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:
Dec. 07, 1999
Filed:
Mar. 12, 1997
Larry Capps, San Jose, CA (US);
David Albertalli, San Jose, CA (US);
Donald R Billet, San Jose, CA (US);
Gus A Adriancen, Santa Clara, CA (US);
Raster Graphics Inc., San Jose, CA (US);
Abstract
The present invention is generally directed to providing drop volume normalization of the ink jet nozzles in an ink jet printing operation to alleviate and/or eliminate banding effects due to imprecise placement of ink drops on the printed sheet and variations in the volume of drops produced by different ink jet nozzles of the print device. Exemplary embodiments relate to a method and apparatus for controlling a print device having at least one ink jet nozzle by adjusting an offset control of a power supply used to control drop volume of the at least one ink jet nozzle. In a print device configured with piezoelectric ink jet nozzles, the output drop volume of the nozzle can be controlled within a predetermined range by adjusting the voltage supplied to the ink jet nozzle. As those skilled in the art will appreciate, this offset control of drop volume will result in a change to output ink velocity as well. Accordingly, exemplary embodiments of the present invention further compensate a firing time of the at least one ink jet nozzle as a function of the offset control to account for a change in output ink velocity of the at least one ink jet nozzle.