Aliasing-free speckle propagation: Critical sampling rules.

Speckle generation is a well-known optical phenomenon that is produced when coherent light is scattered from an optically rough surface. Due to its complex random nature it is generally studied using statistical methods. It plays an essential role in non-destructive testing and metrology under coherent illumination. Despite being well understood analytically (delta correlated model), it is difficult to simulate the propagation of such speckle fields numerically, due to replicas that arise from the numerical sampling process. Also, an appropriate space-bandwidth product for a delta correlated complex field cannot be properly defined. Here sampling conditions are defined that allow us to numerically propagate a speckle field without aliasing. With this numerical framework we examine the important problem of phase retrieval.