Scanning optical system
US4955682A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 28, 1989 |
| Grant date | Sep 11, 1990 |
| Priority date | — |
| Expiry date | Jul 28, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B3/02
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A scanning optical system for use in a light scanner including a light deflector for deflecting a light beam to scan a surface is disposed between the light deflector and the scanned surface. The scanning optical system focuses the defelcted light beam onto the scanned surface and keeps the scanned surface and a light beam deflecting point in substantially conjugate relationship in an auxiliary scanning direction for thereby correcting facet errors of the light deflector. The scanning optical system has a saddle-shaped convex toroidal surface having a radius of curvature in a cross section along the auxiliary scanning direction, the radius of curvature being progressively greater in a direction away from the optical axis of the scanning optical system. The scanning optical system satisfies the following condition: EQU d/f.sub.M >0.6 where f.sub.M is the focal length of the scanning optical system in a main scanning plane and d is the distance on the optical axis between the saddle-shaped toroidal surface and the scanned surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.