In many articles about CMOS sensor, I usually find that the relationship between readout time and frame rate is:
(1) Readout time=1/Frame rate
But Jia, C., & Evans, B. L. (2013, December) says that the readout time is usually about 60% to 90% of the time interval between frames. It means
(2) Readout time=0.6/Frame rate to 0.9/Frame rate
Which information is correct? If (1) is correct, what is the effect of the 'reset time' of each row? Is it that the 'reset time' is too small compared to the 'read time' of each row so that the 'reset time' is ignored? If (2) is correct, what are those 10% to 40% of time for?
Answer
As far as I can tell, the sensor has a fixed readout time. When using a frame rate slightly slower than the readout time, the sensor momentarily sits idle at the end of each readout, before beginning the next one - rather than slowing down the readout, which the sensor can't do.
I don't know why they give that specific range (60% to 90%) but maybe they're talking about a very specific situation rather than a general sense. I didn't read the whole paper.
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