Reducing the visibility of color changes caused by color plane registration variations in halftone color printing
US8355189B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 14, 2010 |
| Grant date | Jan 15, 2013 |
| Priority date | — |
| Expiry date | Aug 11, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/52
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A set of screens is provided for use in printing respective color separations in a halftone color printing process. This set of screens comprises at least two clustered-dot screens and the frequency and angle parameter values of the screens is such that the lowest frequency moiré produced by any combination of at least two frequency components, taken from the group comprising the first and second screen harmonics, for which the sum of the harmonic orders of the frequency components in the combination is less than a predetermined value, is of a sufficiently high frequency as to be substantially unperceivable to the human visual system; other moirés are also substantially unperceivable to the human visual system. The lowest frequency moiré serves to reduce the visibility of color changes caused by color plane registration variations. A printing system and method employing the screen set are also provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.