METHOD AND CIRCUITRY FOR BALANCING A DIFFERENTIAL TYPE FOCAL PLANE ARRAY OF BOLOMETER BASED INFRA-RED DETECTORS

摘要

The present invention relates to a bolometer type focal plane array system with circuitry for adjusting its differential measuring pixel detectors during reading, which comprises: (a) an array of i x j pixel detectors of the bolometer type for sensing scenery radiation, wherein each of said detectors provides a differential measurement of the scenery radiation, and comprises at least one resistor which is sensitive to IR radiation coming from the scenery, and at least one detector reference resistor which is masked from the scenery; (b) j column current sources (100) that comprises at least one source reference resistor (Rb) having a same TCR as of said at least one detector reference resistor, and which is thermally shorted to said substrate, wherein said current source provides to a selected detector a corresponding compensation current (Jc) which is inversely proportional to said at least one source reference resistor; (c) row selector for sequentially selecting a row n within said FPA, while connecting respectively each column current source to a corresponding pixel detector within the selected row thereby to provide a compensation current by each of said current sources to the corresponding detector; and (d) reading circuitry for reading indication for the scenery radiation as sensed by each of the i x j detectors of the array.