Black and white reference and end-of-scan indicator for charge coupled devices

Claim 1

A charge-coupled device fro generating signals corresponding to an ambient light condition, a reference dark condition, and a reference light condition comprising in combination: a plurality of photosites, each of said photosites being responsive to ambient light for accumulating a charge having a magnitude corresponding to the intensity of the ambient light impinging thereon; means for exposing a first predetermined number of said photosites to said ambient light: means for shielding at least one dark reference photosite from ambient light whereby said at least one photosite accumulates a charge having a magnitude corresponding to said reference dark condition; means for electrically isolating said first predetermined number of photosites from said at least one dark reference photosite to thereby prevent charge accumulating in said first predetermined number of photosites from flowing into said at least one photosite; means for injecting and storing a white reference signal charge indicative of the upper limit of the linear range of sensitivity of the photosites; an output gate; means for transferring said white reference signal charge and the charges from said first plurality of photosites and from said at least one dark reference photosite to said output gate; and signal processing means for converting the charge from said dark reference photosite into a dark reference signal and the charge from said white reference charge injecting means into a white reference signal and for converting the charge from said first plurality of photosites into video signals.