Partially Overlapped Dual Laser Beams to Reduce Ablation Craters

We present our experimental ablation results for partially overlapped dual nanosecond laser beams (PO-DB) on metal and glass surfaces. Numerical simulations are performed to evaluate the crater reduction potential of the PO-DB setup. Damage probability experiments proved the collaboration of two beams within the overlap region. Bright-field and three-dimensional profile measurements verify the reduced ablation area from the proposed PO-DB scheme. Laser-induced plasma is generated when transparent glass is ablated. Atomic emission of Na I (\sim589.95 nm) shows comparable signal between the PO-DB set and the traditional single laser beam set. The proposed PO-DB ablation mechanism could also be applied to femtosecond laser systems.