US5552907A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Light adjusting sheet having a sinusoidal surface and a non-optically flat surface and useable with an LCD
Assignee: Sekisui Chemical Co Ltd
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Filing: 1994-09-08
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Granted: 1996-09-03
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Expires: 2014-09-08
Abstract
Abstract A light adjusting sheet for a planar lighting device includes a plurality of convex and concave streaks arranged alternately and approximately parallel to each other on one surface. The streaks may have a cross section of a sine curve. Another light adjusting sheet consists of a plurality of single sheets each having the above configulation, stacked together. A planar lighting device includes the light adjusting sheet of the above configulation, wherein peak lines of the convex streaks and bottom lines of the concave streaks are arranged to make a predetermined angle with an axis of a linear light source. The liquid crystal display includes a liquid crystal display element placed on front of the planar lighting device of the above configulation.
Inventors
- 👤 Tomohiro Yokota
- 👤 Fumio Nishitani
- 👤 Hiroshi Ogawara
- 👤 Akihito Kubo
- 👤 Makoto Fujigami
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:58
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/0001; G02B6/0011; G02B6/0033; G02B6/0035; G02B6/0038; F; F21; F21V; F21V5/00; F21V5/04; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/1336; G02F1/133615
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
192 words
A light adjusting sheet for a planar lighting device which is placed at the front of a light emitting surface of a light guiding plate which composes said planar lighting device comprising: on one surface a plurality of convex regions each having a lateral cross section of a convex arc; and also on said one surface a plurality of concave regions each having a lateral cross section of a concave arc; wherein each convex region and each concave region are arranged alternately and approximately parallel to each other; said plurality of convex regions and concave regions having a cross-section of a sine curve represented by an equation Y=a·sin bX (1) wherein Y=coordinate in the depth-wise direction in μm units; X=coordinate in the lateral direction in μm units; "a"=factor in the range of 15 to 1500 in μm units; "b"=factor in the range of 0.005 to 1 in degree/μm units; and adjacent concave and convex regions being connected by a flat surface having an area equal to or less than 50% of the total area of the curved surfaces; and an average sheet thickness is in the range of 0.01 to 3 mm.
Claim 2
Dependent Claim
192 words
A light adjusting sheet for a planar lighting device which is placed at the front of a light emitting surface of a light guiding plate which composes said planar lighting device comprising: on one surface a plurality of convex regions each having a lateral cross section of a convex arc; and also on said one surface a plurality of concave regions each having a lateral cross section of a concave arc; wherein each convex region and each concave region are arranged alternately and approximately parallel to each other; said plurality of convex regions and concave regions having a cross-section of a sine curve represented by an equation Y=a·sin bX (1) wherein Y=coordinate in the depth-wise direction in μm units; X=coordinate in the lateral direction in μm units; "a"=factor in the range of 15 to 1500 in μm units; "b"=factor in the range of 0.005 to 1 in degree/μm units; and adjacent concave and convex regions being connected by a flat surface having an area equal to or less than 50% of the total area of the curved surfaces; and an average sheet thickness is in the range of 0.01 to 3 mm.
Claim 3
Dependent Claim
26 words
A light adjusting sheet for a planar light device according to claim 1, wherein opposite to said one surface is another surface which is non-optically flat.
Claim 4
Dependent Claim
23 words
A light adjusting sheet for a planar lighting device according to claim 2: wherein said non-optically flat surface is a fine uneven surface.
Claim 5
Dependent Claim
33 words
A light adjusting sheet for a planar lighting device according to claim 3: wherein said fine uneven surface is formed by either the mat treatment method, the sand-blasting method or the press method.
Claim 6
Dependent Claim
22 words
A light adjusting sheet for a planar lighting device according to claim 2: wherein said non-optically flat surface has a triangular cross-section.
Claim 7
Dependent Claim
34 words
A light adjusting sheet for a planar lighting device according to claim 2: wherein another surface opposite to said one surface is made into a non-optically flat surface which is a moderate wave-form surface.
