We demonstrate a novel active far-field wide-field label-free nano-imaging with high signal-to-noise ratio based on the nanoscale light source, pioneering in utilizing a combination of spatial frequency shift and Stokes frequency shift. Ring shape or polygonal shape nanoscale light sources emit photoluminescence and the light is coupled to a underneath subwavelength film waveguide to produce omnidirectional illuminating evanescent waves to shift high spatial frequencies for the far-field, label-free, 2D subdiffraction imaging. The photoluminescence of the nanostructure enables high-efficiency evanescent wave coupling in a large area for the low-noise wide-field imaging. The field of view is one order of magnitude improved from the previously reported far-field and full-field method. This approach’s versatility has been demonstrated by imaging integrated chips, Blu-ray DVDs, biological cells and various subwavelength 2D patterns. The configuration-----a special NW assisted slide-----is cost-effective, quite compatible with the standard microscope and can conveniently give super resolvability to conventional microscopy as a compact module. This work is significant for physics, materials, biology, chemistry, and other areas that need nanoscale visualization.
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