layer 13 is 1 μm<Ra<6 μm, which can improve the luminance and uniformity.

(5) The refractive index of the plastic substrate of the homogenous layer 13 itself is between 1.42-1.63.

(d) The microstructure of the present invention:

In the embodiment of the microstructured light guiding device 1 of the present invention, the surface adjacent to the light guiding layer 12 and the reflective layer 11 (that is, the bottom side of the light guiding layer 12 or the top side of the reflective layer 11) ) is defined as a reflective surface. The present invention adds a plurality of microstructures to the reflective surface and/or the upper surface of the uniform light layer 13 (light exit surface 132). In the present invention, the distance between each microstructure is an equal distance, a non-equidistant distance, or a staggered microstructure. Each of the microstructures may be a three-dimensional (eg, pyramid) structure having asymmetrical or symmetrical triangles, laterally asymmetrical or symmetrical triangular structures, columnar structures, curved structures, and the like. Preferably, for example, the aspect ratio of each of the microstructures of the reflecting surface and/or the light-emitting surface is 0.02 to 0.8; and it is preferable that the width of each of the microstructures is between 80 μm and 250 μm.

The relationship between the thickness of the reflective layer (Rh) and the microstructure depth (H2) of the reflective surface is 0.02 < Rh (1/H2) < 0.8, and therefore, both reflection and light guiding effects are obtained.

(5) The relationship between the light guiding effect and the thickness of the microstructure reflective layer 11 (lower layer) of the present invention:

In the embodiment of the micro-structured light guiding device 1 of the present invention, the relationship between the microstructure thickness of the reflective layer 11 and the amount of light incident can obtain a preferred range, that is, the thickness of the reflective layer 11 should not be greater than the total thickness of the body. (1/10 of the thickness of the three layers of the light-homogenizing layer 13 and the light-guiding layer 12 and the reflective layer 11).

(6) The relationship between the thickness (lower layer) of the microstructure reflective layer of the present invention and the microstructure depth:

Please refer to FIG. 6 , which is a graph of luminance relationship of the light guiding device with microstructure according to the present invention. The two-axis relationship data in this graph is as follows, wherein the vertical axis reflects the luminance formed by the overall microstructure (Luminance), that is, the luminance value measured on the light-emitting surface, and the horizontal axis represents the thickness of the reflective layer (Rh). The thickness-depth relationship of the microstructure of the reflective layer multiplied by the inverse depth of the microstructure of the reflective surface (1/H2).

Therefore, according to the data of FIG. 6, different thicknesses of the reflective layer and the microstructure depth have different effects on the luminance of the light-emitting surface. When the value of Rh(1/H2) falls within the range of 0.02<Rh(1/H2)<0.8, the reflection and light guiding effects can be simultaneously achieved. The reflectivity of the reflective layer is about 80%. If it exceeds this range, the reflection will be made. The rate is too low or the uniformity is not good; and, when the Rh(1/H2) value further falls within the optimal range of 0.02<Rh(1/H2)<0.5, the microstructured light guide of the present invention The device can further provide a higher luminance on the illuminating surface, that is, an optical representation with better reflection and uniformity.

(7) The relationship between the thickness, concentration and uniformity of the homogenous layer 13 of the present invention:

In the embodiment of the microstructured light guiding device 1 of the present invention, the embodiment of the relationship between the thickness, concentration and uniformity of the light-homogenizing layer 13 and the light guiding layer 12 can be as follows:

(1) The light guiding layer 12 is added with a small amount of diffusing particles, which can solve the phenomenon of bright band and poor uniformity.

(2) The smaller the particle size of the diffusion particles, the narrower the same penetration distribution.

(3) The larger the particle size of the diffusion particles, the wider the same penetration distribution.

(4) varies with the difference in refractive index and the desired added concentration; varies with the particle size and the desired added concentration.

The micro-structured light guiding device 1 of the present invention can solve the problem of poor brightness and uniformity by adding a small amount of diffusing particles in the light guiding layer 12, and can also improve the utilization of light; when diffusing particles and guides When the refractive index difference of the optical layer 12 plastic substrate is in the range of 0.04 < Δn < 0.1, the state of high transmittance can be maintained. Moreover, the particle size of the diffusion particles in the light guiding layer 12 is between 2 μm and 10 μm, and the refractive index of the plastic substrate of the light guiding layer 12 itself is between 1.4 and 2.63.

The thickness ratio of the light-homogenizing layer 13 and the light guiding layer 12 of the present invention, the concentration of the light-homogenizing layer 13 and the diffusing particles, and the brightness and the light uniformity are related.

The roughness factors affecting the shape of the light guiding layer 12 and the smoothing layer 13 in the light guiding device 1 having microstructures of the present invention are as follows:

(1) When the surface (light-emitting surface 132) of the light-homogenizing layer 13 is uneven (that is, when it has roughness), it helps to increase the luminance value of the light guide plate.

(2) The roughness of the surface (light-emitting surface 132) of the light-homogenizing layer 13 varies depending on the microstructure of the reflecting surface of the reflective layer 11.

Roughness (Ra) of the surface of the uniform layer 13 (light-emitting surface 132) Advantages: (1) increase the brightness of the light guide plate; (2) solve the problem of bright band; (3) improve the uniformity.

Therefore, in the relationship between the roughness (Ra) and the luminance (L) of the light-emitting surface 132 of the light-homogenizing layer 13, the roughness is preferably from 1 μm to 6 μm.

