Research On The Tesing Method And Measurement Technique Of The Fiber Devices Based On White Light Interferometry

In the field of optical fiber communication or sensing,optical fiber path has the advantages of stability,convenient transportation,low transmission loss and easy engineering.In the connection process of the optic optical path,a large number of optical fiber devices will be used and fiber optic device features will ultimately affect the performances of optical path.White light Interferometry has the advantages of high resolution and absolute measurement.Optical fiber device reflection-feature characterization based on the principle of white light interference can possess the advantages of the high sensitivity,the high precision and the high spatial resolution.Based on the principle of white light interferometry,a reflection measuring system of optical fiber device is designed,which can be applied to the distributed characterization of the reflection parameters of optical components.The main research work includes:(1)The range of the delay line in the white light interferometry system limits the measurement range of the device under test.We study the key technology of the delay line range extension.The large-scale delay line range extension scheme,calibration and jointing scheme and application method are studied in detail,and the loss,loss fluctuation and delay precision of large range delay line are discussed.(2)Because the coherent noise in the white light interferometry system will aggravate the system performance parameters,we study the coherent noise suppression,mainly for the internal residual reflection of the optical fiber device and the coherent noise emission suppression method in the optical connection process;(3)Based on the white light interferometry,we have designed the optical fiber device measurement system,and gradually improved the whole optical path of the measurement system.We also proposed a scheme to optimize the parameters of the optical path.Using the measurement system of the structure,the research on the testing methods of some optical fiber devices was carried out,and the parameters related to the reflection characteristics of the optical fiber devices were distributed.Based on the above work,we have constructed a set of optical fiber device reflection characteristic measuring device based on white light interferometry principle.The device can achieve a measurement accuracy of-122 dB,a dynamic range of 95 dB,a measurement accuracy of ?0.6 dB(3?)dB,and a spatial resolution of 19.86 ?m,and an equivalent measurement range of 1.6 meters in the air.