臺灣博碩士論文加值系統

液晶聚合物混合材料是近年來最受重視的光電材料，而利用NdYag 雷射來
觀測材料中的二諧光波的產生（SHG），能對元件的結構變化作定性的分
析。而液晶聚合物薄膜所產生的SHG主要的貢獻是來自液晶聚合物介面和
膽固醇液晶相互間的介面的介電常數差。此外紫外光的硬化強度、單體濃
度入射光偏振、驅動電壓、驅動電壓頻率、液晶材料的改變等均會改變薄
膜的結構，而由SHG強度的變化我們可觀測得這些結構變化.由於SHG和光
電效應以及聚合物的枝條結構有著相互對應的關係，所以SHG此種非線性
的光學效應，是除了光電效應外另一種被用來分析液晶聚合物混合薄膜的
定性、非破壞性的分析方法。鐵電性液晶最大的特點在於當其受外加電場
作用時反應時間(~10μs)比其它類現今已知的液晶快，而加入鐵電性液晶
後PSCT薄膜的性質將會改變，由研究PSCT薄膜性質的改變我們可以改進傳
統的display。

Film of liquid crystal (LC)-polymer dispersion material
were fabricated.Using a mode -locking Nd:Yag laser,we observer
second harmonic generation(SHG) in thesemixtures which is due to
the dielectric difference across the interfaces between the the
LC/polymer network and those between adjacent cholesteric
domains having a different helical axis.The results showed that
ferroelectric liquid crystal concentrations affected SHG
intensity significantly. Good correlations among SHG
mesurement and electro-optical characteristics.This means that
SHG mesurements could provide us with another qualitative,
nondestructive method to analyze PSCT films. Characteristics
of ferroelectric liquid crystal were its response timefaster
than other kinds of liquid crystal .Studies of SmC* doped in
PSCT will improve defects of traditional display.