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:
Jun. 12, 2001
Filed:
Jan. 25, 1999
Steven H Walker, Camas, WA (US);
Kerry Lundsten, Vancouver, WA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A method and apparatus for optical determination of turn-on energy and operational printhead energy for ink-jet printing includes a computerized method for using reflectance readings from a test pattern generated by a printhead under test. The test pattern includes regions (|1|−|N|) generated by applying to the printhead ink drop generators firing pulses having a pulse energy substantially equal to a predetermined reference pulse energy at a predetermined pulse frequency starting with a pulse energy substantially equal to the predetermined reference energy and incrementally changing the pulse energy of the firing pulses such that firing pulses of increasing or decreasing pulse energies are sequentially applied to the drop generators. Using the reflectance data, determining a printhead operational firing energy pulse value that is a predetermined percentage of a turn-on energy defined as a value greater than an energy pulse value where said heaters cease to fire ink, wherein said printhead operational firing energy pulse value is provided to a printhead controller for printing operations subsequent thereto. The process can be automatically implemented in order to perform subsequent printing operation with a printhead operating energy that provides a desired print quality while avoiding premature failure of printhead heater resistors.