Image forming apparatus, tone correction method using tone patches and alignment markers, and computer-readable recording medium recorded with a tone correction program using tone patches and alignment markers
US8112007B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 5, 2008 |
| Grant date | Feb 7, 2012 |
| Priority date | — |
| Expiry date | Jun 1, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G2215/0161
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention aims to provide an image forming apparatus and the like that perform a highly-accurate tone correction in a relatively short time and includes the following: a pattern former, with use of each image forming unit, on a sheet, forming tone patches in the main or sub scanning direction (41k,c,y,m) and aligning markers, which indicate positions of the tone patches, in the same direction as the tone patches (42k,c,y,m); a pattern reader reading the sheet with the tone patches and markers formed thereon; a coordinate determiner determining coordinates of the tone patches in the direction of the aligned tone patches based on the read markers (42k,c,y,m); a density determiner determining densities of the tone patches (41k,c,y,m) read based on the determined coordinates; and an updating part updating the tone correction table based on relationships between the determined densities and tone levels.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.