Abe, Also coming back to our phone conversation - there are no perfect high resolution global shutter sensor that I know of. The high resolution global shutter CCDs suffer from limited shutter ratio so some light gets into the CCD registers during readout and the image snapshot is combined with the vertically integrated signal (each pixel charge gets a little of the photoelectrons while travelling to the output shift registers. With CMOS sensors it might be better, but there are still problems related to the use of the analog memory.
The advantage of the current ERS sensors is that there is no analog memory involved in the readout process and so there are no problems with undesired light getting to the pixels in the wrong time. The only real solution I can see to the rolling effect should would be to combine memory (i.e. SDRAM) on the same chip with the sensor with wide parallel input from the sensor part, each line digitized and stored in the memory in parallel (should be easy when they are on the same chip). Until high performance sensors with such technology become available, I would rather try to use the ERS sensors perfected by the huge cellphone camera market and try to deal with undesired effects by other means. With the ERS sensor each line is exposed at different, but precisely known time. I was thinking of using the additional sensor (attached to the 10359 multiplexor board with the FPGA) to run a smaller rectangular area (i.e. 16-64 pixels high by full width - it will be 500-2000fps) and using the opposite square areas (sensor ROI has to be a single rectangle) for the "optical mouse" correlation algorithm running in the FPGA - that could provide additional information to find out orientation of the camera with high temporal precision. This orientation information can be applied to the full resolution ERS image, and used to compensate the distortions in many cases. Andrey
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