It is known that the degree of polarization of a light beam is, in general, different at different points in space. In this paper we show that there is a class of quasi-homogeneous sources which generate beams whose degree of polarization does not change as the beam propagates. © 2008 Elsevier B.V. All rights reserved.
Zhao, D., & Wolf, E. (2008). Light beams whose degree of polarization does not change on propagation. Optics Communications, 281(11), 3067–3070. https://doi.org/10.1016/j.optcom.2008.02.006