Stress control during ultrashort pulses laser for glass machining

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.