100 kHz diffraction-limited femtosecond laser machining
Abstract
We demonstrate active and adaptive wavefront correction of a 100 kHz amplified femtosecond laser chain, and investigate the subsequent improvement for micromachining applications. Thanks to a non-pixelated liquid crystal modulator, phase-front distorsions are decreased down to landa/15 peak-valley and landa/100 rms. Clean 1.7 µm diffraction-limited micro-holes are obtained, both on low-threshold metallic and high-threshold dielectric materials. This high beam quality femtosecond source enables diffraction-limited high-speed micromachining.