EP0219480A2
Expired / Lapsed
EP
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Ferroelectric liquid crystal devices
Assignee: Sarl S T LAGERWALL
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Filing: 1986-10-14
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Granted: —
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Expires: 2006-10-14
Abstract
Abstract Practical devices for the application of surface-stabilized ferroelectric liquid crystals are described which use no polarizing filter, or only one polarizing filter. One embodiment comprises a quarter-wave plate (502) as an optically active layer between the ferroelectric liquid crystal layer (501) and the reflective surface (503).
Inventors
- 👤 Sven T. Lagerwall
- 👤 Gengt Stebler
- 👤 Jürgen Wahl
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-25 08:50
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/137; G02F1/13725; G02F1/133; G02F1/1333; G02F1/1335; G02F1/133528; G02F1/139; G02F1/141; G02F1/13363; G02F1/133638; G02F2203/00; G02F2203/02
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
45 words
A liquid crystal device having a liquid crystal layer confined between two surfaces and selectably switchable by electrical means between two polarization states, a reflexion surface, an optically active layer between said reflexion surface and the liquid crystal layer, and a layer having dichroic properties.
Claim 2
Dependent Claim
45 words
A liquid crystal device having a liquid crystal layer confined between two surfaces and selectably switchable by electrical means between two polarization states, a reflexion surface, an optically active layer between said reflexion surface and the liquid crystal layer, and a layer having dichroic properties.
Claim 3
Dependent Claim
15 words
A device of claim 1, wherein said layer having dichroic properties is a polarizer layer.
Claim 4
Dependent Claim
38 words
A device of claim 1, wherein said layer having dichroic properties is the liquid crystal layer, wherein a dichroic substance is admixed, having the property of being direction controlled by the switchable matter of the liquid crystal layer.
Claim 5
Independent Claim
20 words
A device of a preceding claim, wherein said liquid crystal has its two polarization states rotationally displaced by about 45°C.
Claim 6
Independent Claim
18 words
A device of a preceding claim, wherein said optically acitve layer is a layer having quarter-wave plate properties.
Claim 7
Independent Claim
16 words
A device of a preceding claim, wherein said optically active layer is made of stretched cellophane.
Claim 8
Dependent Claim
31 words
A device of claim 3, wherein said direction controlled dichroic substance is being continuously switched back and forth and the resulting light scattering is being utilized without the use of polarizers.
References Cited (Backward Citations)
No citation records indexed.
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