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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
🌎 Get an exclusive 15% discount on Saily data plans! Download Saily app go to https://saily.com/veritasium Use code veritasium at checkout ⛵
Kao was already in Alzheimer’s condition when he received the Nobel prize, I remembered in an interview after the prize was announced, he could barely recall what optical fibre is. May he rest in peace and forever remembered
It's funny how we get frustrated when our internet takes a few seconds to load, without realizing that behind that connection are scientists who spent years solving a problem many believed was impossible.
I would love to see a video about submarine cables and fiber amplifiers!!!! thx
Back when I was in engineering school (1980-84), our professor pulled out a sample of what was supposed to replace copper for AT&T - circular wave guide. As he explained it, engineers had devoted their entire careers to developing it, run a test installation in Chicago, and saw it all cancelled when fiber optics proved, cheaper, easier to install and maintain, and had way more bandwidth. But it didn’t even exist when they started the project. Circular wave guide still exists for specialized applications, but it never became what it was supposed to because fiber optics did that job better.
We are proud to have helped to tell this incredible story! Thank you Veritasium, and we are also humbled to see so many curious and happy comments! And we agree - let’s now take a look under the sea with submarine cables and amplifiers! There’s so much hidden that makes our world come to life!
I worked in telecom for 43 years, I retired a little over a year ago. I remember going from analog to digital electrical cables, and then to digital fibre transmission. The bandwidth of fibre has yet to hit its limit. The limit is actually the switching speed of the electronics on either end of the fibre. They now use lasers of different "colours" or Lamdas, with prisms to separate the multiple beams that travel down a single fibre. The technology is amazing.
32:49 Ofcourse we want a video on the amplifiers. Who wouldn't want more of veritasium?
Narinder Singh Kapany was the father of fiber optics ENGINEERING wouldn’t have been possible without his contributions. Please do not forget these people.
Your whole documentary on who created the blue LED, how the blue LED was created, and why it was impossible to create is something that fascinates me the most. After watching that video, I thought that nothing is impossible. It just needs effort, determination, and pure love and passion for discovery, and it finally happens before our eyes.
My Dad worked for Raytheon as an engineer and in 1980 I went to visit him at work. They had one of the large fibre optic cables they were going to put in the ocean in the middle of the huge warehouse space. The end was open and all the fibres were splayed out, it was HUGE and then he asked them to turn off the lights. Then they turned on the cable....it was incredible. As an 11 year old science buff...wow....then we went to see Empire Strikes Back....what a time to be alive man,.
I am a fiber optic technician and my mind was blown when i figured out how its made, and then finding out about the underwater transatlantic fiber cables and how they lay them.... crazy.
32:48 yes please
I love seeing all the comments about the video contents 3 minutes after it was posted meaning they physically couldn't have watched it all yet.
It's crazy how it went from a theoretical/unsolvable problem, to a materials/plausible one, and finally into "just" a manufacturing/practical problem, from no one being interested to everyone racing to get there.
Uploaded 13 days ago and already on 13 million views is insane. 1 million viewers per day for nearly 2 weeks straight for a educational video about fibre optic cables is something I wasn’t expecting but that’s the beauty of YouTube!
guy at 30:00 100% saw they where doing a tour and came up to give a fun fact, you can tell he loves his work
The bit that really stuck with me is how the glass in a fiber has to be purer than almost anything else humans make — a light signal can travel for kilometers through it. It's surreal that the entire internet basically runs on photons bouncing around inside glass thinner than a human hair. The story of Kao being dismissed for betting on this idea makes the whole thing feel like a heist movie where the payoff was the modern world.
What I learned at a telecom company in the late 80s: 'One kilogram of glass replaces eleven tons of copper.' And that was when long-distance transmission through copper was already refined to the max, like using large diameter coax cables with air gap insulation to counter the skin effect at high frequencies while maintaining fairly high power levels.
I am amazed how Narender singh kapany is not part of this video.