Simultaneous measurement of multiple target displacements by self-mixing interferometry in a single laser diode

Dipartimento Interateneo di Fisica, Università degli Studi e Politecnico di Bari, via Amendola 173, I-70126 Bari, Italy.
Optics Express (Impact Factor: 3.49). 08/2011; 19(17):16160-73. DOI: 10.1364/OE.19.016160
Source: PubMed


We demonstrate that a single all-optical sensor based on laser diode self-mixing interferometry can monitor the independent displacement of individual portions of a surface. The experimental evidence was achieved using a metallic sample in a translatory motion while partly ablated by a ps-pulsed fiber laser. A model based on the Lang-Kobayashi approach gives an excellent explanation of the experimental results.

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