Quote:
Moreover, as evidenced by the Woods Lamp, or black light technique (23), semen responds to illumination by longer wavelength frequencies of UV light (~ 350 nm) which is invisible to the human eye. When the substance is illuminated, it absorbs the energy and exhibits luminescence at a lower energy (longer wavelength) frequency of visible blue light.
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2) Long wavelength UV (350 nm) illumination of untreated dry semen produces a more narrow band of emissions centered near the blue visible region.
3) Illuminating dried semen with a band of visible (450 nm) light produces strong visible fluorescence in a broad region with a maximum around 520 nm (orange).
UV = ultraviolet