High-sensitivity optical fiber refractive index sensor using multimode interference structure

IEICE Electronics Express

Yoshiki Matsumoto¹  Shuji Taue¹  Hideki Fukano¹ 

[1] The Graduate School of Natural Science and Technology, Okayama University

关键词: MMI;    multimode interference;    optical fiber sensor;    refractive index sensor;   

DOI  :  10.1587/elex.9.302

学科分类：电子、光学、磁材料

来源: Denshi Jouhou Tsuushin Gakkai

【 摘 要 】

References(7)Cited-By(5)This letter presents the experimental investigation to increase the sensitivity of an optical fiber refractive index sensor with a multimode interference (MMI) structure. It is confirmed that the interference wavelength can be set in the long-wavelength region by adjusting the sensing-part length. Moreover, it is shown that the fineness of the cores in the input and output fibers is essential to obtain a sharp interference signal. We demonstrate the high sensitivity of an MMI-structured optical fiber sensor by applying it to refractive index measurements of ethanol/water solutions. This refractive index sensor reveals a resolution as fine as 1.8 × 10-5, which is the highest value so far reported in this type and has one order higher sensitivity than a commercially available Abbe refractometer (∼ 10-4).

【 授权许可】

Unknown