How to classify fiber optic sensors

Fiber optic sensors can be divided into two categories: one is functional (sensor type) sensor; the other non-functional (light transmission type) sensor.

Sensor is the use of functional characteristics of the optical fiber itself as the sensing element, was measured for optical fiber transmission of light is modulated, so that the intensity of transmitted light, phase, frequency or polarization properties of such a change, now go through to be modulated conduction demodulation, to arrive at the measured signal.

Optical fiber in which only optical media, but also sensitive components, optical modulation in optical fiber is measured, the use of multi-mode fiber.

Advantages: Compact, sensitivity degrees. Disadvantages: have to use a special fiber, and high cost. Typical example: FOG, such as fiber-optic hydrophone.

Sensors is the use of non-functional experience other sensitive components to be measured changes, optical transmission medium for information only, often using single-mode fiber. Fiber optic light guide in which only play the role of light in fiber optic sensor based on the measured modulation.

Advantages: No special fiber, and other special techniques, relatively easy to implement, low cost. Disadvantages: low sensitivity. The most practical fiber-optic sensors are non-functional

Currently there are 70 kinds of fiber optic sensors have been, fiber optic acoustic sensor is an optical fiber sensor itself. When the fiber is very small by some external force, it will have slightly curved, and its light transmission ability to change a lot. Sound is a mechanical wave, its role is to make optical fiber and the bending force, will be able to get sound through the bending strength. FOG is a fiber-optic sensor itself. Compared with the laser gyro, fiber optic gyro, high sensitivity, small size, low cost, can be used for aircraft, ships, missiles and other high-performance inertial civil aviation system.