Thomas Schwander

High stability, fast tunable single frequency laser source for space based lidar applications

This paper describes the design and performance of the TESAT Reference Laser Head, acting as the frequency reference for the ALADIN Transmit Assembly (TXA) for the ESA AEOLUS satellite. First measurements of short time frequency stability (130 kHz rms over 360 sec) and digitally controlled coarse and fine step tuning functionality will be presented.

Space qualified laser sources

Tesat-Spacecom has developed a series of fiber coupled single frequency lasers for space applications ranging from onboard metrology for space borne FTIR spectrometers to step tunable seed lasers for LIDAR applications. The cw-seed laser developed for the ESA AEOLUS Mission shows a 3* 10-11 Allen variance from 1 sec time intervals up to 1000 sec. Q-switched lasers with stable beam pointing under space environments are another field of development. One important aspect of a space borne laser system is a reliable fiber coupled laser diode pump source around 808nm. A dedicated development concerning chip design and packaging yielded in a 5*106h MTTF (mean time to failure) for the broad area emitters. Qualification and performance test results for the different laser assemblies will be presented and their application in the different space programs.

New 808 nm high power laser diode pump module for space applications

New pump module concepts had to be developed for space borne applications, because a simple transformation of terrestrial solutions to space requirements was often not useful. A planar approach has been chosen, which prevents inherent draw-backs of stacks.