Distributed optical fiber chemical sensor

Yatao Yang; Peter A. Wallace; Michael Campbell

doi:10.1117/12.229234

3 January 1996 Distributed optical fiber chemical sensor

Yatao Yang, Peter A. Wallace, Michael Campbell

Proceedings Volume 2594, Self-Calibrated Intelligent Optical Sensors and Systems; (1996) https://doi.org/10.1117/12.229234
Event: Photonics East '95, 1995, Philadelphia, PA, United States

Abstract

Techniques for distributed optical fiber chemical sensor development were investigated and a model system for pH measurement was developed and, as a result, discrete distribution signals were obtained. pH indicator fluorescein sodium was chosen for this work because of its well known properties and high fluorescent intensity. A low temperature sol-gel glass manufacturing process was utilized to immobilize the indicator onto the optical fiber core. Robust porous glass thin film (approximately 1 micrometers ) was grown on the surface of the optical fiber core with indicator molecules entrapped in the matrix. OTDR was employed to obtain the signal at specific positions along the fiber. A dye laser, pumped by a short pulse N₂ laser, produced blue light pulses at 440 nm which were launched into a 1 X 2 optical fiber coupler. A fiber with four sensitive sections was spliced to a 50:50 coupler. The indicator molecules were excited by the blue light via the evanescent wave. Part of the fluorescent light from the indicator molecules was coupled back into the fiber and transmitted back to the coupler. A fast PMT tube was attached to the other arm of the 1 X 2 coupler to detect the fluorescent light. Results were obtained for solutions of various pH value. The system appears to have great potential due to the wide applications in chemical, biochemical, environmental and safety monitoring.

Citation Download Citation

Yatao Yang, Peter A. Wallace, and Michael Campbell "Distributed optical fiber chemical sensor", Proc. SPIE 2594, Self-Calibrated Intelligent Optical Sensors and Systems, (3 January 1996); https://doi.org/10.1117/12.229234

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