All-optical fabrication of blazed grating on Pcyclic-azoMMA film

Blazed grating is a key diffractive optical element in spectrometer. Different from the traditional holographic ion beam etching method, blazed grating has been fabricated on a novel polymer with cyclic-azobenzene pendants (Pcyclic-azoMMA) by all optical fabrication with two steps in this paper. Firstly, use two interfering Kr+ laser beams with the most efficient RCP+LCP polarization to inscribe symmetric surface relief gratings on polymer film. After that, make a single laser beam with polarization perpendicular to the grating grooves irradiate slantly to induce blazed asymmetric structure. The distribution of the near field of the grating while single linearly polarized beam irradiate slantly at different angles was simulated. The calculation demonstrates that -1st order diffraction efficiency of blazed gratings is similar to that of triangle blazed grating.