Interferometric vibration detection using fringe visibility quantifier

Abstract

A technique for automated detection of vibrations using focus analysis of interferograms is demonstrated experimentally. Digital camera is used to record live interferograms from a Mach-Zehnder interferometer constructed on a vibration-isolation optical table. Occurrences of transient events that induce vibrations in the setup alter the interferogram fringe visibility. Statistical focus measures are found to be sensitive to fringe visibility yielding signal spikes corresponding to the event occurrences. The technique can be applied in the detection of seismic vibration, acoustic noise and air turbulence.