Development Of Probe Of Cloud Droplet Base On Theory Of Forward-scattering

Probe of cloud droplet is one of the most important instruments in the weather modification activities.Today our country are mainly rely on import foreign equipment，Its shortcomings were reveled in the purchase price,calibration and maintenance costs in the long-term used, especially the inherent problems.To construct a probe of cloud droplet which can be used in routine observation, the optical scheme, circuit and signal processing system were designed, successfully a domestic probe of cloud droplet base on theory of forward-scattering is developed.In this system, a single-mode685nm diode laser with single-mode fiber output coupling was used as a transmitter, the illuminating laser was abandoned by the round rubber of4mm on the45°mirror, and the depth of field of this system was controlled by a200μm pinhole placed on the focal plane of the collecting system. Standard particles with known sizes (5μm、15μm、20μm、30μm、40μm) were used to calibrate the system and the responsing curve to standard particles was obtained. In the end, Mie theory was used to study the corresponding relationship between standard particles and cloud droplet. Using this relationship, the responsing curve to standard particles was converted to the responsing curve to cloud droplets which can be used to measure the sizes of cloud droplets.According to the actual demand in our country, the existing equipment is insufficient. Improvements added in the new instrument, such as small drop edge blur problem solution and the comparison signal, are new technological improvement.