Optical Fiber Interferometers Based on Arc-Induced Long Period Gratings at INESC TEC

Sensors

Paulo Caldas¹  Gaspar Rego¹ 

[1] proMetheus, Instituto Politécnico de Viana do Castelo, Rua Escola Industrial e Comercial Nun’Álvares, 4900-347 Viana do Castelo, Portugal;

关键词: long period grating;    optical fiber interferometric sensors;    low-coherence interferometric;    true pseudo-heterodyne technique;   

DOI  :  10.3390/s21217400

来源: DOAJ

【 摘 要 】

In this work, we review the most important achievements of an INESC TEC long-period-grating-based fiber optic Michelson and Mach–Zehnder configuration modal interferometer with coherence addressing and heterodyne interrogation as a sensing structure for measuring environmental refractive index and temperature. The theory for Long Period Grating (LPG) interferometers and coherence addressing and heterodyne interrogation is presented. To increase the sensitivity to external refractive index and temperature, several LPG interferometers parameters are studied, including order of cladding mode, a reduction of the fiber diameter, different type of fiber, cavity length and the antisymmetric nature of cladding modes.

【 授权许可】

Unknown