基于马赫-曾德尔干涉仪的光纤扭转传感器

Optical fiber torsion sensor based on Mach-Zehnder interferometer

提出一种基于马赫-曾德尔干涉仪的扭转传感器,通过实验进行了验证。干涉仪采用无芯光纤-七芯光纤-无芯光纤的结构,当七芯光纤发生扭转时,中心纤芯和外部纤芯的相位差发生变化,使得其透射光谱随之改变。实验结果表明,随着七芯光纤扭转角度的增加,输出光谱的下陷峰向短波长方向偏移,其传感敏感度为0.33nm/(°),角度最小测量精度为0.15°。所提光纤传感器具有成本低、构造简单、制作简便的优点,可以应用于涉及扭转、旋转等的角度测量领域。

A torsion sensor based on Mach-Zehnder interferometer is proposed and demonstrated experimentally.The interferometer is based on the no-core—7-core—no-core structure.When the 7-core fiber is twisted,the phase difference between the central core and the external core changes,which makes the transmission spectrum change accordingly.The results show that the spectra shift towards the short wavelength with the increase of the twist angle of the 7-core fiber.The sensitivity of torsion sensor is 0.33nm/(°),and the minimum measurement accuracy is 0.15°.This torsion sensor has the advantages of low cost,simple structure and simple fabrication.It can be applied to torsion angle or rotation angle measurement fields.