Abstract—CMOS image sensors are being used for more and more remote sensing camera systems because the system with CMOS can be compact and requires less power. Drawbacks of the CMOS from the point of performance are being improved nowadays. TDI CMOS image sensors are being utilized for high resolution earth observation camera systems. Intrinsic weak point of the TDI CMOS, compared to the TDI CCD, is the motion blur but lots of ways are being introduced to overcome it. As the motion blur is not critical in the TDI CCD camera thanks to the multi-phased clocking scheme, some TDI CMOS samples the signal more than once to mimic TDI CCD. One active area (photo diode) can be divided into two or more sections for better synchronization. Physical gap of the mask can be placed between pixels to mitigate the blur in the scanning direction. In this case, the motion blur can be minimized effectively, but the amount of the signal that can be collected will be reduced. Motion blur compensation is being achieved with the sacrifice of another design parameters. In this paper, alternative way of utilizing TDI CMOS camera system is introduced. Thanks to the TDI function, SNR performance is less challenging compared to the MTF that is degraded by the motion blur. Therefore, the capability of the proximity electronics adjusting the integration time make it possible to reduce the motion blur with the expense of abundant signal.Instead of physical masking between pixels, if the integration time is reduced from the line time, the resultant effects are the same but, the system can also be operated with full integration time. That means it can be selectable. Depending on the characteristics of the target, SNR prioritized image or MTF prioritized image can be selectively obtained.
 

Index Terms—CMOS, TDI, CCD, multi-phased clocking, motion blur, synchronization, integration time, signal to noise ratio, MTF

Cite: Haeng-Pal Heo and Sung-Woong Ra, "Reducing Motion Blur by Adjusting Integration Time for Scanning Camera with TDI CMOS," International Journal of Signal Processing Systems, Vol. 3, No. 2, pp. 172-176, December 2015. doi: 10.12720/ijsps.3.2.172-176