MOVABLE MEDIA TRAY WITH POSITION REFERENCE MARKS

摘要

A printing system includes a movable tray for holding recording media. The movable tray includes spaced-apart reference marks for determining distance traveled by the tray. A reference-mark optical detector is positioned to provide a field of view through which the reference marks pass. An identifying-mark optical detector provides a field of view through which media-type identifying marks on a piece of recording medium pass. A signal processor provides an output relative to: a) amount of reference marks passing through the field of view of the reference-mark optical detector, and b) signal variation in a signal provided by the identifying-mark optical detector. A look-up table includes media identification signal patterns that are correlated to corresponding media types. Finally, a comparator compares the output of the signal processor to the media identification signal patterns in the look-up table in order to identify type of recording medium.