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US4488786A Expired / Lapsed US ⏱️ 0.0 years remaining

Electro-optical display element for preventing specular reflection of incident light

Assignee: Mannesmann VDO AG
•
Filing: 1981-04-30
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Granted: 1984-12-18
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Expires: 2001-04-30
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Abstract

Abstract A passive electro-optical display element for the representation of information, having two glass plates spaced apart from each other and forming a chamber therebetween, on the chamber side of each plate there being provided a transparent electrode support and the chamber being filled with a liquid-crystal substance, while polarizers are arranged on the outer surfaces of the plates. The surface of the polarizer on the viewing side of the display element facing the observer and away from the glass plate is formed with a plurality of depressions of irregular structure. A reflector is disposed on the polarizer at the opposite side of the display element.

Inventors

  • 👤 Rudolf Caramel

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 19:20
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/133528

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 140 words
A passive electro-optical display element for the representation of information, having two glass plates spaced apart from each other and forming a chamber therebetween, on the chamber side of each plate there being provided a transparent electrode support and the chamber being filled with a liquid-crystal substance, and wherein polarizers are disposed on the outer surfaces of said plates respectively, the improvement wherein one of the polarizers on a viewing side of the display element has a front surface facing away from the corresponding glass plate, said front surface being formed with a plurality of depressions of irregular structure for scattering light incident upon said front surface from said viewing side to prevent specular reflection of such light, and wherein a reflecter is disposed on the other polarizer at the side remote from the viewing side of the display element.
Claim 2
Dependent Claim 140 words
A passive electro-optical display element for the representation of information, having two glass plates spaced apart from each other and forming a chamber therebetween, on the chamber side of each plate there being provided a transparent electrode support and the chamber being filled with a liquid-crystal substance, and wherein polarizers are disposed on the outer surfaces of said plates respectively, the improvement wherein one of the polarizers on a viewing side of the display element has a front surface facing away from the corresponding glass plate, said front surface being formed with a plurality of depressions of irregular structure for scattering light incident upon said front surface from said viewing side to prevent specular reflection of such light, and wherein a reflecter is disposed on the other polarizer at the side remote from the viewing side of the display element.
Claim 3
Dependent Claim 15 words
The display element according to claim 1 wherein said depressions have a substantially semi-spherical cross-section.
Claim 4
Dependent Claim 15 words
The display element according to claim 1 wherein said depressions have a substantially pyramidal cross-section.
Claim 5
Dependent Claim 12 words
The display element according to claim 1 wherein said depressions are embossed.

References Cited (Backward Citations)

US3709580A Cited
US3806227A Cited
US4106859A Cited
US4264147A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-12-18 1988-06-18 1988-12-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-12-18 1992-06-18 1992-12-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-12-18 1996-06-18 1996-12-18 $7700.00 Window Closed / Lapsed

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