US Patent 10429243 Space-based sodium Lidar instrument and method of operation

The present invention relates an apparatus and method for measuring range-resolved atmospheric sodium temperature profiles using a space-based Lidar instrument, including a diode-pumped Q-switched self-Raman c-cut Nd:YVO4 laser with intra-cavity frequency doubling that could produce multi-watt 589 nm wavelength output. The c-cut Nd:YVO4 laser has a fundamental wavelength that is tunable from 1063-1067 nm. A continuous wave narrow linewidth diode laser is used as an injection seeder to provide single-frequency grating tunable output around 1066 nm. The injection-seeded self-Raman shifted Nd:VO4 laser is tuned across the sodium vapor D2 line at 589 nm. In one embodiment, a space-qualified frequency-doubled 9 Watt at 532 nm wavelength Nd:YVO4 laser, is utilized with a tandem interference filter temperature-stabilized fused-silica-etalon receiver and high-bandwidth photon-counting detectors.