A new laser system for use of differential absorption lidar (DIAL) in measurements of tropospheric water vapor and temperature is introduced. This system operates in the 720–780-nm region and is configured as an alexandrite ring laser injection seeded by a cw Ti:sapphire ring laser. This combination provides for the necessary narrow-bandwidth, high-frequency stability and excellent spectral purity. A bandwidth of <5.0 × 10-3 cm-1, a frequency stability of 2.1 × 10-3 cm-1 rms, and a spectral purity of 99.995% at 726 nm have been achieved during extended periods of operation. A comparison of a DIAL water-vapor measurement with a radiosonde in the boundary layer between 500 and 2000 m was performed. The maximum deviation between the humidity profiles is 15%, the standard deviation 1.6%, and the difference between the mean values 1%.
© 1995 Optical Society of America
V. Wulfmeyer, J. Bösenberg, S. Lehmann, C. Senff, and St. Schmitz, "Injection-seeded alexandrite ring laser: performance and application in a water-vapor differential absorption lidar," Opt. Lett. 20, 638-640 (1995)