Abstract
The π cell is one of the most promising liquid-crystal-display modes since it has the advantages of fast optical response and wide viewing angle characteristics regarding gray scale inversion. To realize a wide viewing angle, we have prposed the use of a discotic negative birefringence film with a hybrid alignment structure, which compensates the positive birefringence of the liquid crystals in the dark-state π cell. Although the discotic negative birefringence film completely compensates the positive birefringence of the liquid crystals, the compensated π cell still suffers low contrast ratio at oblique incidence. This is due to the light leakage of polarizers from oblique angles. We realized further wide viewing angle characteristics for the compensated π cell by combining an a-plate, which suppresses the light leakage of polarizers at oblique incidence.
