ABSTRACT
Although SMLM, STED, and SIM are the most used approaches toward super-resolution imaging, other methods have also been developed. Albeit less broadly applied, each approach has its respective advantages (and disadvantages) and may be the method of choice for a specific application or in the case of instrument availability or budget restrictions. In this chapter we describe three approaches that have been reported in the past decade. We start with fluctuation-based imaging, a method that combines the switching on- and off of fluorophores and advanced image analysis approaches to improve the resolution of even very densely labeled samples in as little as 100 camera frames. We continue our discussion with image scanning microscopy, an extension of confocal microscopy that reaches a https://www.w3.org/1998/Math/MathML"> 2 https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003220688/bd4d4235-d90a-43ed-8c87-329986310e4e/content/eqni5_1.jpg" xmlns:xlink="https://www.w3.org/1999/xlink"/> increase in image resolution. We finish with near-field imaging techniques that exploit the strong confinement of light around the sharp tip of, for example, a cantilever in an atomic force microscope. By scanning the tip across a sample, it is used as a local nanometer-scale excitation source, routinely achieving resolutions of several tens of nanometers, even at near-infrared (micrometer) wavelengths.
