Performance improvement of discriminative distributed Brillouin fiber sensing of temperature/strain

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K14999
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 21030:Measurement engineering-related
• Research Institution: Toyota Technological Institute
• Principal Investigator: Okawa Youhei 豊田工業大学, 工学(系)研究科(研究院), ポストドクトラル研究員 (90835737)
• Project Period (FY): 2019-04-01 – 2021-03-31
• Keywords: ブリルアン散乱 / 光ファイバ / 分布計測 / グレーティング

Outline of Final Research Achievements

Brillouin dynamic gratings (BDGs) generated by stimulated Brillouin scattering in an optical fiber are expected to be used for optical sensing and signal processing because they can be rewritten at high speed by light. In this study, we have improved the spatial resolution of discriminative and distributed measurement of temperature/strain using BDG reflection along a polarization-maintaining fiber. In addition, by exploring the measurement principle of the optical correlation-domain method, which is the distributed measurement technique used in this study, we have developed a method of controlling Brillouin gain coherently and a new distributed measurement method based on computed tomography.

Free Research Field

非線形光学

Academic Significance and Societal Importance of the Research Achievements

「光ファイバ神経網」による構造物の健全性診断技術では、歪だけでなく温度変化があるのが普通であり、これらの分離は極めて重要である。本研究で扱う、偏波保持ファイバ中のブリルアンダイナミックグレーティングを利用する手法は、高い精度で温度と歪の分離が可能である。この手法の基礎現象から解析し性能向上する本研究は、先端光計測技術として重要であるだけでなく学術的にも意義が大きいと考える。