ฝัง
- เผยแพร่เมื่อ 8 มิ.ย. 2024
- The most important part of a lighthouse might be one of the beautiful tools hidden inside: the Fresnel lens, a breakthrough that changed seafaring and saved lives.
As the above video shows, these lenses satisfied a need for lighthouses that could shine farther and through dense layers of fog. The Fresnel lens, invented by Augustin-Jean Fresnel, helped do that by capturing all the light coming from a lamp, and then magnifying and directing it in one direction. Suddenly, lighthouses became more useful and shipwrecks diminished.
Even today, this breakthrough is still in operation. As the US Lighthouse Society reports, more than 75 Fresnel lenses are in use in American lighthouses, and businesses like Dan Spinella’s of Artworks Florida craft replicas that capture the beauty - and functionality - of the 19th-century breakthrough.
Watch the above video to learn how these lenses work and how they saved lives.
Further reading:
The United States Lighthouse Society’s history section is a great place to dig into the basics of lighthouse technology.
uslhs.org/history
Dan Spinella of Artworks Florida has a showcase of his fresnel reproductions, as well as useful videos about his process.
www.artworks-florida.com/
Barnegat Light Museum curator Reilly Sharp’s article about the Barnegat Lighthouse captures the stakes behind the shift from primitive Lewis lamps to the Fresnel breakthrough.
groups/barnegatlightmuseum
echoesoflbi.com/the-light-tha...
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"So how far is this going to shine?"
"Dunno mate. We need a bigger planet to test it on."
That’s incredible. What an amazing lens design, that the planet isn’t big enough to accurately measure how far it could throw light.
Or a taller lighthouse.
if they really wanted to measure it they could measure it from a plane or helicoptor
"We're gonna need a bigger boat."
You can measure the output and calculate the distance
7:03 "They rly don't know how far it could shine because of the curvature of the earth."
Flatearther left the chat.
Lol
omg I made the exact same comment before I saw this lol XD
I just typed the same/similar thing hahahaha
If you still believe that earth is round, you a real clown homie
@@jake42731 I don't get your joke???
This is the type of content I didn’t know I wanted to watch but found really interesting, That is what TH-cam is about.
Wrong. That is what TH-cam is supposed to be about but it's not.
@@brochal76 😭
That's what Vox is about and yes, it should be what TH-cam is about
Search great big story. It's worth it
No joke: I just got off the a video call with a staff scientist at Argonne National Labs, where we were talking about some details of the a Fresnel Zone Plates and their effects on their diffracted x-rays. We're using these to image materials on the 100's of nanometers. SUPER cool coincidence that this just went out today! Vox is the best!
Emh, coincidence or are mobile phones listening and feeding into Google? Check your permissions on your device? I know I found apps few active on my microphone that surprised me.
Yeah....St. Augustine lens was ruined with some kids' bullet and we had no lighthouse for quite awhile!!
Daaaaaaaaaang
Kids in america are illegal
*'MERICA*
@@roxxonsnowball8146 true
Why'd you spill your beans, Vox?
?
@@jazzysoggy12 It's called The Lighthouse, if you're into arthouse films you should see it. Absolute masterpiece
@@dorkle9085 oh
*yer
@Shrek Wazowski it’s not horror at all
fresnel lenses are also what most if not all vr headsets use, and that's why they have the little ripples when you don't have them on
Oh didnt know that thanks
Nice fact
In this case, it's kinda like a reverse fresnel, right?
@@rileywebb4178 i think fresnel just means that the lens is thinner than it should be because of that stepping design
Why?
Willem Dafoe was robbed of an Oscar
Brad Pitt was fun to watch in Once Upon a Time in Hollywood but his performance didn't seem Oscar-worthy to me. The most memorable acting he did was when he was on acid, but Willem just transformed for the entirety of The Lighthouse.
Also it's Willem, not William lol
That film needed subtitles in theaters but agree entirely
the scene where he was a dog omg
Did I just watch a video about Lighthouses?
no
No, you watched a video about the things that matter in life.
And I just liked it
I mean I watched a movie about one
Omg diD i jUsT wAtCh a vIdEo aBouT liGhtHouSes? Is this too complicated for you? Did you wanna watch the Teletubbies or some cheap Netflix reality show that’s more adequate to your understanding?
Wow..... I've been working for 8,5 years now on railways as maintenance guy, and I was always fascinated, how railway signal can be seen from huge distances using weak 12V lightbulb and you can clearly see when it is not seated correctly. Now I know why, because a type of Fresnel lense is used. You learn something every day.....
This lens is like something that you saw somewhere but just can’t remember
thats cause you've never seen anything like that before, but
me neither. closest thing I can think of seeing are some Christmas ornaments.
Well, most vehicle lights are frensnel reflectors. That's why you feel familiar.
Fingerprints
Old cars
Aputure?
I can't explain it, but there is something about Lighthouses that I love. I love the stories about an abandoned light house or an old lighthouse keeper who has been running it for decades. Its mysterious and kind of creepy at the same time
What Fresnel realized was that the work of a lens happens at the interface between air and glass. If you coud just collapse the curved surface to get rid of all that solid glass you could put a gigantic lens in a lighthouse. The beautiful curved prisms do just that at a fraction of the weight of a solid glass lens and you don't have to cast and grind an impossibly large and cumbersome piece of glass, let alone mount it at the top of a tower on a rotating clockwork.
