EP0284372A2
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EP
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A liquid-crystal display device
Assignee: Sharp Corp
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Filing: 1988-03-23
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Granted: —
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Expires: 2008-03-23
Abstract
Abstract A liquid-crystal display device comprising a double-layered-type liquid-crystal cell that is composed of a first cell layer (C₁) and a second cell layer (C₂), said cell containing liquid-crystal molecules (4) with a twisted nematic orientation therein and a voltage-applying means (2, 22, 32) in one of the first and second cell layers (C₁), wherein the angle of twist of the liquid-crystal molecules (4) in the first cell layer (C₁) is opposite to that of twist of the liquid-crystal molecules (4) in the second cell layer (C₂), and the orientation of the liquid-crystal molecules (4) in the first cell layer (C₁) in the vicinity of the second cell layer (C₂) is at right angles to that of the liquid-crystal molecules (4) in the second cell layer (C₂) in the vicinity of the first cell layer (C₁).
Inventors
- 👤 Naofumi Kimura
- 👤 Yutaka Ishii
- 👤 Shuichi Kozaki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 20:16
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1347; G02F1/13471; G02F1/137; G02F1/139; G02F1/1396; G02F1/1397
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
133 words
A liquid-crystal display device comprising: a double-layered type liquid-crystal cell that is composed of a first cell layer (C₁) and a second cell layer (C₂), said cell containing liquid-crystal molecules with a twisted nematic orientation therein and a voltage-applying means (2, 22, 32) in one of the first and second cell layers (C₁). wherein the angle of twist of the liquid-crystal molecules (4) in the first cell layer (C₁) is opposite to that of twist of the liquid-crystal molecules in the second cell layer (C₂), and the orientation of the liquid-crystal molecules (4) in the first cell layer (C₁) in the vicinity of the second cell layer (C₂) is at right angles to that of the liquid-crystal molecules in the second cell layer (C₂) in the vicinity of the first cell layer (C₁).
Claim 2
Dependent Claim
133 words
A liquid-crystal display device comprising: a double-layered type liquid-crystal cell that is composed of a first cell layer (C₁) and a second cell layer (C₂), said cell containing liquid-crystal molecules with a twisted nematic orientation therein and a voltage-applying means (2, 22, 32) in one of the first and second cell layers (C₁). wherein the angle of twist of the liquid-crystal molecules (4) in the first cell layer (C₁) is opposite to that of twist of the liquid-crystal molecules in the second cell layer (C₂), and the orientation of the liquid-crystal molecules (4) in the first cell layer (C₁) in the vicinity of the second cell layer (C₂) is at right angles to that of the liquid-crystal molecules in the second cell layer (C₂) in the vicinity of the first cell layer (C₁).
Claim 3
Dependent Claim
66 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 products Δn'd of the birefringence Δn and the thickness d of the liquid-crystal layers (4) in each of the first and second cell layers (C₁, C₂) are nearly equal to each other.
Claim 4
Dependent Claim
107 words
A liquid-crystal display device according to claim 1, wherein the angles of twist of the liquid-crystal molecules (4) 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 one of the first and second cell layers (C₁) that undergoes an optical change because of an external force and the product Δn₂,d₂ of the birefringence Δn₂ and the thickness d₂ of the liquid-crystal layer in the other cell layer (c₂) that does not undergo an optical change are represented by the following inequality: Δn₂.d₂ < 0.85Δn₁.d₁
Claim 5
Dependent Claim
40 words
A liquid-crystal display device according to claim 1, 2, or 3, wherein the angle of twist of the liquid-crystal molecules (4) in each of the first and second cell layers (C₁, C₂) is in the range of 180° to 360°.
Claim 6
Dependent Claim
64 words
A liquid-crystal display device according to claim 1, wherein the relationship between the pitch p of twist of the liquid-crystal molecules (4) in the cell layers (C₁) that has the voltage-applying means therein and the thickness d of the liquid-crystal layer in the same 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 (4).
Claim 7
Dependent Claim
31 words
A liquid-crystal display device according to any one of the preceding claims 1-5, wherein a color filter layer is disposed in at least one of the first and second cell layers.
Claim 8
Dependent Claim
34 words
A liquid-crystal display device according to any one of the preceding claims 1-6, wherein an active device is disposed on each picture element in at least one of the first and second cell layers.
References Cited (Backward Citations)
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