Print head alignment method, test pattern used in the method, and a system thereof

摘要

A method of aligning one or more print heads in a print head unit and a system thereof. A first pattern of first symbols is printed on a print medium and a second pattern of second symbols is printed with a second print head on the print medium with one or more print heads in a manner to superpose the second pattern on the first pattern and so that at least some of the first symbols obscure a corresponding one of the second symbols. At least some of the second symbols are offset from a regular pattern and the offset distances are recorded. A user can designate at least one of the second symbols that is obscured by a corresponding one of the first symbols and the offset distance corresponding to the designated second symbol is used as an offset parameter for the second print head with respect to the first print head.