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. 12, 1991
Filed:
May. 04, 1990
Christopher W Thomson, Etobicoke, CA;
Delphax Systems, Randolph, MA (US);
Abstract
An electrographic printhead assembly comprises first and second sets of electrodes which define an array of crossing regions for generating packets of electric charge. An RF electrode burst actuates a first electrode to generate charge carriers while a varying extraction potential is developed. A second electrode is then activated with one or more control pulses which are synchronized with the RF burst and with selected portions of the varying extraction potential to gate charge carriers from the printhead. This deposits the desired charge level for each dot on an imaging member. The assembly forms a gray scale latent image for printing, and provides enhanced range without requiring higher frequency or longer duration RF bursts.