Fresnel lens
Lente de Fresnel
- Date
- 1819-1823 · confidence high
- Place
- Cordouan Lighthouse, France
- Credited to
- Augustin-Jean Fresnel
- Field
- Communication
What it is
Commissioned by the French lighthouse administration, Fresnel designs a stepped lens of prismatic segments that concentrates light into a far more intense beam using much less glass than a conventional lens.
The first prototype was tested in 1820 and installed at Cordouan Lighthouse on 25 July 1823, rendering earlier reflectors obsolete.
What it led to
- Worldwide replacement of lighthouse reflectors with Fresnel lenses
- Lighthouses visible from more than 30 km away
- Later use in spotlights, traffic signals and lightweight optics