Microsphere-assistance in conventional, interference and confocal microscopy – modeling and experimental results

Topographical as well as microscopic imaging of nanoscale surfaces plays a pivotal role across various disciplines. Nevertheless, achieving fast, label-free, and accurate characterization of laterally expanded structures below the diffraction limit remains challenging. Recent studies highlight the use of microsphere assistance for resolution improvement. Confocal, conventional, and interference microscopy, augmented by microspheres, enable the imaging of small structures that were previously inaccessible. In this contribution, results of microsphere-assisted confocal and conventional bright-field microscopy (MAM) are compared to underline the decisive role of the confocal effect. Furthermore, an extensive comparison of simulated confocal results is presented to highlight the experimental results.