Making the Invisible Visible
Ultraviolet is the name of a range of light (energy) having a wavelength shorter than the visible light detectible by the human eye. While ultraviolet is invisible, it causes many substances to fluoresce (glow) in a variety of colors that are visible to the human eye. The ability to make the invisible visible is what makes ultraviolet lamps so valuable for mineral prospecting, criminal investigation, postage stamp evaluation, and a host of other applications ranging from sanitation to medicine. The chart illustrates UV’s range of wavelengths in the electromagnetic spectrum.
CAUTION: Be very careful to limit exposure of your eyes to shortwave ultraviolet rays. These rays can “sunburn” the eyes and cause uncomfortable irritation. You should not look into a shortwave lamp when it is turned on. When working near a shortwave lamp
we recommend the wearing of protective glasses. Longwave ultraviolet normally does not irritate the eyes but we would not recommend staring into an ultraviolet lamp any more than we would recommend staring into any other light.