The invention relates to a technique removing a dark voltage noise signal occurring at the time of light shielding of a photoelectric conversion device, simplifying the system configuration such that the cost and occupying area is reduced, and suppressing variation among a plurality of buffer amplifiers....http://www.google.de/patents/US7420600?utm_source=gb-gplus-sharePatent US7420600 - Photoelectric conversion apparatus with circuitry to offset dark noise
