  Recent advances in the field of attosecond science hold the promise of
tracking electronic processes at the shortest space and time scales. Imaging
methods that combine attosecond temporal with nanometer spatial resolution are
currently out of reach. Coherent diffractive imaging is based on the
diffraction by a sample of a quasi-monochromatic illumination with a coherence
time that exceeds the duration of an attosecond pulse. Due to the extremely
broad nature of attosecond spectra, novel imaging techniques are required.
Here, we present an approach that enables coherent diffractive imaging with a
broadband isolated attosecond source. The method is based on a numerical
monochromatisation of the broadband diffraction pattern by the regularised
inversion of a matrix which depends only on the spectrum of the diffracted
radiation. Experimental validations in the visible and hard X-rays show the
applicability of the method. Because of its generality and ease of
implementation for single attosecond pulses we expect this method to find
widespread applications in future attosecond technologies such as petahertz
electronics, attosecond nanomagnetism or attosecond energy transfer.
