Particle image velocimetry: improving fringe quality with a negative-mask method

Appl Opt. 1995 Apr 10;34(11):1763-8. doi: 10.1364/AO.34.001763.

Abstract

The photographic negative-mask method of neutralizing the diffraction-halo effect in speckle photography is applied to enhance the quality of Young's fringes obtained in particle-image-velocimetry studies. The improvement of the fringes achieved with the negative-mask method is compared with improvements by the commonly used method of analyzing a contact copy of particle-image-velocimetry specklegrams. Theoretical analysis and experimental results are presented.