Thursday’s Thesaurus: Fresnel


Thursdays Thesaurus: Fresnel lens

Fresnel lens: (pronounced ‘Fre-nell’ sneaky French language and it’s silent letters) A type of lantern which produces an even, soft-edged beam of light through a Fresnel lens. The lens is a series of stepped concentric circles on the front and pebbled on the back and is named after its French inventor, Augustin Jean Fresnel (1788-18270).

When they are used in the theatre it is usually in a metal housing that also holds the reflector, a lamp assembly, and a Fresnel lens. Fresnel instruments usually have an easier way of changing the focal distance between the lamp and the lens. This makes them very flexible to use, and can create narrow and wide beams depending on what is required. The beam is very soft edged and is often used as a wash light for the stage.

Wait….what? another lighting post? Is that what you’re mumbling about? Ok look, I let someone else pick the term this week and they are a techie….so that’s what happened here, but don’t pretend it’s not interesting.

Ok look here’s a picture of it

and you should also know that these lenses are also used in lighthouses because they are so good at all that focusing……

And here’s the guy that invented it – doesn’t he look like he was a blast at parties?

Next week: PEPPER’s GHOST – (hint, it’s used a lot at Disneyland)

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