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:
Sep. 23, 2008
Filed:
Jul. 29, 2003
Nao Murakami, Ibaraki, JP;
Hiroyuki Yoshimi, Ibaraki, JP;
Yuuichi Nishikouji, Ibaraki, JP;
Masaki Hayashi, Ibaraki, JP;
Nao Murakami, Ibaraki, JP;
Hiroyuki Yoshimi, Ibaraki, JP;
Yuuichi Nishikouji, Ibaraki, JP;
Masaki Hayashi, Ibaraki, JP;
Nitto Denko Corporation, Ibaraki-shi, JP;
Abstract
The present invention relates to an optical film that is excellent in optical properties and can be produced at low cost. In the optical film formed by laminating a transparent polymer film layer and a birefringent layer of a non-liquid crystalline polymer, the birefringent layer satisfies a condition represented by nx≧ny>nz and the in-plane retardation of the transparent polymer film layer is 50 nm or less. In the above formula, nx, ny and nz are the refraction indices in the X-, Y- and Z-axes directions of the birefringent layer, respectively. The X-axis direction is the axial direction in which the refraction index shows a maximum value in the in-plane direction of the birefringent layer, the Y-axis direction is the axial direction perpendicular to the X-axis direction in the plane, and the Z-axis direction is the thickness direction perpendicular to the X- and Y-axes directions.