OPTICAL MEDIA AND TARGET CHARACTERIZATION BY MUELLER MATRIX DECOMPOSITION

Laser imaging set-ups permit characterization of the vectorial nature of the optical wave which is transmitted by a medium or reflected by a target, from polarimetric formalisms such as Jones or Stokes-Mueller calculi. When the Mueller matrix M of targets (or media) is experiment ally determined, information about the polarizing and depolarizing pro perties can be obtained from a Mueller-Jones matrix, which operation r equires knowledge of the experimental uncertainties in the elements of M. We will discuss the possibility of a polar decomposition of the ex tracted Mueller-Jones matrix. We then obtain the product of a Hermitia n matrix and a unitary matrix, which can be associated with it, for a polarization transformer, with an elliptical partial polarizer and a p ure elliptical retarder respectively. Classification of a target is de duced from its polarimetric characteristics (depolarization, polarizin g and retardation properties). Experimental Mueller matrices of polari zation transformers (media or targets) are provided and analysed by th is method in order to characterize the physical behaviour of these opt ical systems with respect to polarization phenomena.