Abstract

In the theoretical analysis of the light modes in optical resonators and laser beam propagation in a homogeneous medium the low-angle diffraction approximation is usually applied (see, for example, Kogelnic H.,Li T., Laser Beams and Resonators, Appl. Optics, 1966, v. 5, No. 10, p. 1550-1567). However, there exist some problems in which this approach is not valid, for example, ones concerning sharply focused wave beams, because they are not paraxial.

© 1996 IEEE