Hideki Yoshinaga

Dot Inversion Spontaneous Polarization Structure in the Half-V-shaped Switching Ferroelectric Liquid Crystal Mode

The half-V shaped switching ferroelectric liquid crystal mode (half-V FLC mode) can easily yield excellent moving pictures based on the nonholding display by simple AC driving. However, the AC driving in the entire area of the liquid crystal display (LCD) panel (i.e. the field-inversion drive method) raises a concern of the cross talk problem in large-size LCD panels. In this paper, we propose a novel alignment method that is controlled to yield alternating layer directions between neighboring pixels. Such layer structures correspond to the structure of dot inversion spontaneous polarization, and a nonholding display can be realized by the dot-inversion drive method. By this method, we can simultaneously obtain a cross-talk-free display, excellent moving pictures and wider viewing angle. The contrast ratio is expected to be improved by further liquid crystal development and/or the multi-domain process technology.

Analysis of the Hysteresis Phenomenon in the Intrinsic Half-V-Shaped Switching Ferroelectric Liquid Crystal Mode

The intrinsic half-V-shaped switching ferroelectric liquid crystal mode (iHV-FLC mode) is known to be able to easily yield excellent moving pictures without blurring, based on the nonholding display by simple AC driving in the ideal condition. However, we have sometimes observed the blurred moving pictures even in the iHV-FLC mode with very short response time. We have conducted the detailed measurement of the electrooptical response. The protracted hysteresis phenomenon could be observed in some cells. This phenomenon had a strong relationship with the internal ionic impurity density. The 1st frame hysteresis phenomenon could be observed even in the purest cells. It is considered to be caused by the c-director position at zero field and its driving scheme.