Abstract

State of drying paint is monitored from the dynamic behaviors of images reconstructed by phase-shifting digital holography. For quantitative analysis cross-correlation coefficient of complex amplitude, named here, coherence factor, between successive frames with an interval of 20 s. Its modulus shows variation indicating the random dynamic behavior of the paint surface, while its phase is apparently related with the change of paint thickness. In the dried state they reach stationary values. The modulus has been shown to relate to the degree of speckle correlation in the model of Gaussian random process.

© 2007 Optical Society of America