Scanner having a misalignment detector
US5594556A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 21, 1994 |
| Grant date | Jan 14, 1997 |
| Priority date | — |
| Expiry date | Mar 21, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/04794
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A laser scanning device is disclosed which includes a spinner, one light spot misalignment detector and a beam misalignment corrector. The spinner scans a light beam across a scanning line. The detector is located generally at a beginning of the scanned line and measures an initial misalignment of the light spot in a cross-scanning direction. The corrector dynamically corrects, during scanning along said scanning line, the scanning misalignment of the light beam in accordance with at least the initial misalignment. The corrector includes a pre-positioner which determines an offset for the initial misalignment, a pyramidal error estimator which estimates a first portion of the misalignment due to pyramidal error and a wobble estimator which estimate a second portion of the misalignment caused by wobble. The estimations are summed together and used for correcting the misalignment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.