Linear optical anisotropy in aromatic polyimide films and its applicaitons in negative birefringent compensators of liquid crystal displays

摘要

Samples of soluble aromati polymidies of varying chemical strucure and modlecular weight wre synthesized in refluxing m-cresol at elevated temepratures thoruh a one-step opolymerizaiton route.modificaitons of the dianhydride and diamine monomers wre designed to repare aromatic polymides having nw architecures based n the requriements of liquid crytal display (LCD) applciatiosn.hte solution cast films exhibit linear opitcla anisotropy (LOA),which is called uniaxial negative birefringence (UNB) and is characteized by the presence of a larger refractive index along th in-plane direction than in the out of-plane direction.