偶氮基团(—N=N—)在适当波长光的照射下, 会发生可逆的顺反异构反应, 这一反应中偶氮分子构型上的变化会影响到蓝相液晶中脆弱的晶格结构, 并造成晶格参数的变化, 进而影响到选择性反射波长的变化, 甚至有时会造成蓝相相态的消失。文章合成并将几种偶氮化合物掺入手性向列相液晶中, 再变温至BPI, 对比了这几种偶氮化合物对蓝相液晶选择性反射波长的影响, 从而得出更有实际使用价值的偶氮分子, 在此基础上还从分子结构角度分析了产生差异的原因, 为进一步的改进工作提供了方向。

The azo (—N=N—) group can have reversible trans-cis isomerization reaction under the appropriate wavelength light irradiation. The change of the azo molecular configuration affects fragile lattice structure of the blue phase liquid crystal and leads to the change of the lattice parameters, thus the selective reflection wavelength is also changed. Sometimes the change of azo molecular configuration can make the blue phase disappeared. In this paper several azo compounds were synthesized and doped in chiral nematic phase liquid crystal, then the temperature was changed to get blue phase I. The influence of selective reflection wavelength was studied and the azo compounds suitable for application were found. The reason of the difference was also discussed and the suggestion for further improvement was given.