Formation of periodic phase structures in a photopolymerizable layer by nonstationary light beams

Photopolymerization of a composite containing a nonpolymerizable component under the action of nonstationary optical radiation is studied. It is shown that the diffusion displacement of the nonpolymerizable component at the illuminated region boundary is caused by the appearance of the monomer concentration gradient, which, in turn, is induced by nonuniform photoinitiation. The action of radiation with a nonstationary intensity distribution makes it possible to form a periodic refractive index structure in the volume of the photopolymerizable material. The possibility of optical formation of polymer phase gratings by moving the shadow boundary stepwise along the polymerizable layer is studied numerically and experimentally.