
Ask HN: How is the Eiffel tower blue light beam implemented? - roschdal
How is the Eiffel tower blue light beam implemented?<p>https:&#x2F;&#x2F;www.toureiffel.paris&#x2F;sites&#x2F;default&#x2F;files&#x2F;styles&#x2F;600x728&#x2F;public&#x2F;paragraphe&#x2F;image_texte&#x2F;img&#x2F;Tour%20Eiffel%20illumine%CC%81e%20depuis%20Champs%20de%20Mars%20%C2%A9%20E.Li%20%283%29_0.JPEG?itok=xpWQLb4V
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wnkrshm
Probably a collimating parabolic reflector with a high-luminance light source
(like Xenon arc lamps).

Edit: This article [0] says it's 6000W Xe lamps.

[0] [https://www.connexionfrance.com/French-news/Eiffel-Tower-
s-l...](https://www.connexionfrance.com/French-news/Eiffel-Tower-s-lighthouse-
beams-turned-off-for-repairs)

Edit 2:

I think the 'lighthouse' beam installation is made up of 4 collimated
searchlights [1] custom-made by Francis [2]. They've got close-up photos of
the Eiffel tower searchlights in their promotional material for their
architectural lighting.

[1] [https://www.wonders-of-the-world.net/Eiffel-
Tower/Lighting-o...](https://www.wonders-of-the-world.net/Eiffel-
Tower/Lighting-of-the-Eiffel-tower.php#Phare) [2]
[https://francis.co.uk/en_US/about-us/](https://francis.co.uk/en_US/about-us/)

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ermir
It's just a normal spotlight, it looks like a beam because the top of the
tower touches the cloud cover.

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touringa
The Luxor light in Las Vegas is similar, here's a walk-through!

[https://www.youtube.com/watch?v=lS2wFpHFoXA](https://www.youtube.com/watch?v=lS2wFpHFoXA)

