Method and apparatus for enhancing the dynamic range of a ccd sensor

摘要

An imaging system having a CCD sensor varies the intensity of an input image presented to the sensor during an integration period of the sensor to enhance the intra-scene dynamic range of the imaging system. The sensor well depth of the CCD sensor is also varied during the integration period in a manner that complements the intensity variation to achieve the dynamic range improvement. In one approach, the intensity of the input image is progressively decreased during the integration period while the sensor well depth is correspondingly increased. In another approach, an intensifier unit is gated off during the integration period to provide the intensity variation. A closed loop control method is provided for controlling the image intensity and/or the well depth based upon the content of the present image.