Media-tracking system using deformed reference marks

摘要

A system is described for tracking a position of a receiver medium as it travels along a media path. A heat source provides heat to the receiver medium in a localized area sufficient to permanently deform the receiver medium to form a reference mark. A light source illuminates the receiver medium, and a sensor is used to sense light from the light source that is transmitted through the receiver medium or reflected from the receiver medium thereby providing a sensed light level signal. The sensed light level signal is analyzed to determine a position of the receiver medium by detecting a change in the sensed light level signal that is characteristic of the physical deformation associated with the reference mark.

主权项

1. A system for tracking a position of a receiver medium as it travels along a media path, comprising:
a heat source located at a first position along the media path adapted to provide heat to the receiver medium in a localized area, the receiver medium being formed from a thermally deformable material, the provided heat being sufficient to permanently deform the localized area of the receiver medium to form a reference mark characterized by a physical deformation of the localized area of the receiver medium; a light source that illuminates the receiver medium when it has traveled to a second position along the media path; a sensor adapted to sense light from the light source that is transmitted through the receiver medium or reflected from the receiver medium thereby providing a sensed light level signal; and a data processor adapted to analyze the sensed light level signal to determine a position of the receiver medium as the receiver medium passes through the second position along the media path by detecting a change in the sensed light level signal that is characteristic of the physical deformation of the localized area of the receiver medium associated with the reference mark.