Patent · US Expired

Image recording apparatus with improved SOS detection

US4888647A · kind A · utility

7Cited by
6References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 14, 1989
Grant dateDec 19, 1989
Priority date
Expiry dateMar 14, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N2201/04744
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An image recording apparatus comprises a laser light source for generating a primary beam for scanning and a secondary beam for monitoring the light amount thereof which has a photodiode for detecting the light amount of the secondary beam. The output signal of the photodiode obtained when only the secondary beam is incident on the photodiode is distinguished from the output signal of the photodiode obtained when the secondary beam and the primary beam having been reflected from a deflecting surface are incident at the same time on the photodiode in order to output a start of scan signal for every one scan line at a moment when the primary beam and the secondary beam are incident at the same time on the photodiode.

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