Talbot Effect by Photorefractive 3D Phase Gratings

G. FORTE; A. LENCINA; M. TEBALDI; N. BOLOGNINI

Lima

Congreso; VII REUNIÓN IBEROAMERICANA DE ÓPTICA - X ENCUENTRO LATINOAMERICANO DE ÓPTICA, LÁSERES Y SUS APLICACIONES; 2010

The self-images intensity distribution in the near field of a volume phase grating coherently illuminated is analyzed. In order to generate this grating an image of incoherently illuminated amplitude plane grating is projected in a photorefractive crystal. This 3D image is mapped into an index refractive perturbation via the photorefractive effect thereby generating a volume phase grating. Simulated self-image patterns are calculated using a path-integral approach to take into account the inhomogeneous and non linear propagation through the photorefractive medium. The results show that the self-images location coincides with that of the self-images generated by plane phase grating of the same period. Besides, the self-images visibility depends on the f/# of the grating recording optical system, the external electric field applied on the crystal and the crystal thickness, as proved by previous experimental results. A good agreement between theoretical and experimental results is observed.approach to take into account the inhomogeneous and non linear propagation through the photorefractive medium. The results show that the self-images location coincides with that of the self-images generated by plane phase grating of the same period. Besides, the self-images visibility depends on the f/# of the grating recording optical system, the external electric field applied on the crystal and the crystal thickness, as proved by previous experimental results. A good agreement between theoretical and experimental results is observed.