Mode coupling evaluation method and mode coupling evaluation device

摘要

PROBLEM TO BE SOLVED: To provide a technique for improving the accuracy of the evaluation of the production process, the characteristics and the like, of an optical cable.;SOLUTION: In a mode-coupling evaluation device 10, an interferometer 14 interferes a linearly-polarized light excited to BF 13 with a mode coupled linearly-polarized light. A optical path limiting device 15 generates an optical path difference between the excited linearly-polarized light and mode coupled linearly-polarized light at the interferometer 14. A light receiver 16 detects an interfering light and performs O/E conversion. An optical modulator 17 modulates the interfering light. A mode coupling coefficient calculation device 19 obtains a power spectrum to the longitudinal distribution of the signal of the interfering light, between the excited linearly-polarized light and the mode coupled linearly-polarized light based on the signal output from a signal processing-recording device 18, and calculates the spatial frequency dependence of the mode-coupling coefficient.;COPYRIGHT: (C)2010,JPO&INPIT