Nanofocus

Nanofocus is a term used to describe the concentration of radiation, electrons, or other probes to a nanoscale spot, typically on the order of a few nanometers. In imaging and analysis, nanofocusing enables spatially localized interaction with a sample, improving resolution and enabling nanoscale measurements. The concept applies across multiple domains, including light optics, electron optics, and x-ray science, where the beam or light is focused to a nanometer-scale spot to examine or modify materials with high precision.

In electron microscopy, nanofocusing is achieved with aberration-corrected lenses and specialized optics in TEM and scanning TEM, producing beam diameters well below 10 nanometers and sometimes sub-nanometer probes. In optical systems, high numerical aperture objectives and near-field techniques push focus to the diffraction limit at the nanoscale. In x-ray science, nanofocused beams are produced by zone plates, Fresnel lenses, or compound refractive lenses, enabling nanoscale imaging, diffraction, and spectroscopy at synchrotrons and free-electron lasers.

Applications include materials science, semiconductor metrology, nanofabrication, and biological imaging, where localized probing is essential. Nanofocus methods underpin techniques such as nanobeam diffraction, high-resolution scanning, and 3D nanoscale profiling.

Some companies use the term as a brand name. For example, NanoFocus AG, a Swiss company that develops non-contact optical 3D surface measurement systems, markets instruments under the nanofocus brand, combining interferometric and confocal technologies for surface metrology. The term is also used in scientific literature to denote nanoscale beam spots in various modalities.