TW200420969A - Manufacturing method of light-guiding apparatus for using in backlight of liquid crystal display - Google Patents

Abstract

Due to lights with different wavelengths having different indexes of refraction in a liquid crystal, a retadation between lights with different wavelengths occurs and causes the problem of viewing angle of the liquid crystal display. The present invention provides a manufacturing method of light-guiding apparatus of a liquid crystal display to form light-guiding pillars having a characteristic of total reflection as a fiber. The light from back light module through the light-guiding pillars enters the liquid crystal at an incident angle smaller than 150 for reducing the retadation between lights with different wavelengths.

Description

200420969 V. Description of the invention (1) ^ * 1. [Technical field to which the invention belongs] The present invention relates to a method for manufacturing a backlight cluster element for a liquid crystal display, and particularly to a backlight cluster element for a wide viewing angle twisted nematic liquid crystal display. Pieces manufacturing method. 2. [Previous Technology] Since the liquid crystal molecules are all formed by plate-like or rod-like molecules, there are some differences in the physical properties of the molecules in the parallel or vertical direction of the long axis of the molecules, so the liquid crystal molecules are also called anisotropic性 crystalline. For a nematic type liquid crystal ¥ (Nematic type liquid crystal), there are two refractive indices, namely the refractive index no in the direction of the long axis of the vertical liquid crystal and the refractive index ne in the direction of the long axis of the parallel liquid crystal. A single optical axis crystal with two different refractive indices (for example: liquid crystal), that is, a birefringence crystal (birefringence crystal) has the following optical characteristics: · When a non-polarized light enters the liquid crystal, this light will be divided into two Polarized polarized lights that are orthogonal to each other have different velocities and different angles of refraction. Therefore, the 'liquid crystal' has a characteristic of polarizing light. Moreover, the liquid crystal material has a flow characteristic, so only a very small 彳 p force is required, and the liquid crystal molecules can move to produce different alignment conditions. Taking the most common nematic liquid crystal as an example, it can cause liquid crystal molecules to turn by the action of an electric field. When no liquid is applied between the upper and lower glass of the LCD panel

Page 7 200420969 V. Description of the invention (2) When the voltage is applied, the arrangement of the liquid crystal will be determined by the alignment film of the upper and lower glass. For a twisted nematic (TN) liquid crystal display, the angle difference between the upper and lower alignment films is just 90 degrees, so the arrangement of liquid crystal molecules will automatically rotate 90 degrees from top to bottom. When incident light passes through it, With one side of the polarizing plate, only polarized light waves remain. When passing the liquid crystal molecules, because the liquid crystal molecules rotate a total of 90 degrees, when the light wave reaches the other polarizing plate, the polarization direction of the light wave is turned exactly 90 degrees. The angle between the two polarizing plates is also exactly 90 degrees, so the light can pass smoothly. However, if a voltage is applied between the upper and lower glass, when the liquid crystal molecules are affected by the electric field, the arrangement direction of the liquid crystal molecules will tend to be parallel to the electric field direction, and the arrangement of the liquid crystal molecules will become standing. At this time, a unidirectionally polarized light wave passing through one of the polarizing plates will not change the polarization direction when passing through the liquid crystal molecules, so it cannot pass through the other polarizing plate. Therefore, the liquid crystal display mainly uses two polarizing plates and the liquid crystals in them to pass different electric fields to the liquid crystals in different regions to generate different liquid crystal directions, so that the liquid crystals in different regions can be displayed differently according to the desired graphics. The performance of brightness. The red, blue and green (RG B) three primary color filters (c ο 1 〇rfi 11 er) are used to give different brightness to the red, blue, and green three-color areas of a display unit, and the three colors can be mixed and expressed. Different colors enable the LCD to display color or even full-color images. However, because liquid crystals have different phase delays for light of different wavelengths (colors), that is, liquid crystals have different refractive indexes for different wavelengths, and light of different wavelengths.

