3.2.7 Charge Bleed-back


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3.2.7 Charge Bleed-back

 

During fast transfer of a CCD image to reach the Region of Interest (ROI) of a PFI, charge builds up in the serial shift register of the CCD. This charge must be shifted out lest it bleed back onto the CCD and corrupt the image. A commandable guard band is provided to prevent this problem. However, on a few occasions charge bleed back is apparent in PFIs taken with the aspect sensor. The result is saturated columns appearing in the image, usually in the middle where 2 ROIs have been pasted together to create a 2 exposure PFI. A good (bad) example is

 18-AUG-92  04:46:30  QT/H  NaBan/Open  Full Norm C  20   948.0  128x128
There is no way to recover data corrupted by bleed back.


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