Patent ID: 9011992
Filing Date: 2015-04-21
Classification: C09K,G02B,G02F

Abstract:
1. A uniaxially stretched polymer film having a refractive index profile of n x <n y ≦n z , which satisfies the relation of n y −n x >0.001, wherein n x is the in-plane refractive index parallel to the film stretching direction, n y is the in-plane refractive index perpendicular to n x , and n z is the thickness refractive index, where the stretched polymer film is prepared by stretching an unstretched polymer film made from a polymer capable of being solution cast into a positive C plate with a refractive index profile of n x =n y <n z and the relation of n z −(n x +n y )/2>0.002, wherein the unstretched polymer film is prepared by solution casting a polymer solution comprising a polymer having a moiety of wherein R