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. 23, 1995
Filed:
May. 03, 1993
Scott W Hock, San Diego, CA (US);
David A Johnson, Bonsall, CA (US);
Niels J Nielsen, Corvallis, OR (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A method for operating a thermal ink jet printer including a printhead having ink firing heater resistors responsive to pulses provided to the printhead. A sequence of pulse bursts of respective increasing or decreasing pulse energies that span a predetermined pulse energy range is applied to the printhead, each pulse burst comprised of a plurality of pulses having a pulse energy that is associated with such pulse burst and is constant for all pulses in such burst, and each burst having a sufficient number of pulses to allow the printhead to achieve a steady state operating temperature at the pulse energy of the pulse burst. A steady state operating temperature sample is determined for each of the sequence of pulses bursts of different pulse energies to produce a set of temperature samples respectively associated with the increasing pulse energies, and a turn on pulse energy is determined from the temperature samples. The thermal ink jet printhead is then operated with a pulse energy that is greater than the turn on pulse energy and in a range that provides a desired print quality while avoiding premature failure of the heater resistors.