(VIII) Other various embodiments of the specific structure of the body of the micro-structured light guiding device of the present invention:

In the light guide device 1 having a microstructure in the present invention, the diffusion layer 131 may or may not be added to the uniform layer 13, and the upper surface (light-emitting surface 132) of the uniform layer 13 may be a mirror surface or a matte surface. Planar, continuous microstructure, discontinuous microstructure of one-side light-in design, and discontinuous microstructure of double-sided light-input design; at the same time, light guide layer 12 may or may not be added Diffusion particles 122; at the same time, the contact surface of the reflective layer 11 and the light guiding layer 12 (reflecting surface 112) may also be a mirror plane, a matte plane, a discontinuous microstructure with a continuous microstructure, and a single-side light-in design. And the discontinuous microstructure of the double-sided light design and other aspects. Therefore, after the reflective layer 11 and the light guiding layer 12 of the various designs described above are cross-matched with the light-homogenizing layer 13, the body of the light guiding device 1 having the microstructure in the present invention as shown in FIG. 7 can be obtained. Various embodiments of the structure of the reflective layer 11, the light guiding layer 12 and the light homogenizing layer 13. For example, the four structural diagrams 411, 412, 413, and 414 sequentially from top to bottom in the column 41 of FIG. 7 respectively show that there are diffusion particles (Fig. 411, 412) and no in the uniform light layer. The upper surface of the homogenizing layer (the light-emitting surfaces 4111, 4121, 4131, and 4141) having the diffusion particles (Figs. 413, 414) but four (Figs. 411, 412, 413, 414) has a continuous structural design and a reflective layer. The contact surface (reflection surface 4112, 4122, 4132, 4142) with the light guiding layer is a four embodiment of a plane (mirror surface or matte surface) (wherein the light guiding layer of the embodiment of FIGS. 411 and 413 has diffusion particles, However, the embodiments of Figures 412 and 414 are not. For another example, the four structural diagrams 421, 422, 423, and 424 in the field 42 respectively show diffusion particles (Fig. 421, 422) and no diffusion particles (Figs. 423, 424) in the uniform light layer, but four The upper surface of the light layer (light-emitting surfaces 4211, 4221, 4231, 4241) is a plane (mirror or matte surface) and the contact surfaces of the reflective layer and the light guiding layer (reflecting surfaces 4212, 4222, 4232, 4242) are Four embodiments having a discontinuous microstructure with a double-sided light-in design (wherein the light-guiding layers of the embodiments of Figures 421 and 423 have diffusing particles, but the embodiments of Figures 422 and 424 are not); other embodiments analogy. In addition, in various embodiments in which both the light-emitting surface and the reflective surface have a microstructure (whether continuous, discontinuous, single-sided or dual-input light design), the arrangement of microstructures on the light-emitting surface The direction of arrangement of the microstructures and the microstructures disposed on the reflective surface may be mutually parallel or orthogonal.

The light guiding device 1 with microstructure of the present invention can be versatilely matched and designed in addition to the structure of the light emitting surface and the reflecting surface, and the specific structural design of the microstructure disposed on the light emitting surface or (and the reflecting surface) is also many. Different embodiments, such as but not limited to the embodiments shown in Figures 8A through 80, are illustrated one by one.

As shown in FIG. 8A, in the first embodiment of the microstructure on the microstructured light guiding device 1 of the present invention, the microstructures disposed on the light emitting surface or (and the reflecting surface) may have a plurality of narrow and parallel arrays. Continuous triangular strip microstructure 801.

As shown in FIG. 8B, in the second embodiment of the microstructure on the microstructured light guiding device 1 of the present invention, the microstructures disposed on the light emitting surface or (and the reflecting surface) may have a plurality of narrow and parallel arrays. A continuous semi-circular strip microstructure 802.

As shown in FIG. 8C, in the third embodiment of the microstructure on the microstructured light guiding device 1 of the present invention, the microstructure disposed on the light emitting surface or (and the reflecting surface) may have a plurality of three-dimensional arrays arranged in an array. The continuous cone (pyramid) microstructure 803.

As shown in FIG. 8D, in the fourth embodiment of the microstructure of the micro-structured light guiding device 1 of the present invention, the microstructure disposed on the light-emitting surface or (and the reflective surface) may have a plurality of three-dimensional arrays arranged in an array. The continuous spherical microstructure 804.

As shown in FIG. 8E, in the fifth embodiment of the microstructure on the microstructured light guiding device 1 of the present invention, the microstructure disposed on the light emitting surface or (and the reflecting surface) may have a plurality of three-dimensional arrays arranged in an array. A continuous arcuate tapered microstructure 805.

As shown in FIG. 8F, in the sixth embodiment of the microstructure on the microstructured light guiding device 1 of the present invention, the microstructures disposed on the light emitting surface or (and the reflecting surface) may have a plurality of narrow and parallel arrays. Non-continuous three-dimensional triangular strips, unequal distances and two sides of the microstructure 806 which are densely controlled and densely spaced away from the light entrance surface (especially suitable for double-sided light entering, that is, the left and right sides of the light guiding layer are Design into the glossy surface).

As shown in FIG. 8G, in the seventh embodiment of the microstructure on the microstructured light guiding device 1 of the present invention, the microstructures disposed on the light emitting surface or (and the reflecting surface) may have a plurality of narrow and parallel arrays. A discontinuous three-dimensional triangular strip-shaped, equidistant and densely varying microstructure 807.

