fiber-optic sensor

Fiber-optic sensor

A sensor that uses thin optical fibers to carry light to and from a location to be probed. In performing the sensing, light can be lost from the fibers or modified in velocity by the action of the phenomena on the fiber. Fiber-optic sensors are ideal for probing in remote or hostile locations, where miniature sensors are required such as in the body, or where extreme sensitivity is required. Two classes of fiber sensors have evolved: intensity sensors, in which the amplitude of light in the fiber is changed during sensing, and interferometric sensors, in which the velocity of light or its phase is modified during sensing. The latter class has proved to be extremely sensitive; intensity sensors are used where moderate performance is acceptable and lower cost is important. Depending on their design, intensity sensors can respond to pressure, temperature, liquid level, position, flow, smoke, displacement, electric and magnetic fields, chemical composition, and numerous other conditions.

Optical interferometry is one of the most sensitive means of detecting displacements as small as 10-13 m. Interferometric fiber sensors apply this technology to sense many physical phenomena. A fiber gyro based on the Sagnac effect is formed by making a fiber loop which, when rotated, causes the light traveling in both directions in the loop to experience different velocities with or against the rotation. A second type of interferometric sensor is constructed by using the Mach-Zehnder interferometer. Sensitivities equal to or surpassing the best conventional technologies have been achieved in these sensors. See Interferometry

McGraw-Hill Concise Encyclopedia of Physics. © 2002 by The McGraw-Hill Companies, Inc.

fiber-optic sensor

[′fī·bər ¦äp·tik ′sen·sər]
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
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In 2018, based on technology, the global the optical chemical sensors market is bifurcated into Infrared Sensors, Fiber-optic Sensor, and others.
A high sensitivity fiber-optic sensor is reached by thinning the optical fiber enough to obtain an evanescent wave interaction of the guided light with the surrounding mediums.
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The elapsed time of 20 [micro]s is equivalent to the round-trip time through the 2 km fiber-optic sensor line.
Ballivy, "Concrete strain monitoring with Fabry-Perot fiber-optic sensor," Journal of Materials in Civil Engineering, vol.
FPGAs allow realizing complex real-time digital signal processing algorithms, and therefore they are ideally suitable for the multichannel PGC technique implementation to demodulate signals from fiber-optic sensor arrays 11].
[4, 5] presented a bending interferometric fiber-optic sensor. They connected two photodiodes to both sides of a microbending fiber-based sensor to measure the output power.
"We're also developing ionic liquids for separation applications in areas such as desulfurization, salt removal and nano-particle conductivity." Other projects include looking for membrane materials for gas separation, which is being pursued for the Natural Gas and Sulfur Utilization Project under the Downstream and Strategic R&D Program; and creating monitoring sensors to assess pipeline integrity, which is being led by one of the group's experts in fiber-optic sensor technology for the Northern Area Pipelines Department.
A new and reportedly unique control system uses a fiber-optic sensor for real-time monitoring and control of both film color and layer thicknesses.

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