Confocal microscopy

The confocal microscope scans a laser beam through a sample to excite molecules that are in focus. The molecules then emit photons, which are measured by a detector. A pinhole in front of the detector blocks out-of-focus light and hence improves image quality.

Confocal microscopy offers an improved resolution and signal-to-noise ratio over widefield. The ability to vary the height of the focal plane simultaneously while experimenting is also remarkably useful for 3D reconstruction of larger specimens. This method is more time-consuming than widefield in acquisition and image production and generally higher maintenance, in some cases there is also a tradeoff where some resolution is sacrificed to distinguish different structures in a given sample. Confocal Microscopy is an excellent method of optical imaging often preferred by researchers for applications involving visualization of genetic material or structural components of cells. It enables the assessment of the colocalization of structures and has had large ramifications in studies of the viability of cells.