Light-Controlled Anchoring Energy in Nematic Liquid Crystals

In this paper we show the possibility of regulating the dose of the anchoring energy under the control of the incident light. Using a dye-doped nematic sample where it was previously demonstrated the effect of light-induced anchoring, we measured the threshold for the Fred-ericksz transition for different irradiation times using a low power laser beam. Our data compare favourably to the existing theory and show that the amount of induced anchoring energy increases linearly with the irradiation time.