Patent · US Active

Optical film, image display device, and liquid-crystal display device

US7456919B2 · kind B2 · utility

0Cited by
2References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 22, 2006
Grant dateNov 25, 2008
Priority date
Expiry dateJun 1, 2027

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F2413/07
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An optical film includes: a polarizer having an absorption axis; and at least three retardation films, each having a slow axis, wherein the absorption axis of the polarizer intersects the slow axis of each of the at least three retardation films at right angles and is parallel to the slow axis of each of the at least three retardation films, the slow axis of each of the at least three retardation films are parallel to each other, a total amount of Nz value of each of the at least three retardation films, the Nz value being defined by formula (I), is half as many as the number of the at least three retardation films, and an in-plane retardation Re1 of each of the at least three retardation films, the in-plane retardation Re1 being defined by formula (II), ranges from 200 to 350 nm:Nz=(nx1−nz1)/(nx1−ny1)   (I)Re1=(nx1−ny1)×d1 .   (II)

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.