Image forming apparatus having test patterns for correcting color discrepancy
US5854958A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 1, 1996 |
| Grant date | Dec 29, 1998 |
| Priority date | — |
| Expiry date | Apr 1, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G2215/0119
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An image forming apparatus includes image forming units to transfer images onto an image receiving medium that is moved in a specified direction together with a conveyor belt which conveys the image receiving medium. The image forming units of the apparatus form test patterns on the conveyor belt or the image receiving medium. The test patterns include a leading edge and a trailing edge along the specified direction defining a distance therebetween, the distance varying continuously. The apparatus further includes a first detector for detecting the timing of the leading edge and the trailing edge of a test pattern crossing the first detector downstream of the image forming units, a second detector for detecting a shift of an image formed by the image forming units from a proper position based on the difference in the detected timings from the leading edge to the trailing edge of the test pattern detected by the first detector, and a correction unit for correcting a shift of an image formed by the image forming units based on the shifted position of the image detected by the second detector.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.