Target damage studies with a pulsed CO2 TEA laser facility

A pulsed CO2 TEA laser facility had been developed and applied to the measurement of surface damage thresholds of several practical materials, inclusive of ZnSe and A/R-coated Ge. The pulse shape of optical emission during LSA wave initiation has been recorded on oscillograms. Among the principal conclusions is that polycrystalline chemical vapor deposited ZnSe has a higher damage threshold than polycrystalline hot press ZnSe; also LSA wave formation may initiate prior to surface damage on ZnSe and Al foil, whereas damage occurs first on Plexiglas.