Fibre optic reference beam laser Doppler velocimetry

摘要

A compact reference beam laser Doppler velocimeter, constructed using a semiconductor laser diode, optical fibre components and semiconductor detectors, is reported. The device has been designed to overcome many of the problems commonly associated with reference beam configurations. The anemometer may be operated with the laser diode operating in cw and pulsed modes, demonstrating its applicability to wavelength and time division multiplexing schemes for 3D laser Doppler velocimetry. The probe is used to measure the velocity of a spinning disk in the range -20 m/s to +20 m/s.