Patent · US Expired

Light guide, line-illuminating device, and image-scanning device

US7088905B1 · kind B1 · utility

10Cited by
13References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 15, 2006
Grant dateAug 8, 2006
Priority date
Expiry dateFeb 15, 2026

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S385/901
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The present invention provides a light guide, a line-illuminating device, and an image-scanning device that provide excellent uniformity in the amount of light produced. A light-reflecting portion comprised of spherical concave surfaces becomes a reflecting surface having spherical convex surfaces when it is seen from the inside of the light guide. Even when the incident angle of light from the light source unit is slightly offset, the reflection angle in spherical convex surfaces significantly changes, and light is reflected uniformly toward the upper surface serving as a light-emitting surface. In particular, when the fine spherical concave portions of the light-reflecting portion have a small depth, the incident light from the end surface is reflected toward the upper surface, serving as a light-emitting surface, and both side surfaces without reflecting back to the light-emitting unit side, so that uniform reflection can be achieved.

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