The Insane Engineering of Fiber Optics Oct 22, 2026

Description

Why making glass fibers to send signals was almost impossible. Sponsored by Saily - 🌎 Get an exclusive 15% discount on Saily data plans! Download Saily app go to https://saily.com/veritasium Use code veritasium at checkout ⛵

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0:00 What are fiber optics?
2:02 Why Copper Phone Lines Had Limited Capacity
5:13 Trying To Go From Copper Communication To Glass
8:15 Why is glass so ‘lossy’?
11:29 Scattering and Absorption
16:00 How can you remove impurities in glass?
19:00 How They Make Fiber Optic Glass
26:47 The Technology that Made the Internet Possible

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Special thanks to the experts and collaborators who made this video possible:
Dr. Donald Keck
Prof. Vincent Chan
Sir David Payne
Dr. Nikola Alic
Jim Hayes
Jeff Hecht, whose book City of Light: The Story of Fiber Optics was an invaluable resource for this video (explore his work at https://www.jeffhecht.com).
Diffraction Limited, who made the fiber kits we used and some additional simulations that were critical to our understanding (https://www.youtube.com/@DiffractionLimited)
Trulala CANDY Chef (https://www.youtube.com/@TrulalaCANDYChef)
Additional thanks to:
ROSENDAHL NEXTROM for providing animations and fiber manufacturing 3D assets: (https://rosendahlnextrom.com/fiber/)
Bay Area Glass Institute for hosting our team. (https://bagi.org/)
Prysmian for giving us a guided tour of their fiber manufacturing plant, and our two on screen experts:
Sujeet Rao, Operational Excellence Fiber Director and Jon Fitz, Technical Sales Support Sr. Manager.

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References: https://ve42.co/FiberRefs

Note: The skin effect explanation is simplified. The full analysis involves the eddy currents' own magnetic fields, which induce further currents, and so on. Here’s an article on the same: https://ve42.co/SkinEffectDerivation

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Special thanks to our Patreon supporters:
Adam Foreman, Albert Wenger, Alex Porter, Alexander Tamas, André Powell, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Blake Byers, Bruce, Bryan Ackermann, Chris Brewer, Data Don, Dave Kircher, David Johnston, David Tseng, EJ Alexandra, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, Hayden Christensen, Hong Thai Le, Ibby Hadeed, Jeromy Johnson, Juan Benet, Kelcey Steele, Kyi, Lee Redden, Marinus Kuivenhoven, Mark Heising, Meekay, meg noah, Michael Krugman, Orlando Bassotto, Parsee Health, Patreon mp22, Paul Peijzel, Robson, Sam Lutfi, Shalva Bukia, Sinan Taifour, Steven, Sweet_Nemo, Tair Aurmont, Tj Steyn, Ubiquity Ventures, Vahe Andonians, wolfee

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Credits
Writers: Sulli Yost, Henry van Dyck
Producer and Director: Sulli Yost
Presenter: Henry van Dyck
Editors: George Reynolds, Trenton Oliver and Axel Oliver
Assistant Editor: James Stuart
Illustrators: Jakub Misiek, Raphael Aubry, Thomas Brizard and Emma Wright
Animators: Aleksandrs Loginovs, Alex Drakoulis, Andrew Neet, Andrew Wernette, Domonkos Józsa, Emma Wright, Fabio Albertelli, Rokas Viksraitis and Sulli Yost
Researchers: Aakash Singh Bagga, Sophia Rose, Callum Cuttle and Gabe Strong
Camera Operators: Sulli Yost, Aaron Zhizhin, Emilia Gyles and Jesse Chandler
Thumbnail Designers: Abdallah Rabah, Daniel Ellacott
Production Team: Anna Milkovic, Glen Griffiths, Jess Bishop-Laggett, Matthew Cavanagh
Executive Producers: Derek Muller, Emilia Gyles and Henry van Dyck