The efficiency with which information may be recovered from a phase object is shown to be greater when the object is inserted into a laser cavity than when it is illuminated passively by the same laser. The parameters of both the laser and object which affect this efficiency are discussed. Examples of information processed in coherent, as well as in partially coherent, light are presented.
H. Wieder and R. V. Pole, "Reactive Optical Information Processing. II: Factors Affecting the Applicability and Efficiency of the Method," Appl. Opt. 6, 1761-1765 (1967)