Self-mixing Sensor for Real-time Measurement of Harmonic and Arbitrary Displacements

Usman Zabit (1) , Olivier Bernal (1) , Thierry Bosch (1)

1 LAAS-OSE - Équipe Optoélectronique pour les Systèmes Embarqués

A real-time self-mixing laser displacement sensor is presented that uses a fast consecutive-samples based unwrapping algorithm. The processing is achieved at a rate of 125KHz by an integrated micro-converter (ADuC7020) embedded on the SM sensor. Arbitrary and harmonic displacements have been measured in real-time with λ /10 precision as compared with the reference built-in capacitive feedback sensor of the target, where λ is the laser wavelength. The algorithm does not require any parameter estimation or huge memory and corrects possible false fringe detections. This results in a compact, integrated, precise and self-aligned laser sensor that costs less than 40 $.

Mots clés: real-time; displacement sensor; self-mixing interferometry; optical sensor

Domaines: Optique / photonique

Usman Zabit, Olivier Bernal, Thierry Bosch. Self-mixing Sensor for Real-time Measurement of Harmonic and Arbitrary Displacements. IEEE International Instrumentation and Measurement Technology Conference (I2MTC 2012), May 2012, Graz, Austria. 5p., ⟨10.1109/I2MTC.2012.6229702⟩. ⟨hal-00708480⟩