Optical film and its manufacturing method
US7428029B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 29, 2003 |
| Grant date | Sep 23, 2008 |
| Priority date | — |
| Expiry date | Oct 25, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/133528
- WIPO fieldOptics
- WIPO sectorInstruments
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.