The purpose of active imaging systems is to provide discrimination at long ranges independently from the surrounding illumination by using and controlling its own light source. Parameters such as the Doppler shift for coherent devices, the range, or the intensity of the light back scattered by objects have already been used to encode images. However, another parameter characterizing the electromagnetic field can help to discriminate the target: its polarization. In this paper we demonstrate that images resulting from the analysis of the polarization of light can offer better contrasts than classical images encoded by the intensity of light back-scattered. The emitting part of the imaging polarimeter built at CREOL (Polarization State Generator) is a doubled YAG pulsed laser with external polarization controllers. At the receiving part, the Polarization State Analyzer separates the incoming light so as to provide two crossed polarized images of the target. These images are acquired simultaneously by two high-resolution progressive scan digital cameras controlled by a computer. Afterwards, the computer processes the acquired data and displays two new images encoded by polarization parameters (depolarization ratio for example). In several examples and experiments, the influence of the geometry of the target (roughness, shape) on the incident state of polarization will be discussed.
