Multiplexed extrinsic Fabry-Perot interferometers and applications

Kent A. Murphy; Vikram Bhatia; Richard O. Claus; Paul Grems Duncan; Mark E. Jones; Jennifer L. Grace; Jonathan A. Greene; Tuan A. Tran

doi:10.1117/12.219615

15 September 1995 Multiplexed extrinsic Fabry-Perot interferometers and applications

Kent A. Murphy, Vikram Bhatia, Richard O. Claus, Paul Grems Duncan, Mark E. Jones, Jennifer L. Grace, Jonathan A. Greene, Tuan A. Tran

Author Affiliations +

Proceedings Volume 2507, Distributed and Multiplexed Fiber Optic Sensors V; (1995) https://doi.org/10.1117/12.219615
Event: European Symposium on Optics for Environmental and Public Safety, 1995, Munich, Germany

Abstract

Extrinsic Fabry-Perot interferometric (EFPI) sensors have previously been demonstrated for relative strain and temperature measurements for smart structure applications. Inherent difficulties in the signal processing of these devices has created the need for absolute measurement capabilities. In this paper, we present an absolute measurement technique based upon white-light interferometric path matching. The system matches a reference gap to the sensing gap of an EFPI. When the difference of these two lengths is within the coherence length of the source, an intensity envelope is created in the system output. Determination of the corresponding path mismatch indicates the size of the sensor gap and hence strain can be determined. This measurement technique is capable of multiplexing an array of EFPI sensors and data will be presented demonstrating four multiplexed devices. Theoretical considerations for system optimization are also presented. As the only fiber-optic sensors subcontractor to Northrop Corporation on the Navy/Air Force-sponsored Smart Metallic Structures (SMS) program, Fiber & Sensor Technologies (F&S) is developing the optical fiber fatigue gage instrumentation for a multiplexed, in situ structural health monitoring system for aging aircraft. In March, 1995, F&S successfully demonstrated the system on a full-size F/A-18 wing-box spar fully instrumented with 12 of F&S' patented EFPI optical fiber strain gages. F&S is now in process of up-scaling the signal processing system in addition to the optics and intends to demonstrate a second generation multipoint sensor system capable of simultaneously monitoring strains at up to 60 different sites throughout the aircraft later in 1995 or early 1996.

Citation Download Citation

Kent A. Murphy, Vikram Bhatia, Richard O. Claus, Paul Grems Duncan, Mark E. Jones, Jennifer L. Grace, Jonathan A. Greene, and Tuan A. Tran "Multiplexed extrinsic Fabry-Perot interferometers and applications", Proc. SPIE 2507, Distributed and Multiplexed Fiber Optic Sensors V, (15 September 1995); https://doi.org/10.1117/12.219615

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available