Microsphere-Assisted Microscopy: From 2D to 3D Super-Resolution Imaging

Here we present a new unlabelled far field optical imaging technique using microspheres to enhance the lateral resolution in optical microscopy. Both 2D and 3D super-resolution imaging using microspheres are considered, providing results of 2D and 3D imaging of surfaces with vastly improved lateral resolution and nanometric axial resolution for the 3D mode. Results are shown on narrow etched gratings in Si, nanotextured stainless steel surfaces and Ag nanodots.The main results demonstrate improvements of up to 3 times in lateral resolution, showing details of 300 nm for a microscope that would normally have a limit of 850 nm. Microsphere-assisted microscopy is a major new type of far field optical microscopy with great potential for high resolution imaging, characterisation and nanometrology in materials science and the biological sciences.