Patent · US Expired

Scanning and imaging lens, optical scanning device and image forming apparatus

US6448998B1 · kind B1 · utility

72Cited by
2References
31Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 29, 2000
Grant dateSep 10, 2002
Priority date
Expiry dateSep 7, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B26/125
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A scanning and imaging lens condensing a light flux deflected by a deflector onto a surface to be scanned as a beam spot, has a plurality of lenses. A shape in main scanning cross section of each of both surfaces of a lens on a side of deflector has a convex shape, and a shape in main scanning cross section of at least one surface of the lens on the side of deflector is a non-arc shape. A shape in main scanning cross section of a first surface of a lens on a side of surface to be scanned has a convex shape, and a shape in main scanning cross section of at least one surface of the lens on the side of surface to be scanned is a non-arc shape. The scanning and imaging lens has at least two special toroidal surfaces in each of which a curvature in sub-scanning cross section varies in main scanning direction.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.