METHOD OF FICTITIOUS SOURCES AS APPLIED TO THE ELECTROMAGNETIC DIFFRACTION OF A PLANE-WAVE BY A GRATING IN CONICAL DIFFRACTION MOUNTS

Starting from the Maxwell equations, we solve the problem of the diffr action of a plane wave by a grating of finite conductivity, assuming t hat the incident wave vector is not orthogonal to the grooves. We make use of the method of fictitious sources, and the diffraction problem is thus reduced to two canonical problems: (1) the computation of the electromagnetic field radiated in free space by known sources and (2) the least-squares problem. The algorithm that we propose was implement ed on an IBM 530 computer, and some numerical results are given by way of illustration. (C) 1996 Optical Society of America