Defective printer nozzle compensation control
AssigneeSeiko Epson Corporation
InventorYuko Yamamoto
Life of this patent
Estimating the term…
Abstract
Ink ejection problems of black ink nozzles are compensated for by forming dots by mixing cyan, magenta, and yellow inks without reducing print quality. When a nozzle that discharges black ink becomes unable to properly eject ink, cyan, magenta, and yellow inks are ejected from respective nozzles to the discharge area on the recording medium to which the defective nozzle should eject ink. The volume of cyan, magenta, and yellow ink that is ejected is set based on the amount of black ink that should be ejected by the defective nozzle.
Claims9
A control method for a printing device that has a printhead having a plurality of nozzles configured to eject black ink and a plurality of nozzles configured to eject other colors of ink onto a recording medium based on print data, and that prints by compensating for any of the plurality of nozzles for ejecting black ink that is detected to be a defective nozzle that cannot eject ink normally, the control method comprising:
- performing a defective nozzle compensation process when it is detected that the print data contains data for one of the plurality of nozzles that is to eject black ink to a discharge area is a defective black ink nozzle, the defective nozzle compensation process comprising:
- determining a size of black dot data assigned to the discharge area that is to be formed by the defective black ink nozzle, and
- determining whether dot data of at least one of the other colors is assigned to the discharge area, if it is determined that large or medium dot data is assigned to the discharge area,
- selectively ejecting ink of at least one of the other colors to the discharge area to which the defective black ink nozzle should eject black ink, the volume of ink of the at least one of the other colors to be ejected to the discharge area, when ejected, being set based on results of the determining steps, and
- when at least one of the other colors is ejected to the discharge area, discharge data for the defective black ink nozzle is deleted.
A printing device comprising:
- a printhead having a plurality of nozzles configured to eject black ink and a plurality of nozzles configured to eject other colors of ink;
- and
- a control unit that selectively causes the pluralities of nozzles to black ink and other colors of ink onto a recording medium based on print data, the control unit being further configured to:
- detect whether any of the plurality of nozzles that is to eject black ink to a discharge area is a defective black ink nozzle,
- determine a size of black dot data assigned to the discharge area that is to be formed by the defective black ink nozzle,
- determine whether dot data of at least one of the other colors is assigned to the discharge area, if it is determined that large or medium dot data is assigned to the discharge area,
- selectively eject ink of at least one of the other colors to the discharge area to which the defective black ink nozzle should eject black ink, the volume of ink of the at least one of the other colors to be ejected to the discharge area, when ejected, being set based on results of the determine operations, and
- delete discharge data for the defective black ink nozzle when at least one of the other colors is ejected to the discharge area.
Dependencies are inferred from the claim text.