Super-resolution imaging within reach
Although several optical techniques have been developed to overcome the resolution limit in microscopy, the optical imaging of subwavelength features is still a real challenge (difficulty to build, or risks of phototoxicity). Microsphere-assisted microscopy has recently made super-resolution imaging accessible to scientists. An easy-to-implement optical setup to perform full-field and contactless super-resolution measurements using transparent microspheres is presented. We show that this rather simple imaging system (in comparison with the usual optical nanoscopes) makes it possible to achieve a lateral resolution of 200 nm in air and, thus, to visualize nanostructured media and biological elements.