Specklegram in a grapefruit fiber and its response to external mechanical disturbance in a single-multiple-single mode fiber structure.
Specklegram in multimode fiber has successfully been used as a sensor for detecting mechanical disturbance. Speckles in a multimode pure silica grapefruit fiber are observed and compared to that of a step-index multimode fiber, showing different features between them. The sensitivities to external disturbance of two kinds of fiber were measured, based on single-multiple-single mode (SMS) fiber structure. Experimental results show that the grapefruit fiber shows higher sensitivity than does the step-index multimode fiber. The transmission spectrum of the grapefruit fiber was measured as well, showing some oscillation features that are significantly different from that of a step-index multimode fiber. The experiments may provide suggestions to understand the mechanisms of light propagation in grapefruit fibers.
Wang
Yuntao
Y
Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P.O. Box 800211, 201800, Shanghai, China.
Cai
Haiwen
H
Qu
Ronghui
R
Fang
Zujie
Z
Marin
Emmanuel
E
Meunier
Jean-Pierre
JP