Miniaturized Continuous Wave Lidar Technique Based On The Scheimpflug Principle

Forty-three years since the reform and opening up,the field of science and technology in China has developed at a high speed.Strutting forward on the road of a powerful country in science and technology.While attaching importance to the development of science and technology,we should deal with the harmonious relationship between human beings and nature,and pay attention to the environmental pollution caused by human activities.Air pollution is an urgent problem which is closely related to human production and life.With the development of science and technology,the detection methods for air pollution are constantly improving.Compared with point measurement technique,lidar,as an active remote sensing technique,has great potential in detecting spatial and temporal distribution of atmospheric parameters.At present,as a mainstream technique in the field of atmospheric lidar,pulsed lidar has been well developed.This technique still has the challenges of high cost of equipment components,difficult maintenance,complex optical components and mechanical structure.The Scheimpflug lidar(SLidar)based on Scheimpflug principle has characteristics such as low cost,simple structure and easy maintenance.In order to solve the problems of large volume and poor portability of atmospheric lidar,a miniaturized continuous optical atmospheric lidar system based on Scheimpflug principle is proposed and implemented in this paper.The actual measurement performance of atmospheric aerosol,extinction coefficient,atmospheric visibility and other parameters are verified by all-weather continuous measurement.This paper first introduces the influence of atmospheric aerosols on human production and living,secondly introduces the laser propagation in the atmosphere features,including atmospheric absorption and scattering phenomenon,then discusses the principle of pulsed lidar and SLidar,optical structure and atmospheric extinction coefficient inversion algorithm,and their respective lidar equations.Then,the system structure and other information of the miniaturized lidar based on Scheimpflug principle are introduced.Finally,the performance of the miniaturized lidar system is verified by the all-weather atmospheric aerosol monitoring over Dalian City.The system uses an 808 nm laser diode as the light source A 114 mm Newtonian reflector telescope and a CMOS are the receivier.The total mass of the system is about 20kg.Through December 2019 to January 2020 between the experiment,of the atmosphere above the level in dalian(elevation is about 2°)and 45°inclined all-weather measurement,and analysis the 2 km within the measuring range of the atmosphere to the scattering intensity and atmospheric extinction coefficient,and further calculate the atmospheric visibility,and analyze the relationship between SNR and the background value.The atmospheric extinction coefficient and atmospheric visibility were compared with the PM₁₀concentration data of Qixianling Meteorological Monitoring Station in Dalian City,and a good agreement was obtained.This work provides an idea for the design of a new type of atmospheric lidar system,verifies the performance of a miniaturized lidar system based on the Scheimpflug principle,and shows its application potential in atmospheric monitoring.