OPTOTHERMAL REORIENTATION OF NEMATICS WITH 2-FOLD DEGENERATE ALIGNMENT

The preferred direction of alignment of the liquid crystal molecules i n nematics with two-fold degenerate alignment can be affected substant ially by changing the temperature or by applying an electric field. As a result, an almost in-plane switching of the molecules occurs. Here, we report an opto-thermal reorientation effect in a nematic with two- fold degenerate alignment due to a local heating of the liquid crystal by a high power laser beam. The mechanism of this phenomenon is discu ssed. The opto-thermal reorientation of the molecules makes it possibl e to visualize the temperature distribution in the illuminated cell an d some applications can be foreseen.