Page 8 200420969 V. Description of the invention (3) The incident angle and refraction angle of the line cannot be completely the same. As a result, when viewing the liquid crystal display at different viewing angles, different image performances will be observed, which will limit the viewing angle of the liquid crystal display. In the conventional art, a wide viewing angle compensation film is added to the outside of the liquid crystal display to compensate for the phase delay between different wavelengths, but the wide viewing angle compensation film cannot compensate all the phase delays of different angles at the same time. Another method to deal with the problem of phase delay between different wavelengths is to direct light as much as possible into the liquid crystal panel, so that the problem of phase delay between different wavelengths can be reduced. Then, a diffusion film is used and placed outside the liquid crystal panel to scatter the light passing through the liquid crystal panel to achieve the effect of wide viewing angle. Generally, the incident angle range of light entering the liquid crystal panel is only within 15 degrees, and the phase delay caused by different wavelengths is within an acceptable range. As shown in the first figure, it is a schematic diagram of a high-focusing microlens array of the conventional technology. The light is incident from below the light guide array 10, the light is collected by the light guide array 10, and passes through the transparent multilayer substrate 20 (for simplicity, the multilayer structure is not drawn), and then by the lens above Array 30 gathers the rays so that the angular range of the rays is within a range of 15 degrees. The element size of the light guide array 10 is in the millimeter (mm) level, so it is difficult for the light incident on the light guide array 10 to reach the condition of total reflection, so its light collection efficiency is poor, and the use of the multilayer substrate 20 also There will be light loss. The effect on the uniformity of the light guide array distribution and the unidirectionality will also be poor. It has also been proposed to use optical fibers to guide light so that light can enter the liquid crystal panel almost vertically, but it is difficult to control the optical fibers so that

Page 9 200420969 V. Description of the invention (4) On the substrate, there are problems in the manufacturing process. 3. [Content of the invention] In view of the above background of the invention, the twisted nematic liquid crystal in the conventional art has different refractive indexes for light of different wavelengths, resulting in retardation of light of different wavelengths obliquely entering the liquid crystal panel, affecting the liquid crystal. The viewing angle of the display. However, the high-convergence microlens array method is inferior in terms of uniform distribution, single directionality, and high convergence efficiency. Therefore, the main object of the present invention is to provide a method for manufacturing a light guide device for a backlight of a liquid crystal display, so as to achieve a total reflection effect similar to that of an optical fiber, to achieve a high concentration capability, and to generate a collection light with a high collection efficiency. Another object of the present invention is to provide a method for manufacturing a light guide device for a backlight of a liquid crystal display, so as to obtain a high degree of unidirectionality of concentrated light. Another object of the present invention is to provide a method for manufacturing a light guide device for a backlight of a liquid crystal display, so that the distribution of the array of light guide tubes can be more uniform. Another object of the present invention is to provide a method for manufacturing a light guide device for a backlight of a liquid crystal display, so that a wider viewing angle can be achieved with a twisted nematic liquid crystal display. Another object of the present invention is to provide a light guide for a backlight of a liquid crystal display.

Page 10 200420969 V. Description of the invention (5) The device manufacturing method can generate a highly concentrated light guide array on a single substrate, which can reduce the occurrence of light loss. According to the above-mentioned object, the present invention provides a method for manufacturing a light guide device for a backlight of a liquid crystal display. The method for manufacturing a light guide device for a backlight of a liquid crystal display of the present invention is to distribute a plurality of pseudo-micron-sized particle photomasks on a substrate surface, and then expose the substrate surface on which a plurality of micron-sized particle photomasks are dispersed by ultraviolet light exposure, and remove the plurality of micrometers. Level particle mask, and etch the substrate to remove the part exposed to ultraviolet light to form a plurality of columnar light guide pillars. Alternatively, a plurality of micron-level particle photomasks are spread on a glass substrate surface, and the surface of the substrate is not covered by a plurality of micron-level particle photomasks with oxygen plasma (0 × yge η p 1 asmaetching) to form / multiple A cylindrical light guide, and removing the plurality of micron-sized particle photomasks. ,, the high method of light train method, the method of production to the party, the production of the party to reduce the curvature of the production system is a twistable system, single set, and the array is installed, the mirror can be high light array uniform light guide light beam uniform Microconducting hubs are more conductive and highly specular. Beam beam to beam back beam to the corner of the city back to the collector set the visual height device, to the high column of the display of the effect of the array of technology and the crystal tube tube more technical shot, the liquid plate light reaches the liquid reflection . Ming Fengdao can learn all kinds of hair bundles in a single set of books, the plate is more than the fiber-supplying on the raw surface to increase the luminosity and crystals, Ming-like effect of this hair bundle. Cause of loss

