Design Of Aerosol Scattering Coefficient Detection System Based On LabVIEW

In recent years, with the development of science and technology and the improvement of people's living standard in China, the visibility of the measurement is attracting more and more attention. According to the Koschmieder law, visibility is only related to the atmospheric extinction coefficient, while the atmospheric extinction coefficient is considered to be equal to the atmospheric aerosol scattering coefficient in the common visibility range of less than 100 km. So it has great practical significance for the measurement of atmospheric aerosol scattering coefficient.In the actual measurement, because of the instability of the semiconductor laser,the new measurement system is proposed in this paper. The system uses a dual light intensity detection method, the incident light is divided into two beams by beam splitter, a beam of light passes through the atmospheric aerosol, and the other beam passes through the ordinary atmosphere. At the same time, the intensity of scattered light passing through the atmospheric aerosol and the outgoing light intensity through the ordinary atmosphere are detected. Finally, the angular scattering coefficient can be calculated.This system mainly uses the single-chip and LabVIEW to carry on the processing to the signal. First, the use of single-chip acquisition of two analog voltage signals, and AD conversion, and then the signal through the serial port to the host computer for processing. And use LabVIEW to collect real-time data collection,and has a storage and playback function.The aerosols of different concentrations are tested, and the analysis shows that the linearity is good, and the correlation coefficient greater than 99%. The atmospheric aerosol measurement system has the advantages of simple operation,intuitive interface and low cost. It has a certain application value for visibility detection, especially suitable for the detection of visibility in water.