Patent · US Expired

Light source device for laser beam printer

US6711198B1 · kind B1 · utility

1Cited by
9References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 14, 2000
Grant dateMar 23, 2004
Priority date
Expiry dateApr 14, 2020

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01S5/2219
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A light source device for a laser beam printer in which a semiconductor laser is driven with a pulse current having a minimum pulse width at the ON time on the order of milliseconds or less is provided, wherein the semiconductor laser is formed so that either the rate of change at the rise portion of the pulse current becomes ±8% or less or the semiconductor laser is excited in a multiple mode in the vicinity of the threshold value of the oscillation, and the semiconductor laser oscillates in a single mode at a current separated from the threshold value, by adjusting of at least one of the width w of a stripe groove (7a) of the current block layer, the composition of clad layers (5), the distance d between the current block layer (7) and the active layer (4), the composition of the current block layer (7) and the formation of a light absorption layer into the current block layer (7). As a consequence, in the case where the light source device for the laser beam printer is driven with a short drive pulse on the order of several hundred micro seconds, the light source device becomes such that a transient phenomenon is not generated at the time of the rise of the pulse and a st…

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