Visible Light Beams
From the side, a beam of light is only visible if part of the light is scattered by objects: tiny particles like dust, water droplets (mist, fog, rain), hail, snow, or smoke, or larger objects such as birds. If there are many objects in the light path, then it appears as a continuous beam, but if there are only a few objects, then the light is visible as a few individual bright points. In any case, this scattering of light from a beam, and the resultant visibility of a light beam from the side, is known as the Tyndall effect.
Read more about this topic: Light Beam
Famous quotes containing the words visible, light and/or beams:
“This visible world is wonderfully to be delighted in, and highly to be esteemed, because it is the theatre of God’s righteous Kingdom.”
—Thomas Traherne (1636–1674)
“Like the old soldier of the ballad, I now close my military career and just fade away, an old soldier who tried to do his duty as God gave him the light to see that duty. Goodbye.”
—Douglas MacArthur (1880–1964)
“The highway presents an interesting study of American roadside advertising. There are signs that turn like windmills; startling signs that resemble crashed airplanes; signs with glass lettering which blaze forth at night when automobile headlight beams strike them; flashing neon signs; signs painted with professional touch; signs crudely lettered and misspelled.... They extol the virtues of ice creams, shoe creams, cold creams;...”
—For the State of Florida, U.S. public relief program (1935-1943)