title: Twist sensor based on axial strain insensitive distributed Bragg reflector fiber laser.
abstract: A novel fiber-optic twist sensor based on a dual-polarization distributed Bragg reflector (DBR) fiber grating laser is proposed and experimentally demonstrated. By beating the signal between the two polarizations of the laser which operates at 1543.154 nm, a signal of 30.78 MHz in frequency domain is observed. The twist will change the fiber birefringence, and resulting in the beat frequency variation between the two polarization modes from the fiber laser. The result shows the beat frequency shifts as a Sinc function curve with the twist angle and both the measuring curve period and twist sensitivity depend on the twist length of the laser cavity. A high twist sensitivity of 6.68 MHz/rad has been obtained at the twist length of 17.5 cm. Moreover, the sensor is insensitive to the environmental temperature, as well as strain along the fiber axis with ultralow beat frequency coefficients, making temperature and axial strain compensation unnecessary.
authors.affiliation: Huazhong University of Science and Technology, College of Optoelectronic Science and Engineering, Wuhan National laboratory for Optoelectronics, Wuhan 430074, China.
authors.forename: Jianghai
authors.initials: J
authors.lastname: Wo
authors.forename: Meng
authors.initials: M
authors.lastname: Jiang
authors.forename: Maxime
authors.initials: M
authors.lastname: Malnou
authors.forename: Qizhen
authors.initials: Q
authors.lastname: Sun
authors.forename: Jiejun
authors.initials: J
authors.lastname: Zhang
authors.forename: Perry Ping
authors.initials: PP
authors.lastname: Shum
authors.forename: Deming
authors.initials: D
authors.lastname: Liu
mesh_terms: D055119:Elastic Modulus; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005336:Fiber Optic Technology / Q000295:instrumentation*; D012031:Refractometry / Q000295:instrumentation*; D019415:Torque; D014160:Transducers, Pressure