I know that in CMOS sensor, the exposure is perform in line by line. I can assume that the delay between the exposure of two consecutive lines is equal the readout time for one line. So the readout time for the entire frame is
Frame_readout = line_readout * number_of_line
I read in many articles in the Internet that the interval between frames is qual the frame readout time. So the frame rate is calculated as
Frame_rate = 1/frame_readout
Therefore I assume that the delay between exposure of the last line of the 1st frame and the first line of the 2nd frame is equal the readout time for one line. It means that exposure in the sensor occurs from the first line to the last line and then come back to the first line (for next frame) and so on. And the delay between the exposures of two consecutive lines are always the same, whether these two exposures belong to the same frame or not.
Is my assumption correct? If not, what does contribute more delay for the exposure of the first line of the next frame? And what is the frame rate in that case?