In the case of fluorescence investigation of systems, which are isotropic in the macro scale but anisotropic in the micro scale, a Bayesian approach to an inverse problem allows finding distributions of model parameters. Next, this approach provides capacity to ascertain, whether the aligning potential alters during an electronic excitation of the fluorescence probe. The usage of the synthetic data set allows to specify an extent of a priori information necessary to a description of the data. As a numerical basement for Bayesian calculations the Differential Evolution Markov Chain method is employed. (C) 2013 Elsevier B.V. All rights reserved.