Abstract
We propose a new method for focus tracking during the recording of a sequence of digital holograms while the sample experiences axial displacement. Corrected reconstruction distances can be automatically calculated, and well-focused amplitude and phase-contrast images can be obtained for each digitized hologram. The method is demonstrated for inspection of microelectromechanical systems subjected to thermal load. The method can be applied as a quasi-real-time procedure.
© 2003 Optical Society of America
Full Article | PDF ArticleMore Like This
Pietro Ferraro, Sergio De Nicola, Giuseppe Coppola, Andrea Finizio, Domenico Alfieri, and Giovanni Pierattini
Opt. Lett. 29(8) 854-856 (2004)
Pascal Picart, Julien Leval, Denis Mounier, and Samuel Gougeon
Opt. Lett. 28(20) 1900-1902 (2003)
W. Xu, M. H. Jericho, H. J. Kreuzer, and I. A. Meinertzhagen
Opt. Lett. 28(3) 164-166 (2003)