IP Library Granted Patent US 8,400,591
Granted Patent B2
US 8,400,591 · App. 12/989,746 · Granted Mar 19, 2013

Video image evaluation equipment

Inventors: Hiroyuki Yoshimi (Ibaraki, JP); Kentarou Takeda (Ibaraki, JP); Hiroaki Sawada (Ibaraki, JP); Masaki Hayashi (Ibaraki, JP)
Assignee: Nitto Denko Corporation
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Quick Facts
Patent No.
US 8,400,591
App. No.
12/989,746
Granted
Mar 19, 2013
Kind
B2
Abstract

A video image evaluation equipment of the present invention is capable of converting circularly-polarized light emitted from a circularly polarizing light source into linearly-polarized light so as to transmit an absorption-type linear polarizer by a wavelength plate to be incident on a liquid crystal panel. This makes it possible to enter and reflect light emitted from the circularly polarizing light source on the liquid crystal panel without loss, which leads to display brighter video images than conventional ones.

Claims (10)

1. A video image evaluation equipment comprising:

a liquid crystal display; and

a circularly polarizing light source arranged outside the liquid crystal display,

wherein the liquid display comprises in order from the circularly polarizing light source-side:

a wavelength plate having functions to convert circularly-polarized light into linearly-polarized light and vice versa; an absorption-type linear polarizer; and a liquid crystal panel,

wherein the liquid crystal panel comprises: a liquid crystal layer used as a display medium; and a reflective layer arranged on the opposite side to a viewer-side of the liquid crystal layer,

wherein the wavelength plate is so arranged that the linearly-polarized light transmits the absorption-type linear polarizer.

2. The video image evaluation equipment according to claim 1 , wherein the wavelength plate is a quarter wavelength plate.

3. The video image evaluation equipment according to claim 1 or claim 2 , wherein an optical film having a helical structure is arranged on a lighting apparatus for emitting natural light or a window for passing natural light in the circularly polarizing light source.

4. The video image evaluation equipment according to claim 3 , wherein the optical film having a helical structure is an optical film in which a liquid-crystalline compound exhibiting a cholesteric phase is solidified.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 28, 2010
From: YOSHIMI, HIROYUKI; TAKEDA, KENTAROU; SAWADA, HIROAKI; HAYASHI, MASAKI
To: NITTO DENKO CORPORATION
Reel/Frame 025209/0993 →
Priority Claims (1)
JP 2008-127821 · May 15, 2008 · national
Continuity (1)
Related Publication 20110032437A1 · Feb 10, 2011