Development Of High Precision Scattering Visibility Meter

Atmospheric visibility is an important indicator reflecting the transparency of the atmosphere.It plays an important role in meteorological prediction,traffic safety and other fields.It is also closely related to aviation,navigation and high-speed transportation.It has developed a high-precision visibility meter with high performance.Practical value.In this paper,a high-precision scattering visibility measuring instrument is designed.The experimental data is analyzed by using the British VPF-730 Visibility Measurer as the comparison standard.Firstly,the principle of visibility measurement is analyzed.The theory of scattering and the theory of visibility measurement are summarized.The specific implementation scheme of system software and hardware design is introduced.The system hardware part is composed of an infrared transmitting module,an infrared receiving module,a sensor processing module,a main control module,a power module and a communication module.The infrared transmitting module emits the modulated infrared pulse signal,and the infrared pulse signal propagates in the air to generate a weak scattering signal,which is then focused by the convex lens to the PIN photodiode,and the infrared receiving module converts the received optical signal into a voltage signal and The signal is transmitted to the sensor processing module,and the sensor processing module amplifies and filters the received signal and transmits it to the main control module through the A/D conversion circuit,and the communication module wirelessly transmits the processed data to the upper computer display.Finally,the factors causing the visibility measurement error are analyzed,and the error is compensated.The system test is completed.The analysis of the measurement data shows that the performance of the visibility measurement instrument designed by the system meets the design requirements.