High average power Yb:CaF2 femtosecond amplifier with integrated simultaneous spatial and temporal focusing for laser material processing.

A watt level, 10-kilohertz repetition rate chirped pulse amplification system that has an integrated simultaneous spatial and temporal focusing (SSTF) processing system is demonstrated for the first time. SSTF significantly reduces nonlinear effects normally detrimental to beam control enabling the use of a low numerical aperture focus to quickly treat optically transparent materials over a large area. The integrated SSTF system has improved efficiency compared to previously reported SSTF designs, which combined with the high repetition rate of the laser, further optimizes its capability to provide rapid, large volume processing.