Research On Electronic Multiplication CCD Imaging Performance Test System

Objective evaluation of the imaging quality to the photoelectric system has always been a problem concerned,especially for the ordinary CCD cameras and some of the low light level imaging devices,it's corresponding evaluation method of the performance play a key role in the research and development of production.In the low light level imaging devices,as a result of EMCCD in performance with miniaturization,solid-state device and not easy to damage,the photoelectric conversion efficiency is high,and the advantage of passive imaging make it difficult to be found.These advantages make EMCCD application in the night fighting,reconnaissance,command and precision-guided,and other areas of the military applications play a huge role.Based on the modulation transfer function(MTF)to evaluate the quality of optical imaging that EMCCD camera as a whole,optical modulation transfer function of EMCCD is not only put forward technical requirements to the designer of the CCD camera,but provides an important parameter to the user.Therefore,this paper respectively for normal CCD camera and optical modulation transfer function of EMCCD camera and their measurement method in the following aspects are studied:In this paper,aiming at the characteristics of EMCCD,we do some theoretical research in slant knife edge method for measuring the modulation transfer function of discrete sampling device.After established the performance test method of EMCCD,we construct a suitable imaging performance parameter test of hardware and software system for EMCCD.Software simulation experiments are carried out in this test system,using the normal distribution simulation system point spread function(PSF)is carried out to verify the software algorithm,and then compare the known corresponding real MTF with the measured MTF of this software methods,our software algorithm of test system is verified that it can accurate reflection of the MTF values of test pattern under the condition of noise.We has done the actual verification contrast experiment to this test system of MTF,by comparing the same EMCCD camera in this test system and test system of CI company test results,the MTF measurement error within 2%,shows that this test system can meet the test of EMCCD imaging performance parameters,the test result reflect real value of MTF to the EMCCD camera,and our system has high reliability.The effect of the EMCCD multiplication gain on MTF measurements was tested using this test system.It was found that the charge multiplication process slightly reduces the resolving power of the EMCCD in the linear range of the EMCCD operation,we also see that the effect of charge doubling on the modulation transfer function of EMCCD is relatively small and within reasonable limits.Using this system,the influence of the incline angle on the MTF of EMCCD camera and PointGrey camera is studied.It is shown that the incline angle of the control blade is about 10 degrees,which can accurately represent the true MTF value of the camera.The effect of different spectral bands on the MTF measurement results of PointGrey camera is studied.It is shown that the imaging performance of the EMCCD camera is better than that of the single band imaging.The imaging performance of the single wavelength band is better than the shorter one Band imaging performance.In order to achieve the high efficiency of EMCCD imaging performance test,the whole calculation process more automated testing,this system adopts Labview software implementation process and the test results show that the algorithm process,the whole measurement process is more convenient and reliable.