Claims
- 1. A liquid crystal display device comprising:a liquid crystal cell array; a light guide plate disposed on a rear or front side of said liquid crystal cell array and for lighting said liquid crystal cell array from the rear or front side; and a light source disposed on one side end face of said light guide plate and for radiating light from said one side end face of said light guide plate into said light guide plate, wherein a plurality of concave dots are formed in a surface of said light guide plate opposite to a light emitting surface of said light guide plate which emits light to said liquid crystal cell array so that light incident on said light guide plate from said light source is reflected at said concave dots in a direction toward said light emitting surface of said light guide plate, and wherein each of said concave dots is shaped like a triangle with a sectional inclination angle of from 50 to 60° in sectional view and shaped like an approximate rectangle or square in plan view in a direction perpendicular to said opposite surface of said light guide plate and disposed so that a long side of said approximate rectangle or a side of said approximate square is approximately parallel with a longitudinal direction of said light source.
- 2. A liquid crystal display device according to claim 1,wherein said approximate rectangle or square in each of said concave dots has short sides with a length of from 10 to 100 μm, and long sides with a length not smaller than 1.5 times as large as said short side length and not larger than 500 μm, and wherein each of said concave dots has a depth of from 2 to 100 μm.
- 3. A liquid crystal display device according to claim 1,wherein concave dots each having a shape other than that stated above are formed partially in the surface of said light guide plate opposite to said light emitting surface of said light guide plate.
- 4. A liquid crystal display device according to claim 1,wherein said concave dots are arranged individually at random over the whole light guide plate.
- 5. A liquid crystal display device according to claim 1,wherein the number of said concave dots per unit area in said light guide plate increases as said unit area is farther from said light source.
- 6. A liquid crystal display device according to claim 1,wherein the size of each of said concave dots in said light guide plate increases as said concave dot is farther from said light source.
- 7. A liquid crystal display device according to claim 1,wherein the number of said concave dots per unit area in said light guide plate as viewed along a direction parallel with the longitudinal direction of said light source increases as said unit area is farther from the center.
- 8. A liquid crystal display device according to claim 1,wherein the size of each of said concave dots in said light guide plate as viewed along a direction parallel with the longitudinal direction of said light source increases as said unit area is farther from the center.
- 9. A liquid crystal display device according to claim 1,wherein a thickness in a position of said light guide plate decreases as said position is farther from said light source.
- 10. A light guide plate into which light is introduced from a light source disposed on a side end face of said light guide plate,wherein a plurality of concave dots are formed in a surface of said light guide plate opposite to a light emitting surface of said light guide plate so that light incident on said light guide plate from said light source is reflected at said concave dots in a direction toward said light emitting surface of said light guide plate, and wherein each of said concave dots is shaped like a triangle with a sectional inclination angle of from 50 to 60° in sectional view and shaped like an approximate rectangle or square in plan view in a direction perpendicular to said opposite surface of said light guide plate and disposed so that a long side of said approximate rectangle or a side of said approximate square is approximately parallel with a longitudinal direction of said light source.
- 11. A light guide plate according to claim 10,wherein said approximate rectangle or square in each of said concave dots has short sides with a length of from 10 to 100 μm, and long sides with a length not smaller than 1.5 times as large as said short side length and not larger than 500 μm, and wherein each of said concave dots has a depth of from 2 to 100 μm.
- 12. A light guide plate according to claim 10,wherein concave dots each having a shape other than that stated above are formed partially in the surface of said light guide plate opposite to said light emitting surface of said light guide plate.
- 13. A light guide plate according to claim 10,wherein said concave dots are arranged individually at random over the whole light guide plate.
- 14. A light guide plate according to claim 10,wherein the number of said concave dots per unit area in said light guide plate increases as said unit area is farther from said light source.
- 15. A light guide plate according to claim 10,wherein the size of each of said concave dots in said light guide plate increases as said concave dot is farther from said light source.
- 16. A light guide plate according to claim 10,wherein the number of said concave dots per unit area in said light guide plate as viewed along a direction parallel with the longitudinal direction of said light source increases as said unit area is farther from the center.
- 17. A light guide plate according to claim 10,wherein the size of each of said concave dots in said light guide plate as viewed along a direction parallel with the longitudinal direction of said light source increases as said unit area is farther from the center.
- 18. A light guide plate according to claim 10,wherein a thickness in a position of said light guide plate decreases as said position is farther from said light source.
- 19. A method for producing a light guide plate according to claim 10, comprising the steps of:(a) applying a photo resist onto a silicon crystal substrate covered with a silicon oxide film, and then forming a pattern of said concave dots on said photo resist by photolithography; (b) etching said silicon oxide film with said photo resist as a mask, and then removing said photo resist; (c) forming said concave dots in said silicon crystal substrate by anisotropically etching said silicon substrate with said silicon oxide film as a mask, and then removing said silicon oxide film; (d) forming a metal film as a base of plating on said silicon crystal substrate, plating said silicon crystal substrate with nickel by use of said metal film as an electrode to thereby form a master stamper of a nickel plating sheet, and then separating said master stamper from said silicon crystal substrate; (e) forming a mother stamper by plating said master stamper, and then separating said mother stamper from said master stamper; (f) forming a stamper for molding by plating said mother stamper, and then separating said molding stamper from said mother stamper; and (g) attaching said molding stamper to a molding equipment, and producing said light guide plate by molding.
Priority Claims (1)
Number |
Date |
Country |
Kind |
11-124411 |
Apr 1999 |
JP |
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CROSS-REFERENCE TO RELATED APPLICATION
This application is related to U.S. patent application Ser. No. 08/938703 entitled “LIQUID CRYSTAL DISPLAY DEVICE”, filed on Sep. 26, 1997 is herein incorporated by reference.
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