As shown in FIG. 8H, in the eighth embodiment of the microstructure of the micro-structured light guiding device 1 of the present invention, the microstructures disposed on the light-emitting surface or (and) the reflecting surface may have a plurality of narrow and parallel arrays. Non-continuous three-dimensional semi-circular strips, unequal distances and two sides of the microstructure 808 which are densely controlled and densely spaced away from the entrance surface (especially suitable for double-sided light entering, that is, the left and right sides of the light guiding layer are Design into the glossy surface).

As shown in FIG. 8I, in the ninth embodiment of the microstructure of the micro-structured light guiding device 1 of the present invention, the microstructures disposed on the light-emitting surface or (and the reflecting surface) may have a plurality of narrow and parallel arrays. A discontinuous three-dimensional semi-circular strip, isometrically densely varying microstructure 809.

As shown in FIG. 8J, in the tenth embodiment of the microstructure on the microstructured light guiding device 1 of the present invention, the microstructures disposed on the light emitting surface or (and the reflecting surface) may have a plurality of arrays arranged in a non-arrangement. A continuous three-dimensional cone (pyramid), a structure 810 that is unequally spaced and that is densely spaced from the light entrance surface to control the density and density (especially suitable for double-sided light entering the left and right sides of the light guiding layer) All are designed for the entrance surface).

As shown in FIG. 8K, in the eleventh embodiment of the microstructure on the microstructured light guiding device 1, the microstructure disposed on the light emitting surface or (and the reflecting surface) may have a plurality of elongated and arrays. Arranged discontinuous three-dimensional cones (pyramids), isometrically densely varying microstructures 811.

As shown in FIG. 8L, in the twelfth embodiment of the microstructure on the microstructured light guiding device 1 of the present invention, the microstructures disposed on the light emitting surface or (and the reflecting surface) may have a plurality of arrays arranged in an array. A discontinuous three-dimensional spherical microstructure, a microstructure 812 that is unequally spaced and that is densely spaced away from the entrance surface, and is particularly suitable for bilateral light entrance, that is, both sides of the light guide layer Designed for the light surface).

As shown in FIG. 8M, in the thirteenth embodiment of the microstructure of the microstructured light guiding device 1 of the present invention, the microstructures disposed on the light emitting surface or (and the reflecting surface) may have a plurality of arrays arranged in an array. A discontinuous three-dimensional spherical microstructure, an isometric densely varying microstructure 813.

As shown in FIG. 8N, in the fourteenth embodiment of the microstructure of the microstructured light guiding device 1, the microstructure disposed on the light emitting surface or (and the reflecting surface) may have a plurality of arrays arranged in an array. A discontinuous arc-shaped pyramidal microstructure, a microstructure 814 that is unequally spaced and densely spaced away from the entrance surface, and is particularly suitable for bilateral light entrance, that is, the left and right sides of the light guide layer All are designed for the entrance surface).

As shown in FIG. 80, in the fifteenth embodiment of the microstructure of the microstructured light guiding device 1, the microstructure disposed on the light emitting surface or (and the reflecting surface) may have a plurality of arrays arranged in an array. A discontinuous arcuate pyramidal microstructure, a microstructure 815 of varying isometric density.

Please refer to FIG. 9 , which is a schematic diagram of another embodiment of a light guide device 1 a having a microstructure according to the present invention. In this embodiment, the upper surface of the light homogenizing layer 13a of the microstructured light guiding device 1a is also on the light emitting surface 132a, and on the reflecting surface 112a between the reflective layer 11a and the light guiding layer 12a. Features a microstructure. The microstructures disposed on the light-emitting surface 132a and the reflective surface 112a are both discontinuous; and the microstructures disposed on the reflective surface 112a are not only discontinuous but also densely varying microstructures. Moreover, for the discontinuous and densely varying reflective surface 112a microstructure, the distance G between two adjacent microstructures on the reflective surface 112a closest to the light entrance surface 15 is the largest, and the farther away from the light. The microstructure pitch G on the reflecting surface 112a at the surface 15 is gradually smaller. By providing a microstructure on the reflecting surface 112a that can control the density variation, that is, the smaller the distance (the denser) the distance G is, the farther the light is, the smaller the light is, and the brighter the light entering the light surface 15 is. The darker the phenomenon away from the light entrance surface 15. Moreover, when the structural pitch G value of the discontinuous microstructure disposed on the reflective surface 112a is in the range of 0 to 1.4 mm, the at least one optical film 590 attached to the light emitting surface 132a is further used. , the light-emitting surface 132a will not have a bright line phenomenon (the bright line is not visible). Similarly, if a microstructure similar to the above-described discontinuity and capable of controlling the density change is provided on the light-emitting surface 132a, a similar light-emitting uniform effect can be achieved.

By attaching the at least one optical film 590 to the light-emitting surface 132a of the micro-structured light guiding device 1a of the present invention, and providing the side light source 2 at the light-incident surface 15, and then combining with other conventional accessory accessories, A backlight module can be constructed. Thereafter, the backlight module can be combined with a conventional liquid crystal panel 57 to form a liquid crystal display.