Claim 8
Dependent Claim
162 words
A light adjusting sheet for a planar lighting device which is placed at the front of a light emitting surface of a light guiding plate which composes said planar lighting device comprising: a plurality of convex regions each having a lateral cross section of a convex arc on one surface; and a plurality of concave regions each having a lateral cross section of a concave arc on said one surface; wherein each convex region and each concave region are arranged alternately and approximately parallel to each other; said plurality of convex regions and concave regions having a cross-section of a sine curve represented by an equation Y=a·sin bX (1) wherein Y=coordinate in the depth-wise direction in μm units; X=coordinate in the lateral direction in μm units; "a"=factor in the range of 15 to 1500 in μm units; "b"=factor in the range of 0.005 to 1 in degree/μm units; and an average sheet thickness is in the range of 0.01 to 3 mm.
Claim 9
Dependent Claim
162 words
A light adjusting sheet for a planar lighting device which is placed at the front of a light emitting surface of a light guiding plate which composes said planar lighting device comprising: a plurality of convex regions each having a lateral cross section of a convex arc on one surface; and a plurality of concave regions each having a lateral cross section of a concave arc on said one surface; wherein each convex region and each concave region are arranged alternately and approximately parallel to each other; said plurality of convex regions and concave regions having a cross-section of a sine curve represented by an equation Y=a·sin bX (1) wherein Y=coordinate in the depth-wise direction in μm units; X=coordinate in the lateral direction in μm units; "a"=factor in the range of 15 to 1500 in μm units; "b"=factor in the range of 0.005 to 1 in degree/μm units; and an average sheet thickness is in the range of 0.01 to 3 mm.
Claim 10
Dependent Claim
174 words
A light adjusting sheet for a planar lighting device which is placed at the front of a light emitting surface of a light guiding plate which composes said planar lighting device comprising: a plurality of convex regions each having a lateral cross-section of a convex arc on one surface; and a plurality of concave regions each having a lateral cross-section of a concave arc on said one surface; wherein each convex region and each concave region are arranged alternately and approximately parallel to each other; said plurality of convex regions and concave regions having a cross-section of a sine curve represented by an equation Y=a·sin bX (1) wherein Y=coordinate in the depth-wise direction in μm units; X=coordinate in the lateral direction in μm units; "a"=factor in the range of 15 to 1500 in μm units; "b"=factor in the range of 0.005 to 1 in degree/μm units; another surface opposite to said one surface is made into a non-optically flat surface; and an average sheet thickness is in the range of 0.01 to 3 mm.
Claim 11
Dependent Claim
174 words
A light adjusting sheet for a planar lighting device which is placed at the front of a light emitting surface of a light guiding plate which composes said planar lighting device comprising: a plurality of convex regions each having a lateral cross-section of a convex arc on one surface; and a plurality of concave regions each having a lateral cross-section of a concave arc on said one surface; wherein each convex region and each concave region are arranged alternately and approximately parallel to each other; said plurality of convex regions and concave regions having a cross-section of a sine curve represented by an equation Y=a·sin bX (1) wherein Y=coordinate in the depth-wise direction in μm units; X=coordinate in the lateral direction in μm units; "a"=factor in the range of 15 to 1500 in μm units; "b"=factor in the range of 0.005 to 1 in degree/μm units; another surface opposite to said one surface is made into a non-optically flat surface; and an average sheet thickness is in the range of 0.01 to 3 mm.
Claim 12
Dependent Claim
23 words
A light adjusting sheet for a planar lighting device according to claim 8: wherein said non optically-flat surface is a fine uneven surface.
Claim 13
Dependent Claim
34 words
A light adjusting sheet for a planar lighting device according to claim 9: wherein said fine uneven surface is formed by either the mat treatment method, the sand blasting method or the press method.
Claim 14
Dependent Claim
23 words
A light adjusting sheet for a planar lighting device according to claim 8: wherein said non optically-flat surface has a triangular cross section.
Claim 15
Dependent Claim
23 words
A light adjusting sheet for a planar lighting device according to claim 8: wherein said non optically-flat surface is a moderate wave-form surface.
