Title |
Development of Optical Fiber Hydrogen Sensor Based on Polarization-Diversity Loop Configuration Using Pd-Coated Polarization-Maintaining Fiber |
Authors |
Tae-Kyu Noh ; Young-Ho Kim ; Yong-Wook Lee |
DOI |
http://dx.doi.org/10.5207/JIEIE.2013.27.3.001 |
Keywords |
Hydrogen Sensor ; Polarization-Diversity Loop Configuration ; Polarization-Maintaining Fiber |
Abstract |
In this study, we propose a fiber-optic hydrogen sensor using a polarization-diversity loop configuration composed of a polarization beam splitter, two quarter-wave plates, and a polarization-maintaining fiber coated with palladium whose thickness is ∼400nm. One transmission dip of the output interference spectrum of the proposed sensor, chosen as a sensor indicator, was observed to spectrally shift with the increase of the hydrogen concentration, and the sensing indicator showed a wavelength shift of ∼2.48nm at a hydrogen concentration of 4%. Except for a hydrogen concentration of 4%, the response time of the proposed sensor was measured as less than 12.5s and did not show significant dependence on the hydrogen concentration. In particular, the proposed fiber hydrogen sensor is more durable and highly resistant to external stress applied on a transverse axis of an optical fiber, compared with other hydrogen sensors based on side-polished fibers or fiber gratings. |