Abstract

A temperature-insensitive fiber optic sensor for high-resolution measure of refractive index is proposed and demonstrated. The sensor is based on Fresnel reflection modulated by Fabry–Perot interference, which consists of a section of single-mode fiber (SMF) tip coated with a thin film of SU-8 at the end of the fiber tip. The fringe contrast of the interference spectrum reflected from the sensor head is used to determine the extern RI. The experimental results agree well with the theoretical results and show that the fringe contrast is not sensitive to temperature variation. Such a refractive index sensor can offer the refractive index resolution and accuracy of $5 \times 10^{-6}$ and $5\times 10^{-5}$, respectively. By simultaneous tracking the wavelength shift of the interference pattern, the sensor also has the potential capability for the simultaneous measurement of liquid RI and temperature.

© 2010 IEEE

PDF Article

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription