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A polymer with azobenzene sidechains acts as a command layer for reversible switching of liquid crystal (LC) optical waveguides. Exposure of the LC to UV and blue light causes optical switching. Regulation of the intensity and time of exposure enables orientation of the switching state. The cis-trans chromophore concentration ratio on the command surface influences the degree of orientation.

Two photochromic command surfaces containing an ultrathin polymer film with azobenzene side chains function as controllers of the orientation, configuration and optical properties of a liquid crystal optical waveguide. Light exposure causes a reversible trans to cis photoisomerization of the azobenzene side chains, resulting in modifications in the orientation and refractive indices. Microscopic studies indicate a storing time that ranges between several hours for the optical waveguide.