Light source unit capable of changing size of light beam spot and optical scanning image recording apparatus using the same
US5175642A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 21, 1990 |
| Grant date | Dec 29, 1992 |
| Priority date | — |
| Expiry date | Dec 21, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/13727
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A light source unit comprises a laser unit for emitting a laser beam; a deflection element for deflecting the laser beam emitted from the laser unit and for outputting a deflected laser beam, a deflection angle of the deflected laser beam being controlled by a control signal supplied from an external controller to the deflection element; and a shading member for partly or entirely shading the deflected laser beam output from the deflection element, a spot size of a laser beam passing through the shading member being changed in accordance with the deflection angle of the deflected laser beam. The light source unit outputs the laser beam passing through the shading element. An optical scanning image recording apparatus using the above light source unit comprises the light source unit described above, a recording medium on which an image is formed by an optical scanning, and an optical system which moves the light beam output from the light source unit so that the light beam moved by the optical system scans a surface of the recording medium.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.