Percussion drilling with nanosecond laser-pulse bursts, instead of single nanosecond pulses, has advantages for metal machining, according to researchers from Multiwave Photonics (Maia, Portugal) and TASC (Albuquerque, NM). The bursts, with a wavelength of 1064 nm, contain up to 14 pulses and repetition frequencies of tens of megahertz per burst. The individual pulsewidths can be varied between 10 and 200 ns; the bursts can occur one at a time or be emitted at up to 500 kHz rates.
The light source, a master-oscillator power-amplifier fiber laser, can be externally triggered and has 12 kW peak power. Each effective pulse can contain controllable multipulse bursts as a result of modulating the laser-diode pump; this is referred to as dynamic pulsing. A 25-µm-thick stainless-steel sheet was chosen as the drilling material. As the number of pulses per burst was increased, the number of bursts required to drill through the sheet dropped—for example, from 35 bursts with single pulses down to 4 bursts with each divided into 10 pulses. The edges of the holes resembled those produced by a very high-repetition-rate modelocked laser.
Contact Sami T. Hendow at [email protected].
Gail Overton | Senior Editor (2004-2020)
Gail has more than 30 years of engineering, marketing, product management, and editorial experience in the photonics and optical communications industry. Before joining the staff at Laser Focus World in 2004, she held many product management and product marketing roles in the fiber-optics industry, most notably at Hughes (El Segundo, CA), GTE Labs (Waltham, MA), Corning (Corning, NY), Photon Kinetics (Beaverton, OR), and Newport Corporation (Irvine, CA). During her marketing career, Gail published articles in WDM Solutions and Sensors magazine and traveled internationally to conduct product and sales training. Gail received her BS degree in physics, with an emphasis in optics, from San Diego State University in San Diego, CA in May 1986.