EMCCD Drive Circuit Design And Optimization

After years of development, CCD has been widely used in many aspects, such as industrial testing, security monitoring, astronomical observation, space detection etc. and its application scope is also extended from the original visible-light condition to the low-light environment. EMCCD (Electron Multiplication CCD) is a new type of solid-state imaging sensor. Owing to the on-chip multiplication technology, EMCCD obtains the same level of sensitivity compared with ICCD and EBCCD. Due to its high quantum efficiency and low noise, EMCCD has a broad development prospects in the field of low light level imaging.The design of driving circuit is an important part of EMCCD camera, the digital signals have large noise margin and strong anti-interference capability, so the design of analog front-end (AFE) circuit will decide the performance of the EMCCD imaging system. The thesis presents the structure and working principle of EMCCD image sensor. Main performance index of EMCCD is analyzed to provide the theoretical foundation for analog circuit design. The CCD97from E2V Technologies is chosen as the image sensor. The FPGA is adopted to generate the driver timing of CCD97. The integrated devices and discrete circuits are used for the design of analog driver circuit. By adopting a12bit analog-to-digital conversion chip with Correlation Double Sampling (CDS) function, the image data of CCD97output signal is digitized. In consideration of the power distribution system (PDS), this paper analyses the working principle of stabilized voltage supply, designs the low noise bias power supply to realize the multiplication gain adjusting of EMCCD. The thesis focus on designing and optimizing the drive circuit, analog-to-digital conversion circuit, low noise power supply and signal integrity, to design a low noise, low power consumption EMCCD camera which is suitable for low-light environment.The test results show that under the condition of low illumination, the images captured by EMCCD camera has high signal-to-noise ratio, meet the requirement of application.