Pretilt angle effects on critical voltage and dynamic response of pi cell

The critical voltage with an arbitrary pretilt angle is given analytically which is consistent with the numerical results [ Acosta , Liq. Cryst. 27 , 977 ( 2000 ) ]. The author's results show that the critical voltage is dependent on the parameters of liquid crystal and pretilt angle but is independent of the cell gap. By numerical simulation the authors find that the on time of pi cell decreases with the increasing pretilt at the same voltage, and the off time of the cell driven by the undershoot method is much faster than that of the normal driven method for the cell with nonzero critical voltage.