Electrically switchable computer-generated hologram recorded in polymer-dispersed liquid crystals

A computer-generated hologram (CGH) designed using the iterative Fourier transform algorithm was recorded in a cell filled with a polymer-dispersed liquid crystal material under a collimated He-Ne laser beam operating at 543 nm. Due to the photopolymerization induced phase separation, an index modulation was formed between the polymer-rich and liquid-crystal-rich regions. The results showed a good reconstructed image. With a suitable voltage applied, the reconstructed image can be erased due to the index change between the polymer and liquid crystal. Such electrically switchable CGH is potentially useful in information storage and adaptive optical elements. (C) 2007 American Institute of Physics.