Method and apparatus for compensating for image misalignment due to variations in laser power in a bi-directional raster imaging system
US7187400B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 1, 2004 |
| Grant date | Mar 6, 2007 |
| Priority date | — |
| Expiry date | Sep 1, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/04794
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A bi-directional electrophotographic raster imaging system that sweeps a modulated light beam across an imaging region of a photosensitive surface to create both forward-going and reverse-going scanlines of dot data on the imaging region, and which compensates for image misalignment that may be caused by varying the power used to drive a laser light source that generates the modulated light beam. An SOS photosensor detects the beginning of each scanline in both forward and reverse directions, outputting an SOS signal used to create both forward and reverse margins. When the laser power is varied, compensating data is used to correct the forward and reverse margins to keep them aligned (straight), even though the beginning of the scanline locations for both forward and reverse scans are affected in opposite directions by an increase or decrease in laser power.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.