The Study Of Low-noise Low-light-level Image Acquisition System

For the requirement of high precision in low light imaging, designed a low light image acquisition system. This thesis focused on precise image acq uisition technology under low light circumstance,including the system design and the useful noise damping method investigation. Analysed the best working modeo f the ultra high sensitive low light image transducer, designed the low noise dr iving circuits and high speed acquisition circuits, investigated the multi-drivingand synchronization of flash.As for the system noises,use the following methods to d amp:digital multi-correlated sampling, temperature control, electrical magnetic fiel d shield and image filters.This paper composed of six chapters:Chapter one:introduced the researching and utilizing situation in and outs tate for low light imaging technology and Electron Multiplication Charge CoupledD evicc(EMCCD), proposed the content and meaning of this research program.Chapter two:analyzed the popular high performance low light image transducer, based on the normal working requirement of DC bias and driving timing, designedt he high performance driving circuits and high speed low skewed acquisition circuits.Chapter three:proposed multi-driving and synchronization solution based o n the mastering of basic driving timing designing of EMCCD, realized thesy nchronizing of flash time without electron shutter, the gain adjusting of electron m ultiplication and the adjusting of open window mode, introduced the realizing me thod of the solution in detail.Chapter four:analyzed the all noises and their characteristics of EMCCD, proposed several useful noise damping methods.Chapter five:designed different experiments to test the designed low noisea nd low light image acquisition system. After having demonstrated the validation of th e real driving timing wave and analog output signals, observed the digital imagesun der multi-driving mode, designed experiments for analyzing noise damping methodsand their usefulness, computed the real sensitivity of the system.Chapter six:summarized contents of this paper, proposed contents forf urther research.