The design and performance of a two-dimensional photodiode visible imager with a means of reducing the reset noise below the kTC limit is discussed. This active reset scheme uses feedback with an opamp per column in order to increase the gain and therefore the noise reduction over that seen for ordinary “soft” or “flushed” reset. The scheme is compatible with a practically-sized visible imager pixel, 10 µm in this case.
01 June, 2003