DIAL hygrometer based on powerful laser diodes: calibration function and modulation of laser radiation

Abstract

Abstract A differential absorption lidar method utilizing the spectral and energetic properties of high-power, pulsed laser diodes for remote sensing of atmospheric humidity is reported. The laser radiation of selected complementary laser diodes is multiplexed in dual spectral channels centered at optimal wavelength of 0.86µm and 0.911µm. Humidity profiles are retrieved integrating multiple resonance lines in the tunable range within the absorption spectrum of water vapor. The integral spectrum is less affected by the variable atmospheric pressure and temperature, which is an essential advantage allowing direct and reliable DIAL measurement.