Design of continuous surface-relief phase plates by surface-based simulated annealing to achieve control of focal-plane irradiance

High-performance phase plates are of vital concern for controlling the far-field irradiance of laser-fusion systems. Several designs for solving this difficult problem have been reported in Optics Letters [e.g., S. N. Dixit et al., Opt. Lett. 19, 417 (1994)]. We report a surface-based form of simulated annealing that significantly improves the irradiance control while eliminating the high-scatter problems that have plagued other methods. copyright 1996 Optical Society of America