| Photomultiplier Tube (PMT) is an important photoelectric detecting apparatus. It preceeds to other sensitive apparatus and has the advantage of fast response, low cost, large photocathode area and so on. It is mainly used in lidar. Since it is the important part of lidar, its performances affect the precision of measured signal. The studies of PMT used in lidar are focused on its characteristic and simulation.Many improved methods are put forward, and the precision of measured signal is improved. The photoelectric detectors of the lidars developed by our Laboratory-- Key Laboratory of Ocean Remote Sensing, Ministry of Education, Ocean University of China, are PMTs, so the study of PMT is important.The existent study of PMT, its theory and characteristic are introduced in this thesis. A PMT simulation system is developed based on Labview. The simulation system has two parts: the database of PMT and the simulation module of PMT. The database serves for simulation, so that correlative data can be picked up. The simulation of PMT includes: the simulation of emission of thermion of different kinds of photocathode; the simulation of charge spectrum of PMT by Monte Carlo method; the simulation of response of PMT in linear illumination; an example of designing circuitry; the simulation of minimum detectable energy, detectable altitude and SNR of measured signal by PMT; the simulation of Afterpulse. The thesis detailedly discusses the results of simulation above.Further more experimentations on PMT used in detecting atmosphere are carried out: the change of dark counts with temperature of CR131-1 and CR131-2 is measured; the change of dark counts with time of raising high voltage is studied; a method of measuring PHD of PMT is put forward, and the PHD of CR120 and CR105 is measured using this method;The plateau and PHD of R7400 used for detecting the atmosphere are measured, which provide the gist for the application.The studies above in this thesis are significant.
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