Spectral, polar and spectral-polar imagers for use in space situational awareness

An imager for imaging a plurality of spatially-correlated images of a single scene over a plurality of disparate electromagnetic wavelength sets representing correspondingly disparate color bands, the apparatus comprising:

• front-end optics configured for outputting a polychromatic, collimated image of a selected scene;
• a first optically-dispersive element spatially situated for receiving the collimated image and dispersing disparate constituent wavelength sets within the received collimated image such that the disparate constituent wavelength sets mutually angularly diverge away from the first optically-dispersive element, wherein the mutual angular divergence of the electromagnetic wavelength sets results from the optical phenomenon of dispersion in which the phase velocity of a wave depends on its frequency such that the paths of the constituent wavelength sets within the received collimated image are bent by the first optically-dispersive element to different angles and the colors represented by the disparate constituent wavelength sets are mutually angularly separated;
• a second optically-dispersive element spatially situated and oriented for receiving the wavelength sets dispersed by the first optically-dispersive element and canceling the mutual angular divergence, while maintaining mutual spatial displacement, among the wavelength sets, wherein the cancellation of the mutual angular divergence imparted by the second optically-dispersive element also results from the optical phenomenon of dispersion;
• and
• an imaging-sensor array configured for registration of the spatially displaced wavelength sets at disparate locations along the imaging-sensor array.