Methods of Interaction Field Extension for Precision Highspeed Femtosecond Laser Processing of Transparent Materials


The results of experiments on the study of methods of the focal volume elongation in the direction of the propagation of femtosecond laser pulses are given. The lengthening of the focal volume due to linear effects - interface spherical aberration, beam self-diffraction, and nonlinear effects - Kerr self-focusing is demonstrated. The conditions and reasons for the formation of extended filamentary micromodifications with diameters about 2 μm and a length of more than 100 μm in polycarbonate samples using different methods of extending the interaction region are determined.

Keywords: femtosecond laser, microstructures, microprocessing, photodegradation, filamentation.

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