A lidar system capable of remotely identifying calibrated absolute aerosol
backscatter coefficients of atmospheric aerosol particles by transmitting
a beam of light and spectrally separating the intensity of Rayleigh and
Mie backscattering is disclosed. The transmitter features high pulse
energy to generate sufficient Rayleigh backscattering, enabling
atmospheric scanning in a timely manner. The transmitter employs a seeded
Nd:YAG laser and a seeded stimulated Raman scattering wavelength shifter
to achieve narrow bandwidth, eye-safe laser pulses. The receiver employs
a telescope, collimating lens, beam splitter, molecular absorption
filter, focusing lenses, and avalanche photodiodes. Mie backscattering is
blocked by the molecular absorption filter to provide a Rayleigh signal,
which is used with knowledge of atmospheric density to calibrate the Mie
signal. The system is intended for atmospheric research and aerosol
monitoring applications where calibrated Mie scattering intensity is
necessary to measure the optical depths of aerosol structures such as
plumes, clouds, and layers.