The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 01, 1990
Filed:
Jan. 31, 1989
Keith E Cobbs, San Diego, CA (US);
Robert D Haselby, San Diego, CA (US);
William S Osborne, San Diego, CA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
Apparatus for determining inter-pen offsets in a multiple pen ink jet printer including a drop detector for measuring flight time of ink drops, an aperture plate disposed in the print media plane, and a carriage position sensor for determining carriage position when ink drop flight time exceeds a predetermined value, which indicates that an ink jet is at the edge of the aperture plate. The sensed carriage positions for the respective pens provides information indicative of inter-pen offset in the scan axis direction. In a further embodiment of the invention, the aperture plate can have a stair-shaped boundary to facilitate the calibration of a plurality of nozzles in one scan. For determination of inter-pen offset in the media scan direction, the aperture includes a comb-like boundary that is utilized to produce the detect/no detect pattern for a nozzle array in each of the pens, whereby the pattern for each of the pens provides information indicative of the offset between pens.