title: Digital holographic interferometry with CO2 lasers and diffuse illumination applied to large space reflector metrology [Invited].
abstract: Digital holographic interferometry in the long-wave infrared domain has been developed by combining a CO(2) laser and a microbolometer array. The long wavelength allows large deformation measurements, which are of interest in the case of large space reflectors undergoing thermal changes when in orbit. We review holography at such wavelengths and present some specific aspects related to this spectral range on our measurements. For the design of our digital holographic interferometer, we studied the possibility of illuminating specular objects by a reflective diffuser. We discuss the development of the interferometer and the results obtained on a representative space reflector, first in the laboratory and then during vacuum cryogenic test.
authors.affiliation: Centre Spatial de Liège, Université de Liège, Avenue du Pré Aily, Angleur (Liège) B-4031, Belgium. mgeorges@ulg.ac.be
authors.forename: Marc P
authors.initials: MP
authors.lastname: Georges
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Vandenrijt
authors.forename: Cédric
authors.initials: C
authors.lastname: Thizy
authors.forename: Yvan
authors.initials: Y
authors.lastname: Stockman
authors.forename: Patrick
authors.initials: P
authors.lastname: Queeckers
authors.forename: Frank
authors.initials: F
authors.lastname: Dubois
authors.forename: Dominic
authors.initials: D
authors.lastname: Doyle