摘要
To reduce the charge-coupled device(CCD)readout noise and improve the detection ability under low illumination and dim targets,a new low-noise CCD signal processing technology-CCD digital denoiseis gradually being employed in aerospace detection and other fields.In this study,the main readout noise of CCD detectors and its characteristics are analyzed.A CCD digital denoise system and an experimental platform are designed as well as established by using a PCIe data acquisition card.According to the characteristics of readout noise,some digital filters are analyzed and designed based on distributed kernel coefficient,and the optimal kernel coefficients are obtained through iteration.Then,CCD signal and filter model are established,and the optimal filter is designed to apply to the digital denoise system.Finally,according to the image data obtained from the system,the performance of the digital denoise system and digital filtering algorithm is evaluated and compared.At 500 kHz and 1 MHz CCD readout rates,the denoising performance of the optimal filter designed in the experiment is 16%-32%higher than that of the digital filter with kernel distribution coefficient,and 50%-60%higher than that of the traditional correlated double sampling technology.
作者
李文灿
Wen Yan
Wang Dong
Yao Dalei
Li Wencan;Wen Yan;Wang Dong;Yao Dalei(Xi’an Institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi’an 710119,P.R.China;University of Chinese Academy of Sciences,Beijing 100049,P.R.China;College of Automation,Northwestern Polytechnical University,Xi’an 710068,P.R.China)
基金
the National Program on Key Basic Research Project(973 Program)(No.6132570201).