Three-dimensional clustered speckle fields: Theory, simulations and experimental verification

A. LENCINA; J.P. STAFORELLI; P. SOLANO; J.M. BRITO; M. TEBALDI; N. BOLOGNINI

PHYSICAL REVIEW A - ATOMIC, MOLECULAR AND OPTICAL PHYSICS

AMER PHYSICAL SOC

Año: 2010

1050-2947

A speckle pattern appears when a coherent light source is re°ected or transmitted by a diffuser. Clustered speckle patterns appear when a coherently illuminated diffuser is imaged through a multiple aperture pupil mask attached to a lens. The clusters originate by the modulation that the pupil mask exerts over the original pattern. In this paper, a three-dimensional (3D) approach for the clustered speckles ¯eld after the lens is presented. Also, we consider the possibility of attaching a multiple aperture mask to the di®user, which allows a more general description. A proper choice of these masks permits one to obtain clustered speckles at the focal plane, the image plane or intermediate planes, expanding the possibilities to simulate clustered speckles in other places not previously done. The approach is validated by experimental results obtained from an optical tweezers setup and compared with simulations under di®erent conditions. Results enable a proper description of the intensity distribution features of these types of ¯elds, enhancing the possibility of their use for different applications through tailoring the patterns with appropriate masks . Some aspects of the possible uses of clustered speckle in optical tweezers, atom trapping, photorefractive register and speckle metrology are revised.