Assessment of Self-Mixing Interferometric Technique for Displacement Sensing

Self-mixing interferometric (SMI) technique has demonstrated its effectiveness in achieving precise and contactless measurements of submicron displacements. Comprehensive assessments of its effectiveness in displacement sensing, particularly in scenarios involving dynamic targets with varying displacements and frequencies remain as a gap. In this work, we introduce an optoelectronic testbed that includes the fundamental setup of the self-mixing interferometer, incorporating a controllable piezoelectric actuator as the target to assess the effectiveness of the SMI technique in sensing the displacement. We provide detailed insights into the construction of the transimpedance-amplifier and calibration parameters of the optoelectronic setup. Utilizing the proposed testbed, our experiments demonstrate the capability to sense displacements within the range of 0.325 μm to 2.925 μm. Our study significantly advances the understanding of the SMI technique's applicability in displacement sensing, particularly in dynamic scenarios, highlighting its potential as an adaptable and effective technique for submicron displacement measurements across diverse applications and fields.