Claim 16
Dependent Claim
23 words
A light adjusting sheet for a planar lighting device according to claim 8: wherein said light adjusting sheet contains a light diffusing material.
Claim 17
Dependent Claim
193 words
A planar lighting device comprising: a light guiding plate having a dot pattern on a back surface; a linear light source placed on at least one side of said light guiding plate; a reflector plate placed in back of said light guiding plate; and a light adjusting sheet placed at the front of a light emitting surface of said light guiding plate, having on one surface a plurality of convex regions each having a lateral cross section of a convex arc and also on said one surface a plurality of concave regions each having a lateral cross section of a concave arc; wherein each convex region and each concave region are arranged alternately and approximately parallel to each other; adjacent concave and convex regions being connected by a flat surface having an area equal to or less than 50% of the total area of the curved surfaces; another surface opposite to said one surface having a non-optical flat surface; and peak lines of said convex regions and bottom lines of said concave regions of said light adjusting sheet being arranged to make a predetermined angle with an axis of said linear light source.
Claim 18
Dependent Claim
193 words
A planar lighting device comprising: a light guiding plate having a dot pattern on a back surface; a linear light source placed on at least one side of said light guiding plate; a reflector plate placed in back of said light guiding plate; and a light adjusting sheet placed at the front of a light emitting surface of said light guiding plate, having on one surface a plurality of convex regions each having a lateral cross section of a convex arc and also on said one surface a plurality of concave regions each having a lateral cross section of a concave arc; wherein each convex region and each concave region are arranged alternately and approximately parallel to each other; adjacent concave and convex regions being connected by a flat surface having an area equal to or less than 50% of the total area of the curved surfaces; another surface opposite to said one surface having a non-optical flat surface; and peak lines of said convex regions and bottom lines of said concave regions of said light adjusting sheet being arranged to make a predetermined angle with an axis of said linear light source.
Claim 19
Dependent Claim
212 words
A planar lighting device comprising: a light guiding plate having a dot pattern on a back surface; a linear light source placed on at least one side of said light guiding plate; a reflector plate placed in back of said light guiding plate; and a light adjusting sheet placed at the front of a light emitting surface of said light guiding plate, having on one surface a plurality of convex regions each having a lateral cross section of a convex arc and also on said one surface a plurality of concave regions each having a lateral cross section of a concave arc; wherein each convex region and each concave region are arranged alternately and approximately parallel to each other; said plurality of convex regions and concave regions having a cross-section of a sine curve represented by an equation Y=a·sin bX (1) wherein Y=coordinate in the depth-wise direction in μm units; X=coordinate in the lateral direction in μm units; "a"=factor in μm units; "b"=factor in degree/μm units; another surface opposite to said one surface having a non-optical flat surface; and peak lines of said convex regions and bottom lines of said concave regions of said light adjusting sheet being arranged to made a predetermined angle with an axis of said linear light source.
Claim 20
Dependent Claim
212 words
A planar lighting device comprising: a light guiding plate having a dot pattern on a back surface; a linear light source placed on at least one side of said light guiding plate; a reflector plate placed in back of said light guiding plate; and a light adjusting sheet placed at the front of a light emitting surface of said light guiding plate, having on one surface a plurality of convex regions each having a lateral cross section of a convex arc and also on said one surface a plurality of concave regions each having a lateral cross section of a concave arc; wherein each convex region and each concave region are arranged alternately and approximately parallel to each other; said plurality of convex regions and concave regions having a cross-section of a sine curve represented by an equation Y=a·sin bX (1) wherein Y=coordinate in the depth-wise direction in μm units; X=coordinate in the lateral direction in μm units; "a"=factor in μm units; "b"=factor in degree/μm units; another surface opposite to said one surface having a non-optical flat surface; and peak lines of said convex regions and bottom lines of said concave regions of said light adjusting sheet being arranged to made a predetermined angle with an axis of said linear light source.
