High Enhancement Strain Sensor Based on Vernier Effect Using 2-Fiber Loop Mirrors

• Type: Article in International Scientific Journal
• Date: 2020

Authors

Ribeiro Robalinho, PMR (Author) Other; Gomes, AD (Author) Other; Frazao, O (Author) FCUP

Journal

Title: IEEE Photonics Technology Letters

Vol. 32

Pages: 1139-1142

ISSN: 1041-1135

Publisher: IEEE

Indexing

ISI Web of Knowledge - 1 Citation

Scopus - 2 Citations

Other information

Authenticus ID: P-00S-JHZ

DOI: 10.1109/lpt.2020.3014695

Abstract (EN): In this letter, a strain sensor with high sensitivity enhancement using a special case of Vernier effect is presented. The sensor configuration is composed of two-fiber loop mirrors in a cascaded configuration with opposite strain responses when individually characterized. Thus, the enhanced Vernier effect is explored, which is the most sensitive of three possible cases Vernier effect. Here, the Vernier response depends on the difference between the sensitivities of each Hi-Bi optical fiber. In addition to this, the fundamental and the first harmonic were also explored. The results obtained are a strain sensitivity of (13.3 +/- 0.3) pm/mu epsilon for the carrier, (80.0 +/- 0.3) pm/mu epsilon or the Vernier envelope of the fundamental case and (120 +/- 1) pm/mu epsilon for the Vernier envelope of the first harmonic. The first harmonic could achieve a magnification factor of 8. Considering that the optical interrogation system allows a minimum resolution of 0.02 nm, the minimum measurement step achievable is 0.2 mu epsilon. This work proves the possibility of applying the concept of enhanced Vernier effect to fiber loop mirrors, obtaining higher sensitivity than a standard fiber loop mirror alone. Besides, the sensitivity can be increased through the usage of harmonics of the Vernier effect. Moreover, the use of large interferometers allows a better discretization of the envelope, which implies a greater ease of analysis.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 4