Few-Mode Fiber Characterization System Based on the Spatially and Spectrally Imaging Technique

Abstract

With the widespread use of few-mode fibers, mode characteristics testing becomes essential. In this paper, current few-mode fiber testing techniques are discussed, and the S2 imaging technique is chosen and demonstrated to be capable of few-mode fiber characterization in principle. As a result, the few-mode fiber characterization system with the S2 imaging technique is built and used to obtain accurate mode dispersion of two-mode fibers (a commonly used few-mode fiber) of different lengths. Then, various filters are applied to extract the fundamental and high-order modes to acquire mode coupling components (discrete and distributed mode coupling). The proposed system spectrally characterizes the few-mode fiber by resolving the interference information from the superimposed optical field spatially and has a simple structure and easy operation, which will provide parameter guidance for FMF designing and the FMF sensing experiment optimizing.

In pursuit of high‐fidelity waveguide imaging restoration using deep learning algorithms: A review

“…FMFs find extensive utility in high-capacity transmission [68,69], imaging [70], microwave photonics [71] and optical sensing [72,73]. However, in practice, mode coupling may lead to power exchange and crosstalk [73][74][75]. For instance, the FMF-OCT system is able to enhance image contrast and resolution [76].…”

Application of Crossed Polarizer Method in the Measurement of Differential Group Delay of Optical Fibers

“…The SMF is connected to an optical spectrum analyzer (OSA). The spectral beating ( ) I ω out of modal interference measured by OSA is expressed as follows (detailed derivation can be found in reference [23,34,35]):…”

“…FT reflects the global properties and lacks the capability to map the local features of the signal [36]. Instead, we applied WFT [37] in processing the spectral fringes out of the modal interference where the DGD shows a strong dependence on the wavelength: The spectral beating I(ω) out of modal interference measured by OSA is expressed as follows (detailed derivation can be found in reference [23,34,35]):…”

Optical Imaging, Optical Sensing and Devices

“…The system has practical significance in the field of quasi-distributed strain measurement. Yu et al [ 11 ] propose a few-mode fiber (FMF) characterization system based on the spatial and spectral imaging technique. The proposed system spectrally characterizes few-mode fiber by resolving interference information from the superimposed optical field and has a simple structure and easy operation, providing a guide for the FMF design and the FMF experimental optimization.…”