Confocal Laser Scanning Microscopy
Laser scanning microscopy is an essential bio-imaging technique. A laser scanning microscope uses a laser scanner to scan through the sample by lighting many different spots sequentially with a laser beam and transform the reflected signals into an image. To obtain clearer images from biological samples, which have generally thick layers and lack good contrast, laser scanning microscopy adopts the confocal optical system together with fluorescent contrast agents.
The confocal optical system has a pinhole placed at the focal point that filters out unwanted signals emitted from the sample. As the pinhole allows the system to detect the fluorescence only from the sample's focal point, the optical resolution of the confocal microscope is far superior to that of a wide-field microscope.