Advanced Development of Fiber Coupled Diode Lasers

Recently, much effort has been made to develop semiconductor laser technology. As a result, the device technology has matured so that power levels, and lifetimes are more than adequate for many practical applications. Laser diode array bars are available which produce up to 100 wats per cm of optical power. With this impressive device capability more and more applications are emerging and the emphasis is now shifting to the optical and thermal management systems which can best take advantage of the high brightness and power levels. For optical management, one attractive option is fiber coupling. Fibers offer a simple, inexpensive, low loss method for delivering optical power in a way that preserves the intensity and brightness of the source and at the same time offers a wide range of architectural options for subsequent systems which spectrally, spatially or temporally reformat the power. For thermal control microchannel coolers have been demonstrated with thermal impedance less than .015 C/(W/cm2). SDL proposes to assess DoD and commercial applications for fiber coupled sources in the 50 to 100 Watt average power range and develop a design based on the 100 Watt bar, a 600 micron fiber link, and microchannel cooling.