Fiber optic temperature sensors for small-scale heat sources have an urgent need in many industrial fields. We first propose and demonstrate an ultra-short fiber optic temperature sensor based on a Fabry-Perot (FP) interferometer which combines a fiber Bragg grating (FBG) with Fresnel reflection on the fiber end face. The FBG with a grating length of 50 μm was inscribed by a femtosecond laser line-by-line scanning technology. This FBG exhibits a resonant wavelength of 1548.8 nm and a broad full width at half maximum (FWHM) bandwidth of 12.4 nm. The selected dip wavelength of the FBG-FP cavity sensor changes linearly with the temperature increase, corresponding to the temperature sensitivity of 10.8 pm/°C. Moreover, the FBG-FP cavity sensor can be used to measure the temperature of the small-scale laser spot due to its compact structure. The experimental results show the temperature at different positions of laser exposure area are 138.4 °C, 111.5 °C and 74.4 °C, respectively.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
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.