A method and computer program product for imaging an object are disclosed. The object is illuminated with an electromagnetic wave, characterized by a spectrum of illuminating wavevectors. Electromagnetic waves scattered by the object are detected, and are characterized by a spectrum of detected wavevectors. An aperture equal to or smaller than an instantaneous characterizing wavelength of the illuminating electromagnetic wave is disposed between the source and the detector. At least one of the illuminating and detected wavevectors is varied in magnitude to provide information regarding a scattering characteristic of the object. By applying a forward model of the aperture to derive a three-dimensional scattering model, a three-dimensional reconstruction of the object may be obtained by inverting a detected data function in terms of the forward model.