TWI261128B - Method of manufacturing light guide plate - Google Patents

Abstract

The present invention relates to a method of manufacturing a light guide plate, which includes the following steps: providing a base with a light emitting surface thereon; forming an intervening layer whose refraction index is lower than the base's by doping; forming a plurality of grooves on the intervening layer, and a depth of the grooves is less than a thickness of the intervening layer.

Description

1261128 V. INSTRUCTION DESCRIPTION π) Technical Field of the Invention The present invention relates to a method of fabricating a light guide plate, and more particularly to a method of fabricating a light guide plate having uniform light emission. [Prior Art] Since the liquid crystal in the liquid crystal display panel itself has no illuminating property, in order to achieve the display effect, it is necessary to provide a liquid crystal display panel with a light source device, such as a backlight module, whose function is to provide sufficient brightness and uniform distribution to the liquid crystal display panel. The surface light source. Referring to the first figure, the backlight module of the prior art is mainly composed of a light source 5, a light source cover 6, a light guide plate 3, a reflection plate 4, a diffusion plate 2, and two light collecting sheets 1. The light source 5 is a line light source, which is mainly composed of an electroluminescence lamp (EL) and a cathode fluorescent lamp (CCFL), which are disposed on the side of the light guide plate 3, and the light source cover 6 is provided. The cooperation transmits light to the light guide plate 3. The light guide plate 3 functions to guide the light emitted from the light source 5 to exit from the light exit surface 7 while improving the luminance and uniformity of the display panel (not shown). The reflector 4 is disposed on one side of the bottom surface 8 of the light guide plate 3 to reflect the light emitted from the bottom surface 8 of the light guide plate 3 into the light guide plate 3 to improve the utilization of light. The lower surface of the diffusion plate 2 is provided with minute projections (not shown) for scattering the light incident on the diffusion plate 2 to smooth the pattern of the display panel. The light collecting sheet 1 is also called a seesaw, and its function is to concentrate the light to improve the light output of the backlight module and reduce the power consumption. However, the two light collecting sheets 1 and the light guiding plate 3 of the backlight module are separately manufactured and assembled, so that the structure of the entire moonlight module is complicated and configured.

1261128 V. Description of invention (2) Inconvenience. Please refer to the second and third figures together, which is a schematic diagram of a light guide plate disclosed in the patent No. 0 0 2 4 6 5 5 5 of the Chinese mainland published on May 23, 2001. In a partially enlarged view, the light guide plate 10 includes a body 2, a diffusion film 13, a plasma film 14 and a reflection film 11. The cross section of the body 12 is substantially wedge-shaped, and the light-emitting surface 18 has a plurality of fine uniform V-shaped groove structures 16; the diffusion film 13 and the plasma film 14 are sequentially attached to the surface of the V-shaped groove structure 16; The bottom surface of 2 is a network of 1 5 complex arrays. The body 1 2 of the light guide plate 10 and the plurality of V-shaped grooves 16 are integrally formed by injection molding. Referring to the fourth figure, the light guide plate formed by the method has a plurality of V-shaped groove structures. The light rays are refracted after passing through the V-shaped groove structure 16. The angle of refraction A is greater than the incident angle α. The light guide plate 10 has concentrated light to achieve the same light collecting effect as the light collecting sheet, and the backlight module of the light guiding plate 10 can save the cost of the light collecting sheet. However, the light guide plate 10 and the V-shaped groove 16 are integrally formed and formed. Since the V-shaped groove 16 is formed on the body 1 2 of the light guide plate 10, the V-shaped groove 16 has a collecting effect, that is, due to the air. The refractive index is small, and when the light is emitted from the V-shaped groove structure 16, it will converge toward the convex portion 161 to narrow the light, thereby affecting the light-emitting property of the light guide plate 10, reducing the uniformity of light emission, and even Form a dark band. In order to eliminate the dark band formed by the V-shaped groove structure 16, the shape and pitch of the V-shaped groove structure 16 are usually changed to eliminate the dark band, but these methods can only weaken and cannot completely eliminate the dark band. The belt is produced, and the design of the shape and pitch of the V-shaped groove structure 16 is complicated. In view of this, a total of a light guide plate with uniform light output and simple design is provided.

