The Emccd Noise Characteristics Analysis And Testing Technology

EMCCD(Electron Multiplication CCD), a new type of low-light imaging devices, has broad application prospects in low light level imaging for its having such many advantages as small size, low noise and high sensitivity. However, in the conditions of low-light and all kinds of noise interference, signal to noise ratio of the image signal obtained by EMCCD imaging system falls with the decline in the image brightness and contrast, and the image resolution has been significantly affected. Therefore, to do research on the structure, principle and multiplier feature of EMCCD, and to test and analyses the common noise of EMCCD imaging system is very significant for improving the imaging quality of EMCCD imaging system and promoting the development of low light level imaging.In this paper, the model of EMCCD charge transfer has been established based on the research of EMCCD charge multiplication mechanism, and the effect of the charge multiplication process on improving the image quality has been analysed through the establishment and research of MTF model. The equivalent noise model of EMCCD noise has also been established to respectively discuss the production mechanism of photon shot noise, dark current noise, clock induced charge noise, readout noise and transfer noise. The theoretical limit value of F, a noise factor of EMCCD has been deduced through the analysis of binomial model and poisson distribution model.In order to verify the theoretical mode, EMCCD imaging system noise test platform has been built in this paper. The experiment first completes the test of relationship between multiplier actual gain and D/A converter gain set, then tests and analyses dark current noise, noise factor F, multiplication noise using statistical methods, and makes a comparative analysis between actual test results and the theoretical model.