Through-Focus Scanning Optical Microscopy (TSOM) is an imaging method that produces nanometer-scale

three-dimensional Three-dimensional space (also: 3D space, 3-space or, rarely, tri-dimensional space) is a geometric setting in which three values (called ''parameters'') are required to determine the position of an element (i.e., point). This is the informa ...

measurement sensitivity using a conventional bright-field optical microscope. TSOM has been introduced and maintained by Ravikiran Attota at NIST. It was given an R&D 100 Award in 2010. In the TSOM method a target is scanned through the focus of an optical microscope, acquiring conventional optical images at different focal positions. The TSOM images are constructed using the through-focus optical images. A TSOM image is unique under given experimental conditions and is sensitive to changes in the dimensions of a target in a distinct way, which is very well applicable in

nanoscale The nanoscopic scale (or nanoscale) usually refers to structures with a length scale applicable to nanotechnology, usually cited as 1–100 nanometers (nm). A nanometer is a billionth of a meter. The nanoscopic scale is (roughly speaking) a lo ...

dimensional metrology. The TSOM method is alleged to have several nanometrology applications ranging from nanoparticles to through-silicon-vias (TSV). The National Institute of Standards and Technology, USA, produced a short on the TSOM method.

References

Microscopy {{optics-stub