METHOD AND APPARATUS FOR MATERIAL PROCESSING USING MULTIPLE FILAMENTATION OF BURST ULTRAFAST LASER PULSES

摘要

A method of drilling multiple orifices in and texturing a substrate is disclosed and includes the following steps. Ultrafast laser pulses are passed through a beam splitting diffractive optical element and then multiple beams are passed through a distributive-focus lens focusing assembly. The relative distance and/or angle of said distributive-focus lens focusing assembly in relation to the laser source is adjusted focusing the pulses in a distributed focus configuration creating a principal focal waist and at least one secondary focal waist. The fluence level of the at least one secondary focal waists is adjusted such that it is or they are of sufficient intensity and number to ensure propagation of multiple filaments in the substrate. Photoacoustic compressive machining is performed and forms multiple volume(s) within the substrate.