EP0320283A2
Expired / Lapsed
EP
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Electro-optical device
Assignee: Seiko Epson Corp
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Filing: 1988-12-09
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Granted: —
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Expires: 2008-12-09
Abstract
Abstract An electro-optical device, which can be used as a field effect type display, comprises an upper polariser (1), a first liquid crystal cell (2), a second liquid cell (3) for providing a display, and a lower polariser (4). The first liquid crystal cell acts as an optically anisotropic medium. The second liquid crystal cell includes transparent electrodes (13) which face each other. The optically anisotropic medium differs from the second liquid crystal cell in at least one of refractive index dispersion, refractive index anisotropy, and layer thickness.
Inventors
- 👤 Hiroshi Wada
- 👤 Chiyoaki Iijima
- 👤 Hiroshi Ohara
- 👤 Yoichi Momose
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 19:48
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/13363; G02F1/133636; G02F1/1347; G02F1/13471; G02F1/137; G02F1/139; G02F1/1396; G02F1/1397
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
75 words
An electro-optical device comprising: a liquid crystal cell (3), the liquid crystal cell having a liquid crystal layer (6) and means (13) for applying a voltage to at least a part of the liquid crystal layer, and an optically anisotropic medium (2) characterised in that the optically anisotropic medium differs from the liquid crystal cell in at least one of refractive index dispersion (α), refractive index anisotropy ( Δn), thickness layer (d), and twist angle.
Claim 2
Dependent Claim
75 words
An electro-optical device comprising: a liquid crystal cell (3), the liquid crystal cell having a liquid crystal layer (6) and means (13) for applying a voltage to at least a part of the liquid crystal layer, and an optically anisotropic medium (2) characterised in that the optically anisotropic medium differs from the liquid crystal cell in at least one of refractive index dispersion (α), refractive index anisotropy ( Δn), thickness layer (d), and twist angle.
Claim 3
Dependent Claim
21 words
An electro-optical device as claimed in claim 1, characterised in that the liquid crystal cell comprises a nematic liquid crystal material.
Claim 4
Dependent Claim
28 words
An electro-optical device as claimed in claim 2, characterised in that the liquid crystal material has a twist angle that lies in the range from 90° to 360°.
Claim 5
Dependent Claim
25 words
An electro-optical device as claimed in claim 1, 2 or 3 characterised in that the optically anisotropic medium comprises a nematic liquid crystal material (5).
Claim 6
Dependent Claim
33 words
An electro-optical device as claimed in claim 4, characterised in that the liquid crystal material of the optically anisotropic medium has a twist angle that lies in the range from 0° to 400°.
Claim 7
Dependent Claim
40 words
An electro-optical device as claimed in claim 4 or 5 characterised in that the liquid crystal material of the optically anisotropic medium has a layer thickness exceeding the layer thickness of the liquid crystal material of the liquid crystal cell.
Claim 8
Dependent Claim
63 words
An electro-optical device as claimed in claim 1, characterised in that the product of the refractive index anisotropy ( Δ n) and the layer thickness (d) of the liquid crystal material of the optically anisotropic medium is less than the product of the refractive index anisotropy (Δ n) and the layer thickness (d) of the liquid crystal material of the liquid crystal cell.
Claim 9
Dependent Claim
73 words
An electro-optical device comprising: a liquid crystal cell (3), the liquid crystal cell having a liquid crystal layer (6) and means (13) for applying a voltage to at least a part of the liquid crystal layer, and an optically anisotropic medium (2), characterised in that the optically anisotropic mediun differs from the liquid crystal cell in at least one of refractive index dispersion (α), refractive index anisotropy (Δ n), and layer thickness (d).
Claim 10
Dependent Claim
73 words
An electro-optical device comprising: a liquid crystal cell (3), the liquid crystal cell having a liquid crystal layer (6) and means (13) for applying a voltage to at least a part of the liquid crystal layer, and an optically anisotropic medium (2), characterised in that the optically anisotropic mediun differs from the liquid crystal cell in at least one of refractive index dispersion (α), refractive index anisotropy (Δ n), and layer thickness (d).
References Cited (Backward Citations)
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