Explain working of Laser Doppler Vibrometer with diagram.

A laser-Doppler vibrometer identifies the Doppler effect or shift of laser light reflected from the sample object

Explanation:

A laser-Doppler vibrometer (e. g. Micro Motion Analyzer 400 from Polytec) identifies the Doppler effect or shift of laser light reflected from the sample object. At a beam splitter, a laser beam is partitioned into a measuring beam and a reference beam that deflects 90 ° upwards and transmit to the reference mirror "RM." Both beams come back to the beam splitter.