LIQUID CRYSTALS: PHYSICS, TECHNOLOGY AND APPLICATIONS
|
1998年
/
3318卷
关键词:
liquid crystals;
diffraction optical elements;
D O I:
10.1117/12.300028
中图分类号:
TM [电工技术];
TN [电子技术、通信技术];
学科分类号:
0808 ;
0809 ;
摘要:
In this paper consideration is being given to the principle underlying the operation of switchable diffraction elements based on the relief grating of isotropic material and nematic liquid crystals contacting it. Electrical control of the phase grating diffraction efficiency has been experimentally realised. The problems of LC orientation on the relief substrate have been considered. Consideration has also been given to the optical diffraction lens with switchable focal lengths and to two - layer systems operating with radiation of any polarisation. It has been demonstrated that LC having large value of optical anisotropy (similar to 0.2) are most suitable for this application. The requirements to liquid crystals to be used in optical elements are covered.