Optical Resonators in the Unstable Region

Abstract

The spectrum of characteristic oscillation frequencies and modal losses for spherical mirror opticalresonators is derived in an approximation equivalent to geometrical optics. This is a significant approximation for unstable or high loss configurations when the Fresnel number is large. The analysis is based on the scalar integral equations of Fox and Li and agrees with the known result for the dominant mode losses in the geometrical optics limit.