Molecular orientational states and optical properties

The molecular orientational states of the SSFLCs have been analyzed by polarizing microspectroscopy and optical simulation. The X-ray studies indicated that the chevron layer structure is determined by the bulk properties of the FLC, but the molecular orientation in the smectic layer is strongly influenced by the surface properties. The effect of surface pretilt angle on the molecular orientation and the optical properties of SSFLCs have been studied by the optical simulation based on the molecular orientational models. 

Four states, CIU (Cl-uniform), CIT (Cl-twisted), C2U (C2-uniform), and C2T (C2-twisted), were found in SSFLC cells by investigating many samples aligned by various alignment films involving parallel rubbing [18]. These four states are expressed by a combination of the above two classifications. 

FLC material Apparent tilt angle/ Layer tilt angle/ Tilt angle/  

Aligning film Baking temperature /°C Pretilt angle/  

The CIU and C2U states are interesting from the practical point of view because they give the possibility of achieving a high contrast. 

O 2005 K( iki Takatoh, Masaki Hasegawa, Mitsuhiro Koden, Nobi uld Itoh, Ray Has awa and Masanoii Sakamoto 

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