Fluorescent and confocal microscopies
The fluorescence microscope allows to detect the presence and localization of fluorescent molecules in the sample. The confocal microscope is a specific fluorescent microscope that allows obtaining 3D images of the sample with good resolution.
In these microscopies, the sample contains fluorescent molecules. These molecules are excited by a light beam and their fluorescence is then detected. In the confocal microscope, the excitation is focused on a specific point of the sample and then scanned in the whole volume. This allows to reconstruct a 3D image of the sample.
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A confocal microscope used to localize in-situ macromolecules.
(H. Raguet, Phototheque CNRS)