Super-resolution microscopy

Super-resolution microscopy is a form of light microscopy. Due to the diffraction of light, the resolution of conventional light microscopy is limited, as stated by Ernst Abbe in 1873. A good approximation of the resolution attainable is the full width at half maximum (FWHM) of the point spread function, and a precise widefield microscope with high numerical aperture and visible light usually reaches a resolution of ~250 nm.

Super-resolution techniques allow images to be taken with a higher resolution than the diffraction limit.

True subwavelength imaging techniques include those that utilize the Pendry Superlens and near field scanning optical microscopy, the 4Pi Microscope and structured illumination microscopy technologies like SIM and SMI. However, the majority of techniques of importance in biological imaging fall into the functional category.

There are two major groups of methods for functional super-resolution microscopy:

On October 8, 2014, the Nobel Prize in Chemistry was awarded to Eric Betzig, W.E. Moerner and Stefan Hell for "the development of super-resolved fluorescence microscopy," which brings "optical microscopy into the nanodimension".

In 1978, the first theoretical ideas had been developed to break the Abbe limit using a 4Pi Microscope as a confocal laser scanning fluorescence microscope where the light is focused ideally from all sides to a common focus that is used to scan the object by 'point-by-point' excitation combined with 'point-by-point' detection.

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