COHERENCE PROPERTIES OF SOME BROAD-BAND HIGHLY COHERENT-LIGHT FIELDS

Coherence properties are studied for nonsinusoidal steady-state light fields, which have the property, that they produce nonsinusoidal traveling waves with the same time-dependent waveform throughout the far field of their sources. It is found that many such deterministic light fields can have frequency bandwidths that more than span the visible spectrum and can produce interference fringes with unit visibility if light from any pair of points in the far field is combined. However, the complex degree of coherence (in the space-time domain) for such fields over the far field is not unimodular. Thus these fields are not perfectly coherent according to the usual definition within the theory of partial coherence.