Laser induced damage to mirrors at two pulse durations: Technical Report No. 2, Period 31 December 1971 to 30 June 1972 /

The damage thresholds of eight, multiple layer dielectric, 95 percent reflecting mirrors have been measured for single pulses of 20 nsec and 20 psec duration. In both sets of measurements the pulse energy, an oscilloscope trace of the pulse, and the beam's transverse energy density profile at the surface being damaged are recroded for each shot. The variation of the threshold from mirror to mirror and as a function of pulse duration, beam radius, and appearance under microscopic examination is discussed in the context of possible damage mechanisms. (Author).Research supported by the Air Force Cambridge Research Laboratories, Air Force Systems Command, United States Air Force, L.G. Hanscom Field, Bedford, Massachusetts.Optical Physics Laboratory Project 6100.AD0751265 (from http://www.dtic.mil)."25 July 1972."Includes bibliographical references (page 27).The damage thresholds of eight, multiple layer dielectric, 95 percent reflecting mirrors have been measured for single pulses of 20 nsec and 20 psec duration. In both sets of measurements the pulse energy, an oscilloscope trace of the pulse, and the beam's transverse energy density profile at the surface being damaged are recroded for each shot. The variation of the threshold from mirror to mirror and as a function of pulse duration, beam radius, and appearance under microscopic examination is discussed in the context of possible damage mechanisms. (Author).Mode of access: Internet