Please refer to FIG. 10 and FIG. 11 respectively, which are respectively a flow chart and a schematic diagram of an embodiment of a co-extrusion process for fabricating a light guide device having a microstructure. For example, in the co-extrusion process of the light guiding device 1a of the present invention having an integrally formed three-layer structure as shown in FIG. 9, the plastic containing the reflective particles 111a for forming the reflective layer 11a is first placed on the extrusion machine side. The extruder 1 is in the barrel 21, and the plastics containing the different particle size and different refractive index diffusion particles 122a for forming the light guiding layer 12a are placed in the main extrusion drum 22 of the extrusion machine, and are used to form The plastic containing the different particle size and different refractive index diffusion particles 131a of the homogenous light layer 13a is placed in the barrel 23 of the extrusion machine sub-extrusion machine 2. The plastic used for the light guiding layer 12a and the light absorbing layer 13a and the diffusion particles 122a and 131a may be the same but may be different materials. Next, the plastics in the tanks 21, 22, and 23 are respectively kneaded by the screw 24, and then enter the main and sub-layers of the extrusion die (T Die) 25. Thereafter, the three sets of rollers, R1, R2, and R3, are combined to form a light guide device 1a having the function of "all in one" and having a reflection, light guiding, and leveling function. Compared with the prior art, there is a conventional technique in which a reflective layer is plated on the lower surface of the light guiding layer by a coating method, and the technique of co-integration molding of the present invention has more convenience and progress in the process.

Please refer to FIG. 12, which is a schematic view of a sandblasting process for forming a rough surface on a light-emitting surface of a light guide device having a microstructure. In the present invention, the rough surface or the matte surface formed on the light-emitting surface of the light guide device having a microstructure, that is, the rough surface or the matte surface formed on the upper surface of the light guiding layer, the degree of roughness can be controlled by The blasting pressure p of the blasting device 31, the blasting speed v, and the distance d between the nozzle 32 and the roller surface 33 are controlled. Then, the roller surface 33 having a predetermined rough surface is used as the roller R1, R2, and R3 shown in FIG. 11 to roll the plastic sheet in the co-extruding process, and then the three layers are integrally formed in the present invention. The reflective surface and/or the light-emitting surface of the light guiding device of the structure is extruded with a rough surface. The roughness of the rough surface will affect the degree of electrostatic adsorption between the light-emitting surface of the microstructured light guiding device and the optical film of the present invention, and the uniformity of the light guiding ability, as shown in the following Table 2:

In Table 2, when the roughness Ra of the rough surface formed on the light-emitting surface of the micro-light guiding device of the present invention is less than 0.46 μm, the light-emitting surface and the optical film of the micro-structured light guiding device are easily obtained. The electrostatic adsorption between the sheets becomes severe and it is easy to scratch them. When Ra is greater than 2.21 μm, the light extraction efficiency is increased, and the light uniformity of the light guide device having a microstructure is lowered, and when the Ra is greater than 6 μm, the light output quality may not pass through the quality control. Therefore, in the present invention, the roughness of the rough surface formed on the light-emitting surface of the light guide device having a microstructure can be controlled to be between 0.07 μm and 2.52 μm, preferably between 0.46 μm and 2.21 μm. And preferably between 1 μm and 2.21 μm.

In the present invention, the plastics of the light guiding layer and the reflective layer can be selected from the conventional plastics, such as, but not limited to, polymethylmethacrylate (PMMA), polycarbonate (PC), and poly. Polyethylene terephthalate (PET), MS, and the like. The diffusion particles added to the light guiding layer may also be selected from currently known materials such as, but not limited to, PMMA particles, PC particles, PET particles, MS particles, and the like. The reflective particles may also be selected from currently known materials such as, but not limited to, SiO ₂ particles, TiO ₂ particles, and the like.

For the micro-structured light guiding device of the present invention, in addition to the co-extrusion integral molding and microstructure design, the light utilization efficiency and the optical loss can be improved as described above, and no additional reflective sheet and brightness enhancement film are needed. In addition to the advantages of (BEF), simplifying the module architecture, reducing the cost of the backlight module, and reducing the electrostatic adsorption of the optical film, the optical performance of the light guide (such as light uniformity, brightness, taste, etc.) The promotion is also an important consideration.

