The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 26, 2008
Filed:
Jul. 24, 2006
Satoru Kawahara, Ibaraki, JP;
Masaki Hayashi, Ibaraki, JP;
Shuuji Yano, Ibaraki, JP;
Kenji Yoda, Ibaraki, JP;
Kentarou Kobayashi, Ibaraki, JP;
Satoru Kawahara, Ibaraki, JP;
Masaki Hayashi, Ibaraki, JP;
Shuuji Yano, Ibaraki, JP;
Kenji Yoda, Ibaraki, JP;
Kentarou Kobayashi, Ibaraki, JP;
Nitto Denko Corporation, Ibaraki-shi, Osaka, JP;
Abstract
A retardation film of the present invention comprises a stretched film of a polymer film containing a norbornene-based resin, wherein the stretched film satisfies the following equation (1) and the equation (2); 100 nm≦(nx−ny)·d≦350 nm . . . (1), 0.1≦(nx−nz)/(nx−ny)≦0.9 . . . (2), where the refractive indices in the slow axis direction, the fast axis direction and the thickness direction of the film are nx, ny and nz, respectively, d(nm) is thickness of the film, and the slow axis direction is a direction that the refractive index in film plane is maximum. The retardation film is hard to cause a shift or an unevenness of a retardation value due to a stress.