Diffraction efficiency enhancement caused by employing liquid crystal phthalonitrile derivative in nematic liquid crystals

The change of refractive index, originated by photoinduced molecular reorientation, brings about a significant diffraction capability in E7 coded nematic liquid crystal system doped by 2,3-dicyano-1,4-di[3,4,5-tri(dodecyloxy)phenylcarbonyloxy]benzene (DCDPB) which is called as liquid crystal phthalonitrile derivative. Results of a grating diffraction experiment are reported for the constructed sample. The accessible diffraction efficiency, η, is roughly of the order of 10% under the optimum conditions and analysed results propose this novel system to be appropriate and promising for the excitation wavelength of a 632.8 nm He–Ne laser.