High-Fidelity Far-Field Microscopy at λ/8 Resolution

The emergence of far-field super-resolution microscopy has rejuvenated the possibility for nanoscale imaging. Approaches to far-field super-resolution that utilize point scanning often depend on spatially reducing the size of the focused spot. However, the focused spot always achieves high resolution at the expense of extremely low light efficiency for the probing mainlobe and high-intensity sidelobes, which limits the applications in nanoscale imaging and might cause misinterpretation of samples. Here, a sharp probing spot is reported with the diffraction efficiency of 3.76% at the resolution of 38% of the Airy spot size assisted by the 2D multilevel diffractive optical element (DOE) experimentally. The diffraction efficiency of DOE is improved by at least two orders of magnitude at the same resolution by breaking the limitation of circular 0-pi binary structure superoscillatory lens. To eliminate the influence of the high-intensity sidelobes, high-fidelity images are reconstructed based on the modified deconvolution algorithm by virtue of the prior knowledge. Finally, high-fidelity far-field microscopy (HiFi-FM) is constructed and experimental results show that HiFi-FM allows the resolution of spatially complex samples better than 69 nm while acquiring high fidelity.

Automated summary

Far-field super-resolution microscopy has been made possible with the use of a 2D multilevel diffractive optical element (DOE) and a modified deconvolution algorithm, enabling high-resolution and high-fidelity imaging at the nanoscale.