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:
Jan. 13, 1981
Filed:
Nov. 05, 1979
Thomas M Holladay, Webster, NY (US);
Xerox Corporation, Stamford, CT (US);
Abstract
An electrical screening system for binary displays or binary graphic recording systems is disclosed which suppresses false contours. The suppression is achieved by increasing the number of gray levels that a given m.times.n matrix of pixels can represent. Each pixel can only represent one of two gray levels in a binary display or graphic system. A conventional m.times.n halftone cell is able to reproduce m.times.n+1 gray levels. The extra gray levels above the m.times.n+1 quantity are achieved for a given m.times.n halftone cell by dynamically changing the values of the m.times.n screen signals associated with a halftone cell. The amount of the change is limited to a value between zero and D inclusive where D is the difference between two adjacent screen signal values.