Please refer to FIG. 13A and FIG. 13B respectively, which are respectively an embodiment of the light guiding device of the present invention and a corresponding graph between the angle of the light pattern and the brightness of the light emitting surface; the X axis of the graph The light-emitting angle value of the light-emitting surface is in the range of 0 to 90 degrees, and the Y-axis is the lightness value. Taking the structure of the light guiding device 1b of the present invention shown in FIG. 13A as an example, the body of the light guiding device 1b is a three-layer flat plate-like structure integrally formed by co-embossing, and includes a uniform light layer 13b located in the upper layer. The light guiding layer 12b located in the intermediate layer and the reflective layer 11b located in the lower layer and added with reflective particles. A light incident surface 15 is disposed on a side of the light guiding layer 12b of the body of the light guiding device 1b, and a side light source 2 (which may be a CCFL or LED) is disposed adjacent to the light incident surface 15 for generating a light 20, the light 20 The light incident surface 15 is incident on the light guiding layer 12b of the light guiding device 1b. The surface adjacent to the light guiding layer 12b and the reflective layer 11b (that is, the bottom surface of the light guiding layer 12b or the top surface of the reflective layer 11b) is a reflecting surface 112b, and the light equalizing layer 13b is farther away from the reflective layer 11b. The side surface (that is, the top surface of the light homogenizing layer 13b) is a light exiting surface 132b. The diffusion layer may or may not be added to the light guiding layer and the light homogenizing layer; and when the materials of the plastic material (including the diffusion particles added therein) of the light guiding layer and the light homogenizing layer are the same, then the guiding The optical device 1b substantially corresponds to a two-layer structure in which only the co-extrusion of the light guiding layer and the reflective layer is integrally formed. The embodiment of the light guiding device 1b of the present invention shown in FIG. 13A is exemplified by the same material of the plastic material (including the diffusion particles added therein) of both the light guiding layer and the light homogenizing layer. In this embodiment, the light incident surface 15 and the light exit surface 121b are perpendicular to each other. A normal line N perpendicular to the light-emitting surface 121b may be defined at any point of the light-emitting surface 121b. Due to the characteristics of the reflective layer 11b, when the light 20 deflected downward inside the light guiding layer 12b is directed toward the reflecting surface 112b, the light 20 will be reflected by the microstructured reflecting surface 112b and folded back to the light guiding layer. 12b and change the angle. However, when the light 20 traveling inside the light guiding layer 12b is incident on the light emitting surface 132b, there is a reflection due to the difference in the angle between the traveling direction of the light 20 and the normal N of the light emitting surface 132b. 201 or light 202 have two different optical effects. As for one of the factors determining whether the light 20 will reflect or emit light at the light exiting surface, it is determined by the critical angle θc of the light refraction between the refractive index n of the light guiding layer and the homogenizing layer itself and the outside air. Among them, the critical angle θc = sin ^-1 (1/n).

In the present embodiment, taking the refractive index n=1.58 of the light guiding layer (the homogenous light layer) as an example, and substituting n=1.58 into the above formula, the critical angle θc=39.26° (about 40°) can be calculated. In another embodiment, if the refractive index n=1.49 of the light guiding layer (the homogenous light layer) is taken as an example, the critical angle θc=42.16° (about equal to 42°) can be calculated. When the angle θ between the light 20 incident on the light-emitting surface 132b and the normal N is smaller than the critical angle θc, the light 20 will illuminate the light 202 and refract out from the light-emitting surface 132b; and when the angle θ is greater than the critical angle At θc, the light 20 will be reflected 201 back into the light guiding layer 12b.

According to the structure of an embodiment of the light guiding device 1b of the present invention shown in FIG. 13A, a corresponding graph between the angle of the light pattern of the light exiting surface and the brightness of the light can be tested and plotted. As shown in Figure 13B, the two-layer structure (that is, only the light guide layer and the reflective layer, or when the light-homogenizing layer and the light-guiding layer plastic material are the same) and the three-layer structure (with different plastic materials) That is, two kinds of light guiding devices, which are composed of a uniform refractive index, a light guiding layer and a reflecting layer, are used to test and draw a corresponding graph between the angle of the light pattern of the light emitting surface and the brightness of the light. It can be seen from the graph shown in FIG. 13B that the curve of the embodiment of the light guiding device with double-layer structure and no special uniform light design is obviously shifted to the right side of the vertical normal line with the light-emitting angle of 0 degree, which is shown in the lack of different refractive index. In the case of the uniform light layer, the light emitted by the light-emitting surface has a maximum brightness in a range of oblique viewing angles of about 30 to 50 degrees; in contrast, a 0 degree angle of view suitable for human eyes is relatively low in brightness. However, for a three-layered light guiding device embodiment having a suitable reflective surface microstructure aspect ratio and a suitable ratio of refractive index to thickness of the homogenous light layer and the light guiding layer, it is emitted by the light exiting surface. The light is obviously directed to the positive viewing angle, so that the light-emitting surface has the maximum brightness in the range of angles of positive and negative 20 degrees, thereby increasing the brightness of the backlight module.

According to the foregoing optical performance evaluation method, a plurality of reflective surfaces having different width-to-depth ratio microstructures, different refractive index and refractive index of the light guiding layer, and uniform light and light guiding layers having different thickness ratios are used. To perform cross-matching, and to simulate and measure the brightness of the light-emitting surface one by one according to the manners shown in FIG. 13A and FIG. 13B, and the results are summarized in Table 3 below.

For the measurement method of the brightness of the light-emitting surface light, please refer to FIG. 14 for a schematic diagram of an embodiment of the light-emitting surface of the light-emitting surface 132 of the light-measuring light guiding device 1 of the present invention. As shown in FIG. 14, a total of 13 test zones located at different positions are selected from the range of the light-emitting surface 132 displayed in the upper view direction. The light is emitted into the light guiding device by the light source 2 of the light guiding device 1 of different structure design, and the brightness of the positive viewing angle is measured after 13 test areas of the light emitting surface 132 of the light guiding device 1 are taken. The average value is added and the average value is included in Table 3 as the measured brightness.

In Table 3, the value in the "Structure Aspect Ratio" field refers to the ratio of the depth H2 to the width P2 of the microstructure on the reflecting surface of the light guiding device (that is, the upper surface of the reflecting layer); the "n1" field The value inside is the refractive index value of the homogenizing layer; the value in the "n2" field is the refractive index value of the light guiding layer; the value in the "t1" field is the thickness value of the homogenous layer; the "t2" field The value inside is the thickness value of the light guiding layer; the value in the "t1/t2" field is the ratio of the thickness of both the light-homogenizing layer and the light guiding layer; the value in the "light brightness" field is based on Figure 14. The average brightness of the 13 regions of the light-emitting surface measured by the examples shown in the examples.

