HEAT SETTING OPTICAL FILMS

摘要

PROBLEM TO BE SOLVED: To provide a method of producing a heat setting optical film that enables an in-plane block state and an in-plane pass state for light normally incident to a plane of a film that functions as a linear polarizer.SOLUTION: A method of producing a heat setting optical film 32 having a linear polarizer function includes providing an apparatus with a film 32 comprising a polymeric material capable of developing birefringence; stretching the film 32 in a stretching region 66 to substantially uniaxially orient the film; and then heat setting the oriented film 84. The polymeric material capable of developing birefringence is selected from among polyethylene naphthalate, polyethylene terephthalate, polypropylene and syndiotactic polystyrene.