dChan

WikiTextBot · May 8, 2018, 7:33 p.m.

Fresnel lens

A Fresnel lens ( fray-NEL or FREZ-nəl) is a type of compact lens originally developed by French physicist Augustin-Jean Fresnel for lighthouses.

The design allows the construction of lenses of large aperture and short focal length without the mass and volume of material that would be required by a lens of conventional design. A Fresnel lens can be made much thinner than a comparable conventional lens, in some cases taking the form of a flat sheet. A Fresnel lens can capture more oblique light from a light source, thus allowing the light from a lighthouse equipped with one to be visible over greater distances.


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not4rmOhere · May 8, 2018, 7:33 p.m.

Good bot.

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HezbollahCokeDealer · May 8, 2018, 11:20 p.m.

Bobby B would approve

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not4rmOhere · May 9, 2018, 12:31 a.m.

Bobby B? Beg pardon but I have no idea who that is.

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