Share Email Print

Proceedings Paper

Optical fibre PH sensor based on immobilized indicator
Author(s): Defu Cai; Qiang Cao; JingHong Han; Jine Cai; YaTing Li; ZeMin Zhu; Jie Fan; Ning Gao
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

An optical fiber pH sensor which has the immobilized pH sensitive indicator dye reagents on the tip of the optical fiber has been studied. The probe is made by covalently immobilizing the phenol red, bromine phenol blue, or bromothymol blue on the polyacrylamide microsphere fixed by polyterafluoroethylene (PTFE) film. A gap between the dye and optical fiber was used to make the diffusion of the hydrogen ions easier. The parameters of the optical fiber pH sensor have been given completely. The ranges of measurement are 3.0 - 5.0 pH, 7.0 - 8.5 pH, and 8.0 - 10.0 pH for bromine phenol blue, phenol red, and bromothymol blue, respectively. The sensitivity is 66.6 mV/pH. The probe has a precision of better than 0.55 pH. The linear correlation coefficient is 0.999. The response time is 1 - 2 min. The hysteresis is 0.52%. The repeatability is 0.013 mV, while the stability is 0.015 pH/h.

Paper Details

Date Published: 1 August 1991
PDF: 6 pages
Proc. SPIE 1572, International Conference on Optical Fibre Sensors in China OFS(C) '91, (1 August 1991); doi: 10.1117/12.50038
Show Author Affiliations
Defu Cai, Institute of Electronics (China)
Qiang Cao, Institute of Electronics (China)
JingHong Han, Institute of Electronics (China)
Jine Cai, Institute of Electronics (China)
YaTing Li, Institute of Electronics (China)
ZeMin Zhu, Institute of Electronics (China)
Jie Fan, Institute of Electronics (China)
Ning Gao, Institute of Electronics (China)

Published in SPIE Proceedings Vol. 1572:
International Conference on Optical Fibre Sensors in China OFS(C) '91
Brian Culshaw; Yanbiao Liao, Editor(s)

© SPIE. Terms of Use
Back to Top