Optical Resonator Modes—Circular Reflectors of Spherical Curvature*

Modes in an optical resonator formed by two reflectors of generally dissimilar spherical curvature and circular shape are studied. The non-Hermitian Fredholm integral equation, whose solutions are the modes, is transformed into an equivalent matrix equation using a technique based upon the work of E. Schmidt. Mode losses, patterns, phases, and resonances are calculated for a moderately large Fresnel number and various “low-loss” and “high-loss” configurations. The results are compared with those derived by other methods.