The lightness measured by the examples of the serial number 11 to the serial number 64 in Table 3 is better than that of the other embodiments. When the reflection surface aspect ratio (H2/P2) is between 0.233 and 0.419 (also That is, 0.233 ≦ H2 / P2 ≦ 0.419) may have a better lightness; and the luminance of the embodiment of n1 < n2 is also better than the embodiment of n2 > n1. In addition, the brightness measured by the examples of No. 23 to No. 78 in Table 3 shows that when the reflection surface aspect ratio (H2/P2) value is between 0.2 and 0.319, the appropriate uniform layer and guide are provided. The light guiding device of the three-layer structure in which the ratio of the optical layer thickness is in the range of 1≦t1/t2≦29 can have a higher brightness than the light guiding device (the thickness of the light guiding layer 0) of the two-layer structure; and, three The light level of the light guiding device of the layer structure can even be 67% higher than that of the light guiding device of the two-layer structure (for example, compared with the light brightness values of the two embodiments of the serial number 54 and the serial number 56). As for the curve of the three-layer architecture light guiding device embodiment shown in FIG. 13B, the curve is simulated according to the three-layer structure of the No. 42 embodiment, and the brightness of the light-emitting surface can be as high as 5755 nits.

Referring to Figures 15A, 15B and 15C, respectively, different embodiments of the reflection surface aspect ratio (H2/P2) for light reflection in the light guiding device of the present invention are illustrated.

As shown in FIG. 15A, when the depth-to-width ratio H2/P2 of the reflecting surface 112c is too small, the light ray 20c is reflected by the microstructure of the reflecting surface 112c of the reflective layer 11c, and the light is deflected toward the large viewing angle, which deviates from the positive viewing angle. The brightness of the light measured by the light-emitting surface 132c is low, so the range of H2/P2 is preferably not less than or equal to 0.134, that is, the following mathematical formula should be met:

As shown in FIG. 15B, since when the refractive index of the uniform light layer 13d is smaller than the refractive index of the light guiding layer 12d (n1 < n2), for example, when n1=1.49 and n2=1.58, there will be a result of the following formula:

As a result, after the light is guided through the reflective layer 11d, the light can be directly emitted to the light-emitting surface 132d and emitted, and no total reflection occurs in the interface between the light-homogenizing layer 13d and the light-guiding layer 12d, so that the light is transmitted again in the light guiding layer 12d. The light energy is lost, so that the brightness of the light exit surface 132d can be obtained.

As shown in FIG. 15C, when the depth-to-width ratio H2/P2 of the reflecting surface 112e is too large, the light ray 20e is reflected by the reflecting surface 112e of the reflecting layer 11e, and the light 20e is deflected toward the light-emitting surface 15 side. Fold, deviate from the positive viewing angle, so that the brightness is low, so the range of H2 / P2 is not more than 0.5 is better, that is, should meet the following mathematical formula:

According to the above mathematical formula, it can be known that when the reflective surface microstructure of the light guiding device of the present invention conforms to the following mathematical formula, a higher light-emitting surface brightness can be obtained:

Wherein, the P2 value is preferably between 80 μm and 250 μm, and if it is less than 80 μm, the molding rate of the microstructure by the roller extrusion is reduced in the co-extrusion process, and if it is greater than 250 μm, the bright surface is easily formed on the light-emitting surface. .

The above-mentioned embodiments are not intended to limit the scope of application of the present invention, and the scope of the present invention should be based on the technical spirit defined by the content of the patent application scope of the present invention and the scope thereof. It is to be understood that the scope of the present invention is not limited by the spirit and scope of the present invention, and should be considered as a further embodiment of the present invention.

1, 1a, 1b. . . Micro-structured light guide

11, 11a, 11b, 11c, 11d, 11e. . . Reflective layer

111, 111a. . . Reflective particle

112, 112a, 112b, 112c, 112d, 112e. . . Reflective surface

12, 12a, 12b, 12c, 12d, 12e. . . Light guiding layer

122, 122a. . . Diffused particle

13, 13a, 13b, 13c, 13d, 13e. . . Uniform layer

131, 131a. . . Diffused particle

132, 132a, 132b, 132c, 132d, 132e. . . Glossy surface

15. . . Glossy surface

2. . . Side light source

20, 20c, 20d, 20e. . . Light

201, 203. . . reflection

202. . . sold out

21, 22, 23. . . Bucket

twenty four. . . Screw mixing

25. . . Extrusion die

R1, R2 and R3. . . Wheel

31. . . Sand blasting device

32. . . nozzle

33. . . Roller surface

41, 42. . . Field

411, 412, 413, 414, 421, 422, 423, 424. . . Figure

4111, 4121, 4131, 4141, 4211, 4221, 4231, 4241. . . Glossy surface

4112, 4122, 4132, 4142, 4212, 4222, 4232, 4242. . . Reflective surface

5. . . Backlight module

50. . . Light source module

51. . . Circuit board

520. . . Light board

523. . . Plane of light

524. . . Reflective plate

54. . . Reflective layer

55. . . Mirror module

56. . . Diffusion film

57. . . LCD panel

581. . . Light

582. . . Brightest area

583. . . Second bright area

584. . . Darker area

590. . . Optical film

801~815. . . microstructure

FIG. 1 is a schematic diagram of a light source module of a conventional light-emitting element.

