Systems and methods for compensating for streaks in images
US7095531B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 6, 2003 |
| Grant date | Aug 22, 2006 |
| Priority date | — |
| Expiry date | Sep 2, 2024 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J29/393
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Defects in an image forming system may give rise to visible streaks, or one-dimensional defects in an image that run parallel to the process direction. One known method for compensating for streaks introduces a separate tone reproduction curve for each pixel column in the process direction. A compensation pattern according to this invention has a plurality of halftone regions that are lead by, trained by, and separated by rows of fiducial marks. The fiducial marks allow the printer pixel grid and a scanning pixel grid to be correlated. The gray level in each pixel column of each gray level portion is measured and analyzed to produce a local tone reproduction curve for each pixel column and associated line width. The local tone reproduction curves are then used to compensate for the streak defect when printing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.