Method and device for laser processing of transparent materials

Abstract

The invention is related to fabrication of transparent materials by means of ultra-short laser pulses. Method to fabricate materials transparent in most part to laser wavelength comprises forming non-centrosymmetric, non-diffracting beam by optical element that contains at least two zones of birefringent structures changing Pancharatnam-Berry Phase according to the rule specific for that particular zone. The distribution of energy, phase and polarization depends on parameters of light approaching said element. Pulse energy is selected to employ main maximum of distribution to form voids elongated in desired direction while side maxima form changes of chemical character between damages from adjacent pulses. Void damages and zones of chemical changes form desired cut line. The workpiece prepared in said manner is placed in chemically aggressive solution, in which zones affected by laser light are dissolved much faster than non-affected ones. This enables achieving cuts with aspect ration up to 1/50.