If objects around you begin to appear blurry and your eyes
have to strain to focus, a trip to the optometrist is in order. What do you
think the doctor would recommend? What else but another one of mankind’s best
inventions –lenses. A lens is an optical device that refracts light beams to
make them either converges. Lenses are typically made of glass or plastic. Then
there are lenses which don’t refract light. Instead they refract the non-visual
portion of electromagnetic spectrum, e.g. microwaves.
Lenses |
The lens is one of those rare inventions which derives its
name from an edible object-lentil. That’s because a double-convex lens is
lentil-shaped. The oldest know lens is a 3000-year-old rock crystal called
‘Nimrod Lens’ or Layard Lens’ deriving its name from the ancient city of
Nimrod, now part of Iraq.
One of the, most widespread uses of lenses is in aiding the
correction of human eye vision. Binoculars would be second in the list while
microphones and telescopes would be the most advanced and fancy
implementations. Lenses have gifted us with ability to see as far galaxies away
and as near as the tiny cells in our bodies. We owe a lot of useful discoveries
to their invention.