Patent EP0338675A1 successfully refreshed from Google Patents.
EP0338675A1
Expired / Lapsed
EP
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Analogue modulation of light
Assignee: STC PLC
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Filing: 1989-03-16
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Granted: —
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Expires: 2009-03-16
Abstract
Abstract An analogue optical response is provided in a planar aligned inclined smectic phase liquid crystal cell by the application of an amplitude modulated oscillatory potential across the thickness of the liquid crystal layer.
Inventors
- 👤 Matthew Francis Bone
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 21:01
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/137; G02F1/139; G02F1/141
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
55 words
A method of impressing modulation upon a beam of light wherein the light is directed through a planar aligned inclined smectic phase liquid crystal layer confined between two surfaces, characterised in that amplitude modulation of the beam of light is impressed by the maintenance of an amplitude modulated oscillatory potential across said liquid crystal layer.
Claim 2
Independent Claim
55 words
A method of impressing modulation upon a beam of light wherein the light is directed through a planar aligned inclined smectic phase liquid crystal layer confined between two surfaces, characterised in that amplitude modulation of the beam of light is impressed by the maintenance of an amplitude modulated oscillatory potential across said liquid crystal layer.
Claim 3
Dependent Claim
18 words
A method as claimed in claim 1, wherein the liquid crystal layer is in the smectic C phase.,
Claim 4
Dependent Claim
16 words
A method as claimed in claim 1 or 2 wherein the liquid crystal layer is ferroelectric.
Claim 5
Dependent Claim
18 words
A method as claimed in claim 1 or 2 wherein the liquid crystal layer is a racemic mixture.
Claim 6
Dependent Claim
66 words
A method as claimed in claim 3 wherein the frequency of the oscillatory potential is sufficiently high in relation to the frequency of its amplitude modulation to make the response of the liquid crystal layer to the applied potential resulting from interaction with the ferroelectric dipole of the liquid crystal insignificant compared with the response resulting from interaction with the induced dipole of the liquid crystal.
Claim 7
Independent Claim
24 words
A method as claimed in any preceding claim wherein the two surfaces between which the liquid crystal layer is confined are rubbed polymer surfaces.
References Cited (Backward Citations)
DE3630012A1
Cited
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