Patent · US Expired

Color halftone screen utilizing preselected halftone dots placed at preselected distance and screen angles from center halftone dots

US5202772A · kind A · utility

13Cited by
0References
34Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 28, 1991
Grant dateApr 13, 1993
Priority date
Expiry dateFeb 28, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/52
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A plurality of halftone screen density data structures utilizing halftone dot patterns which arrays the halftone dots at preselected screen angles and at a preselected distance to create a screened halftone separation. By arraying the halftone dots at preselected screen angles, the human eye is confused into perceiving continuous patterns and is less likely to perceive any Moire pattern than when using conventional methods. The data structures are created by arranging for every halftone dot in at least one halftone dot pattern of the data structures to be surrounded by a plurality of dots having their dot centers at preselected screen angles and at a preselected distance from the dot center of the center halftone dot. The halftone dots are superimposed over a plurality of bits arranged as a bit map which is representative of a pixel format utilized to produce screens wherein each bit in the bit map is assigned a value in a predetermined fashion. The values are utilized when binary representations of the density of an image for a sampled area are transformed to pixel format. Through this process, the halftone screen density data structures are utilized to transform binary representa…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.