The combination of broad-band illumination and coherent (synchronous) detection techniques provides a means by which imaging systems can derive added object information and consequently enhance their resolution. In this paper a unified theory of coherent imaging or holography with broad-band illumination is developed in terms of the temporal impulse response, the spectral frequency response, and cross-correlation imaging with noise illumination of the object. The equivalence of these three methods is established and their resolution capabilities in the imaging of one- and two-dimensional nondispersive objects is determined. The resolution is shown to be dependent on bandwidth and geometry. The advantages of broad-band illumination over monochromatic illumination are also discussed.
© 1977 Optical Society of AmericaPDF Article