The Change in Refractive Index and the Formation of Birefringence during Photoisomerization of Photochromic Dyes

The optical switching devices in optical computing systems usually use electro-, acousto- optic and nonlinear optical effects. Photochemical reactions can be potentially used as one of the principles for photo-optical switching devices, because they change the electric structure of the system.1 In this study, the change in refractive indices of PMMA films containing DAAB (p- dimethylaminoazobenzene) during photoisomerization and the birefringence during polarized-light induced photoisomerization were measured, and the possibility as a photo-optical controlling material was examined.