Distributed optical fiber white light interference sensor array based on adjustable Fabry-Perot resonant cavity

Abstract

The invention provides a distributed fiber white-light interference sensor array based on tunable Fabry-Perot resonant cavity, which is composed of a duplex photoelectric device, a tunable Fabry-Perotresonant cavity, a single-mode connection fiber and a sensor, wherein the tunable Fabry-Perot resonant cavity is composed of a scanning prism, a self-focusing lens, and a single-mode optical fiber with partial reflection surface; the duplex photoelectric device is composed of a wide-spectrum light source with a common base, an emitter and a collector, a photodetector, and a beam splitter prism; the beam with a certain spectral width is emitted by the light source to the resonant cavity directly through the beam splitter prism and is reflected multiple times by the left and the right surfacesof the resonant cavity to obtain a signal light; and the signal light outputted from the right cavity surface enters the sensor through the single-mode connection fiber, reflected by the left and theright end faces of the sensor, returns along the original path to the resonant, and is outputted from the left cavity surface to the photodetector. The distributed fiber white-light interference sensor array has a common light path structure and has the advantages of good temperature stability, simplest optical fiber path structure, low cost and high practicality.

Description

(1) Technical field [0001] The present invention relates to the field of optical fiber technology, in particular to a distributed optical fiber white light interference sensor array for interrogating multiple sensor signals based on an adjustable Fabry-Perot resonant cavity length. (2) Background technology [0002] Fiber-optic interferometers driven by low-coherence, broadband light sources such as light-emitting diodes (LEDs), superspontaneous emission sources (ASE) or multimode laser diodes are often referred to as white-light fiber interferometers. A typical fiber optic white light interferometer such as figure 1 As shown, its structural composition is to use optical fiber to build a Micheslon interferometer, and use a wide-spectrum light source LED or ASE to drive the interferometer to provide light energy, and use the detector to detect white light interference fringes to achieve the measurement of the physical quantity to be measured. Its working principle is as foll...

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Problems solved by technology

However, because it does not have a common optical path structure, it is easily affected by environmental factors (such as temperature and vibration), resulting in inconsistent changes in the optical path of the two optical paths, which affects the demodulation of the sensor signal and reduces the signal resolution of the interferometer. Adjusting the sensitivity will reduce the measurement accuracy, and the long-term stability and reliability cannot be guaranteed; at the same time, the structure of the interferometer is relatively complicated, which is not suitable for the practical application of the interferometer.

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