Berlin, Germany -- DirectPhotonics Industries GmbH has signed a worldwide patent license agreement with two of the Fraunhofer laser groups: the Center for Laser Technology (CLT) in Plymouth, MI, and the Institute for Laser Technology (ILT) in Aachen, Germany. The patents collectively cover high-brightness direct-diode lasers incorporating a building-block design based on optically stacked high-power single emitters.
Two of the patents from Fraunhofer CLT involve an exclusive license: a high-power laser diode array (US #7,751,458) and high-power diode laser having multiple emitters (US #8,213,479). A third patent licensed from Fraunhofer ILT is nonexclusive, involving a "device for providing the cross-section of the radiation emitted by several solid-state and/or semiconductor diode lasers with a specific geometry" (US #6,124,973/DE 197 80 124 B4).
"This patent suite has important technology implications since it enables, for the first time ever, the use of direct high power laser diodes for materials processing applications, eliminating the need of conventional laser resonators," stated Wolfgang Gries, DirectPhotonics's founder and CEO.
DirectPhotonics is working on high-brightness diode lasers at power levels of hundreds of watts and even multi-kilowatt output power. "The core technologies are based on patented diode modules and dense spectral combining," two areas showing the most promise for improving diode laser brightness, pointed out Prof. Reinhart Poprawe, director of Fraunhofer ILT.
Direct-diode lasers are seen by many as the future of industrial lasers, with the caveat that beam quality still needs improvement. Laserline and Coherent's Highlight line (née Nuvonyx) have had some success in this area. In the wings are DirectPhotonics and startup TeraDiode (with technology from MIT), expected to debut relatively high beam quality direct-diode lasers sometime in 2013.
Robust beam transformation system for fiber-coupled multi-kW lasers. (Source: Fraunhofer ILT)