Patent ID: 6919912
Filing Date: 2005-07-19
Classification: B41J

Abstract:
1. A method of registering the position of a ribbon by moving the ribbon with a constant angular velocity and detecting the amount of the ribbon used in a photo printer, the ribbon comprising a plurality of separation regions, a plurality of dye regions each having a plurality of dye frames, and a plurality of separation frames for dividing the dye frames; the printer comprising: a print head for transferring dye on the ribbon onto a media; a ribbon-driving device for moving the ribbon in a predetermined direction with a constant angular velocity and for accommodating the ribbon; and a photo sensor, set besides the ribbon, for generating a corresponding sensing signal; wherein the sensing signal has a first status and a second status; the method comprising: detecting a length of time of the first status when the sensing signal changes its status from the second status to the first status; determining an amount of ribbon used based on the length of time of the first status, if the length of time of the first status is shorter than a threshold, the first dye frame of the dye region is registered; determining a required moving time for the ribbon to register a start position of a subsequent dye frame of the dye region based on the length of time of the first status used to register the first dye frame of a dye region, a total length of the printed part of the dye frame, and a length from non-printed part of the dye frame to the subsequent dye frame, while one of the dye frames of the dye region is finished printing.