Patent · US Expired

Multi-beam scanning apparatus

US6185026A · kind A · utility

71Cited by
3References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 3, 1999
Grant dateFeb 6, 2001
Priority date
Expiry dateAug 3, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B26/123
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A multi-beam scanning apparatus performs image scanning by emitting multiple beams from a plurality of light sources, which beams are deflected by a common deflector at equiangular velocity. The beams are then condensed by a common scanning image forming lens so as to form optical spots on a scanning surface. As a result, the plurality of lines are simultaneously scanned by the beams on the scanning surface at a substantially constant velocity. Characteristics of the light sources, such as the wavelength thereof, and other factors such as writing density and desired writing width of a writing line, are arranged to eliminate differences in a written vertical line in a sub scanning direction caused by a magnification difference, regardless of the cause of such differences. In addition, the modulation frequency of the plurality of light sources is made different from each other so that writing widths of the dots written by the plurality of light sources become the same.

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