Self-mixing speckle interference in DFB lasers

Abstract

Theoretical analysis and experimental results of self-mixing speckle interference in a distributed feedback (DFB) laser are presented in this paper. Self-mixing speckle interference occurs when external optical feedback comes from a moving rough surface. Dynamic output variations in the DFB laser as well as their probability density functions (PDFs) are analyzed on the basis of speckle theory and self-mixing interference in the DFB laser. Numeric simulations and experiments are in agreement with each other. The both results show that self-mixing speckle interference in DFB laser can be used to measure velocity of target.

Self-Mixing Thin-Slice Solid-State Laser Metrology

“…The LDV system, which utilizes the self-mixing modulation effect in semiconductor lasers, has been applied to vibrometry [66–68], speckle pattern interferometry [69], and measurements of the “average” velocity and flow of small particles and red-blood cells [16,17,21–23,70,71]. …”

Obtaining High Fringe Precision in Self-Mixing Interference Using a Simple External Reflecting Mirror

“…The optic path is very simple and self-aligning such that the reference path is not required. In recent decades, this SMI effect based on solid-state laser [1], vertical cavity surface emitting laser (VCSEL) [2], distributed feedback laser (DFB) [3], and fiber laser [4] has been widely studied. The SMI signals can carry the information of the target; therefore, this technique has been used for a wide variety of measurements, including velocity [5], absolute distance [6], displacement [7], vibration [8], and thickness [9].…”

Numerical simulation and experimental study of self-mixing speckle generated in an erbium-doped fiber ring laser

“…LSMS represents self-mixing speckle signal, when the rough surface is moving, it can used for dynamic measurement. To our knowledge, it has been use for velocity and displacement measurement [1][2][3][4][5][6][7]. In the previous researches, the characteristic of self-mixing speckle signal and the methods of signal analysis were discussed.…”