Angle-Dependent Reflectance of Laser-Produced Plasmas

The reflectance of planar targets irradiated by 400-mJ, 30-ps Nd: glass laser pulses was measured as a function of angle of incidence and polarization with an Ulbricht spherical photometer. At normal incidence we find reflectances > 0.6. The reflectance for $p$-polarized light has a minimum at an incidence angle of 20° to 30°; for angles greater than 60° total reflection occurs for both $s$- and $p$-polarized light. The results seem consistent with simulations.