Fiber optic tap

US4887879A · kind A · utility

Assignee

• The Trustees of Columbia University in the City of New York · US

Inventors

• Paul R. Prucnal · Princeton, US
• Stuart Elby · Westport, US
• Edward Harstead · Park Ridge, US

Key dates

• Filing date: Jan 25, 1988
• Grant date: Dec 19, 1989
• Expiry date: Jan 25, 2008

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B6/4289
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A passive fiber optic tap for a single mode optical fiber is disclosed which utilizes cladding modes induced within the fiber by a microbender. The fiber has a symmetrically circular hour glass shaped notch for tapping radiation from the cladding mode and a detector converts light into an electrical signal. Large tapping ratios, low excess loss and structural compatibility with integrated circuity is obtained.