Polarizers ferroelectric LCDs

Surface stabilized mode ferroelectric LCDs [31-35] show bistability, i. e. both the and the -6 position are equally stable. A pulse of one polarity is used to switch from 6 to -6, while a pulse of opposite polarity is used to switch from -0 to 6. The molecules can remain in either of these states (0 or -6) for a long time without any applied voltage. In the case of GH ferroelectric LCDs, the ferroelectric mixture contains an appropriate... 

The orientation of liquid crystals can be influenced by an electric field. This property makes LCPs attractive for LCDs. Some liquid crystals undergo a spontaneous electric polarization even in the absence of an external electric field. This phenomenon is referred to as a ferroelectricity. 

Ferroelectric liquid crystals were discovered about 35 years ago [118]. They gained interest, because of their chiral structure which provided optical activity, their fast response for display applications, and their bistable and polar structure. The fact that some of those compoimds that are now used in LCDs are based on chiral pharmaceuticals and pesticides added to their fascination, and research flourished in the 1990s when around 40 domestic companies synthesized an amazing number of more than 1,000 compounds ... 

A number of moleoiles that exhibit a ferroelectric (F) phase or an anti-ferroelectric (AF) phase (Figure 2) such as methyl-substituted MHPOBC (18) and the trifluoromethyl analogue, TFMHPOBC (19) with greater spontaneous polarization (Ps) (Figure 3), have been prepared and their physical properties have been investigated because of potential application in electro-optic devices for liquid-CTystalline displays (LCDs) (20). The AFLC molecules show quite useful characteristics such as a tri-stable switching, sharp DC threshold, and double-loop-hysteresis. 

---