Thin-plate storage container

• US 20080007969A1
• Filed: 08/22/2007
• Published: 01/10/2008
• Est. Priority Date: 08/30/2002
• Status: Abandoned Application

• Current Assignee: Kimoto Company Limited
• Original Assignee: Kimoto Company Limited
• Inventors: Etori, Hideki
• Application Number:
  US11/892,337
• Publication Number:
  US 20080007969A1
• Time in Patent Office: Days
• US Class Current: 362/618
• CPC Class Codes: G02B 5/021 the diffusion taking place at the element's surface, e.g. by means of surface roughening or microprismatic structures
• CPC Class Codes: G02B 5/0278 used in transmission
• CPC Class Codes: G02F 1/133606 including a specially adapted diffusing, scattering or light controlling members

Abstract

A light control film having a refractive index n and an uneven, irregular surface pattern provides a reasonable level of light diffusion without a glare problem provided, for any cross-section perpendicular to the base plane of the film, the average of absolute values of slope θ_ave of a curve along the edge of the cross-section contoured by the rough surface pattern (profile curve) is at least 78-34 n degrees and no higher than 118-34 n degrees, or the average of absolute values of slope θ_ave of a profile curve to the length L1 of a straight line defined by the intersection of the base plane and the cross-section satisfies the following formula (3) or (4) for substantially all cross-sections.
θ_ave÷Lr×n²≧40  (3)
50≦θ_ave×Lr×n²≦135  (4)

Claims

1. A light control film having a rough surface pattern defining, for each cross-section perpendicular to a base plane of the film, a profile curve along an edge contoured by the rough surface pattern, wherein for substantially all cross-sections perpendicular to a base plane of the film, the profile curve has an average of absolute values of slope to said base plane θ

_ave which is at least 20° and

no greater than 75°

.

3. A light control film according to claim 1, wherein difference in said average of absolute value of slope between cross-sections in different directions is within 30 degrees.

4. A light control film according to claim 1, wherein the average of absolute values of slope θ

ave of said profile curve increases gradually from a cross section in a first direction towards another cross-section in a second direction perpendicular to said first direction.

5. A light control film according to claim 1, wherein the slope of said profile curve to the base plane increases or decreases gradually from one end towards another end of the film.

6. A backlight comprising a light control film according to claim 1, and a light source, wherein said light control film has a profile curve on a cross-section approximately orthogonally crossing a longitudinal axis of the light source which, divided into segments at a certain interval, has an average of absolute values of slope calculated for all segments facing the light source which increases towards the light source.

7. A backlight comprising a light control film according to claim 1, and a light source, wherein said light control film has a profile curve on a cross-section approximately orthogonally crossing a longitudinal axis of the light source which, divided into segments at a certain interval, and has an average of absolute values of slope calculated for all segments facing away from said light source which decreases towards the light source.

8. A backlight device comprising a light guiding plate, at least one light source located at an edge thereof, said light guiding plate having a light emergent surface approximately orthogonal to said edge, and a light control film according to claim 1 located on the light emergent surface of said light guiding plate.

9. A backlight device comprising a light control film according to claim 1, a light source, and a light diffusing material between said light source and said light control film.

10. A backlight device comprising a light guiding plate equipped with a light source at least on one end and having a light emergent surface almost orthogonally crossing said one end, and a light control film located on the light emergent surface of said light guiding plate, wherein said light control film is a light control film according to claim 4.

11. A backlight device according to claim 10, wherein the light control film is located so that the one direction is parallel to the one end of the light guiding plate where the light source is located.

12. A light control film according to claim 1 wherein θ

ave is at least 25 degrees and no greater than 60 degrees.

14. A light control film according to claim 1 wherein θ

ave is at least 30 degrees and no greater than 50 degrees.

16. A backlight comprising a light control film according to claim 9, and a light source, wherein said light control film has a profile curve on a cross-section approximately orthogonally crossing a longitudinal axis of the light source which, divided into segments at a certain interval, has an average of absolute values of slope calculated for all segments facing the light source which increases towards the light source.

17. A light control film according to claim 1, wherein the rough surface pattern is formed by two-dimensionally arranging protrusions, each protrusion having a profile curve with an average of absolute values of slope to the base plane θ

ave which is at least 20° and

no greater than 75°

.

2. A light control film including a surface layer, said surface layer having a rough surface pattern defining, for each cross-section perpendicular to a base plane of the film, a profile curve along an edge contoured by the rough surface pattern, said surface layer formed of a material having a refractive index n, wherein for substantially all cross sections perpendicular to a base plane of the film the profile curve has an average of absolute values of slope to said base plane θ

ave which is at least 78-34 n degrees and no greater than 118-34 n degrees.

13. A light control film according to claim 2 wherein θ

ave is at least 25 degrees and no greater than 60 degrees.

15. A light control film according to claim 2 wherein θ

ave is at least 30 degrees and no greater than 50 degrees.

18. A light control film according to claim 2, wherein the rough surface pattern is formed by two-dimensionally arranged protrusions, each protrusion having a profile curve with an average of absolute values of slope to the base plane θ

ave which is at least 20° and

no greater than 75°

.

19. A light control film according to claim 2, wherein the refraction index of the material is 1.3-1.7.

20. A light control film according to claim 2, wherein the material includes no light diffusing agent.