Patent · US Expired

Light beam scanning apparatus

US4933549A · kind A · utility

31Cited by
2References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 8, 1988
Grant dateJun 12, 1990
Priority date
Expiry dateDec 8, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N2201/04794
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A multi-beam detecting apparatus adapted to an optical system in which a recording medium is scanned by a plurality of light beams emitted from respective light sources, includes a photodetector, a light interrupting member, and a control circuit. The photodetector produces detection signals when the corresponding light beams come to a predetermined position. The light interrupting member is interposed between the light sources and the light detecting member, and has transparent portions related to the respective light beams. A controlling circuit controls ON/OFF states of the light source in accordance with the respective detection signals related to the corresponding light beams passing through the respective transparent portions in the light interrupting member.

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