Patent · US Expired

Bidirectional fiber optic systems

US4709413A · kind A · utility

67Cited by
4References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 13, 1985
Grant dateNov 24, 1987
Priority date
Expiry dateJun 13, 2005

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B6/4204
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A bidirectional fiber optic system is described in which at one terminal the output radiation of a light source (LED or semiconductor laser) is coupled through a small diameter hole in the active area of a photodiode into the core of a larger diameter transmission fiber. On the other hand, radiation propagating through the fiber in the opposite direction exits from the fiber with a large numerical aperture so that most of it is incident on the active area of the photodiode and little is lost through the hole. Also described are a number of photodiode configurations for use in such a system, as well as dual photodiodes to perform both signal detection and output monitoring functions. Further described are fiber optic sensing systems for monitoring such variables as blood pressure.

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