200420969 V. Description of the invention (6) IV. [Embodiments] Some embodiments of the present invention will be described in detail as follows. However, in addition to the detailed description, the present invention can be widely implemented in other embodiments, and the scope of the present invention is not limited, which is subject to the scope of subsequent patents. Furthermore, in order to provide a clearer description and easier understanding of the present invention, the parts in the illustration have not been drawn according to their relative sizes. 'Some dimensions have been exaggerated compared to other relevant dimensions; irrelevant details have not been completely drawn. Out for simplicity of illustration. Although the optical fiber is a very good light guiding element, the optical fiber cannot be used as a light guiding device for a backlight because the optical fiber is not easily formed on a substrate. The spirit of the present invention is to form a light guide tube with a fiber-like property (that is, the property that light transmitted inside the fiber will be concentrated in the fiber due to total reflection) on a substrate, so that the light entering the light guide tube can be The total reflection operation # is gathered in the light guide tube to achieve a high-efficiency bundling effect. First, as shown in the second figure, a micron-sized particle mask 50 is sprayed on a substrate 40. A preferred spraying situation is that the particle mask 50 covers the entire substrate 40 and the particle mask 50. There is no overlap between them. The particle mask 50 can be reused repeatedly, and the preferred particle mask 50 is a spherical body of uniform size. The material of the general substrate 40 can be used according to the different light rays.

Page 12 200420969 (7) and the irradiated light using a high-resolution mask 50 material 60 line from the substrate 40 to develop, wash the liquid crystal after receiving exposure columnar. The device is cylindrical. The best condition is the bigger the better. V. Description of the invention Proper optional can block light, and can be a particle light step. Photonic material in developing solution. The four pillars shown in Figure 4 are circular light guide substrates with a gap of 40. The larger the area, the lighter the material of the line. Sub-materials as qualitative. Next, the five images of the sub-mask 50 at the UV end are subjected to the backlight of the UV display and developed. The five images are manufactured by another method, the light guide column 80, and the gap 90 is used to collect more materials. For example, the substrate 40 As shown in the third figure, the irradiation substrate is exposed, and the light guide mounting portion 70 for the light irradiating portion is set to have a light guide mounting gap 90 according to the present invention as the light having a smaller size. For the particle mask 50, the ultraviolet light is selected for exposure. The glass is used as the exposure material. The exposure is 40 °. The side view of the rear side of the LCD I indicator, the space between the light guide 80 and the light guide 80 occupied by the light guide 80 is micron level, and the part other than the light guide 80 is ^ air, so it enters the light guide. The light of the light column 80 will generate a total reflection phenomenon around the inside of the light guide column 80, so the light collection efficiency of the light guide column is very high. In addition, the single device of the light device avoids the problem of prophecy caused by multiple layers of material. The arrangement of the V-beams can have several different arrangements. The fourth figure illustrates only one arrangement method, and is not intended to limit the arrangement manner of the light guide device of the present invention. In addition to materials that can react with light, glass or quartz glass can also be used.

200420969 V. Description of the invention (8) Glass is used as the substrate of the light guide device. The etching method can be changed to an oxygen plasma etching method. The manufacturing process is modified as follows: a plurality of micron-sized particle photomasks are scattered on the surface of a glass substrate; the oxygen plasma etching is not covered by the micron-sized particle photomasks to shield the substrate. Surface to form a plurality of columnar light guides, and remove a plurality of micron-sized particle photomasks. The material of the particle mask must be able to resist the etching effect of oxygen plasma etching. Therefore, a light guide device for a liquid crystal display backlight can be formed on a thin film electro-crystalline glass substrate of a liquid crystal panel. Furthermore, the light emitted from the backlight module passes through the light guide device manufactured by the method for manufacturing a light guide device for a liquid crystal display backlight according to the present invention, so that the incident angle of the light into the twisted nematic liquid crystal panel is within 15 degrees. When the light penetrates the LCD panel, the diffused light diffuses in the direction of the light, so that the liquid crystal display reaches a wider viewing angle. Therefore, compared with the conventional method of high-concentration microlens array, the present invention provides a method for manufacturing a light guide device for a backlight of a liquid crystal display, which achieves a high-concentration capability with a total reflection effect similar to that of an optical fiber, so as to generate high-concentration efficiency. The beam of light and achieve a high degree of single-directionality of the beam of light. In addition, the high-convergence light guide array on a single substrate manufactured by the method for manufacturing a light guide device for a backlight of a liquid crystal display according to the present invention can reduce the distribution of light loss, and the light guide tube array can be more uniform and twisted nematic Type LCD panel can achieve a wider viewing angle.

