Stress control during ultrashort pulses laser for glass machining

Abstract

Requirements on glass manufacturing with exceptionally high mechanical strength triggered development of new laserbased processing methods. Localized modifications produced by ultrashort pulsed lasers are attractive but may lead to micro-crack generation in glass. Aiming to control stresses during volumetric material modifications, we have studied the effect of pulse duration experimentally. Bessel beam shapes with arbitrary conical angles have been generated using a programmable spatial light modulator (SLM), while stresses have been monitored using time-resolved optical transmission and cross polarized microscopy. Pulse duration variation influences mechanical stress in the laser glass interaction, and we found the optimized pulse duration exists in the laser glass machining by pump-probe microscopy.

Non-disruptive Bessel-beam array generation for high-throughput shadow mask laser patterning

“…The use of ultrashort with variable pulse (~300 fs to 10 ps) duration is required to achieve efficient modification with low non-linear effects resulting in broadening of the modification size. The pulse duration ~5 ps allows to localize energy within the small spots with minimal size around ~1 µm defined by laser wavelength [11]. Good uniformity of processed microchannel is obtained over the large area with no macrocracks even when the shot pitch is maintained around 10 µm.…”