Multimode Fabry-Perot Interferometer Probe Based on Vernier Effect for Enhanced Temperature Sensing

• Type: Article in International Scientific Journal
• Date: 2019

Authors

Gomes, AD (Author) Other; Becker, M (Author) Other; Dellith, J (Author) Other; Zibaii, MI (Author) Other; Latifi, H (Author) Other; Rothhardt, M (Author) Other; Bartelt, H (Author) Other; Frazao, O (Author) FCUP

Journal

Title: Sensors

Vol. 19

Final page: 453

ISSN: 1424-3210

Publisher: MDPI

Indexing

ISI Web of Knowledge - 14 Citations

Scopus - 14 Citations

Other information

Authenticus ID: P-00Q-57E

DOI: 10.3390/s19030453

Abstract (EN): New miniaturized sensors for biological and medical applications must be adapted to the measuring environments and they should provide a high measurement resolution to sense small changes. The Vernier effect is an effective way of magnifying the sensitivity of a device, allowing for higher resolution sensing. We applied this concept to the development of a small-size optical fiber Fabry-Perot interferometer probe that presents more than 60-fold higher sensitivity to temperature than the normal Fabry-Perot interferometer without the Vernier effect. This enables the sensor to reach higher temperature resolutions. The silica Fabry-Perot interferometer is created by focused ion beam milling of the end of a tapered multimode fiber. Multiple Fabry-Perot interferometers with shifted frequencies are generated in the cavity due to the presence of multiple modes. The reflection spectrum shows two main components in the Fast Fourier transform that give rise to the Vernier effect. The superposition of these components presents an enhancement of sensitivity to temperature. The same effect is also obtained by monitoring the reflection spectrum node without any filtering. A temperature sensitivity of -654 pm/degrees C was obtained between 30 degrees C and 120 degrees C, with an experimental resolution of 0.14 degrees C. Stability measurements are also reported.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9