Page 14 200420969

Page 15 200420969 The diagram is a brief illustration of the structure of a highly concentrated micro lens array in the conventional art. The second diagram is a schematic diagram of the steps of spraying a particle mask on a substrate. The third diagram is the substrate. A schematic view of exposure; the fourth diagram is a top view of a light guide device for a backlight of a liquid crystal display according to a preferred embodiment of the present invention; and the fifth diagram is a light guide device manufactured by the method of a light guide for a backlight of a liquid crystal display according to the present invention Side view. Symbols of the main parts: 1 0 light guide array 20 multi-layer substrate 3 0 lens array 4 0 substrate 5 0 particle mask 60 exposure light 7 0 substrate exposure 80 cylindrical light guide 90 gap between light guides

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Claims (1)

200420969 1. A liquid crystal display that spreads a plurality of micrometers and irradiates the surface of the panel with ultraviolet light exposure; and removes the plurality of micrometers to remove a column that receives ultraviolet light. The light guide for the backlight is provided with a particle mask on a portion where the plurality of particle masks are dispersed, and the irradiated part, a manufacturing method, includes: a substrate surface; the substrate of the dichroic particle mask is etched into the substrate to form a plurality Each column-shaped light guide 2 · The liquid crystal manufacturing method according to item 丨 of the application, wherein the material of the substrate is a light guide device for moonlight and a molecular material. 3 · The manufacturing method of liquid crystal __ ^ North as described in the scope of patent application, wherein the plurality of columnar guides and 12 are light guide devices for moonlight crystal displays. The column is used for twisting the nematic liquid. 4. The manufacturing method of the liquid crystal display north according to the scope of the patent application, wherein the plurality of columnar light guides ^ light guide devices for moonlight are made of glass. 5 · The manufacturing method of liquid crystal _ — _ as described in item 1 of the patent application scope, further comprising a diffusion film on the outer side of the light sheet glass substrate of the light guide device for moonlight. ^, Set the color filter of the display 1 · If the liquid crystal display crybite of item 1 of the scope of patent application, 2 manufacturing method, wherein the plurality of micron-scale faces ^ @ 光 用光 导 装置 The photomask is spherical. 200420969 VI. Application for Patent Scope 7 · As in the method for manufacturing a light guide device for a backlight of a liquid crystal display according to item 1 of the patent application, wherein the plurality of columnar light guides pair incident light entering the plurality of columnar light guides, incident on Total reflection occurs on the inside edge surface. 8. The method of manufacturing a light guide device for a backlight of a liquid crystal display according to item 1 of the patent application, wherein the plurality of micron-sized particle photomasks cover the surface of the substrate, and the plurality of micron-sized particle photomasks do not overlap with each other. 9 · The method for manufacturing a light guide device for a backlight of a liquid crystal display according to item 1 of the patent application, wherein the substrate is a single substrate. A method for manufacturing a light guide device for a backlight of a liquid crystal display, comprising: dispersing a plurality of micron-sized particle photomasks on a glass substrate surface; engraved with an oxygen plasma surname without being shielded by the plurality of micron-level particle photomasks. Surface to form a plurality of columnar light-guiding pillars; and removing the plurality of micron-sized particle photomasks by flying, μ soil. ii • If the method of manufacturing a liquid crystal display in the north of the scope of the patent application is No. 10, the material of the glass substrate is a light guide device for G ^ 12. If the method of manufacturing the liquid crystal display in the scope of the patent application is No. 10 'Where the glass substrate is the thin film of the X-ray display device for the moonlight 200420969 6. Scope of patent application Crystal glass substrate. 1 3. The method for manufacturing a light guide device for a backlight of a liquid crystal display according to item 10 of the application, wherein the plurality of columnar light guides are used for twisted nematic liquid crystal displays. 1 4. The method for manufacturing a light guide device for a backlight of a liquid crystal display according to item 10 of the scope of patent application, wherein the material of the plurality of columnar light guides is glass. 1 5. The method for manufacturing a light guide device for a backlight of a liquid crystal display according to item 10 of the patent application scope, further comprising a diffusion film on the outside of the color substrate and the light sheet glass substrate of the liquid crystal display. 16. The method for manufacturing a light guide device for a backlight of a liquid crystal display according to item 10 of the patent application, wherein the plurality of micron-sized particle photomasks are spherical particle photomasks. 1 7. The method for manufacturing a light guide device for a backlight of a liquid crystal display according to item 10 of the patent application, wherein the plurality of columnar light guides are incident on the inner side surface to the incident light entering the plurality of columnar light guides. Total reflection occurs from time to time. 1 8. The method for manufacturing a light guide device for a backlight of a liquid crystal display according to item 10 of the patent application scope, wherein the plurality of micron-sized particle photomasks cover the substrate Page 19 200420969 Sixth, the scope of the patent application, and the plurality of micron-level particle photomasks do not overlap each other. 19. The method for manufacturing a light guide device for a backlight of a liquid crystal display according to item 10 of the patent application, wherein the substrate is a single substrate. Page 20