Double beam scan type optical apparatus
US5140157A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 13, 1991 |
| Grant date | Aug 18, 1992 |
| Priority date | — |
| Expiry date | Mar 13, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N2201/04794
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A double beam scan type optical apparatus for use in a laser printer or the like. Such apparatus comprises two light sources and a lens system which provide scanning means for scanning a surface with parallel output light beams of the two light sources and beam distance controlling means for controlling the distance between the light beams. The reliability of the invention is improved by monitoring the intensity of the beams. Beam intensity checking means provide signals to verify that the intensity of each beam is maintained equal thus assuring that no abnormal conditions exist with the light sources or the lens system of the apparatus.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.