Image forming apparatus and its control method
US7684079B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 16, 2005 |
| Grant date | Mar 23, 2010 |
| Priority date | — |
| Expiry date | Jan 21, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N1/6072
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image forming engine has color shifting amount storage units C, M, Y, and K (black) which store actual shifting amounts relative to ideal scan directions on image carriers C, M, Y, and K in image forming units C, M, Y, and K. Color shifting correction amount arithmetic units calculate color shifting correction amounts for respective color components to base on the stored color shifting amounts. Color shifting correction units C, M, Y, and K perform color shifting correction by converting coordinates upon reading out image data from bitmap memories C, M, Y, and K on the basis of the calculated color shifting correction amounts, and then perform tone correction. Data after tone correction undergo halftone processing by halftone processors. C, M, Y, and K to suppress moire. PWM processors C, M, Y, and K generate PWM signals for scanning, and output them to exposure units C, M, Y, and K of the respective image forming units.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.