Application Of High-Speed Photography To Time-Resolved Wavefront Measurement

For long-pulse (150 microseconds), side-pumped lasers, such as dye or reactor-pumped lasers, a significant transverse index gradient can develop. In order to design an appropriate laser resonator for efficient power extraction, a detailed space- and time-resolved determination of the index perturbation is required. We have applied high-speed photography to the measurement of wavefront errors in a pulsed laser gain region using a fast framing camera. We utilized both a derivative of a Hartmann test technique and a shearing interferometer, with good agreement between the two. The measured wavefronts have a predominantly parabolic index shape except near the walls, with a roughly linear time dependence during the pumping pulse.© (1988) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.