Nonpigtail optical coupling to embedded fiber Bragg grating sensors

Liang Qiu; Keith W. Goossen; Dirk Heider; Daniel J. O'Brien; Eric D. Wetzel

doi:10.1117/1.3421552

1 May 2010 Nonpigtail optical coupling to embedded fiber Bragg grating sensors

Liang Qiu, Keith W. Goossen, Dirk Heider, Daniel J. O'Brien, Eric D. Wetzel

Author Affiliations +

Optical Engineering, Vol. 49, Issue 5, 054402 (May 2010). https://doi.org/10.1117/1.3421552

Abstract

In recent decades, optical fiber has proven useful for many sensor applications. Specifically, fiber Bragg grating (FBG) sensors have shown great utility for integrity management and environmental sensing of composite structures. One major drawback of FBG sensors, however, is the lack of a robust, nonpigtail technique for coupling to the embedded FBG sensor. In this paper, a novel method of free-space passive coupling of light into FBG sensors is described. An angled 45-deg mirror integrated directly into the fiber was used as an input coupling technique. We investigated the application of this approach to both single- and multimode glass fibers containing FBGs. For multimode FBGs, we studied the grating's uniformity across the fiber diameter and its effect on normal free-space coupling. In single-mode investigations, a novel method of coupling to the sensor via splicing a multimode fiber to a single-mode FBG (SMFBG) was developed. Finally, free-space coupling to an embedded SMFBG was employed to measure the tensile strain. Excellent agreement was found between the FBG and conventional electrical resistance strain gauges. We conclude that this coupling method might eliminate the need for pigtailing by providing a more robust coupling method for FBG sensors.

©(2010) Society of Photo-Optical Instrumentation Engineers (SPIE)

Citation Download Citation

Liang Qiu, Keith W. Goossen, Dirk Heider, Daniel J. O'Brien, and Eric D. Wetzel "Nonpigtail optical coupling to embedded fiber Bragg grating sensors," Optical Engineering 49(5), 054402 (1 May 2010). https://doi.org/10.1117/1.3421552

Published: 1 May 2010

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