Search results
Results from the WOW.Com Content Network
Specifically, fiber Bragg gratings are finding uses in instrumentation applications such as seismology, [29] pressure sensors for extremely harsh environments, and as downhole sensors in oil and gas wells for measurement of the effects of external pressure, temperature, seismic vibrations and inline flow measurement. As such they offer a ...
A fiber-optic sensor is a sensor that uses optical fiber either as the sensing element ("intrinsic sensors"), or as a means of relaying signals from a remote sensor to the electronics that process the signals ("extrinsic sensors"). Fibers have many uses in remote sensing.
The optical pulse is attenuated as it propagates along the fiber. For a single mode fiber operating at 1550 nm, a typical attenuation is 0.2 dB/km. [1] Since the light must make a double pass along each section of fiber, this means each 1 km causes a total loss of 0.4 dB. The maximum range of the system occurs when the amplitude of the ...
Time-resolved simulation of a pulse reflecting from a Bragg mirror. A distributed Bragg reflector (DBR) is a reflector used in waveguides, such as optical fibers.It is a structure formed from multiple layers of alternating materials with different refractive index, or by periodic variation of some characteristic (such as height) of a dielectric waveguide, resulting in periodic variation in the ...
Distributed temperature sensing systems (DTS) are optoelectronic devices which measure temperatures by means of optical fibres functioning as linear sensors. Temperatures are recorded along the optical sensor cable, thus not at points, but as a continuous profile. A high accuracy of temperature determination is achieved over great distances.
A fiber-optic current sensor (FOCS) is a device designed to measure direct current. Utilizing a single-ended optical fiber wrapped around the current conductor, [1] FOCS exploits the magneto-optic effect (Faraday effect). [2] The FOCS can measure uni- or bi-directional DC currents up to 600 kA, with an accuracy within ±0.1% of the measured value.
Fibre optic sensors offer complete immunity to RF and microwave radiation with high temperature operating capability, so they can be used for measurement on patients and materials in magnetic resonance scanner (MRI). In strong magnetic fields, there is a small offset in the temperature reading approximately proportional to the strength of the ...
When the incident light beam is at Bragg angle, a diffraction pattern emerges where an order of diffracted beam occurs at each angle θ that satisfies: [3] = Here, m = ..., −2, −1, 0, +1, +2, ... is the order of diffraction, λ is the wavelength of light in vacuum, and Λ is the wavelength of the sound. [4]