title: Full-field vibrometry with digital Fresnel holography.
abstract: A setup that permits full-field vibration amplitude and phase retrieval with digital Fresnel holography is presented. Full reconstruction of the vibration is achieved with a three-step stroboscopic holographic recording, and an extraction algorithm is proposed. The finite temporal width of the illuminating light is considered in an investigation of the distortion of the measured amplitude and phase. In particular, a theoretical analysis is proposed and compared with numerical simulations that show good agreement. Experimental results are presented for a loudspeaker under sinusoidal excitation; the mean quadratic velocity extracted from amplitude evaluation under two different measuring conditions is presented. Comparison with time averaging validates the full-field vibrometer.
authors.affiliation: Laboratoire d'Acoustique de l'Université du Maine, Unite Mixté de Recherche, Centre National de la Recherche Scientifique, 6613, Avenue Olivier Messiaen, 72085 Le Mans 9, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Leval
authors.forename: Pascal
authors.initials: P
authors.lastname: Picart
authors.forename: Jean Pierre
authors.initials: JP
authors.lastname: Boileau
authors.forename: Jean Claude
authors.initials: JC
authors.lastname: Pascal