A white-light fiber-optic interferometer working in the spatial domain, using a special three-peak-wavelength LED as a light source and one of the two arms of the Michelson interferometer as a strain sensor, is presented. Based on the Gaussian spectrum distribution function, a simple spectrum-decomposing method is used to describe the special three-peak-wavelength LED source. Experimental and t...

Distributed fiber-optic vibration sensors receive extensive investigation and play a significant role in the sensor panorama. Optical parameters such as light intensity, phase, polarization state, or light frequency will change when external vibration is applied on the sensing fiber. In this paper, various technologies of distributed fiber-optic vibration sensing are reviewed, from interferomet...

In this paper, a D-dot electric field sensor and a fiber-optic transmission electric field sensor are developed for measurement of electromagnetic pulse. The D-dot sensor is a differential model sensor without source and has a simple structure. The fiber-optic transmission sensor is in the type of small dipole antenna, which uses its outside shielding layer as a pair of antennas. Design of the ...

Fiber optic sensors dispose of some advantages in the field of electrical current and magnetic field measurement, like large bandwidth, linearity, light transmission possibilities. Unfortunately, they suffer from some parasitic phenomena. The crucial issue is the presence of induced and latent linear birefringence, which is imposed by the fiber manufacture imperfections as well as mechanical st...

This paper investigates the influence of material properties on the performance of an optical fiber wound mandrel composite fiber optic interferometer mandrel by using the ANSYS Cad tool, The acoustic sensitivity of an optical fiber considered analytically, High sensitivity obtained with low young modulus, very thick polymer coatings. The thick coating realized by embedding optical fiber in pol...

In this paper, we report the numerical calculations for a thermo-optical model and the temperature sensitivity of a fiber Bragg grating (FBG) sensor. The thermally-induced behaviors of a FBG sensor in the gas nitriding process were analyzed for temperatures ranging from 100–650 ◦C. The FBG consisted of properly chosen photosensitive fiber materials with an optimized thermo-optic coefficient. Th...

Fiber-optic pressure sensors have been developed for measurements of intracochlear pressure. The present family of transducers includes an 81 μm diameter sensor employing a SLED light source and single-mode optic fiber, and LED/multi-mode sensors with 126 and 202 μm diameter. The 126 μm diameter pressure sensor also has been constructed with an electrode adhered to its side, for coincident pres...

A Faraday fiber-optic current sensor was employed to measure the tokamak plasma current. In order to decrease the influence of mechanical perturbations on the sensor sensitivity, a two-pass optical scheme with a variable Faraday mirror at the fiber end is proposed. A decrease, by two orders of magnitude, in the influence of the linear birefringence produced by an external piezoceramic fiber mod...

A novel fiber optic vibration sensor is presented, based on the motion detection of an elastic cantilever by means of the optical triangulation technique. The sensor was designed to work at a fixed frequency of 100 Hz for applications in high power electrical plants where insulation and EM immunity requirements make fiber optic sensing the most suitable choice. The working linear range reaches ...

A non-contact and low-cost nanomaterial based fiber-optic sensor is developed for measuring large values of electric currents. The magnetic field, generated by the electric current, changes the refractive index of a liquid in which nanomaterial particles are suspended. The change of refractive index is converted to a change in the intensity of light transmitted in an evanescent field based fibe...