The setting-up of an optical remote sensing system for target identification: a laboratory experiment

The construction of an optical system for vibration measurement using laser doppler velocimetry (LDV) is presented, the basis of which can be used as a laboratory experiment for the classroom. LDV is an optical technique that can be used to determine an object's velocity by analyzing the frequency content of coherent light reflected from it. It can be used for vibration measurement, target identification, covert surveillance or studying the flow of fluids. The setting up of such a system in the laboratory can sometimes be difficult if it is performed in a nonsystematic way. This paper describes an approach to configuring a free-space optical system and also demonstrates the optical equivalence of cochannel and multipath interference.