Patent · US Expired

Document scanning apparatus

US4422100A · kind A · utility

31Cited by
6References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 8, 1982
Grant dateDec 20, 1983
Priority date
Expiry dateMar 8, 2002

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/193
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An illuminator for a traveling scanner of a document scanning system is disclosed. The illuminator comprises an elliptic-cylindrical surface of about one-half an ellipse in section with a line light source lamp located on one elliptic focal line. The illuminator is positioned so that the line of a document being copied is located at the other elliptic focal line. A reflecting cylindrical light baffle is positioned over the lamp to reflect light that would otherwise not strike the elliptical reflecting surface back through the source and onto the elliptical reflecting surface. The open end of the ellipse is covered with a heat filter to protect the material being copied. The ellipse is set at a relatively small angle, and a perpendicular reflection of material from the document being copied passes through a slot in the heat filter and a slot in the base of the ellipse for further sensing.

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