Patent ID: 6853402

Claim:
A photosensitive apparatus, comprising: a first video line, having associated therewith a first set of active photosensors, each active photosensor outputting a signal representative of light intensity thereon onto the first video line; a first correction capacitor associated with the first video line, the correction capacitor adapted to retain a correction charge thereon to influence signals from the active photosensors on the first video line; at least one dark photosensor, the dark photosensor being adapted to receive no light thereon, outputting a reference signal onto the first video line; a second video line, having associated therewith a second set of active photosensors, each active photosensor outputting a signal representative of light intensity thereon onto the second video line; a second correction capacitor associated with the second video line, the correction capacitor adapted to retain a correction charge thereon to influence signals from the active photosensors on the second video line; a multiplexing node, accepting signals from the first video line and the second video line; final correction means for performing an offset correction operation on signals downstream of the multiplexing node, the final correction means including a main correction capacitor associated with the multiplexing node, the main correction capacitor retaining a correction charge thereon to influence the voltage signals from the active photosensors from the first video line and the second video line; and means for determining the correction charge on the main correction capacitor, said determining means including means for sampling a plurality of voltage signals from the dark photosensor over time and deriving the correction charge based on a plurality of sampled voltage signals from the dark photosensor.