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:
Nov. 01, 1983
Filed:
Nov. 23, 1981
Joseph P Pawletko, Endwell, NY (US);
Charles R Pigos, Endicott, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method of and apparatus for controlling gray scale in the charge sensitive media of a matrix printer by using constant amplitude write pulses. Their use is intended to overcome registration problems caused by constant movement of the charge sensitive recording media during the actual print cycle. This control method and apparatus are implemented by varying, as a function of the desired intensity of one or more pixels to be printed, the effective write time and the number of constant amplitude pulses applied to any one or more of a plurality of print electrodes over a complete write cycle. The normal printer write cycle is divided into a number of subdivisions, that number being a function of the maximum permissible allowable error that can be perceived by a human eye. Further, the write pulse waveforms used are derived so that there is not more than one write cycle subdivision difference at either termination point of any intensity pixel printed therewith.