Sheremet Nina, Kurioz Yuriy, Slyusarenko Kostyantyn, Trunov Michael, Reznikov Yuriy
Institute of Physics, Kyiv, Ukraine.
Appl Opt. 2013 Aug 1;52(22):E40-6. doi: 10.1364/AO.52.000E40.
Polarization gratings have been recorded in a combined liquid crystal (LC) cell made of a substrate covered with a photosensitive chalcogenide orientation layer and a reference substrate covered with a rubbed polyimide film. The gratings are formed due to the spatially modulated light-induced easy orientation axis on the chalcogenide surface recorded by two beams with opposite circular polarizations. The gratings are permanent, but they can be erased by one of the recording beams and re-recorded. The diffraction intensity of the circularly polarized light is achromatic and does not depend on the birefringence of the LC. The diffraction efficiency of the grating is of the order of a few percents. Application of an ac field causes a strong increase of the diffraction efficiency up to 45%.
偏振光栅已记录在由覆盖有光敏硫属化物取向层的基板和覆盖有摩擦聚酰亚胺膜的参考基板制成的组合液晶(LC)盒中。这些光栅是由于在硫属化物表面上由具有相反圆偏振的两束光记录的空间调制光致易取向轴而形成的。这些光栅是永久性的,但可以被其中一束记录光束擦除并重新记录。圆偏振光的衍射强度是消色差的,并且不依赖于液晶的双折射。光栅的衍射效率约为百分之几。施加交流电场会使衍射效率大幅提高,高达45%。