The Fresnel lens was invented in France by Augustin-Jean Fresnel in the late 1700’s. He invented it as a way of magnifying light, allowing the light to be seen over much greater distances. While employed in France as the Commissioner of Lighthouses, the lens he invented came into popular use in lighthouses. Some form of the Fresnel lens is still in use today at some of the world’s lighthouses.
Now fast-forward to the 1900’s. You may not have been alive in the 1940’s or 1950’s, but if you were, you remember ads in the back of magazines, advertising a simple way to turn your tiny television screen into a giant viewing experience. These were simple magnifying lenses that you put in front of your tv for a slightly larger picture. Then in the 60’s someone figured out they could sell Fresnel lenses for this purpose. The Fresnel lenses were much cheaper to manufacture and were already being manufactured en masse for overhead projectors. Thousands of people bought these Fresnel lenses at $59.95 a pop under the brand name of Beamscope – quite a bit of money back then.
Ok, now we’re up to the 1970’s and the rear-projection television appears on the market. They used the same principles as the lenses described above, but they included the television and the lens in a tidy, but humongous, box. The Fresnel lens is there, though. Right at the front of the box.
You can’t really have a discussion about the Fresnel lens without mentioning Dan and Denise Rojas of GreenPowerScience. Check out his You-Tube channel and you can find out all the interesting science – and fun destructive things you can do with Fresnel lenses.