US Patent 6914250 Fluorometric detection using visible light

Systems, devices and methods of the present invention are for viewing a pattern of fluorophors capable of fluorescing when exposed to visible light, e.g., fluorescently stained DNA, protein or other biological material. The system includes a light source emitting light in the visible spectrum, such as a fluorescent lamp used in domestic lighting, a first optical filter capable of transmitting light from the source at wavelengths capable of exciting the fluorophors and of absorbing light of other wavelengths, and a second optical filter capable of blocking substantially all the light from the source not blocked by the first filter, so that the only light reaching the viewer is light produced by fluorescence of the fluorophors.