Patent ID: 6486464
Filing Date: 2002-11-26
Classification: B65H,G07D

Abstract:
A method for distinguishing a single sheet from a multiple sheet comprised of a plurality of overlapping sheets, comprising the steps of:(a) illuminating a first face of a sheet with a first radiation source positioned on a first side of the sheet; (b) sensing with a detector on a first side of the sheet, a first level of radiation from the first radiation source reflected from the first face of the sheet; (c) sensing with a detector positioned on a second side of the sheet, a second level of radiation from the first radiation source transmitted through the sheet; (d) illuminating a second face of the sheet with a second radiation source positioned on a second side of the sheet; (e) sensing with a detector on the second side of the sheet, a third level of radiation from the second radiation source reflected from the second face of the sheet; (f) generating at least one value responsive to the first level, the second level and the third level; (g) comparing the at least one value to at least one threshold, wherein a relationship of the at least one value to the at least one threshold is indicative of whether the sheet is a single sheet or a multiple sheet.