Ramping dot data for single-pass monochrome printing at high speeds

Patent metadata

Field	Value
Publication number	US-2022072851-A1
Application number	US-202117468164-A
Country	US
Kind code	A1
Filing date	Sep 7, 2021
Priority date	Sep 9, 2020
Publication date	Mar 10, 2022
Grant date	—

Abstract

A method of printing an image from a printhead module having a plurality of horizontal nozzle rows. The method includes the steps of: allocating first dot data for an image line of the image to nozzles in a main row portion of a first nozzle row; allocating second dot data for the image line to nozzles in a dropped row portion of the first nozzle row; sending the first and second dot data to the printhead module and firing respective droplets. Some bits of the first dot data correspond to pixels of the image line aligned with the dropped row portion, and some bits of the second dot data correspond to pixels of the image line aligned with the main row portion.

First claim

1 . A method of printing an image from a printhead module having a plurality of horizontal nozzle rows, each nozzle row having a main row portion and a corresponding dropped row portion vertically offset from the main row portion, the method comprising the steps of:
allocating first dot data for an image line of the image to nozzles in a main row portion of a first nozzle row; allocating second dot data for the image line to nozzles in a dropped row portion of the first nozzle row; sending the first dot data to the printhead module and firing droplets, based on the first dot data, from nozzles of the main row portion; sending the second dot data to the printhead module and firing droplets, based on the second dot data, from nozzles of the corresponding dropped row portion, wherein: one or more bits of the first dot data correspond to pixels of the image line aligned with the dropped row portion; and one or more bits of the second dot data correspond to pixels of the image line aligned with the main row portion.

2 . The method of claim 1 , wherein said bits of the first dot data are allocated to nozzles of the main portion proximal the dropped row portion.

3 . The method of claim 2 , wherein said bits of the second dot data are allocated to nozzles of the dropped row portion proximal the main row portion.

4 . The method of claim 1 , wherein the first nozzle row of the dropped row portion corresponds to the first nozzle row of the main row portion.

5 . The method of claim 1 , wherein the second nozzle row of the dropped row portion does not correspond with the first nozzle row of the main row portion.

6 . The method of claim 1 , wherein the dropped nozzle portion has a plurality of columnar zones, and the bits of second dot data aligned with the main nozzle portion are ramped across the columnar zones towards the main nozzle portion.

7 . The method of claim 1 , wherein allocation of first and second dot data to nozzles of the main row portion and dropped row portion is performed in a printer controller communicating with the printhead module.

8 . The method of claim 1 , wherein the printhead module has redundant nozzle rows.

9 . The method of claim 1 , wherein the printhead module is a monochrome printhead module having all nozzle rows supplied with a same color ink.

10 . The method of claim 1 , wherein the nozzle rows of the dropped nozzle portion together are generally trapezoidal or triangular in plan view.

11 . The method of claim 1 , wherein:
third dot data for the image line is allocated to a second nozzle row of the main row portion; fourth dot data for the image line of is allocated to the corresponding the second nozzle row of the dropped row portion; one or more bits of the third dot data correspond to pixels of the image line aligned with the dropped row portion; and one or more bits of the fourth dot data correspond to pixels of the image line aligned with the main row portion.

12 . The method of claim 1 , wherein the first and second dot data correspond to even pixels of the image line, and the third and fourth dot data correspond to odd pixels of the image line or vice versa.

13 . The method of claim 1 , wherein the second dot data is sent to the printhead module subsequent to the first dot data.

14 . The method of claim 1 , wherein the dot data comprises a ‘1’ for an enabled firing nozzle and a ‘0’ for a non-enabled non-firing nozzle.

Assignees

• Memjet Technology Ltd

Inventors

• Brown Brian
• Hogan Julie
• Palliser Ronan
• Nazneen Keshu
• Le Hir Juliette
• Hardy Rodney

Classifications

• B41J2202/20

  Modules · CPC title

• B41J2/04586

  controlling heads of a type not covered by groups B41J2/04575 - B41J2/04585, or of an undefined type · CPC title

• B41J2/145 Primary

  Arrangement thereof · CPC title

• B41J2/2135 Primary

  Alignment of dots · CPC title

• B41J2/04505 Primary

  aiming at correcting alignment · CPC title