Overcoming the Optical Resolution Limit

When measuring with light, the lateral extent of the structures that can be resolved by an optical imaging system is fundamentally diffraction limited. Overcoming this limitation is a topic of great interest in recent research, and several approaches have been published in this area. In a recent study published in the Journal of Optical Microsystems, a team of researchers from the University of Kassel in Germany presented an approach that uses microspheres placed directly on the surface of the object to extend the limits of interferometric topography measurements for optical resolution of small structures.