US 8,262,190 B2 · Method and system for measuring and compensating for process direction artifacts in an optical imaging system in an inkjet printer

Abstract

A printer operating method enables a controller to identify process direction errors in an optical imaging system. The method includes identifying a printhead roll error for each printhead in a plurality of printheads in a printer, moving each printhead by an amount that corrects the printhead roll error for the corresponding printhead, generating a plurality of dashes on media with the plurality of printheads as the media moves past the plurality of printheads, identifying a position for each dash in the process direction from image data of the plurality of dashes on the media, identifying a displacement in the process direction for each optical detector in a linear array of optical detectors used to generated the image data of the plurality of dashes, the displacement being identified with reference to the identified positions for the dashes, and operating the printer to compensate for the identified displacements of the optical detectors.

Claims18

Dependent claims

A method for detecting and compensating for displacement of an optical imaging system from an expected position across a path for a media path in a printer comprising:

identifying a printhead roll error for each printhead in a plurality of printheads in a printer;
moving each printhead by an amount that corrects the printhead roll error for the corresponding printhead;
generating a plurality of dashes on media with the plurality of printheads as the media moves past the plurality of printheads;
identifying a position for each dash in the process direction from image data of the plurality of dashes on the media;
identifying a displacement in the process direction for each optical detector in a linear array of optical detectors used to generated the image data of the plurality of dashes, the displacement being identified with reference to the identified positions for the dashes;
and
operating the printer to compensate for the identified displacements of the optical detectors.

4 more elements

A printer comprising:

a media transport that is configured to transport media through the printer in a process direction;
a plurality of print bars, each print bar having a plurality of printheads mounted to each print bar and each printhead being configured to eject ink onto media being transported past the plurality of print bars by the media transport;
an imaging device mounted proximate to a portion of the media transport to generate image data corresponding to a cross-process portion of the media being transported through the printer in the process direction after the media has received ink ejected from the printheads;
and
a controller operatively connected to the imaging device and the plurality of printheads, the controller being configured to operate the printheads to eject ink onto media to form a first plurality of dashes as the media is being transported past the printheads on the bars, to receive image data of the first plurality of dashes on the media generated by the imaging device, to process the image data to identify a displacement distance for each optical detector in the imaging system with reference to an identified position for each dash in the image data of the first plurality of dashes, and to compensate for the identified process direction displacements in operation of the printer.

2 more elements

Dependencies are inferred from the claim text.

Method and system for measuring and compensating for process direction artifacts in an optical imaging system in an inkjet printer

Life of this patent

Method and system for measuring and compensating for process direction artifacts in an optical imaging system in an inkjet printer

Life of this patent

Abstract

Claims18