When the performance of an optical system is evaluated by tracing rays from a point source through the system, it is necessary in some cases to use rays which effectively transport equal amounts of energy per unit time (isoenergetic rays). The procedure given in the optical literature for generating isoenergetic rays is to distribute the ray intersections with the entrance pupil with uniform density per unit area. It is shown here that this procedure is not rigorously correct, and a correct procedure for generating isoenergetic rays is presented.
© 1985 Optical Society of America
J. W. Foreman, Jr., "Isoenergetic rays in ray trace programs. 1: Generation of isoenergetic rays," Appl. Opt. 24, 1209-1216 (1985)