Effects of Pulsed Electric Fields on a Nematic Device with a Ferroelectric Ceramic Substrate

Abstract

We report details of the interaction between a thin film of ferroelectric ceramic (lead zirconate-lead titanate) and an overlying layer of nematic liquid crystal. Pulsed electric fields of 1 ms duration and of varying amplitudes and polarity have been used to achieve different degrees of poling within devices in which one substrate includes the ferroelectric ceramic layer. The degree of orientation of the nematic liquid crystal is found to depend on both the amplitude and polarity of the poling voltage employed. The magnitude of the poling voltage necessary to induce reorientation in the liquid crystal compares reasonably with the calculated value. The reorientation of the nematic liquid crystal due to the interaction with poled grains of PZT is stable for at least several months.

Key Words:

• local Freederickz transition
• surface interaction
• nematic