High efficiency laser designs for airborne and space-based lidar remote sensing systems

The increasing use of lidar remote sensing systems in the limited power environments of unmanned aerial vehicles and satellites is motivating laser engineers and designers to put a high premium on the overall efficiency of the laser transmitters needed for these systems. Two particular examples upon which we have been focused are the lasers for the ICESat-2 mission and for the Laser Vegetation Imaging Sensor-Global Hawk (LVIS-GH) system. We have recently developed an environmentally hardened engineering unit for the ICESat-2 laser that has achieved over 9 W of 532 nm output at 10 kHz with a wall plug efficiency to 532 nm of over 5%. The laser has a pulse width of <1.5 ns and an M-2 of <1.5. For the LVIS-GH lidar, we recently delivered a 4.2 W, 2.5 kHz, 1064 nm laser transmitter that achieved a wall plug efficiency of 8.4%. The laser has a pulse width of 5 ns and an M-2 of 1.1 We provide an overview of the design and environmental testing of these laser transmitters.