Patent ID: 8126199

Claim:
A method of monitoring jets of a color imaging device, the jets respectively outputting inks of different colors, the imaging device including a monochromatic sensor that senses images output by the imaging device, the method comprising: generating a correspondence map between an output color space of the jets and an output gray scale space of the monochromatic sensor; measuring actual gray scale values of an image output by the imaging device at multiple locations, the image generated from actual image data; calculating predicted gray scale values of the monochromatic sensor for each of the multiple locations, the predicted gray scale values for each of the multiple locations including predicted gray scale values for multiple different possible operating configurations of the jets, wherein each jet can have an operating state of (i) properly operating or (ii) faulty, the different operating configurations comprising different combinations of properly operating and faulty jets for a predetermined group of the jets, each jet of the predetermined group outputting a different one of the different colors; and determining whether the jets are (i) operating properly or (ii) faulty, by comparing the measured actual gray scale values of the multiple locations with the corresponding predicted gray scale values for each of the multiple locations.