Quantitative characterization of potential energy landscape in holographic optical tweezers

We present a parallel calibration technique especially designed to evaluate the potential well spatial shape of multiple holographic optical tweezers. The basic principle is to extend the conventional unidirectional drag force method to a multi-axes one, associated with image processing. We then focus on the characterization of anisotropic distorted optical potential wells of holographic optical tweezers, where the distortion comes from optical aberrations and/or effects due to nearby ghost or regular traps. We also address the dependence of the diffraction efficiency with the trap position in a given traps pattern.