Search results
Results from the WOW.Com Content Network
Fiber optic sensors are also particularly well suited for remote monitoring, and they can be interrogated 290 km away from the monitoring station using an optical fiber cable. [12] Brillouin scattering effects can also be used to detect strain and temperature over large distances (20–120 kilometers).
Extrinsic fiber optic sensors use an optical fiber cable, normally a multi-mode one, to transmit modulated light from either a non-fiber optical sensor—or an electronic sensor connected to an optical transmitter. A major benefit of extrinsic sensors is their ability to reach otherwise inaccessible places.
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.
In Rayleigh scatter-based distributed fiber optic sensing, a coherent laser pulse is sent along an optic fiber, and scattering sites within the fiber cause the fiber to act as a distributed interferometer with a gauge length approximately equal to the pulse length. The intensity of the reflected light is measured as a function of time after ...
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 ...
One countermeasure of fiber tapping is encryption, to make the intercepted data unintelligible to the thief. [4] Another is to deploy a fiber-optic sensor into the existing raceway, conduit, or armored cable. In this scenario, it can be detected if someone attempts to physically access the data (copper or fiber infrastructure).
As a result of the damping of the light in the quartz glass fibres through scattering, the location of an external physical effect can be determined so that the optical fibre can be employed as a linear sensor. Optical fibres are made from doped quartz glass. Quartz glass is a form of silicon dioxide (SiO 2) with amorphous solid structure ...
A fibre-optic gyroscope (FOG) senses changes in orientation using the Sagnac effect, thus performing the function of a mechanical gyroscope. However its principle of operation is instead based on the interference of light which has passed through a coil of optical fibre , which can be as long as 5 kilometres (3 mi).