Fig. 1: Sketch of light-induced deformation mechanisms.
From: Polarization-driven reversible actuation in a photo-responsive polymer composite

a azo-SEBS film deposited on a PDMS layer, (b) self-standing azo-SEBS membrane; (c) illustrative deformation of azopolymer microdomains upon linearly polarized laser irradiation, leading to overall stretching of the azo-SEBS layer on PDMS along the polarization direction; (d) inhomogeneous stretching of the free-standing azo-SEBS membrane and corresponding bending caused by the gradient of absorbed light through the membrane. Both SEBS and PDMS are translucent/transparent materials in the real world.