High Energy, Diode-Pumped, Nd:YAG Laser for Space-Based Lidar

Lidar systems are powerful tools for a wide range of remote sensing applications. These include precision distance measurements, target detection, designation, and imaging, and wind speed measurements. The transition of lidar technology into space will provide a powerful tool for defense and commercial applications. For space-based measurements, lasers with a near diffraction limited beam quality and pulse energies on the order of 1 J are often required. Higher repetition rates increase the data acquisition rate. We are proposing to investigate 1 µm laser designs that can provide 1 J/pulse at 100 Hz in a robust and compact package suitable for space. Our approach is based on an oscillator/amplifier design. The design incorporates diode-pumped, conductively cooled slabs as the gain media. The oscillator is an innovative telescopic ring resonator design that can achieve high beam quality and pulse energies on the order of 125 mJ. By starting with higher energy oscillator pulses we can achieve a more compact overall system. Proof of principle resonator measurements and scaling analysis have been performed in Phase I. The addition of amplifiers to achieve the final 0.5 -1 J output as well as the development of space-qualifiable packaging will occur in Phase II.