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:
Feb. 27, 1996
Filed:
Jul. 30, 1993
Ronald F Burr, Wilsonville, OR (US);
David A Tence, Wilsonville, OR (US);
Hue P Le, Beaverton, OR (US);
Ronald L Adams, Newberg, OR (US);
Jon C Mutton, Portland, OR (US);
Tektronix, Inc., Wilsonville, OR (US);
Abstract
An ink jet (10) apparatus and method provides high-resolution gray scale printing by providing multiple PZT drive waveforms (100, 110, 120), each having a spectral energy distribution that excites a different modal resonance of ink in an ink jet print head orifice (14). By selecting the particular drive waveform that concentrates spectral energy at frequencies associated with a desired oscillation mode and that suppresses energy at the other oscillation modes, an ink drop (170, 180, 190) is ejected that has a diameter proportional to a center excursion size of the selected meniscus surface oscillation mode. The center excursion size of high order oscillation modes is substantially smaller than the orifice diameter, thereby causing ejection of ink drops smaller than the orifice diameter. Conventional orifice manufacturing techniques may be used because a specific orifice diameter is not required. Jetting reliability and contaminant susceptibility are, thereby, improved by eliminating the need for an unconventionally small orifice. Changing a selected PZT drive waveform amplitude changes drop ejection velocity without changing drop volume. This invention, therefore, provides for selection of ejected ink drop volumes having substantially the same ejection velocity over a wide range of ejection repetition rates.