Abstract: The present invention discloses a color printer and its printing method for accurately printing different colors on a document. The printer comprises two roller wheels for clamping and carrying the document forward and backward, a stepping motor for driving the two roller wheels, a detector for detecting a front edge of the document, a printing head for printing the document, and a control circuit for controlling operations of the printer. The control circuit comprises a memory for recording the number of steps of the stepping motor as printing position of the document.

Abstract: The present invention relates to an ink ribbon positioning system of a color printer for identifying a position of a color ink ribbon of the color printer. The ink ribbon is windingly installed inside an ink ribbon box comprising a plurality of dye blocks. Each of the dye blocks comprises a plurality of transparent color frames, and the color frames are used for storing different color dyes. The ink ribbon positioning system comprises a light source installed at one side of the ink ribbon for emitting a color light beam through the ink ribbon, an optical sensor for detecting the light beam and generating a corresponding output voltage, and an identification device for identifying positions of a dye block of the ink ribbon and color frames inside the dye block according to output voltages generated by the optical sensor and generating corresponding position signals. The color printer further comprises a thermal print head and a control circuit.