Design of a high frame rate driver circuit for a 22 M-pixel high-resolution large-area array CCD camera and its nonuniformity correction

摘要

When using a high-resolution full-frame area array charge-coupled device (CCD) FTF4052M as the aerial image sensor of a camera, the frame rate is generally below 1 frame/second (fps), which cannot meet the requirements of applications with high frame rates. First, the FTF4052M drive circuit is introduced. Next, an improved driver circuit of the CCD 4052M is proposed. Using the CCD to output four amplifiers simultaneously yielded a maximum frame rate of 3.4 fps. Then, the timing of the CCD driver, the front-end processing circuit, the DC bias circuit, and the interface circuit of the four outputs are designed. The improved driver circuit could meet the application requirements of various aerial cameras. In addition, the FTF4052M nonuniformity is analyzed, and a nonuniformity response detection system is established. Using this system, the FTF4052M array's non-uniformity among the four quadrants and among the pixels is tested. Based on the CCD's linear responsivity, two correction algorithms are proposed to correct the nonuniformity. Finally, using the correction, the four quadrants' standard deviations of the response sensitivity are reduced by a factor of 1 /13, and the responsive nonuniformity among all pixels is reduced by a factor of 1 /10. Through the reshooting of the identified rate board, it is found that the nonuniformity of the CCD array is markedly improved.