Computational Microscopy beyond Perfect Lenses

We demonstrate that in situ coherent diffractive imaging (CDI), which harnesses the coherent interference between a strong and a weak beam illuminating a static and dynamic structure, can be a very dose-efficient imaging method. At low doses, in situ CDI can achieve higher resolution than perfect lenses with the point spread function as a delta function. Both our numerical simulation and experimental results show that the combination of in situ CDI and ptychography can reduce the dose by two orders of magnitude over ptychography. We expect that computational microscopy based on in situ CDI can be implemented in different imaging modalities with photons and electrons for low-dose imaging of radiation-sensitive materials and biological samples.