胆甾相液晶光谱带宽与手性掺加剂的关系

The Relation Between the Spectrum Bandwidth of the Cholesteric LC and the Chiral Dopant

文章从胆甾相液晶的反射波长和螺距的关系出发,按照λ0=np,n=(2no+ne)/3,可以得出布拉格反射波长,其中λ0是一个定值,p=1/(c×HTP)。在向列相C5中添加不同HTP值的手征性掺加剂,通过调节手征性掺加剂的添加浓度,能够得到相同螺距的胆甾相液晶。利用DMS-501光谱测试仪测试制备的胆甾相液晶,可明显得出:相同的反射波长,其光谱带宽却不同,结果为:添加HTP值越大的手征性掺杂剂,胆甾相液晶光谱带宽越宽,开口越大;反之,添加HTP值越小的手征性掺杂剂,胆甾相液晶光谱带宽越窄,开口越小。

We can get the Bragg reflect wavelength according to λ0=np,n=（2,10＋ne）/3 from the relation between the reflect wavelength and pitch of cholesteric LC, and the ,λ0 is a fixed value, p=1/（c x HTP）. The chiral dopant with different chiral power is added to the same C5 nematic phase LC and we can get the cholesteric LC with the same pitch through adjusting the added concentration of the chiral dopant. The conclusion is that the spectrum bandwidth is different though the reflect wavelength is the same from the DMS-501 testing data. The result is that the spectrum bandwidth is wide when the chiral dopant with high HTP value was added into the nematic LC, contrarily the spectrum bandwidth is narrow when the chiral dopant with low HTP value was added into the nematic LC.