A STORM cycle
Stochastic reconstruction microscopy (STORM) is based on the fact that
individual points can be located using a microscope with much greater
precision than two points can be resolved. For example, if a sample
contains three fluorescent molecules that are too close together to be
resolved by a conventional microscope (a), they will produce a single
large image (b). STORM gets round this by switching off all of the
fluorophores with one laser, then switching one on at random (c) with a
very brief pulse of another laser. This fluorophore can then be accurately
located, and this information is stored by a computer. The process is
repeated until, several cycles later (d)–(f), all of the other fluorophores
have been located and a full image can be reconstructed (g).