Patent · US Expired

Optical Scanner

US5581392A · kind A · utility

41Cited by
3References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 27, 1994
Grant dateDec 3, 1996
Priority date
Expiry dateSep 27, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B26/124
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A scanning image forming optical system has a conjugate lateral magnification smaller than one with respect to a cross scan-corresponding direction. The optical scanner has an opening member arranged between a light source device and a deflecting-reflecting face of an optical deflector. The opening member interrupts a peripheral portion of a laser beam while the laser beam passes through an opening portion. A position of the opening member is determined such that .DELTA./L.gtoreq.0.32. Where L is a distance between a deflected light beam deflected by the optical deflector and an image formed, and .DELTA. is a distance between the image forming point and a conjugate image of the opening member. With this arrangement, it is possible to effectively reduce an influence of diffraction caused by the opening member, such as an aperture, and reduce a change in diameter of a light spot with respect to a defocusing amount.

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