Patent ID: 7250958

Claim:
A method of printing a thermal medium by aligning image, the method comprising: (a) feeding a thermal medium having a first surface and a second surface so that a print starting position of the medium is past a predetermined distance from heating elements of a thermal printhead; (b) printing a first test pattern on the first surface when a front edge of the medium is detected by an edge detection sensor while feeding the medium; (c) measuring a first distance between the front edge and the first test pattern by detecting the first test pattern using the edge detection sensor; (d) rotating the thermal printhead to face the second surface; (e) feeding the thermal medium so that the print starting position of the medium is past a predetermined distance from the heating elements of the thermal printhead; (f) printing a predetermined second test pattern on the second surface when the front edge of the medium is detected by the edge detection sensor; and (g) measuring a second distance between the front edge and the second test pattern by detecting the second test pattern.