Strain and temperature measurement using a 9.5-m continuous chirped fiber Bragg grating with millimeter resolution

Abstract

A 9.5-m continuous chirped fiber Bragg grating (CFBG) interrogated with an optical frequency domain reflectometer is used for strain and temperature measurements. The spatial resolution is 4 mm and the noise level is 0.1 K corresponding to 1 μstrain. The strain profile is also derived from the optical reflection spectrum alone, and the results are in good agreement with the profile obtained from the optical frequency domain reflectometer. A CFBG in combination with a high-resolution interrogator can therefore enable a cost-efficient continuous strain sensor.