Microcutting of glass with high ablation efficiency by means of a high power ps-pulsed NIR laser

Microcutting of glass through ultrafast lasers represents a process more and more employed in many industrial fields, among which touchscreen displays for electronic devices. The main disadvantage is the low processing speed that does not meet the industrial requirements. In this work, a ps-pulsed NIR laser with 200 W average power was employed for cutting of thick soda-lime glass with a relatively high thickness of 1 mm submerged in water. The cut evolution with respect to the number of passes and the quality of cut kerf were analysed by considering different levels of pulse repetition rate, pulse energy and scan speed. The results show a considerable influence of the scan speed on the ablation efficiency and surface roughness, because of the thermal accumulation given by the pulse overlap. Complete cut of 1 mm-thick glass was achieved at 400 kHz, 360 μJ, with speed from 0.5 m/s to 3 m/s and number of scans from 300 to 1900 respectively. The results showed that the use of high power ps-pulsed NIR laser can provide high material removal efficiency up to 600 µm3/pulse at 0.5 mm thickness and up to 300 µm3/pulse at 1 mm thickness.