A New Lidar Technology Using Frequency Comb Light Source

摘要

As the increasing demands of the environmental protection, meteorological monitoring, ecological detectionand other fields, lidars are needed to simultaneously measure a variety of atmospheric parameters (especiallysimultaneous measurement of various pollutants, such as volatile organic solvent VOCs). Multi-wavelengthRaman lidar, differential absorption lidar (DIAL) and high spectrum resolution lidar (HSRL) can be implementedthese fields. But either technique needs multiple laser sources to meet their requirements. This paper proposes anew lidar based on Frequency Comb Light Source, which can provide multiple frequency components through asingle light source for simultaneously measuring various multiple atmospheric parameters. The frequency comblaser light source is used to emit seed light of frequency ωc from the seed laser, and then after passing through thefrequency comb laser, a series of equally spaced spectral frequency components are emitted centered on ωc; thenemitted into the atmosphere, and the laser reacts with the atmosphere. The echo signal enters the receiving opticalpath through the telescope, and is sent through the beam splitter or the discriminator to detect by the detector.Based on different pollutants have different absorption cross sections, similar differential absorption lidar(DIAL),the λon and λoff can be determined. The lidar using the frequency comb light source can be easy designed into acompact structure, which is convenient to carry and maintain. It’s also a very advantageous for the lidarminiaturization and industrialization with a wide application prospect.