Fluorescence Microscopes

Fluorescence is phenomenon which can be used as a contrast-enhancement technique to view details in specimens which cannot be viewed by conventional means. An epi-fluorescence microscope uses episcopic (reflected) illumination and a series of filters to take advantage of fluorescent reactions in certain specimens. The first step is to initiate the reaction using a specific band of light referred to as the excitation band. This requires the use of a suitable light source and filter which project light at just the right wavelengths to excite the target molecules. After these molecules are excited, they eventually return to ground state and emit light at a lower energy-level. The emitted light is what would ultimately be observed.

Epi-fluorescence microscopes are available in upright and inverted forms, and include a variety of filter bocks for commonly used fluorochromes.