3D label-free super-resolution imaging

Abstract

Scanning white light interferometry (SWLI) is a label free optical 3D imaging modality with a vertical sensitivity of a few Angstroms (A). However, this optical far-field system, is laterally diffraction limited and resolves only a few hundred nanometers. We overcome this limit with microspheres that each produces a photonic nanojet. Thus sub- 100 nm features can laterally be resolved. To validate the performance of Photonic nanoJet based Interferometry (PJI) we compared it to techniques that provide sub-100 nm lateral resolution; Super-Resolution SWLI, atomic force microscope, and scanning electron microscope. We used a recordable Blu-ray disc as sample. Such a disc features a grooved surface topology with heights in the range of 20 nm and with distinguishable sub-100 nm lateral features that are unresolved by diffraction limited optics. We achieved agreement between all three measurement devices across lateral and vertical dimensions.