1. Identification means for a sensor array of photoelectric devices comprising: read-out means to read out accumulated charge from at least a portion of the sensor array to form an image; feature extraction means to determine, from the image, features of the sensor array comprising at least one of locations of atypical pixels and relative gray levels corresponding to the atypical pixels, in the at least a portion of the sensor array; signature generation means to generate a storable signature of the sensor array from the features of the sensor array; storage means for storing the storable signature; and comparison means to compare the stored signature with a subsequently generated signature for subsequent identification of the sensor array.