Motic Instruments Inc. Canada
October 06, 2006
3
The optical phenomenon that occurs when light absorbed by a material, creates a molecular
excitation that causes the material to re-emit light at a different wavelength.
Fluorescence Microscope for Epi-Fluorescence
The technique of fluorescence microscopy with epi-illuminators is based on the adaptation of
the vertical illuminator used in reflected light microscopy. The radiation emitted by the light
source first passes through the exciting filter and is incident to a short-pass filter* (dichroic beam
splitter). The radiation is then reflected into the objective, which also serves as a condenser.
The objective concentrates the exciting radiation in the object field. Fluorescent light emitted
from there is collected by the objective and returned in the opposite direction to the short-pass
filter, which directs it into the eyepiece through the barrier filter.
*
A filter designed to allow the passage of radiation of wavelengths shorter than a given limit.