Patent · US Expired

Laser driving apparatus and image forming apparatus using the same

US6144680A · kind A · utility

5Cited by
2References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 14, 1998
Grant dateNov 7, 2000
Priority date
Expiry dateJul 14, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01S5/0683
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A laser driving apparatus for driving a plurality of laser beam sources includes a plurality of laser beam sources, a photodetector for detecting amounts of laser beams emitted from the plurality of laser beam sources, a plurality of current sources for driving the plurality of laser beam sources, a plurality of switches respectively interposed between the plurality of laser beam sources and the plurality of current sources, a plurality of controllers for controlling light amounts of the plurality of laser beam sources by comparing the light amounts detected by the photodetector with a reference value and controlling current amounts of the plurality of current sources in accordance with the comparison values, a plurality of sample/hold circuits respectively interposed between the photodetector and the plurality of controllers, and timing adjustment device for outputting a plurality of timing signals of a first type for controlling the plurality of switches and a plurality of timing signals of a second type for controlling the plurality of sample/hold circuits. The timing adjustment device outputs the plurality of timing signals of the first type for time-divisionally turning on the…

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