Lensless Imaging: OAM Sharpens the View

In OPN’s December “Optics in 2023” review of interesting research, a team from JILA, the University of Colorado, Boulder, and KMLabs Inc., USA, summarized an approach to lensless imaging of highly periodic structures, such as those used in nanoelectronic applications. The approach takes advantage of high-harmonic beams carrying orbital angular momentum (OAM), which generate diverse diffraction patterns. These patterns encode phase information that enhances the ability to computationally reconstruct the periodic pattern for superior detection of defects in periodic structures. This video shows diffraction patterns from highly periodic structures under Gaussian and OAM illuminations.