Beam position sensor for a light beam scanner
US5023448A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 16, 1989 |
| Grant date | Jun 11, 1991 |
| Priority date | — |
| Expiry date | Oct 16, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/04794
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A beam position sensor for a beam scanner is disclosed for use in a laser printer. The printer comprises three diode lasers each of which emits at a different wavelength. The beams from the three lasers are combined by the use of dichroic plates to form one combined beam. The combined beam is scanned onto a receiving medium by a polygon. The beam position sensor of the present invention is adapted to sense the position of the polygon in order to provide a synchronizing signal which will insure that each raster line in the printer is started at the proper position. The beam position sensor includes a diode laser and optics for projecting a beam from the laser onto the polygon. The beam is reflected back from the polygon into a photodetector which effects the start of a new raster line at the appropriate time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.