Current Use
Large burning lens are sometimes made as Fresnel lenses, similar to lighthouse lenses, including for use in solar furnaces. Solar furnaces are used in industry to produce extremely high temperatures without the need for fuel or large supplies of electricity. They sometimes employ a large parabolic array of mirrors (some facilities are several stories high) to focus light to a high intensity.
The Olympic torch that is carried around the host country of the Olympic games is lit by means of a burning glass. The ceremony is organized at the site of ancient Olympia in Greece. The first use of this torch was for the 1936 Summer Olympics in Berlin.
Read more about this topic: Burning Glass
Famous quotes containing the word current:
“This is no argument against teaching manners to the young. On the contrary, it is a fine old tradition that ought to be resurrected from its current mothballs and put to work...In fact, children are much more comfortable when they know the guide rules for handling the social amenities. It’s no more fun for a child to be introduced to a strange adult and have no idea what to say or do than it is for a grownup to go to a formal dinner and have no idea what fork to use.”
—Leontine Young (20th century)
“Men perceive that equating love and domestic work is a trap. They fear that to get involved with housework would send them hurtling into the bottomless pit of self-sacrifice that is women’s current caring roles.”
—Debbie Taylor (20th century)