The aim of this work is to understand the effects of the shrinkage phenomenon in H-PDLC reflection gratings trough the real time analysis of their transmission spectra during the recording process. The real time spectroscopic analysis of the samples showed a light intensity dependent free-radical polymerization indicated by a quick growth of the reflection peak whose corresponding diffraction efficiency, measured at normal incidence, is in the range 40%-45% depending on the photopolymerization conditions. An optical shrinkage corresponding to a 4.3% displacement of the reflected wavelength from the expected value has been detected. This value of the shrinkage is in agreement to that mesaured in similar system.
Optical properties of organic-based periodic structures / Lucchetta, Daniele Eugenio; Vita, Francesco; R., Castagna; Francescangeli, Oriano; Simoni, Francesco. - In: PROGRESS IN BIOMEDICAL OPTICS AND IMAGING. - ISSN 1605-7422. - 6654:(2007), p. 66540M-1.
Optical properties of organic-based periodic structures
LUCCHETTA, Daniele Eugenio;VITA, Francesco;FRANCESCANGELI, ORIANO;SIMONI, Francesco
2007-01-01
Abstract
The aim of this work is to understand the effects of the shrinkage phenomenon in H-PDLC reflection gratings trough the real time analysis of their transmission spectra during the recording process. The real time spectroscopic analysis of the samples showed a light intensity dependent free-radical polymerization indicated by a quick growth of the reflection peak whose corresponding diffraction efficiency, measured at normal incidence, is in the range 40%-45% depending on the photopolymerization conditions. An optical shrinkage corresponding to a 4.3% displacement of the reflected wavelength from the expected value has been detected. This value of the shrinkage is in agreement to that mesaured in similar system.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.