Patent · US Expired

Light illumination assembly having a tapered light guide plate for an optical reading unit

US5737096A · kind A · utility

28Cited by
3References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 26, 1996
Grant dateApr 7, 1998
Priority date
Expiry dateMar 26, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G15/0435
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An optical guide device in an optical reading system incorporated in a facsimile device, copying machine, image scanner and the like includes an array of LEDs and a light guide plate. When the light guide plate is cut along the longitudinal axis to give a cross-section in which the thickness appears, the cross-section is in a tapered shape and the thickness of the light guide plate at the side confronting the light array increases toward the opposite side facing the document. The light emerging from the light guide plate is high and uniform in light intensity level, so that a CCD unit picks up the light reflected from the document with high accuracy.

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