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] htt

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-lighthouse-beams-turned-off-for-repairs https://www.connexionfrance.com/French-news/Eiffel-Tower-s-l... 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-of-the-Eiffel-tower.php#Phare https://www.wonders-of-the-world.net/Eiffel-Tower/Lighting-o... [2] https://francis.co.uk/en_US/about-us/ https://francis.co.uk/en_US/about-us/