公开(公告)号：EP0703086A3

公开(公告)日：1998-06-03

申请号：EP95306785

申请日：1995-09-26

申请人： XEROX CORP

发明人： DONAHUE FREDERICK A

IPC分类号： B41J2/01 ,  B41J2/205 ,  B41J2/485 ,  G06K15/10

CPC分类号： G06K15/107 ,  B41J2/205 ,  G06K2215/0074

摘要： A method and apparatus for checkerboard printing by a liquid ink printing apparatus, such as a thermal ink jet printer, includes circuitry 56,58 for reducing video data rate in checkerboard printing by controlling the odd and even vertical print strokes of a reciprocating printhead mounted to a scanning carriage. The amount of bitmapped image data, also known as video data, is reduced by one half or more and prior to being sent to the printhead for printing checkerboard patterns. Reduction of the bitmapped image data is accomplished by a data packer circuit 56 which selects certain bits of the bitmapped image data for printing by the printhead in a checkerboard pattern. At the printhead, the bitmapped image is reconstructed by a data unpacker circuit 58 to cause selective ejection of ink from the appropriate nozzles of the printhead. Two or more passes information are printed to complete printing of the bitmapped image data.