Fiber Optic Temperature Sensor How It Works

Fiber optic sensors work based on the principle that light from a laser or any superluminescent source is transmitted via an optical fiber experiences changes in its parameters either in the optical fiber or fiber bragg gratings and reaches a detector which measures these changes.

Fiber optic temperature sensor how it works.

Light is sent to the end of a fiber via a fiber coupler and received by a photodiode phototransistor. The most popular is probably the diaphragm design. If an object appears in front of the sensing end of a bifurcated fiber optic light from one branch will be reflected off the object and back to the receiver through the other branch. Unlike traditional electrical temperature measurement thermocouples rtd the length of the fiber optic cable is the temperature sensor.

It depends on the type of sensor. The fibre optic cable can be 30 km in length is passive in. 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.

It consists of a laser source to emit light. Depending on the application fiber may be used because of its small size or because no electrical power is needed at the. Figure 1 schematic of step index optical fibre. A beam splitter made of glass plate is inclined at an angle 45 0 with respect to the direction of the.

They are basically just a regular fiber with a diaphragm on the end that is normal to the fiber. It is based on the principle of interference between the beams emerging out from the reference fiber and the fiber kept in the measuring environment. Optical fibres an optical fibre consists of a thin low loss glass wire with a centre or core region having a slightly higher refractive index than its surrounding region or cladding. Distributed temperature sensing dts measures temperature distribution over the length of an optical fiber cable using the fiber itself as the sensing element.

This allows a single sensor to both illuminate and view an object through the same fiber optic assembly. Of optical fibres and each type of sensors. Intensity based fiber optic sensors require more light and these sensors use a multi mode large core fibers the shown figure gives an idea about how the light intensity work as a sensing parameter as well as how this arrangement makes the fiber to work as a vibration sensor. As the pulse travels along the length of the fiber optic it interacts with the glass.