南京师范大学物理科学与技术学院, 江苏 南京 210023
通过在激光反馈干涉(LFI)系统中引入衍射光栅,提出了一种基于利特罗结构的激光反馈光栅干涉(LFGI)技术,用于一维和二维精密位移的测量。半导体激光器出射的光束以利特罗条件入射至反射式全息光栅,衍射光沿入射光方向返回激光腔后,腔内会发生激光反馈干涉效应。引入正弦相位调制解调技术,高精度地测量一维和二维微位移。利特罗结构和LFGI系统具有自准直性好、结构紧凑、易于操作和系统稳定性高的优点。实验结果表明,利特罗式LFGI系统的位移测量精度可以达到10 nm量级。
测量 位移测量 自混合干涉 衍射光栅 利特罗结构 正弦调制
Author Affiliations
Abstract
Jiangsu Key Laboratory on Opto-Electronic Technology, School of Physical Science and Technology, Nanjing Normal University, Nanjing 210023, China
A fiber in-line Fabry–Pérot interferometer is presented. The sensing head consists of a micro ellipsoidal air cavity and a small section of solid-core photonic crystal fiber. The reflective index (RI) and temperature can be interrogated simultaneously through a fast Fourier transform and by tracing the dip wavelength shift of the reflective spectrum. Experimental results show that the RI amplitude and wavelength sensitivities are 5.30/RIU and 8.46×10 1 nm/RIU in the range from 1.34 to 1.43, and the temperature amplitude and wavelength sensitivities are 6.8×10 4/°C and 2.48×10 3 nm/°C in the range from 15°C to 75°C, respectively. Easy fabrication, a simple system, and simultaneous measurement make it appropriate for dual-parameter sensing application.
280.4788 Optical sensing and sensors 060.2370 Fiber optics sensors Chinese Optics Letters
2016, 14(5): 050601
Author Affiliations
Abstract
Jiangsu Key Lab of Opto-Electronic Technology, School of Physical Science and Technology, Nanjing Normal University, Nanjing, 210023, China
Micro-displacement measurement based on self-mixing interference using a fiber laser system was demonstrated. The sinusoidal phase modulation technique was introduced into the fiber laser self-mixing interference measurement system to improve the measurement resolution. The phase could be demodulated by the Fourier analysis method. Error sources were evaluated in detail, and the system was experimentally applied to reconstruct the motion of a high-precision commercial piezoelectric ceramic transducer (PZT). The displacement measurement resolution was well beyond a half-wavelength. It provides a practical solution for displacement measurement based on all optical-fiber sensing applications with high precision.
Self-mixing interference micro-displacement sensing phase modulation fiber laser Photonic Sensors
2014, 4(4): 379–384
