Holding Characteristic of Dark State in Antiferroelectric Liquid Crystal

The holding characteristic of the dark state of antiferroelectric liquid crystal (AFLC) displays have a crucial effect on the contrast ratio. We have studied the dependence of the transmittance in the dark state on the waveform of the applied voltage in multiplex driving for several materials. The samples used were 4-(1-methylheptyloxycarbonyl)phenyl-4'-octyloxybiphenyl-4-carboxylate (MHPOBC) and its homologues. It was found that the holding characteristics of the dark state are affected by the applied waveforms and the chemical structures such as the type of chiral radical and the length of the alkyl chain.