A novel fiber optic Fabry-Perot (F-P) current sensor is developed based on magnetic fluid as the medium in F-P interference cavity. A signal demodulation method based on slanted fiber Bragg grating (FBG) wavelength measurement system is proposed. Theory and principle of electromagnetic-controlled refractive index of the magnetic fluid is described, as well as the structure of the sensor system. Preliminary experiments are carried out, and the results indicate that there is a fairly good linearity of the measurement characteristic. The thickness of magnetic fluid film and initial concentration will affect the measurement results.
© 2010 Chinese Optics Letters
(060.2370) Fiber optics and optical communications : Fiber optics sensors
(120.2230) Instrumentation, measurement, and metrology : Fabry-Perot
(120.4630) Instrumentation, measurement, and metrology : Optical inspection
Tao Hu, Yong Zhao, Xing Li, Jingjing Chen, and Zhiwei Lv, "Novel optical fiber current sensor based on magnetic fluid," Chin. Opt. Lett. 8, 392-394 (2010)