Physical Review E
A simple theoretical model of liquid crystal (LC) alignment by exposure to linearly polarized ultraviolet (UV) light is proposed. The model predicts a universal relationship describing the change of the LC anchoring direction with exposure times, and the changes of polarization direction for the case of a double linearly polarized UV exposure process. This relationship is quantitatively confirmed by our experimental results on polyimide systems. The model also suggests that the LC anchoring strength can be controlled by UV exposure dosage. Pretransitional birefringent measurements show that the order parameter of a linearly polarized UV exposed polyimide surface is much lower than that of buffed polyimide films.
Chen, J.; Johnson, D. L.; Bos, Philip J.; Wang, Xinghua; and West, John L. (1996). Model of Liquid Crystal Alignment by Exposure to Linearly Polarized Ultraviolet Light. Physical Review E 54(2), 1599-1603. Retrieved from http://digitalcommons.kent.edu/cpippubs/33