1261128 V. Description of invention (:3) The production method is really necessary. SUMMARY OF THE INVENTION An object of the present invention is to provide a method for fabricating a light guide plate, wherein the light guide plate produced by the method has uniform light emission and simple design. Another object of the present invention is to provide a method for fabricating another light guide plate, wherein the light guide plate produced by the method has uniform light emission and simple design. The manufacturing method of the light guide plate of the present invention comprises the steps of: forming a body having a light emitting surface; and, starting from the light emitting surface, doping the body to form a dielectric layer, the dielectric layer having a refractive index smaller than the body a refractive index of the doped region; forming a plurality of grooves on the dielectric layer, the groove having a depth less than a thickness of the dielectric layer. Another method for fabricating a light guide plate comprises the steps of: forming a body having a light exiting surface; forming a plurality of grooves on a side of the body adjacent to the light exiting surface; and doping the body from the groove Forming a dielectric layer having a refractive index smaller than a refractive index of the undoped region of the body, the dielectric layer having a thickness greater than the recess depth. Compared with the prior art, the light guide plate obtained by the method for fabricating the light guide plate of the present invention is formed on the side of the body adjacent to the light exit surface to form a plurality of grooves; from the beginning of the groove, doping the body to form a dielectric layer can be The dielectric layer is such that the groove is isolated from the body, that is, the interface condition at the groove in the prior art is body-air, and the interface condition at the groove of the present invention is changed to the dielectric layer-air according to the law of refractive index. : sina/sin/3= 11〆]^ where α and /3 are respectively 4 incident angles and refraction angles, η α and η /3 are respectively incident side,

1261128 V. Description of invention (4) Refractive index of the material of the refractive side. Since the refractive index of the dielectric layer is smaller than the refractive index of the body, when the light is emitted from the groove, the angle of refraction of the interface is the dielectric layer-air, and the angle of refraction is smaller when the interface is body-air, and the light caused by the groove is narrowed. The effect, so the dark band area does not appear due to the appearance of the groove, however, the light collecting effect of the groove still exists. In addition, in the design method of the light guide plate of the present invention, only the refractive index of the dielectric layer needs to be considered, and it is not necessary to change the shape and pitch of the V-shaped groove structure to avoid dark band generation, so the design is relatively simple. [Embodiment]

Referring to FIG. 5 to FIG. 7 , a schematic diagram of a method for fabricating a light guide plate according to the present invention, the method for fabricating the light guide plate 21 includes the following steps: first, a body 2 3 is formed, and a light surface is disposed thereon. 2 3 1 ; Then, from the light-emitting surface 2 3 1 , the body 2 3 is doped to form a dielectric layer 2 3 2 ; finally, a plurality of V-shaped grooves 2 3 4 are formed on the dielectric layer 23 2 . The material of the body 2 3 of the light guide plate 21 is a polymer resin material such as a polyacrylic acid resin, a polycarbonate, a polyethylene resin, or a polymethyl methacrylate, which may also be made of glass.

The dielectric layer 232 is a transparent dielectric layer having a refractive index smaller than that of the undoped region 23 3 of the body 2 3 , which is formed by ion implantation, and includes the following steps: first, using a plasma The generator generates charged ions to be implanted; and then accelerates by the electric field to cause the ions with high energy to enter the body 2 3 , and after multiple collisions with the atoms in the body 2 3 , the high energy ion energy gradually weakens and finally stops. motion. The plurality of V-shaped grooves 2 3 4 are equally spaced, which are processed by cutting

Page 8 1261128 V. Inventive Note (:5) Made or by lithography. Referring again to the eighth figure, the pitch L of the V-shaped groove 2 3 4 is 5 0 // in~1 0 0 az m, and the apex angle Θ is 75. ~1 1 5 °. The depth h of the V-shaped groove 243 is smaller than the thickness Η of the dielectric layer 232. Referring to the fourth and ninth drawings together, the V-shaped groove 243 and the undoped region 2 3 4 of the body 2 3 are effectively separated by the presence of the dielectric layer 232, that is, the V-shaped groove The interface condition of 2 3 4 is changed from the undoped region 2 3 3 -air to the dielectric layer 2 3 2 -air, since the refractive index of the dielectric layer 23 2 is smaller than the refractive index of the undoped region 23 3 , the light is When the V-shaped groove 2 3 4 is emitted, the interface is the dielectric layer 2 3 2 - the refraction angle of the air / 32 is the undoped area 2 3 3 - the angle of refraction / 3 i of the air is small, the V-shaped groove 2 is limited 3 4 The effect of narrowing the light, so there will be no dark bands in spring, and its light collecting effect still exists. However, the method of fabricating the light guide plate of the present invention is not limited to the embodiment. Referring to the fifth to seventh figures, the steps of the method for fabricating the light guide plate of the present invention can be appropriately changed. The V-shaped groove 2 3 4 can be formed first, and then doped, that is, a body 2 3 is first formed. A light-emitting surface 2 3 1 is disposed thereon; and a plurality of V-shaped grooves 2 34 are formed on the side of the body 23 adjacent to the light-emitting surface 231. From the V-shaped grooves 234, the body 2 3 is doped to form a a dielectric layer 2 3 2 , a refractive index of the dielectric layer 23 2 is smaller than a refractive index of the undoped region 23 3 of the body 2 3 , and a thickness of the dielectric layer 23 2 is greater than a depth of the V-shaped groove 2 34 ; The beneficial effects of changing Steps are as described above. Furthermore, the doping is not limited to the ion implantation method, and may also be formed by a diffusion method, that is, the impurities pre-doped into the body are first placed on the light-emitting surface 2 3 1 ; and then the impurities are exposed in a high-temperature environment. Incorporating into the body 2 3 , the V-shaped groove 2 3 4 can also be formed into other groove forms. Please refer to the tenth and eleventh drawings, the grooves are respectively formed into trapezoidal grooves 300 and curved shapes.

