Vibration Measurement Based on the Local Maximum Detection Algorithm for Laser Self-Mixing Interferometry

Abstract

A novel laser self-mixing interferometry vibration measurement algorithm based on the local maximum detection technique is proposed, that can reconstruct micro vibrations rapidly and easily. In this article, the principles of the local maximum detection algorithm are analyzed in detail, and the process of solving the window function is emphasized. The major advantage of the method is that it does not involve any complicated calculations and removes the need for optical/electromechanical components. The validity of the presented method is confirmed by means of simulated signals and demonstrated via several experiments for harmonic and aleatory motion.

Laser Self-Mixing Interference: Optical Fiber Coil Sensors for Acoustic Emission Detection

“…However, the sensitivity must still be improved [ is an emerging nondestructive sensing technology and is often used to measure physical parameters such as distance, displacement and velocity [13][14][15][16]. When th nal conditions lead the change of the phase of the feedback light, the output light i of the laser will exhibit interference fringes similar to the Michelson interference such a structure is often called self-mixing interferometer [17][18][19][20]. In a self-mixin ferometer, the mixing interference takes place inside the laser internal cavity.…”

Combined Feature Extraction and Random Forest for Laser Self-Mixing Vibration Measurement without Determining Feedback Intensity

“…The circuit that forms the SMI is illustrated in Figure 1. Combining the Lang-Kobayashi equation [30,31] and other theories [1,32,33], the phase and output power equations of SMI are expressed as follows:…”

“…At 01 C  , assuming that the amplitude of the periodic vibration signal is A and the frequency is f, the distance between LD and the target is denoted as: Combining the Lang-Kobayashi equation [30,31] and other theories [1,32,33], the phase and output power equations of SMI are expressed as follows:…”

A Self-Mixing Microvibration Measurement System of a <i>π</i>-Phase Shifted DFB Fiber Laser

“…During the last decades, many researches were focused on this phenomenon, which can be used to measure the vibration [2], velocity [3], displacements [4] and many physical parameters [5] [6]. Because SMI would produce the intensity variations which can be detected easily by a photodetector (PD), and from this the information of the environment changes could be gotten.…”