Open AccessComparison of plane mirror vs retroreflector performance for laser-self-mixing displacement sensors
Author(s) -
Simona Ottonelli,
Francesco De Lucia,
M. di Vietro,
Maurizio Dabbicco,
Gaetano Scamarcio
Publication year - 2009
Publication title -
journal of the european optical society. rapid publications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.357
H-Index - 33
ISSN - 1990-2573
DOI - 10.2971/jeos.2009.09036
Subject(s) - retroreflector , optics , interferometry , tilt (camera) , displacement (psychology) , angular displacement , rotation (mathematics) , physics , cube (algebra) , laser , mixing (physics) , plane (geometry) , plane mirror , beam (structure) , acoustics , mathematics , geometry , psychology , quantum mechanics , psychotherapist
The behavior of a displacement optical sensor based on the Laser-Self-Mixing effect employing a plane mirror (PT) and a solid corner-cube (CC) as moving target is analyzed. The performance of the sensor is compared in terms of simplification of the optical setup, measurement accuracy and tolerance to angular misalignment of the target. On the basis of the innovative assumption that only the fraction of the laser beam orthogonal to the target plane gives rise to the Self – Mixing modulation, it is demonstrated that the interferometer tolerates small tilt of the plane target (up to approximately 0.7◦) only when illuminated by a divergent beam, in which case the displacement measurement becomes affected by a cosine – type error. Instead the corner cube preserves the self-mixing signal over a larger angular range (up to approximately 2◦) at the same time preserving high measurement accuracy