Self image phenomenon through a grating stored in a 3D medium

GUSTAVO FORTE; ALBERTO LENCINA; MYRIAN TEBALDI; NESTOR BOLOGNINI

Sidney (Australia)

Congreso; 20th Congress of the International Commission for Optic; 2008

International Comission of Optics

The storage and diffraction properties of a 1-D coarse grating imaged onto a volume medium are analyzed. The conventional self-image effect does not consider the diffraction process from a 3 D structure. In our case, the self images are studied in terms of the medium depth, optical aperture system (f #) and grating spatial frequencies. The theoretical approach proposes a model that describes the image formation in the volume medium and resembles the behavior of the photorefractive volume crystal. Experimental results that confirm our approach are presented. These results are obtained by using a grating stored as modulation of birefringence in a photorefractive medium. The visibility behavior of the self-images by propagation is similar to the conventional Talbot experiment produced with a plane pure phase grating. However, we demonstrate by adequate controlling the mentioned parameters the fringe visibility could be improved in the self imaging planes.