08 Jul 2010
Military contractors Lockheed-Martin and Raytheon win funding under the US Army’s Robust Electric Laser Initiative.
The US Department of Defense has awarded long-term contracts to Raytheon and Lockheed-Martin aimed at developing a 100kW weapons-class laser system.
Under the Robust Electric Laser Initiative (RELI), and contracted by the US Army Space Missile Defense Command in Huntsville, Alabama, Lockheed was awarded $14.7 million on June 28. Raytheon received $9.1 million on June 24.
Lockheed’s MS2 Integrated Defense Technologies unit will work on the project, which has an estimated completion date of December 2016.
The idea behind RELI is to produce a 25kW laser that can then be scaled to 100kW output and used to shoot down enemy missiles or similar. Northrop Grumman, which is also contracted for $8.7 million under the project, is using a proprietary beam-combining technique based on a two-dimensional diffractive optical element to ramp the laser output towards 25kW.
While fiber lasers are one option being followed to produce weapons-class high-power lasers, Raytheon’s approach under RELI is based on its planar waveguide (PWG) technology.
PWG lasers are high aspect ratio sandwich-type structures with a high-index active core surrounded by lower-index claddings. Raytheon has described the structure as essentially a one-dimensional fiber in which the thin transverse axis is guided and the wide transverse axis is unguided.
Crucially, the guiding structure of the PWG allows high pump absorption efficiency. The high aspect ratio also offers a suitable geometry for efficient cooling, and, a 100kW-class PWG should only measure 30-40cm in length.
The guided propagation of the signal beam in the thin core of a PWG also cancels out the thermal lensing effect, permitting a wide operating power range with low optical distortion.
As part of the latest contract award, Raytheon is expected to demonstrate integrated operation of the system at the high-energy laser (HEL) test facility in White Sands Missile Range in New Mexico.
With the development taking place in El Segundo, California, work is expected to be completed in June 2017.