Patent ID: 8470733
Filing Date: 2013-06-25
Classification: B41J,B41M,G09F

Abstract:
1. A system for use in a color direct thermal printer comprising: a laterally striped direct thermal media comprising a repeating alternating pattern of at least 2 sets of stripes wherein each stripe set contains a thermochromic leuco dye producing one color when thermally imaged and each of the other stripe sets contain a thermochromic leuco dye producing a unique and different color when thermally imaged, and wherein one stripe set also contains a fluorophore and is fluorescent under excitation light of a defined wavelength range; an optical registration system configured to correspond with the optical properties of the fluorophore and comprising a confocal excitation light source configured to cause the fluorophore carrying stripe to fluoresce with an anamorphic optical return path to filter and focus the emitted fluorescence light pattern by the fluorescent stripe as an image on an a sensor; and an image processing unit configured to determine the position of each fluorescent stripe on the array sensor and configured to output a signal when a fluorescent stripe is detected at a predetermined position on the array sensor, where a flood coat of a black image forming leuco dye is uniformly flood coated on the direct thermal media prior to printing the color-forming stripe sets and the activation temperature of the black image forming leuco dye is sufficiently high that little or no activation of the black image forming leuco dye underlayer occurs when the printed stripes are imaged at a static temperature to 90% of their saturated optical density.