Two-point chirp laser Doppler velocimeter using a powerful fibre-coupled green Nd: YAG ring laser

  • J. Czarske
Conference paper

Abstract

The chirp heterodyne technique allows the directional discrimination of laser Doppler velocity measurements without additional frequency shift elements. This paper presents, for the first time, the use of a chirp-frequency-modulated solid-state-laser, emitting in the green spectral range. The advantage of the chirp heterodyne technique compared to other concepts is, that a single laser source suffices for the directional measurements of multiple component velocities simultaneously. Velocity measurements at two different measurement points are presented.

Keywords

optical velocity measurement technique laser frequency modulation optical fibre delay line quadrature demodulation signal processing technique two-point velocity measurement 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • J. Czarske
    • 1
  1. 1.Laser Zentrum Hannover e. V. (LZH)HannoverGermany

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