MFD Measurement of a Six-Mode Fiber with Low-Coherence Digital Holography

Abstract

SUMMARY This paper presents an application of low-coherence interferometry for measurement of mode field diameters (MFDs) of a few-mode fiber and shows its performance compared with another method using a mode multiplexer. We found that the presented method could measure MFDs in a few-mode fiber even without any special mode multiplexers.

Spectral Modal Decomposition of Abrupt Fiber Tapers Based on Simulated Annealing Method

“…Modal decomposition techniques are done mostly through rigorous experimental evaluations of fiber's beam profile. Such techniques as S 2 imaging [11], wavefront analysis [12], Realtime mode decomposition [13], and common path interferometry [14], [15] are mostly utilized for the modal decomposition of large-area and multimode fibers. Although these methods provide a vast dynamic range over the modal power extraction and spectrum, they all suffer from hardware misalignments due to free-space optics.…”

Mode Field Diameter Definitions for Few-Mode Fibers Based on Spot Size of Higher-Order Gaussian Mode

“…Several methods have been presented for measuring the MFD of higher-order modes in FMFs from near-field pattern (NFP) [15] or far-field pattern (FFP) [16], [17]. These methods determine the MFD with the help of the second moment of the measured NFP or FFP [18], [19].…”