Munich, Germany—Once while giving a lecture I wondered, aloud, why all industrial lasers were designed to be horizontal. Marius Jurca of My Optical Systems GmbH (MYOS—Kahl am Main, Germany) must have heard me because his company introduced a unique, high-powered diode laser that can deliver the beam directly in a vertical attitude. This laser seemed to be one of the "must see" exhibits at this year's LASER 2003.
The Ringfocus laser head employs a number of single diode bars (in the photo, 19 single-bar emitters, producing 40-60 W each are used), arranged in an orbital symmetrical manner such that their output beams are directed via a parabolic mirror and a reimaging mirror to converge at a focus point on a workpiece. And the resulting spot is uniform in power density. The laser head has an annulus in the optical axis that allows the feeding of cladding materials or assist gases coaxial with the beam. The total optical loss, due to beam shaping and focusing is less than 10 percent.
What's the advantage? A long working distance, >150 mm, means that the lightweight (12kg) focus head can be moved easily, under programmed control, over a clamped part. A small diameter focus spot, 0.8 mm, means high power density is achievable from the diodes. High output powers, scalable to 5 kW, at preselected wavelengths from 808 to 980 nm, offers users the ability to work a variety of normally reflective metals, without concern for back reflections. And the unit can be run CW or pulsed (up to 50 kHz). The single-bar diodes from Spectra Physics (Tucson, AZ) offer up to 10,000 hours of life, making this laser ideal for low-maintenance factory installations.
MYOS sees applications in welding with filler metal addition and powder-feed cladding for metal build-up as key opportunities. The 1.5kW unit shown in the photo is installed at the Fraunhofer IWS (Dresden, Germany) for this type of application. The Ringfocus laser is also expected to find use in hardening, soldering, deburring, selective ablation and other applications.
On the other hand, one of the most important markets for this laser will be the optical pumping of solid-state lasers.
Access the company's Website, www.myos.de, for more details.
—DAB