摘要(英) |
Surface-stabilized ferroelectric liquid crystals (SSFLCs) possess their unique characteristics of fast response and bistability. Many scientists have been paying much attention to this research topic in recent decade. Although SSFLCs have the advantages mentioned above, some shortcomings, such as Chevron defect, horizontal defect, and the limitation of small cell gap and uniformity, should be considered. Generally speaking, to obtain the property of bistability, the cell gap of the SSFLC cell is limited to be smaller than 2 m. As a result, the cell fabrication processes are extremely difficult so that the researches in this field gradually decrease.
The rotation range in the plane of the LC cell of SSFLC molecules is dependent on the cone angles of the FLCs. According to our experimental results, the cone angle of the FLCs can be modulated by doping azobenzene materials into smectic C / smectic C*, and by illuminating with UV light. Moreover, the stability of azobenzene-doped SSFLCs can be enhanced by illuminating with UV light to get cis-azobenzenes, having relatively high electric dipole moment. To establish the mechanism of the generation of the SSFFLC stability, the electro-optical properties of SSFLCs, prepared by the mixtures of various azobenzenes and smectic C / smectic C*, have been studied before and after been treated with UV illumination. Accordingly, we believe that such a novel approach can improve the developments of the SSFLC in LC technology.
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參考文獻 |
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