Optical scanning apparatus capable of reducing variations in shading and improving light usage
US6229638A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 1, 1999 |
| Grant date | May 8, 2001 |
| Priority date | — |
| Expiry date | Jun 1, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S359/90
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical scanning apparatus reduces shading and variations in light intensity and significantly increases light usage during an optical scanning process using a simple construction in which a laser beam from a light source is deflected by a light deflector having a reflective surface and is focused to a spot upon a scanning surface by a scanning lens to thereby perform optical scanning. The light source is arranged to produce a laser beam which includes both P-polarized light and S-polarized light. A direction of polarization of the light source is inclined in a plane perpendicular to the optical axis with respect to both the deflecting direction (the Y-axis direction) and a direction perpendicular to the deflecting direction (Z-axis direction). The laser beam impinges upon the reflective surface as polarized light which is between P-polarized light and S-polarized light, such that shading is minimized and variations in light intensity are significantly reduced and light usage is greatly increased during the optical scanning process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.