Test and calibration methods of laser Doppler anemometers

Abstract

We present a test and calibration methods designed to assess and compare the electro-optical performance and sensitivity of fiber-coupled laser Doppler anemometers (LDAs). For sensitivity analysis and comparison of different LDAs a fiber-coupled test setup that generates precisely frequency-shifted laser pulses, which are fed back into the fiber LDA, is introduced. The efficiency of the optical transceiver system is evaluated by determining the coupling efficiency of the back-reflected beam at the beam waist location into the fiber, employing a flat mirror. This dual approach facilitates a precise characterization of the electro-optical performance and the imaging optics of an LDA.