Highly sensitive torsion sensor based on a coupled optoelectronic oscillator incorporating nonlinear polarization rotation.

We propose and demonstrate a new, to the best of our knowledge, technique to implement a high-speed and highly sensitive torsion sensor based on a coupled optoelectronic oscillator (COEO) incorporating nonlinear polarization rotation (NPR). The COEO consists of a mode-locked laser loop and an OEO loop. In the laser loop, the NPR effect effectively induces intensity- and wavelength-dependent loss, which acts as a Lyot birefringent fiber filter.

Optical fiber strain sensor with high precision and extended dynamic range based on a coupled optoelectronic oscillator.

We have proposed and experimentally demonstrated an optical fiber strain sensor with high precision and extended dynamic range based on a coupled optoelectronic oscillator (COEO). The COEO is a combination of an OEO and a mode-locked laser, sharing one optoelectronic modulator. The feedback between the two active loops makes the oscillation frequency equal to the mode spacing of the laser.

Enhanced sensitivity of optical fiber vibration sensor based on radio-frequency Michelson interferometer.

We propose and demonstrate a new scheme for enhancing the sensitivity of an optical fiber vibration sensor based on microwave interferometry, which is realized by an incoherent optical Michelson interferometer (MI). The sensing arm of the MI is sensitive to environmental vibration; this will cause changes in the phase of the reflection spectra in the microwave domain. The phase sensitivity can be improved by adjusting the power ratio of the two beams in the interferometer and the driving frequency of the modulator.

Trace copper detection using in-line optical fiber Mach-Zehnder interferometer combined with an optoelectronic oscillator.

We experimentally demonstrate a novel optical fiber chemosensor for trace Cu ions detection that is implemented by using an in-line optical fiber Mach-Zehnder interferometer (MZI) in conjunction with an optoelectronic oscillator (OEO). The MZI is fabricated by lateral offset splicing a section of D-shaped fiber between two single-mode fibers. It splices the broadband optical source into a sinusoidal-shaped light, which can form a single passband microwave photonic filter (MPF) by combining the Mach-Zehnder modulator, a segment of fiber and a photodetector.