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EP0311405A2
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A liquid-crystal display device
Assignee: Sharp Corp
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Filing: 1988-10-06
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Granted: —
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Expires: 2008-10-06
Abstract
Abstract A liquid-crystal display device comprises a multi-layered-type liquid-crystal cell that is composed of at least first and second cell layers (C₁, C₂), the cell containing liquid-crystal molecules with a twisted nematic orientation therein. The angle of twist of the liquid-crystal molecules in the first cell layer (C₁) is opposite to that of twist of the liquid-crystal molecules in the second cell layer (C₂). The orientation of the liquid-crystal molecules in the first cell layer (C₁) in the vicinity of the second cell layer is at an angle of 70° to 150° to that of the liquid-crystal molecules in the second cell layer (C₂) in the vicinity of the first cell layer (G₁). The first cell layer (C₁) has a voltage-applying means that changes the orientation of the liquid-crystal molecules therein and the second cell (C₂) layer is a cell layer that does not change the orientation of the liquid-crystal molecules therein.
Inventors
- 👤 Naofumi Kimura
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 16:45
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1347; G02F1/13471; G02F1/1335; G02F1/13363; G02F1/133636; G02F1/137; G02F1/139; G02F1/1396; G02F1/1397
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
156 words
A liquid-crystal display device comprising a multi-layered-type liquid-crystal cell that is composed of at least first and second cell layers (C₁, C₂), said cell containing liquid-crystal molecules with a twisted nematic orientation therein, characterised in that the angle of twist of the liquid-crystal molecules in the first cell layer (C₁) is opposite to that of the twist of the liquid-crystal molecules in the second cell layer (C₂), the orientation of the liquid-crystal molecules in the first cell layer (C₁) in the vicinity of the second cell layer (C₂) is at an angle of 70° to 150° to that of the liquid-crystal molecules in the second cell layer (C₂) in the vicinity of the first cell layer (C₁), the first cell layer (C₁) has a voltage-applying means that changes the orientation of the liquid-crystal molecules therein and the second cell layer (C₂) is a cell layer that does not change the orientation of the liquid-crystal molecules therein.
Claim 2
Dependent Claim
156 words
A liquid-crystal display device comprising a multi-layered-type liquid-crystal cell that is composed of at least first and second cell layers (C₁, C₂), said cell containing liquid-crystal molecules with a twisted nematic orientation therein, characterised in that the angle of twist of the liquid-crystal molecules in the first cell layer (C₁) is opposite to that of the twist of the liquid-crystal molecules in the second cell layer (C₂), the orientation of the liquid-crystal molecules in the first cell layer (C₁) in the vicinity of the second cell layer (C₂) is at an angle of 70° to 150° to that of the liquid-crystal molecules in the second cell layer (C₂) in the vicinity of the first cell layer (C₁), the first cell layer (C₁) has a voltage-applying means that changes the orientation of the liquid-crystal molecules therein and the second cell layer (C₂) is a cell layer that does not change the orientation of the liquid-crystal molecules therein.
Claim 3
Dependent Claim
63 words
A liquid-crystal display device according to claim 1, wherein the orientation of the liquid-crystal molecules in the first cell layer (C₁) in the vicinity of the second cell layer (C₂) is at an angle of 70° to 80° or 110° to 150° to that of the liquid-crystal molecules in the second cell layer (C₂) in the vicinity of the first cell layer (C₁).
Claim 4
Dependent Claim
59 words
A liquid-crystal display device according to claim 2, wherein the orientation of the liquid-crystal molecules in the first cell layer (C₁) in the vicinity of the second cell layer (C₂) is at an angle of 120° to 150° to that of the liquid-crystal molecules in the second cell (C₂) layer in the vicinity of the first cell layer (C₁).
Claim 5
Dependent Claim
39 words
A liquid-crystal display device according to claim 1, 2, or 3, wherein the angle of twist of the liquid-crystal molecules in each of the first and second cell layers (C₁, C₂) is in the range of 180° to 360°.
Claim 6
Dependent Claim
87 words
A liquid-crystal display device according to claim 1, wherein the angles of twist of the liquid-crystal molecules in the first and second cell layers (C₁, C₂) are nearly equal to each other, and the product Δn₁·d₁ of the birefringence Δn₁ and the thickness d₁ of the liquid-crystal layer in the first cell layer (C₁) and the product Δn₂·d₂ of the birefringence Δn₂ and the thickness d₂ of the liquid-crystal layer in the second cell layer (C₂) are represented by the following inequality : 0.7·Δn₂·d₂ < Δn₁·d₁ <1.4·Δn₂·d₂
Claim 7
Dependent Claim
67 words
A liquid-crystal display device according to claim 1, wherein the relationship between the pitch p of twist of the liquid-crystal molecules in the cell layer (C₁) that has the voltage-applying means therein and the thickness d of the liquid-crystal layer in the said cell layer (C₁) is as follows ϑ/2π - 1/4 < d/p ≲ ϑ/2π wherein ϑ is the angle of twist of the liquid-crystal molecules.
Claim 8
Dependent Claim
34 words
A liquid-crystal display device according to any one the preceding claims 1 to 6, wherein a colour filter layer is disposed in at least one of the first and second cell layers (C₁, C₂).
Claim 9
Dependent Claim
38 words
A liquid-crystal display device according to any one of the preceding claims 1 to 7, wherein an active device is disposed on each picture element in at least one of the first and second cell layers (C₁, C₂).
References Cited (Backward Citations)
No citation records indexed.
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