Patent ID: 8356870

Claim:
A label printer comprising: a carriage that moves bi-directionally in a main scanning direction over a disc-shaped recording medium; a printer tray that is disposed movably in a sub-scanning direction with the recording medium placed thereon; an ink head that is disposed to the carriage and prints a desired object by discharging ink to a printing area on the recording medium in conjunction with movement of the carriage in the main scanning direction and movement of the printer tray in the sub-scanning direction; a detection unit that is disposed to the carriage and detects a reference position alignment mark that indicates a rotational position used as a reference for appropriately printing the object in the printing area of the recording medium; a rotating unit that rotates the recording medium; and a printing operation control unit that rotates the recording medium using the rotating unit so that the object is printed in the printing area of the recording medium, the printing operation control unit calculating the angle of rotation of the recording medium, the angle of rotation calculation being based on the detection of the reference position alignment mark by the detection unit.