Abbreviation for Confocal Laser Scanning Microscopy. A method using an excitation laser focused into a narrow beam that traverses(scans) the field of view point by point. During excitation of the fluorophore, the emission is detected by detectors called PMTs(Photomultiplier tubes). The emission is reduced by a so-called pinhole, which is in a confocal plane with the plane of focus on the sample - thus the signal is detected only from the plane of focus and the possibility of optical sectioning arises.