Research Of Polarization Characteristic In Distributed Optical Fiber White-Light Sensors

The technique which Optical interferometer with low coherence and broad band light drive accomplished physical measurement is called white light interference measuring technique. Its merit is that it can be accomplished measurement of absolute quantities and high accuracy and anti-jamming features. Especially, White light interference measuring technique and optical fiber technology combined and used optical fiber technology, it is easy to achieve multiplexed sensor. So, A kind of typical optical fiber sensing measuring method and technology has been widely applied in all kinds of physical measurement, include of displacement, temperature, strain, deformation, pressure and so on.For optical principle, white light interference which using SLD and LED accomplished are different from Laser driven high polarization of high coherence. Coherent characteristic is partially coherence, its polarization properties may be non-ideal and we called that part polarization. With high coherence similar, polarization transformation also effects the white light interference contrast and interference effect, It will be produce the polarization of the decline problem and influence for measure the resulting.This paper is aimed at polarization decline and compensation methods, This paper discussed distributed optical fiber white light interference measuring technology of the influence of polarization properties and its optimization method,Mainly work in the following aspects:First, this paper gives the recently (2003 by e. Wolf and 2005 by P. Refregier) development part of polarization and partially coherence light theory and establish description method of part polarization and partially coherence light, and discusses its coherence characteristics and gives the polarization degree and Invariant degrees of coherence.Secondly, This paper study that optical fiber produced linear birefringence and circular birefringence cause polarization change model when the fiber squeezing and turned round, we realize optical polarization control method by this effect and completed the full optical fiber polarization controller design and production.Thirdly, The paper constructs distributed optical fiber white strain measurement system, by the reason of polarization influence the interference of fiber optic sensor peak.above results, we are analyze and study for this impact. Above results, sensor torsion produced polarization decline.Finally, We get the fiber white light interference polarization decline compensation method by the use of revolving wave plate and extrusion of optical fiber, And quantitative study for these two methods of white light interference polarization decline of compensation effect. So, we get the distributed optical fiber strain measurement of real-time polarization compensation.Above results, We study that the optical fiber sensing system of polarization and partially coherence light polarization characteristic and the coherence characteristics. We put forward to methods of anti polarization decline, and solves problems for polarization influence of the white light interference measuring optical, We have a solid foundation for distributed optical fiber white strain and functional of temperature measuring system...