Page 9 1261128 V. _ Invention Description (6) Slot 4 0 0. In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and the scope of the present invention is not limited to the above-described embodiments, and those skilled in the art will be able to make equivalent modifications or variations in accordance with the spirit of the present invention. It should be covered by the following patent application.

Page 10 1261128 Brief Description of the Drawings The first figure is a perspective view of a prior art backlight module. The second figure is a schematic structural view of a prior art light guide plate. The third figure is a partial enlarged view of a prior art light guide plate. The fourth figure is a schematic diagram of light propagation of a light guide plate made by the prior art. Fig. 5 is a schematic view showing the steps of the main body manufacturing process of the light guide plate manufacturing method of the present invention. The sixth figure is a schematic diagram of the doping step of the method for fabricating the light guide plate of the present invention. Fig. 7 is a schematic view showing the steps of forming a v-groove in the method of fabricating a light guide plate of the present invention.

The eighth drawing is a front view of a light guide plate produced by the method for producing a light guide plate of the present invention. The ninth drawing is a schematic diagram of light propagation of a light guide plate produced by the method for fabricating a light guide plate of the present invention. The tenth drawing is a perspective view of a light guide plate having a trapezoidal groove formed by the method for fabricating a light guide plate of the present invention. The eleventh drawing is a perspective view of a light guide plate in which the groove is an arc groove formed by the method for fabricating the light guide plate of the present invention. [Component Symbol Description]

Light guide plate 21 Body 23 Light exit surface 231 Dielectric layer 232 Undoped area 233 V-shaped groove 234 Trapezoidal groove 300 Curved groove 400

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Claims (1)

1261128, the scope of the patent application 1. A method for fabricating a light guide plate, comprising the steps of: fabricating a body having a light exiting surface; and starting from the light exiting surface, doping the body to form a dielectric layer, the medium The refractive index of the layer is smaller than the refractive index of the undoped region of the body; a plurality of grooves are formed on the dielectric layer, the groove depth being less than the thickness of the dielectric layer. 2. The method of fabricating a light guide plate according to claim 1, wherein the grooves are equally spaced. 3. The method of fabricating a light guide plate according to claim 1, wherein the groove is a V-shaped groove. 4. The method of fabricating a light guide plate according to claim 1, wherein the groove is a trapezoidal groove. 5. The method of fabricating a light guide plate according to claim 1, wherein the groove is an arc groove. 6. The method of fabricating a light guide plate according to claim 1, wherein the dielectric layer is doped by ion implantation. 7. The method of fabricating a light guide plate according to claim 1, wherein the dielectric layer is doped by a diffusion method. 8. The method of fabricating a light guide plate according to claim 1, wherein the groove is formed by cutting. 9. The method of fabricating a light guide plate according to claim 1, wherein the groove is formed by photolithography etching. 10. The method of fabricating a light guide plate according to claim 1, wherein Page 12 1261128 6. The apex angle of the groove in the patent application range is 7 5 °~1 1 5 ° ◦ 11. The method of manufacturing the light guide plate according to claim 1, wherein the groove section The distance is 5 0 /2 in~1 0 0 // m. 12. The method of fabricating a light guide plate according to claim 1, wherein the material of the body is a polymer resin. 13. A method of fabricating a light guide plate, comprising the steps of: fabricating a body having a light exiting surface; forming a plurality of grooves on a side of the body adjacent to the light exiting surface; and integrating the body from the groove Forming a dielectric layer, the dielectric layer having a refractive index smaller than a refractive index of the bulk doped region, the dielectric layer having a thickness greater than the groove depth. 14. The method of fabricating a light guide plate according to claim 13 wherein the grooves are equally spaced. 15. The method of fabricating a light guide plate according to claim 13 wherein the groove is a V-shaped groove. 16. The method of fabricating a light guide plate according to claim 13 wherein the groove is a trapezoidal groove. 17. The method of fabricating a light guide plate according to claim 13 wherein the groove is an arc groove. 18. The method of fabricating a light guide plate according to claim 13 wherein the dielectric layer is doped by ion implantation. 19. The method of fabricating a light guide plate according to claim 13 wherein the dielectric layer is doped by a diffusion method. 2 0. The method for manufacturing a light guide plate according to claim 13 of the patent application scope, Page 13 1261128 VI. Scope of Application The groove is made by cutting. 21. The method of fabricating a light guide plate according to claim 13 wherein the groove is formed by photolithography. The method of manufacturing the light guide plate according to Item 13 of the patent application, wherein the apex angle of the groove is from 7 5 ° to 1 15 °. The manufacturing method of the light guide plate according to Item 13 of the patent application, wherein the pitch of the groove is 50 to 100 //m. 2 . The method of manufacturing the light guide plate according to claim 13 , wherein the material of the body is a polymer resin. Page 14