title: Some opportunities for vibration analysis with time averaging in digital Fresnel holography.
abstract: Features offered by the combination of time averaging and digital Fresnel holography are investigated. In particular, we introduce the concept of the zero-crossing phase of Bessel fringes, which allows a highly contrasted determination of the dark fringes in the hologram. We discuss some particularities of the digital reconstruction and show how time-averaged digital holography can be used to study vibration drifts. Experiment results are presented in the case of a loudspeaker under a sinusoidal excitation; digital and analogical holography are also compared.
authors.affiliation: Ecole Nationale Supérieure d'Ingénieurs du Mans, rue Aristote, 72085 Le Mans 9, France. pascal.picart@univ-lemans.fr
authors.forename: Pascal
authors.initials: P
authors.lastname: Picart
authors.forename: Julien
authors.initials: J
authors.lastname: Leval
authors.forename: Denis
authors.initials: D
authors.lastname: Mounier
authors.forename: Samuel
authors.initials: S
authors.lastname: Gougeon