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Active matrix liquid crystal displays (AMLCDs) have narrow and non-uniform viewing angle characteristics. Numerical simulations using 2 x 2 matrix method have been done to improve the narrow viewing angle characteristics of conventional twisted-nematic (TN) LCDs. Several structures including multi-domain TN-LCDs and retardation film compensated TN-LCDs have been studied. More symmetric and wider viewing angle characteristics can be obtained using a multi-domain structure, but the contrast ratio is reduced. Using hybrid negative retardation films, the contrast ratio has been improved dramatically. However, reverse image and extensively dark image regions still exist. To overcome these problems, a novel TN-LCD structure with wide viewing angle characteristics has been designed. This new structure is featured by the two-domain structure of both the retardation film and TN-LC cell. The simulated results indicate that this new structure can provide excellent viewing angle characteristics. The process to achieve this novel structure is also proposed. The chemical and physical changes in both the rubbed and un-rubbed polyimide films induced by both polarized and un-polarized UV-light illumination have been studied through both spectroscopic and surface analysis. UV-light illumination of polyimide films generates more polar groups by bond-breaking and oxidation reactions, which cause the increase of both the surface tension and polarity. Consequently, the LC pretilt angles of the rubbed polyimide films decrease with the illumination time. Both LC alignment and pretilt angle were generated on un-rubbed polyimide films by the double exposure method during the photoalignment process. Anisotropic polyimide films are formed after polarized UV-light illumination. Uniform LC alignment on polarized UV-light illuminated, un-rubbed polyimide films results from the anisotropic interactions between the LC molecules and the resulting anisotropic polyimide film. The LC pretilt angle generated by oblique P-polarized UV-light illumination during the photoalignment process could be associated with the breakage of the two-fold symmetry of the original random LC pretilt along the alignment direction. This mechanism is supported by the effects of polarized UV-light illumination on the LC pretilt angles of rubbed polyimide films.