Image forming apparatus and control method thereof having main scan length correcting feature
US7382390B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 14, 2006 |
| Grant date | Jun 3, 2008 |
| Priority date | — |
| Expiry date | Sep 20, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G15/0435
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
To detect differences in the main-scanning length of each beam on a photosensitive member, patterns for correction are formed on the photosensitive member using only beams (L1, LN) at both ends among a plurality of beams aligned in a sub-scanning direction. The patterns are transferred onto an intermediate transfer belt and detected with photosensors, a difference ΔLN of scanning length between a 1-st line and a N-th line is calculated, and a difference ΔLi of scanning length of a i-th line is calculated by ΔLi=ΔLN×(i/N−1) so as to proportionally distribute ΔLN to the i-th line. The scanning lengths of lines are respectively corrected to be equal each other using the obtained differences ΔLi of scanning length. Thus, an image forming apparatus and a control method that reduce a decline in image quality, even when scanning incident angles of laser beams onto a photosensitive member differ for each of beams on forming images by scanning a multiple lines with a multiple beams, can be provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.