PHYSICAL INTERPRETATION OF VIRTUAL RAYS

The method of virtual rays has been known for over three decades, and recent interest in the method has arisen in the context of diffraction theory. This method is based on postulates for which no rigorous phys ical explanation is provided. We show that the method of virtual rays can be derived rigorously from the pathintegral formalism pioneered by Feynman in the context of quantum mechanics. The free-space and perfe ctly conducting wedge Green's functions used in the virtual ray method are derived from the path-integral Aharonov-Bohm propagators. Physica l interpretations of the mathematical steps in the analysis are provid ed throughout. (C) 1997 Optical Society of America.