A circuit for a pixel site in an imaging array includes a light-detecting element to convert incident light to a photocurrent and a reset transistor, operatively connected to the light-detecting element, to reset a voltage associated with the light-detecting element. The reset transistor hard resets...http://www.google.de/patents/US7489355?utm_source=gb-gplus-sharePatent US7489355 - CMOS active pixel with hard and soft reset
