Patent EP0632229A1 successfully refreshed from Google Patents.
EP0632229A1
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Plane light source unit
Assignee: Mitsubishi Chemical Corp
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Filing: 1993-06-28
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Granted: —
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Expires: 2013-06-28
Abstract
Abstract A plane light source unit which may be advantageously used as a backlighting means for a liquid crystal display device, and which comprises a transparent light guide (1) having a side end surface (7) as a light incident surface, a surface (6) perpendicular to the light incident surface as a light emitting surface, and a light reflecting layer (2) provided on an opposite surface (9) to the light emitting surface (6); and a second element (3) having a large number of prism units formed on the light emitting surface (6) of the transparent light guide (1) which receives the light emitted from the transparent light guide (1) and emits the light in a predetermined direction; wherein at least one of the light emitting surface (6) and the opposite surface (9) of said transparent light guide (1) has a directional light emitting function which emits the incident light from the light incident surface (7) of the transparent light guide (1) in an oblique direction to the incident light and has a regulation function which makes the luminance of the light through the light emitting surface (6) uniform over the whole surface thereof.
Inventors
- 👤 Oe C/O Tokyo Res. Lab. Maketo
- 👤 Issei C/O Tokyo Res. Lab. Chiba
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 10:46
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/0001; G02B6/0011; G02B6/0033; G02B6/0058; G02B6/0061; G02B6/0035; G02B6/0036; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/1336; G02F1/133615; G02B6/0038; G02B6/004; G02B6/005; G02B6/0053
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
148 words
A plane light source unit comprising a transparent light guide having a side end surface as a light-incident surface, a surface perpendicular to the light-incident surface as a light-emitting surface, and a light-reflecting layer provided on an opposite surface to the light-emitting surface; and a second element having a large number of prism units formed on the light-emitting surface of the transparent light guide which receives the light emitted from the transparent light guide and emits the light in a predetermined direction; wherein at least one of the light-emitting surface and the opposite surface of the transparent light guide has a directional light-emitting function which emits the incident light from the light-incident surface of the transparent light guide in an oblique direction to the incident light and has a regulation function which makes the luminance of the light through the light-emitting surface uniform over the whole surface thereof.
Claim 2
Dependent Claim
104 words
A plane light source unit as claimed in claim 1; wherein the transparent light guide has a roughened light-emitting surface having a directional light-emitting function, a light-incident surface provided on at least one side of the side end surfaces thereof, and a light-reflecting layer provided on the opposite surface to the light-emitting surface; and said roughened light-emitting surface having flat areas so that the ratio of the flat areas thereon increses as the distance from the light-incident surface decreases, whereby the transparent light guide regulates the luminance of the light so as to be uniform through the light-emitting surface over the whole surface thereof.
Claim 3
Dependent Claim
117 words
A plane light source unit as claimed in claim 1, wherein the transparent light guide has a light-emitting surface, a light incident surface provided on at least one of the side end surfaces thereof, a roughened surface having a directional light emitting function opposite to the light emitting surface, and a light reflecting layer provided on the opposite surface to the light emitting surface; and the roughened opposite surface having flat areas so that the ratio of the flat areas thereon increases as the distance from the light incident surface decreases, whereby the transparent light guide regulates the luminance of the light so as to be uniform through the light emitting surface over the whole surface thereof.
Claim 4
Dependent Claim
32 words
A plane light source unit as claimed in claim 2 or claim 3, wherein the haze value of the roughened surface formed on the transparent light guide is not less than 30%.
Claim 5
Dependent Claim
124 words
A plane light source unit as claimed in claim 1; wherein the transparent light guide has a light emitting surface comprising a plurality of lens units each of which has a directional light emitting function, a light incident surface provided on at least one of the side and surfaces thereof, and a light reflecting layer provided on the opposite surface to the light emitting surface; and the light emitting surface comprising a plurality of lens units having flat areas so that the ratio of the flat areas thereon increase as the distance from the light incident surface decreases, whereby the transparent light guide regulates the luminance of the light so as to be uniform through the light emitting surface over the whole surface thereof.
Claim 6
Dependent Claim
127 words
A plane light source unit as claimed in claim 1; wherein the transparent light guide has a light emitting surface, a light incident surface provided on at least one of the side end surfaces thereof, a surface opposite to the light emitting surface comprising a plurality of lens units each of which has a directional light emitting function, and a light reflecting layer provided on the opposite surface; and the light emitting surface comprising a plurality of lens units has flat areas so that the ratio of the flat areas thereon increases as the distance from the light incident surface decreases, whereby the transparent light guide regulates the luminance of the light so as to be uniform through the light emitting surface over the whole surface thereof.
Claim 7
Dependent Claim
22 words
A plane light source unit as claimed in any one preceding claim wherein the transparent light guide is produced by injection molding.
Claim 8
Dependent Claim
21 words
A plane light source unit as claimed in any one preceding claim, wherein the transparent light guide comprises an acrylic resin.
References Cited (Backward Citations)
US5126882A
Cited
EP0500960A1
Cited
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