Thermal transient effects in repetitively pulsed flashlamp-pumped yag:nd and yag:nd, lu laser material.

Measurements have been made of the change of the optical pathlength due tothermal transient effects of two laser rod materials: YAG:Nd and YAG:Nd, Lu. These optical distortion measurements were studied as a function of flashlamp input energy level, coolant temperature, and pulse repetition frequency. Experimental data were obtained by passing a collimated He-Ne probe beam through the flashlamp pumped laser rod and recording the detector output as a function of time. The data show a significant difference between YAG:Nd and Lu co-doped YAG:Nd with respect to thermal transient effects. Using existing theory, results of calculations that predict the thermal effects are also presented for comparison with the experimental observations.