Spatially resolved refractive index profiles of electrically switchable computer-generated holographic gratings.
We describe a spatially resolved interferometric technique combined with a phase reconstruction method that provides a quantitative two-dimensional profile of the refractive index and spatial distribution of the optical contrast between the on-off states of electrically switchable diffraction gratings as a function of the external electric field. The studied structures are holographic gratings optically written into polymer/liquid crystal composites through single-beam spatial light modulation by means of computer-generated holograms. The electro-optical response of the gratings is also discussed. The diffraction efficiency results to be dependent on the incident light polarization suggesting the possibility to develop polarization dependent switching devices.
Zito
Gianluigi
G
Istituto di Cibernetica E Caianiello"del Consiglio Nazionale delle Ricerche, Via Campi Flegrei 34, 80078 Pozzuoli, Na, Italy.
Finizio
Andrea
A
De Nicola
Sergio
S