title: In situ optical control and stabilization of the curing process of holographic gratings with a nematic film-polymer-slice sequence structure.
abstract: We report on the realization of what we believe to be a new holographic setup for the fabrication of polymer liquid-crystal polymer-slice diffraction gratings, which utilizes an optical-feedback-driven nanopositioning technique. We have increased the stability of the interference pattern by means of a simple piezomirror used in a feedback configuration to keep constant the phase of the interferometer. The feedback system is driven by a proportional, integral, derivative control software, and the stability degree is controlled by the reference signal coming from a standard test grating. A preliminary experimental characterization indicates that good control and stabilization of parasitic fluctuations of the interference pattern are obtained.
authors.affiliation: Liquid Crystals Laboratory, National Institute for the Physics of Matter, Center of Excellence, Arcavacata di Rende (CS), Italy.
authors.forename: Luciano
authors.initials: L
authors.lastname: De Sio
authors.forename: Roberto
authors.initials: R
authors.lastname: Caputo
authors.forename: Antonio
authors.initials: A
authors.lastname: De Luca
authors.forename: Alessandro
authors.initials: A
authors.lastname: Veltri
authors.forename: Cesare
authors.initials: C
authors.lastname: Umeton
authors.forename: Andrey V
authors.initials: AV
authors.lastname: Sukhov