Introduction to Fluorescence Microscopy

AbstractOwing to its chemical specificity, high brightness, live-cell compatibility and other favourable characteristics, fluorescence is ubiquitously used as a source of contrast in biological microscopy. Fluorescence microscopes are also indispensable for many fluorescence spectroscopy techniques, such as single-molecule spectroscopy, fluorescence fluctuation spectroscopy and any form of fluorescence (micro)spectroscopy performed in-situ in living cells and organisms. This makes fluorescence microscopy a key topic of this whole volume. This chapter aims at providing a general introduction to the topic, describing a generic fluorescence microscope and its essential components with more emphasis on objective lenses and their role in determining the resolution of microscopy images. The differences between widefield and confocal microscopes are explained and the later part of the chapter introduces briefly other variants of fluorescence microscopy and approaches to increase image resolution.KeywordsConfocal microscopyImage resolutionOptical microscopyOptical sectioningSuper-resolution imaging