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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 the capture of images with a higher resolution than the diffraction limit. They fall into two broad categories: "true" super-resolution techniques, which capture information contained in evanescent waves, and "functional" super-resolution techniques, which use clever experimental techniques and known limitations on the matter being imaged to reconstruct a super-resolution image.〔 〕 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: # Deterministic super-resolution: The most commonly used emitters in biological microscopy, fluorophores, show a nonlinear response to excitation, and this nonlinear response can be exploited to enhance resolution. These methods include STED, GSD, RESOLFT and SSIM. # Stochastic super-resolution: The chemical complexity of many molecular light sources gives them a complex temporal behaviour, which can be used to make several close-by fluorophores emit light at separate times and thereby become resolvable in time. These methods include Super-resolution optical fluctuation imaging (SOFI) and all single-molecule localization methods (SMLM) such as SPDM, SPDMphymod, PALM, FPALM, STORM and dSTORM. On October 8th, 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". == History == 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. Some of the following information was gathered (with permission) from a chemistry blog's review of sub-diffraction microscopy techniques (Part I ) and (Part II ). For a review, see also reference.〔(WEM News and Views )〕 In 1986, the super-resolution optical microscope based on stimulated emission was patented by Okhonin.〔V.A. Okhonin, Method of investigating specimen microstructure, (Patent SU 1374922 ), priority date April 10, 1986, (Published on July 30, 1991 ), Soviet Patents Abstracts, Section EI, Week 9218, Derwent Publications Ltd., London, GB; Class S03, p. 4. Cited by patents (US 5394268 A ) (1993) and (US RE38307 E1 ) (1995). From the (English translation ): "The essence of the invention is as follows. Luminescence is excited in a sample placed in the field of several standing light waves, which cause luminescence quenching because of stimulated transitions...".〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Super-resolution microscopy」の詳細全文を読む スポンサード リンク
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