IP Library Granted Patent US 7,880,838
Granted Patent B2
US 7,880,838 · App. 11/356,127 · Granted Feb 1, 2011

Liquid crystal device, projection apparatus, and electronic apparatus

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Quick Facts
Patent No.
US 7,880,838
App. No.
11/356,127
Granted
Feb 1, 2011
Kind
B2
Abstract

A projection display includes a light source, a liquid crystal panel encapsulating a vertical alignment mode liquid crystal between a first substrate and a second substrate which are opposite to each other, the liquid crystal panel modulating light emitted from the light source, a longer axis of a molecule of the vertical alignment mode liquid crystal tilted from the normal direction of the first substrate, a projection lens projecting light modulated by the liquid crystal panel, a first polarization plate placed on an optical path from the light source to the liquid crystal panel, a second polarization plate placed on an optical path from the liquid crystal panel to the projection lens, an optical-compensation plate placed between the liquid crystal panel and the second polarization plate, and the optical-compensation plate including a plate-like base and a retardation plate formed on a surface of the plate-like base.

Claims (19)

1. A projection display comprising:

a light source emitting light;

a liquid crystal panel encapsulating a vertical alignment mode liquid crystal between a first substrate and a second substrate which are opposite to each other, the liquid crystal panel modulating light emitted from the light source, a longer axis of a molecule of the vertical alignment mode liquid crystal tilted from the normal direction of the first substrate;

a projection lens projecting light which is modulated by the liquid crystal panel;

a first polarization plate placed on an optical path from the light source to the liquid crystal panel;

a second polarization plate placed on an optical path from the liquid crystal panel to the projection lens; and

an optical-compensation plate placed between the liquid crystal panel and the second polarization plate, the optical-compensation plate including;

a plate-like base which is opposite to the second polarization plate, the plate-like base having a delay axis within a plane which is in parallel with a plate side of the plate-like base, the delay axis of the plate-like base is in parallel with a transparent axis of the second polarization plate; and

a retardation plate formed on a surface of the plate-like base, in which each of major refractive indexes intersecting each other within a plane that is in parallel with the retardation plate, is different from each other among the major refractive indexes, the retardation plate which is opposite to the liquid crystal panel, a direction of a fast or slow axis within a plane of the retardation plate is different from a direction of the tilted longer axis in which the molecule of the vertical alignment mode liquid crystal is normally projected to the surface of the first substrate, and a direction of the transparent axis of the second polarization plate or a direction of a transparent axis of the first polarization plate.

2. The projection display according to claim 1 , the plate-like base of the optical-compensation plate including a material of which thermal conductivity is higher than that of the retardation plate.

3. The projection display according to claim 1 , the liquid crystal including a molecule, the molecule having a longer axis and a shorter axis, the first substrate including an alignment film, the alignment film disposing the molecule, an angle θ between a direction of the longer axis and a normal direction of the first substrate satisfying the following relationship;

0°≦θ≦10°.

4. The projection display according to claim 3 , the alignment film including an inorganic material.

5. The projection display according to claim 1 , the liquid crystal including a molecule, the first substrate including an alignment film, the alignment film disposing the molecule, the molecule having a shadow on the surface of the first substrate when the molecule is normally projected to the surface, the shadow having a longer axis and a shorter axis, an angle θ between a direction of the longer axis and another direction in parallel with a plane of the retardation plate satisfying the following relationship;

40°≦θ≦50°.

6. The projection display according to claim 1 , one of the major refractive indexes of the retardation plate being nx, another of the major indexes of the retardation plate being ny, a thickness of the optical-compensation plate being d 0 , the nx, the ny, and the d 0 satisfying the following relationship;

20(nm)<( nx−ny )× d 0(nm)<180(nm).

7. The projection display according to claim 1 , one of the major refractive indexes of the retardation plate being nx, another of the major refractive indexes of the retardation plate being ny, a refractive index nz, of which direction is orthogonal to each direction of the major refractive indexes (nx, ny), a retardation of the liquid crystal being Δ nd, a thickness of the optical-compensation plate being d 0 (nm), the nx, the ny, the nz, the Δnd the d 0 (nm) satisfying the following relationship;

Δ nd× 0.3<[( nx+ny )/2· nz]<Δnd× 0.8.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 15, 2018
From: SEIKO EPSON CORPORATION
To: 138 EAST LCD ADVANCEMENTS LIMITED
Reel/Frame 046153/0397 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 17, 2006
From: OZAWA, KINYA
To: SEIKO EPSON CORPORATION
Reel/Frame 017599/0513 →