Optical Doppler shift measurement using a rotating mirror

Abstract

Optical Doppler shift experiments are not simple because the light source cannot easily be moved in a sufficiently smooth and uniform manner to keep the level of noise well below that of the signal. Thus, most Doppler shift experiments are performed with sound or microwaves. Instead of using a moving mirror to produce a moving light source, we use a rotating mirror in which one beam is reflected from the advancing side and the other beam is reflected from the receding part of a rotating mirror. This arrangement can overcome many noise generating effects.