Claim 21
Dependent Claim
205 words
A liquid crystal display comprising: a light guiding plate having a dot pattern on a back surface; a liquid crystal display element being forward of said light guiding plate; a linear light source placed on at least one side of said light guiding plate; a reflector plate placed in back of said light guiding plate; and a light adjusting sheet placed at the front of a light emitting surface of said light guiding plate, having on one surface a plurality of convex regions each having a lateral cross section of a convex arc and also on said one surface a plurality of concave regions each having a lateral cross section of a concave arc; wherein each convex region and each concave region are arranged alternately and approximately parallel to each other; adjacent concave and convex regions being connected by a flat surface having an area equal to or less than 50% of the total area of the curved surfaces; another surface opposite to said one surface having a non-optical flat surface; and peak lines of said convex regions and bottom lines of said concave regions of said light adjusting sheet being arranged to make a predetermined angle with an axis of said linear light source.
Claim 22
Dependent Claim
205 words
A liquid crystal display comprising: a light guiding plate having a dot pattern on a back surface; a liquid crystal display element being forward of said light guiding plate; a linear light source placed on at least one side of said light guiding plate; a reflector plate placed in back of said light guiding plate; and a light adjusting sheet placed at the front of a light emitting surface of said light guiding plate, having on one surface a plurality of convex regions each having a lateral cross section of a convex arc and also on said one surface a plurality of concave regions each having a lateral cross section of a concave arc; wherein each convex region and each concave region are arranged alternately and approximately parallel to each other; adjacent concave and convex regions being connected by a flat surface having an area equal to or less than 50% of the total area of the curved surfaces; another surface opposite to said one surface having a non-optical flat surface; and peak lines of said convex regions and bottom lines of said concave regions of said light adjusting sheet being arranged to make a predetermined angle with an axis of said linear light source.
Claim 23
Dependent Claim
224 words
A liquid crystal display comprising: a light guiding plate having a dot pattern on a back surface; a liquid crystal display element being forward of said light guiding plate; a linear light source placed on at least one side of said light guiding plate; a reflector plate placed in back of said light guiding plate; and a light adjusting sheet placed at the front of a light emitting surface of said light guiding plate, having on one surface a plurality of convex regions each having a lateral cross section of a convex arc and also on said one surface a plurality of concave regions each having a lateral cross section of a concave arc; wherein each convex region and each concave region are arranged alternately and approximately parallel to each other; said plurality of convex regions and concave regions having a cross-section of a sine curve represented by an equation Y=a·sin bX (1) wherein Y=coordinate in the depth-wise direction in μm units; X=coordinate in the lateral direction in μm units; "a"=factor in μm units; "b"=factor in degree/μm units; another surface opposite to said one surface having a non-optical flat surface; and peak lines of said convex regions and bottom lines of said concave regions of said light adjusting sheet being arranged to made a predetermined angle with an axis of said linear light source.
Claim 24
Dependent Claim
224 words
A liquid crystal display comprising: a light guiding plate having a dot pattern on a back surface; a liquid crystal display element being forward of said light guiding plate; a linear light source placed on at least one side of said light guiding plate; a reflector plate placed in back of said light guiding plate; and a light adjusting sheet placed at the front of a light emitting surface of said light guiding plate, having on one surface a plurality of convex regions each having a lateral cross section of a convex arc and also on said one surface a plurality of concave regions each having a lateral cross section of a concave arc; wherein each convex region and each concave region are arranged alternately and approximately parallel to each other; said plurality of convex regions and concave regions having a cross-section of a sine curve represented by an equation Y=a·sin bX (1) wherein Y=coordinate in the depth-wise direction in μm units; X=coordinate in the lateral direction in μm units; "a"=factor in μm units; "b"=factor in degree/μm units; another surface opposite to said one surface having a non-optical flat surface; and peak lines of said convex regions and bottom lines of said concave regions of said light adjusting sheet being arranged to made a predetermined angle with an axis of said linear light source.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-09-03 | 2000-03-04 | 2000-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-09-03 | 2004-03-04 | 2004-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-09-03 | 2008-03-04 | 2008-09-03 | $7700.00 | Window Closed / Lapsed |