FIG. 2 is a schematic diagram showing optical loss of a light guide plate of the prior art during light transmission.

FIG. 3 is a schematic diagram of a bright band of a light guide plate of the prior art.

4 is a schematic view of a first embodiment of a light guiding device having a microstructure according to the present invention.

FIG. 5 is a schematic view of the first embodiment of the light guiding device with microstructure according to the present invention capable of reducing light loss.

Fig. 6 is a graph showing a luminance relationship of a light guide device having a microstructure according to the present invention.

FIG. 7 is a schematic view showing various embodiments of a reflective layer, a light guiding layer and a light homogenizing layer structure in a micro-structured light guiding device according to the present invention.

8A to 8B are respectively schematic views of different embodiments of the microstructure on the light guiding device with microstructures of the present invention.

9 is a schematic view of another embodiment of a light guiding device having a microstructure according to the present invention.

Figure 10 is a flow chart showing an embodiment of a co-extrusion process for fabricating a light guide having microstructures.

Figure 11 is a schematic view showing an embodiment of a co-extruding process for fabricating a light guide having a microstructure.

Figure 12 is a schematic view of a sandblasting process for forming a rough surface on a light-emitting surface of a light guide having a microstructure.

FIG. 13A is a schematic view showing still another embodiment of the light guiding device of the present invention.

Figure 13B is a graph showing the correspondence between the angle of the light pattern of the light-emitting surface of the present invention and the brightness of the light as shown in Figure 13A.

FIG. 14 is a schematic view showing an embodiment of the brightness of the light-emitting surface of the light guiding device according to the present invention.

Figures 15A, 15B and 15C are diagrams respectively illustrating different embodiments of the reflection surface aspect ratio (H2/P2) for light reflection in the light guiding device of the present invention.

1. . . Light guiding device

11. . . Reflective layer

111. . . Reflective particle

112. . . Reflective surface

12. . . Light guiding layer

13. . . Uniform layer

131. . . Diffused particle

132. . . Glossy surface

15. . . Glossy surface

2. . . Side light source

Claims (10)

