Effect of multiple reflections on the design of an elliptic cavity for solid state lasers

The effects of multiple reflections in an elliptic reflector are investigated. The emphasis is on matching the absorption spectrum of laser crystals to laser pumps by increasing the effective absorption coefficient in areas of low absorption. It is shown that in an ideal case the pump power that would normally be lost, because of a low absorption coefficient of the crystal, can be regained by multiple reflections from a highly reflective elliptic cylinder. This gain is somewhat reduced by refraction of the rays by the crystal and flashlamp. An optimum condition for minimizing the refraction losses is derived including the effects of multiple reflections.