We demonstrate experimentally a novel technique for characterizing transverse spatial coherence by using the Wigner distribution function. The method is based on the measurement of interference between a pair of rotated and displaced replicas of the input beam with an area-integrating detector, and it provides an optimal signal-to-noise ratio in regimes when array detectors are not available. We analyze the quantum-optical picture of the presented measurement for single-photon signals and discuss possible applications in quantum information processing.
© 2003 Optical Society of America
Eran Mukamel, Konrad Banaszek, Ian A. Walmsley, and Christophe Dorrer, "Direct measurement of the spatial Wigner function with area-integrated detection," Opt. Lett. 28, 1317-1319 (2003)