Dynamic of speckle cluster formation

A. LENCINA; M. TEBALDI; P. VAVELIUK; N. BOLOGNINI

Waves in complex and random media

Taylor and Francis

Año: 2006 p. 1 - 10

1745-5030

In this work, we analyze the speckle cluster structure generated when a coherently illuminated diffuser is imaged by introducing a multiple apertures pupil mask in front of the lens plane. We demonstrate that the speckle cluster originates from the complex modulation produced inside each speckle which is generated by multiple interferences among the apertures. The auto-correlation function of the intensity distribution for a multiple aperture pupil arrangement is calculated and it is demonstrated that coincides with the intensity corresponding to a single scattering element. This result allows analyzing the dynamics of the cluster formation based on a single scattering element. This analysis permits to determine the pupil mask parameters that control the cluster behavior and therefore the condition to obtain a high repetitive cluster structure that we define as “regular cluster”. The theoretical simulations based on the random walk model are in agreement with the experimental results supporting the validity of our approach.