Phase retarder and process for producing the same
Abstract
Abstract A phase retarder and a process for producing the same are disclosed. The phase retarder is obtained by shrinking a uniaxially stretched thermoplastic high polymer film in the direction perpendicular to the stretching direction at a lengthwise shrink of at least 2%. The phase retarder has a ratio of a retardation value (R 30 ) measured on the phase retarder being inclined at a angle of 30° with respect to the orientation axis as an axis of rotation to a retardation value (R 0 ) measured on the phase retarder being held horizontally, each measured with a polarizing microscope, (R 30 /R 0 ) of not more than 1.10, and preferably not more than 1.07. A liquid crystal display fitted with the phase retarder exhibits broad viewing angle characteristics while achieving a satisfactory B/W display level.
Inventors
- 👤 Toyokazu Okada
- 👤 Kazuaki Sakakura
- 👤 Koji Higashi
- 👤 Akiko Shimizu
Bibliographic Details
Claims Analysis
Total Claims: 4References Cited (Backward Citations)
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