 Michelson and Morley ( 1887 ) and other early experimentalists using interferometric techniques in an attempt to measure the properties of the luminiferous aether , used monochromatic light only for initially setting up their equipment , always switching to white light for the actual measurements . The reason is that measurements were recorded visually . <unk> light would result in a uniform fringe pattern . Lacking modern means of environmental temperature control , experimentalists struggled with continual fringe drift even though the interferometer might be set up in a basement . Since the fringes would occasionally disappear due to vibrations by passing horse traffic , distant thunderstorms and the like , it would be easy for an observer to " get lost " when the fringes returned to visibility . The advantages of white light , which produced a distinctive colored fringe pattern , far outweighed the difficulties of aligning the apparatus due to its low coherence length . This was an early example of the use of white light to resolve the " 2 pi ambiguity " . 
