Claims
- 1. A liquid crystal display capable of displaying an image to a viewer, the display comprising:a pair of electrodes sandwiching a liquid crystal layer therebetween, said pair of electrodes for applying a voltage across said liquid crystal layer; first and second polarizers sandwiching said liquid crystal layer therebetween; first and second orientation layers disposed adjacent said liquid crystal layer on opposite sides thereof, said first and second orientation layers for aligning liquid crystal molecules of said liquid crystal layer; first and second negative biaxial retardation members, wherein each of said first and second negative biaxial retardation members has a retardation value d.ΔnZY of from about −10 to −100 nm where “d” is the thickness of the retardation member; and wherein at least a portion of each of said first and second negative biaxial retardation members has indices of refraction nx, ny, and nz where nz is oriented in a direction perpendicular to nx and ny.
- 2. A liquid crystal display for displaying an image to a viewer, the liquid crystal display comprising:a liquid crystal layer disposed between first and second electrodes, said first and second electrodes for applying a voltage across said liquid crystal layer; first and second polarizers, said liquid crystal layer being located between said first and second polarizers; first and second orientation layers, said liquid crystal layer being located between said first and second orientation layers; first and second negative retarders located on opposite sides of said liquid crystal layer so that said liquid crystal layer is disposed between said first and second negative retarders, each of said first and second negative retarders including three different and unequal indices of refraction; wherein each of said negative retarders includes a retardation value d.ΔZY of from about −10 to −100 nm, where the retardation value is defined by the thickness of the retarder multiplied by a difference between two of said three indices of refraction; and wherein said retarders are so arranged with respect to one another so that the display can achieve a white light contrast ratio of at least about 10:1 over a horizontal viewing angular span, at a predetermined vertical viewing angle, of at least about 120°, and over a vertical viewing angular span of greater than about 60° at a predetermined horizontal viewing angle.
- 3. The liquid crystal display of claim 2, wherein said first, second, and third indices of refraction are termed nx, ny, and nz, wherein nx and ny define a plane and nz is oriented in a direction perpendicular to said plane.
- 4. The display of claim 3, wherein said plane is parallel to planes defined by each of said first and second negative retarders.
Parent Case Info
This is a continuation of application Ser. No. 09/048,322, filed Mar. 26, 1998; which is a cont. of Ser. No. 08/747,671, filed Nov. 12, 1996 (U.S. Pat. No. 5,737,048); which is a cont. of Ser. No. 08/255,971, filed Jun. 8, 1994 (U.S. Pat. No. 5,576,861); which is a CIP of Ser. No. 08/235,691, filed Apr. 29, 1994 U.S. Pat. No. 5,594,568); and a CIP of Ser. No. 08/167,652, filed Dec. 15, 1993 (U.S. Pat. No. 5,570,214), all of which are incorporated herein by reference.
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Continuations (3)
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Number |
Date |
Country |
Parent |
09/048322 |
Mar 1998 |
US |
Child |
09/334267 |
|
US |
Parent |
08/747671 |
Nov 1996 |
US |
Child |
09/048322 |
|
US |
Parent |
08/255971 |
Jun 1994 |
US |
Child |
08/747671 |
|
US |
Continuation in Parts (2)
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Number |
Date |
Country |
Parent |
08/235691 |
Apr 1994 |
US |
Child |
08/255971 |
|
US |
Parent |
08/167652 |
Dec 1993 |
US |
Child |
08/235691 |
|
US |