Patent ID: 7088511
Filing Date: 2006-08-08
Classification: G02B

Abstract:
1. A method of producing a light polarizing film comprising: providing an oriented sheet of polyvinyl alcohol having a first surface and a second surface and having a polarization direction; simultaneously biaxially stretching a polypropylene film, whereby the polypropylene film is simultaneously biaxially oriented; disposing an optical retarder comprising the simultaneously biaxially oriented polypropylene film adjacent to the first surface of the linear polarizer; orienting an axis of the optical retarder at an angle to the polarization direction of the linear polarizer; disposing an adhesive layer between the first surface of the linear polarizer and the optical retarder, the adhesive layer having a minimum adhesion strength of about 25 grams per inch; disposing a second optical retarder comprising a simultaneously biaxially oriented polypropylene film adjacent to the second surface of the linear polarizer; and orienting an axis of the second optical retarder at a 45 degree angle to the polarization direction of the linear polarizer.