Abstract
We introduce an evanescent-wave-spectroscopic fiber optic pH sensor. This sensor has part of the polymer cladding doped with either congo red (CR), which responds to pH=3 to 5, or methyl red (MR), which responds to pH=5 to 7, as the pH sensor film. In this study we succeeded in expanding the measurable pH range by using two pH sensor probes with the different pH sensitivities. In addition making the pH fiber sensor into a probe structure enabled us to achieve high pH sensitivity and to monitor the pH value easily. Reducing the quantity of doped dye made it possible to use the sensor for objects highly sensitive to pH chemical equilibrium.
| Original language | English |
|---|---|
| Pages (from-to) | 2902-2905 |
| Number of pages | 4 |
| Journal | Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers |
| Volume | 36 |
| Issue number | 5 A |
| DOIs | |
| Publication status | Published - 1997 May |
| Externally published | Yes |
Keywords
- Congo red
- Evanescent wave spectroscopy
- Fiber sensor
- Methyl red
- pH sensor
ASJC Scopus subject areas
- Engineering(all)
- Physics and Astronomy(all)