Dopplergraph

The word dopplergraph is a combination of the words doppler and photograph. Dopplergraphs are two-dimensional records of variations in the doppler shift in light intensity. Dopplergraphs do not need to be a record of the shift of visible light, but of any radiated wave, which includes electromagnetic waves and acoustic waves. Since the doppler shift is caused by the velocity of the radiating source towards or away from the viewer, a dopplergraph is a picture of the velocities associated with the sources being viewed.