Characterizing focusing units for micromachining with ultrashort laser pulses

We investigate the focusing performance of optical tools for materials processing with ultrashort laser pulses. Here, focus distributions generated by high-NA microscope objectives and f-theta objectives are evaluated in terms of peak intensities and symmetry breaks when pulses of ≲ 100 fs are applied. With our simulations, we additionally examine the effects of spatial beam shaping and uncover associated spatio-temporal focusing phenomena, when diffractive optical concepts are used, for example, to shape customized non-diffracting beams or 3D-focus distributions.