A light guiding device with a microstructure can be used with a side light source and includes: a light guiding layer defining a light incident surface; the light incident surface is provided by the side light source to emit light from the light source The surface enters the light guiding layer; a reflective layer that reflects the light that is directed toward the reflective layer back to the light guiding layer; and a light homogenizing layer that is further away from the side of the reflective layer The surface is a light emitting surface, the light guiding layer is located between the reflective layer and the light homogenizing layer, and the light emitting surface is perpendicular to the light incident surface, and at least a portion of the light in the light guiding layer is available The light-emitting surface is emitted; the reflective layer, the light-guiding layer and the light-homogenizing layer are integrally formed by co-extruding, and there is no air interface between the reflective layer and the light guiding layer; and A reflective surface is defined between the layer and the reflective layer, and a stereoscopic microstructure is disposed on the reflective surface. The light guide device with a microstructure as described in claim 1, wherein the aspect ratio data structure of the reflective surface conforms to the following relationship: And n1 <n2; wherein H2 is the depth of the microstructure of the reflective surface, P2 is the width of the microstructure of the reflective surface, n1 is the refractive index of the light homogenizing layer, and n2 is the refractive index of the light guiding layer rate. The light guiding device with microstructure as described in claim 2 is more suitable for at least one of the following conditions: 0.233 ≦ (H2/P2) ≦ 0.419; P2 value is between 80 μm and 250 μm; The aspect ratio (H2/P2) is between 0.2 and 0.319, and the ratio of the thickness of the uniform layer t1 to the thickness t2 of the light guiding layer is 1≦t1/t2≦29; the microstructure of the reflecting surface is non- The continuity of the microstructure, and the G value between two adjacent microstructures is between 0 and 1.4 mm. The light guide device having a microstructure according to the second aspect of the invention, wherein the light guide device having a microstructure further comprises at least one of the following: a plurality of diffusion particles added to the light guiding layer; a diffusion particle is added to the light homogenizing layer; a stereoscopic microstructure is disposed on the light emitting surface; two plastics of different refractive indexes are mixed in the reflective layer; and a plurality of reflective particles are added to the reflective layer; And a rough surface or a matte surface that can control the density change is formed on the light emitting surface. The light guide device with a microstructure as described in claim 4, wherein: when the plurality of diffusing particles are added to the light guiding layer, the diffusing particles in the light guiding layer and the plastic base of the light guiding layer itself The refractive index difference (Δn) value of the material is between 0.04<Δn<0.1, the particle size of the diffusion particles in the light guiding layer is between 2μm and 10μm, and the refractive index of the plastic substrate of the light guiding layer itself is 1.42. -1.63; when the plurality of diffusing particles are added to the homogenous light layer, a difference in refractive index (Δn) between the diffusing particles in the homogenous layer and the plastic substrate of the homogenous layer is 0.04 < Δn < 0.1 The particle size of the diffusion particles in the homogenous layer is between 2 μm and 10 μm, and the refractive index of the plastic substrate of the homogenous layer is between 1.42-1.63; when the reflective layer is mixed with two plastics of different refractive indices When the ratio of the two kinds of plastics with different refractive indexes is 7:3; when the plurality of reflective particles are added to the reflective layer, the refractive index of the reflective particles is 2.2 to 3.2, and the added concentration is less than 0.5% by weight. And the reflective particle has a particle diameter of 4-50 μm, and the refractive index of the reflective layer itself is 1. 6-2.5, and the refractive index difference between the reflective layer and the light guiding layer is 0.05-1; and when the rough surface is provided on the light emitting surface, the roughness (Ra) value of the light emitting surface is between 1 μm <Ra<6 μm. The light guide device with a microstructure as described in claim 4, wherein when the rough surface is provided on the light-emitting surface, the roughness (Ra) value of the light-emitting surface is between 1 μm and <Ra<2.21 μm. . The light guide device having a microstructure according to the second aspect of the invention, wherein the light-emitting surface is provided with a stereoscopic microstructure, and the arrangement direction of the microstructure on the light-emitting surface and the reflective surface The arrangement direction of the microstructures is one of either a parallel or an orthogonal arrangement direction. The light guide device having a microstructure according to claim 7, wherein the microstructure of the light-emitting surface and the microstructure of the reflective surface are one of the following: having a long narrow and parallel arrangement of continuity a triangular strip-shaped microstructure; a continuous semi-circular strip-like microstructure having a plurality of narrow and parallel arrays; a plurality of continuous tapered pyramid structures arranged in an array; and a plurality of continuous spherical microstructures arranged in an array; a plurality of continuous arcuate pyramidal microstructures arranged in an array; having a plurality of narrow and parallel arrays of discontinuous solid triangular strips, unequal distances and controllable sides that are densely spaced away from the entrance surface a densely-changed microstructure; a discontinuous three-dimensional strip-shaped, equidistantly densely-structured microstructure having a plurality of narrow and parallel arrangements; a discontinuous three-dimensional strip having a plurality of narrow and parallel arrangements, not equidistant and two A microstructure that can be controlled to change densely and laterally away from the entrance surface; a discontinuous three-dimensional strip with a long narrow and parallel arrangement, and an isometric density change Microstructure; a plurality of discontinuous three-dimensional cones arranged in an array, unequal distances, and controllable density-changing microstructures that are densely spaced away from the entrance surface; having a plurality of narrow and long arrays A discontinuous three-dimensional cone-shaped, equidistant and densely-changing microstructure; a spherical microstructure having a plurality of discontinuous three-dimensional arrays arranged in an array, unequal distances, and controllly thinning at both sides away from the entrance surface a densely-changed microstructure; a spherical microstructure having a plurality of discontinuous stereoscopic arrays arranged in an array, an isometrically densely-changed microstructure; a plurality of discontinuous arc-shaped pyramidal microstructures arranged in an array, not equidistantly a microstructure that is controlled to be densely and densely changed from the side to the light entrance surface; and a microstructure having a plurality of discontinuous arc-shaped pyramid microstructures arranged in an array and equidistantly varying density. A backlight module having a light guiding device includes: a light source; a light guiding layer defining a light incident surface; the light incident surface is provided by the side light source to emit light from the light incident surface In the light guiding layer, a reflective layer can reflect the light that is incident on the reflective layer back to the light guiding layer; a uniform light layer whose surface is farther from the side of the reflective layer is a light-emitting surface, the light guiding layer is located between the reflective layer and the light-homogenizing layer, and the light-emitting surface is perpendicular to the light-incident surface, and at least a portion of the light in the light guiding layer can be from the light-emitting surface And the at least one optical film covering the light-emitting surface; wherein the light-reflecting layer and the light-homogenizing layer are co-extruded integrally, and the reflective layer and the light guiding layer are not formed. An air interface; and a reflective surface is defined between the light guiding layer and the reflective layer, and a stereoscopic microstructure is disposed on the reflective surface; and the aspect ratio data of the microstructure of the reflective surface The system is in accordance with the following relationship: And n1 <n2; wherein H2 is the depth of the microstructure of the reflective surface, P2 is the width of the microstructure of the reflective surface, n1 is the refractive index of the light homogenizing layer, and n2 is the refractive index of the light guiding layer rate. A liquid crystal display having a light guiding device includes: a side light source; a light guiding layer defining a light incident surface; the light incident surface is provided by the side light source to emit light from the light incident surface a light-reflecting layer, wherein the light that is incident on the reflective layer in the light-guiding layer is reflected back to the light-guiding layer; a light-homogenizing layer having a light-emitting surface that is farther away from the side of the reflective layer The light guiding layer is located between the reflective layer and the light absorbing layer, and the light emitting surface is perpendicular to the light incident surface, and at least a portion of the light in the light guiding layer can be emitted from the light emitting surface. At least one optical film covering the light-emitting surface; and a liquid crystal panel located on a side of the optical film that is farther away from the light-guiding layer; wherein the reflective layer is shared with the light-homogenizing layer The extrusion is integrally formed, and there is no air interface between the reflective layer and the light guiding layer; and a reflecting surface is defined between the light guiding layer and the reflective layer, and a stereoscopic shape is disposed on the reflective surface Structure; and the aspect ratio data structure of the reflective surface meets the following Bollard: And n1 <n2; wherein H2 is the depth of the microstructure of the reflective surface, P2 is the width of the microstructure of the reflective surface, n1 is the refractive index of the light homogenizing layer, and n2 is the refractive index of the light guiding layer rate.