Directional discrimination in the self-mixing type laser Doppler velocimeter.

A simple and inexpensive method of directional discrimination of velocity based on the analysis of the Doppler signal's waveform obtained through a self-mixing type laser Doppler velocimeter (LDV) is described. The technique does not need the components commonly used to give the frequency offset required to yield directional information in LDV. The device is described, and experimental evidence is presented.