Patent · US Expired

Fast scan spot correction in a polygon ROS using PWM

US5489936A · kind A · utility

10Cited by
10References
28Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 3, 1992
Grant dateFeb 6, 1996
Priority date
Expiry dateNov 3, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N3/26
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The raster scanning system of the present invention includes a beam generator which generates a beam of radiant energy in response to a drive signal. The drive signal comprising a series of pulses. The raster scanning system further includes a polygon having an overfilled facet design in which a plurality of facets are at least partially positioned in the optical path of the beam of radiant energy regardless of the rotational position of the polygon. The polygon being adapted to scan a spot across a beam receiving surface. Additionally the raster scanning system includes spot size correcting means for maintaining a constant spot size of the scanned spot by modulating the pulse width of the drive signal provided to the beam generator.

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