Method and device for the removal of material by means of laser pulses

摘要

The invention relates to a method for removing material by means of a laser, wherein a sequence of laser pulses is generated and an area of material to be machined is irradiated with the sequence of laser pulses. Methods of this kind are used to cut a number of different materials. One problem with this method is that thermal or mechanical damage occurs in the surroundings of the area being machined and causes impairment of areas of material that are not being machined. The invention solves this problem by the pulse energy of a single pulse in the sequence of laser pulses being lower than the laser pulse energy required to produce material removal using an isolated laser pulse in the region irradiated with the single laser pulse of the sequence of laser pulses.

主权项

1. A method for removing material by means of a laser, wherein a sequence of laser pulses is generated and an area of material to be machined is irradiated with the sequence of laser pulses,
characterized in that a pulse energy of each pulse in the sequence of laser pulses is lower than a laser pulse energy required to produce the removal of material by an isolated laser pulse in the area irradiated by a single pulse of the sequence of laser pulses, wherein the irradiated area is spatially overlapped by two consecutive laser pulses of the sequence of laser pulses to an extent of less than 50%, wherein each of the two consecutive laser pulses have a substantially similar duration and intensity, wherein a continuous ablation area is removed from the material by the sequence of laser pulses, wherein the material is removed through the accumulation of thermal energy over the two consecutive laser pulses, wherein an area that is not spatially overlapped by the two consecutive laser pulses is removed from the material through diffusion of the thermal energy over the irradiated area, and wherein a repetition rate of the two consecutive laser pulses is below 100 MHz.