| 초록 |
Ferroelectric Liquid Crystal Display(FLCD) has been paid many attentions as a potential display due to its characteristics such as a memory effect and fast response1. Fast response of FLC molecules originates from the coupling of spontaneous polarization with applied electric field. Interactions between FLC and allignment layer in surface-stabilized FLCD make memory effect possible. These features are useful in realizing a large-scale flat display. The value of response time decreased at the high frequency. This results suggest the presence of a depolarization field at the lower frequency, due to the accumulation of excess ions on the interfaces between the FLC medium and the alignment layers7. This residual ionic field lowers the effective field and reduces the switching speed. The switchings of FLC on the LB PI film become faster as surface pressure increase because of the increase of overall Ps. The switching speed is proportional to the inverse of Ps as tr = (/ P(E, where t is switching time, ( cone mode viscosity, P Ps, E electric field. The decrease of slope represents the effect of ionic field on the response time. The response time decreases proportionally with the electric field and Ps. Remarkable phenomena, however, occurred at the lower voltage. In this region, full switching was not obtained. Some amounts of FLCs are not switched which are more stable that need larger field. It is proposed that the observed response time is that of switched FLC which is more easily switchable to the applied field.
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