Share Email Print

Proceedings Paper

Self-mixing feedback Doppler vibrometry
Author(s): Lorenzo Scalise
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Laser Doppler velocimetry uses the Doppler shift of light scattered from moving particles. In self-mixing laser Doppler velocimetry some of the scattered light is allowed to re-enter the laser cavity and here it is mixed with the originally generated cavity mode. This interference results in a fluctuation of the laser intensity with a frequency equal to the Doppler shift (self-mixing interference or back-scattered modulation), according to ?f=2nv(cos?? )/?. Here ?f , n , v, ? and ? stand for the Doppler frequency shift, the refractive index of the medium, the velocity of the scatterer, the angle between the velocity vector and the optical symmetry axis, and the wavelength of the laser light in vacuum. The laser Doppler self-mixing velocimeter has been statically calibrated, using a rotating disk covered with white paper. Authors report about the Doppler signal amplitude of the velocimeter as function of the characteristics and colour of the target surface. Dependence of the Doppler peak amplitude from the target distance and the angle between target and optical axis of the sensor are also reported. Results regarding dynamic characteristics of the sensor are reported and it is shown its capability to be used as a laser Doppler vibrometer.

Paper Details

Date Published: 22 May 2002
PDF: 11 pages
Proc. SPIE 4827, Fifth International Conference on Vibration Measurements by Laser Techniques: Advances and Applications, (22 May 2002); doi: 10.1117/12.468180
Show Author Affiliations
Lorenzo Scalise, Univ. degli Studi di Ancona (Italy)

Published in SPIE Proceedings Vol. 4827:
Fifth International Conference on Vibration Measurements by Laser Techniques: Advances and Applications
Enrico Primo Tomasini, Editor(s)

© SPIE. Terms of Use
Back to Top