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Fresnel lens
This is what makes a lighthouse beam so powerful and concentrated. You have a ridged, "bullseye" lens in the center and curved glass prisms above and below it to produce the strongest possible light beam in every direction. The whole thing is mounted on a slowly rotating turntable.
From our article on how Fresnel lenses work.
Our images are published under a Creative Commons Licence (see opposite) and are free for noncommercial use. We also license our images for commercial use. Please contact us directly via our website for more details.
Fresnel lens
This is what makes a lighthouse beam so powerful and concentrated. You have a ridged, "bullseye" lens in the center and curved glass prisms above and below it to produce the strongest possible light beam in every direction. The whole thing is mounted on a slowly rotating turntable.
From our article on how Fresnel lenses work.
Our images are published under a Creative Commons Licence (see opposite) and are free for noncommercial use. We also license our images for commercial use. Please contact us directly via our website for more details.