• Edge-technique lidar system makes high-accuracy wind measurements

    A ground-based incoherent Doppler lidar system uses the edge of a high-resolution spectral filter to measure wind speed with an accuracy of 10-25 cm/s and a spatial resolution of 15-30 m, a significant improvement over present methods. The edge filter measures the frequency of a small portion of the pulsed 1.06-µm output from a Nd:YAG laser, while the major portion of the output is tuned so that the laser wavelength is spectrally located on the stee¥edge of the filter. Because of the ste
    April 1, 1995

    A ground-based incoherent Doppler lidar system uses the edge of a high-resolution spectral filter to measure wind speed with an accuracy of 10-25 cm/s and a spatial resolution of 15-30 m, a significant improvement over present methods. The edge filter measures the frequency of a small portion of the pulsed 1.06-µm output from a Nd:YAG laser, while the major portion of the output is tuned so that the laser wavelength is spectrally located on the stee¥edge of the filter. Because of the stee¥edge of the optical filter, small shifts in frequency caused by the Doppler shift of the backscattered light are detected as significant amplitude changes, yielding high measurement sensitivity. Using a 100-MH¥filter, for example, a wind speed of 1 m/s will produce an amplitude variation of 4%, making it easily detectable, and the differential nature of the measurement makes it insensitive to linewidth and frequency drift of the laser and filter.

    PittCon `95 draws crowds to view novel instrumentation

    Sign up for Laser Focus World Newsletters
    Get the latest news and updates.

    Voice Your Opinion!

    To join the conversation, and become an exclusive member of Laser Focus World, create an account today!