Fluorescent microscopy incorporates fluorochromes (fluorescent dyes) that are targeted to specific parts of an active biomolecular structure, such as a protein or an antibody. This conjugated substance is then excited with a narrow band of wavelengths of light. The conjugated substance, called a fluorescent probe absorbs this light and then emits lower energy, longer wavelengths of light. This process of excitation and emission allows the user to isolate and study specific substances within the specimen.
Modern Fluorescent microscopy systems use Episcopic Illumination (also called reflected or incident light illumination). Episcopic Illumination reflects the light onto the specimen by use of a beam splitting or dichroic mirror rather than transmitting the light through the specimen (Diascopic Illumination).
Usually full spectrum white light from a high intensity light source (mercury arc lamp, metal halide light source, halogen light source or LED) is transmitted through an excitation filter that blocks or absorbs all but the desired excitation wavelengths. This excitation radiation is then reflected through the microscope objective using a dichroic (two color) mirror designed to reflect the excitation radiation and transmit the emission radiation. The excitation radiation is focused on the specimen, absorbed by the fluorescent probe and then a longer, lower energy wavelength is emitted. This light then travels back through the objective, passes through the dichroic mirror and then is filtered by the emission filter to allow only the wavelengths of specific interest to the user to reach the eyepiece or camera.
Ludesco offers a wide range of fluorescent microscopes, including upright and inverted, fluorescent light sources, including mercury arc lamp, metal halide and LED. We also have available fluorescent filters and cubes for all applications.