US 11,402,511 B2 · Spectrally-resolved raman water lidar

Abstract

A spectrally-resolved Raman water lidar, including: a transmitter unit, a receiver unit, and a data acquisition and control unit. The transmitter unit includes a seeder, a solid Neodymium-doped Yttrium Aluminum Garnet (Nd:YAG) laser, a beam expander, and a first reflecting mirror to emit a 354.8-nm laser beam. The receiver unit includes a telescope, an iris, a collimator, a second reflecting mirror, a first bandpass filter, a beam splitter, a narrow-band interference filter, a third lens, a first detector, a second bandpass filter, a coupler and a home-made dual-grating polychromator to enable simultaneous profiling of backscattered Raman spectrum signals from water vapor, water droplets and ice crystals as well as aerosol fluorescence in the atmosphere. The data acquisition and control unit includes a computer to store the acquired data and guarantee an automatic operation of the lidar system through a time-sequence circuit.

Claims6

Dependent claims

A lidar, comprising:

a transmitter unit;
a receiver unit;
and
a data acquisition and control unit;
wherein:
the transmitter unit comprises an injection-seeded solid laser configured to emit and guide a narrow-band 354.8 nm laser beam zenithward;
the receiver unit is configured to collect signals from atmospheric backscatters, and to sample extended three-phase Raman water spectra between 393.0 nm and 424.0 nm with a 1.0-nm spectral resolution;
and the receiver unit exhibits a suppression of more than 15 orders of magnitude to an elastic signal around 354.8 nm and a suppression of more than 6 orders of magnitude respectively to O2 and N2 ro-vibrational Raman signals around 375.5 nm and 386.8 nm;
wherein the extended three-phase Raman water spectra between 393.0 nm and 424.0 nm comprise full Raman spectra of water and two Raman spectra segments of aerosol fluorescence that are free of Raman signal of water;
and
the data acquisition and control unit is configured to store acquired data.

8 more elements

Dependencies are inferred from the claim text.

Spectrally-resolved raman water lidar

Life of this patent

Spectrally-resolved raman water lidar

Life of this patent

Abstract

Claims6