Patent · US Expired

Distributed refractive index type optical transmission plastic article and method of manufacturing the same

US5175786A · kind A · utility

5Cited by
5References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 29, 1991
Grant dateDec 29, 1992
Priority date
Expiry dateMay 29, 2011

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B6/02038
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A distributed refractive index type optical transmission plastic article has a circular cross section of a radius r.sub.0 between 0.4 and 0.6 mm. A refractive index distribution of the optical transmission article substantially approximates predetermined ideal refractive index distribution curve at least in a range of 0.25r.sub.0 to 0.70r.sub.0 extending from a center axis toward a peripheral face of the article. The article has a refractive index n.sub.0 between 1.4 and 1.6 for its central part, a refractive index distribution constant between 0.3 and 0.7 mm.sup.-1, and a modulation transfer function (MTF) of at least 55%. This optical transmission article is made from uncured liquid substances each having a viscosity between 10.sup.3 and 10.sup.8 poises and refractive indexes n of n.sub.1 >n.sub.2 >n.sub.3 . . . n.sub.N when cured. N (N.gtoreq.3) of such uncured liquid substances are arranged in such a way that the refractive indexes n successively decrease from a central portion toward a peripheral portion, and concentrically laminated one upon the other to form an uncured strand fiber. The substances between adjacent layers of the fiber are mutually diffused, and at the same ti…

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