Journal of the European Optical Society - Rapid publications, Vol 4 (2009)

Comparison of plane mirror vs retroreflector peformance for laser-self-mixing displacement sensors

S. Ottonelli, F. De Lucia, M. di Vietro, M. Dabbicco, G. Scamarcio


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 performances of the sensor are 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.

© The Authors. All rights reserved. [DOI: 10.2971/jeos.2009.09036]

Full Text: PDF

Citation Details

Cite this article


S. Donati, Electro-Optical Instrumentation Chapter 4 (Prentice Hall, Upper Saddle River, NJ, 2004) .

G. Giuliani, M. Norgia, S. Donati, and T. Bosch, "Laser diode selfmixing technique for sensing applications" J. Opt. A: Pure Appl. Opt. 4, S283-S294 (2002).

G. A. Acket, D. Lenstra, J. Den Boef, B. H. Verbeek, "The influence of feedback intensity on longitudinal mode properties and optical noise in index-guided semiconductor lasers" IEEE J. Quantum Electron. 20, 1163-1169 (1984).

S. Ottonelli, F. De Lucia, M. di Vietro, M. Dabbicco, G. Scamarcio, and F. P. Mezzapesa, "A Compact Three Degrees-of-Freedom Motion Sensor Based on the Laser-Self-Mixing Effect" IEEE Phot. Technol. Lett. 20, 1360-1362 (2008).