I could see why he wanted to keep it all for himself at the end.
Yeah lol
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A̡̹̫͉̭̦̦̘̞͆͐̉̏̃̈͢a̴̻͖̞̟̺̼̺̺̟͒̉̓͒̕͢a̡̧̪̝̮̰̲̜̹̋̒̇̾̋͐̈͠͡a̶̛̝͙͍̮̯̲͊̿̀́̔̓̀̕͡á̴̡̖͕̬̃͊͂͛̀͢͡â̶͔̲͖̲̬̺̼͆̈́̀̕a̦͓̠̣̼̞̣̜̼̯͒͐̉͊̑̏̆̎á̢͖̳͍̜̳̦̑͑͒͂͆͊̓͞a̷̬̻̝̬̻͚̰̭̔̂̀̋͛̽̾̈́͝͝a̸̰̗̞̗͈̺͓̲̮͎̽̔̀͐͌ȁ͓͇̪̘͈̦̯͓̃̓̇̕͟ȁ̛̰̝͖͎̥̩͎͛̈́̽̕͠ͅạ̡̡̞͙̹̥̱̅́̔̾͝a̢̨͙͕̦̻̟̟̙͛͑̓͌̓̍͐̈́̃a̴͍̠͕͇̞͒̏̊̇̈̋̔͑͢ͅa̮̼͖̤̮͎̦̓̇̊͂̈́̊͢͠ͅa̧̮̥̬̦̭̔̿͒͐͐̒̃͘͢͡͝ͅa̸̧̙̟͇̭͍͓͕͋͗̀̀͒̑͠a̧̗͎̠̩͓̫͙̲͆̽͂̓̐͗͗̅̓͟͠ä̵̳̙̠̩͇̞́͌̑͒̌̊͡â̶̯͖̦̹̣͕̫͆̿́̏̓̒͌a̢̦̖̺̜͙̲͓͈͆͆̈́͘͠ͅȧ̗̱͙̙͔̪͈̯̩͌͊̓̿͗͆͡ͅa̢̡̛̛̙̤̦͎͇̮͈̟̅̈́̄̐̕a̼̖̮͎͈̭̍̓͆̓̿̕͞a̷̡̙̟͚͍̲͕͊̾͑͑́͟a̢̖̟̰̱̥̹̝͇̝͐̇̅̒͋͘͡ą̷̥̗͇̍͆̐̊́̂͢͝ͅą̩͈̯̱̰̫̂̄̎́͗́̽͞͡ą̸̢̡̘͇̰̘̜̻͔̉̊̈́̊͐a̘̘͈͙̣̽̀͐̋̈̅̀̋͘͠ͅą̶̢͖͔͖̭͙̃̆̆͊́͜͜ą̶̢̛̥͖̪͕͚̞͔̑͛̊̇̑̔͂͑͝ă̙̝̘̙͉̻̗̭̋̇͋́̒̇͢ͅą̴̡̗͎̠̤̏͒̏̌̾̊̎͛́͞ͅa̧̻̟̩͒̈̽̃̈̈̎̿͗͢͠ả̧̡̦̝̀̐̊́̏̇͡ͅǎ̴̜̙̲̺̫̹̩̍̏̎́̒͂̂͞ȁ͍̭͍̪̞̺͖̗̔̉̓̐́͝ą̴̨̤̭͙͒̇̏̾̒̈́a̷̢̗̭͇̳͕̙͔͈͈͋͐̐͋̋͊̾̕a̧̲̲̣͙̬̣͗̂͂̍̂̈͡h̴̢̪̭͎̗̲̺̖̜̐̇̒͋͂͊̀͝!̶̮̠̜̳̳̻̯͙͒̈̀̋͗ͅ
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He makes a lot of lenses. He has a channel that shows some of the manufacturing demonstrations.
@@NicoBabyman1 cool.
Every day, I find a job I never knew existed
Yer all fond of me lobster, ain't ye?!
Alright have it your way. I like your cooking
HAAAAAAARRRRRRKK!
To this day I’m baffled that neither Dafoe or Pattinson were nominated for an Oscar in The Lighthouse. Barnstorming performances. So neat to hear about the lens itself!
Man ‘The Lighthouse’ (2019) is such a genuine masterpiece
So thats what Thomas Howard found at the end of The Lighthouse
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Ḁ̢̗̞̗̻̙̼̹̀̊̃̆̆̃̒͘a̴̡̹̳͇̖̗̗̠͗̑̉̇̇͜͞a̬͓̜̦̦͍̎̒͋̇̆̈͌̚̕̚͢͜͜â̶̛̩̯͚̞̪̱͈̙̎͒́̔̚a̦̻̻̮̣̜̣͖͎͇͒͗̈́͆̄̊̏͊̂̚a̴̛̫̤̦̤̠̜͌̓̀̐̃á̸͓̺͙͙̹͙̂̒̄́͞a̢̢̧̖̣͋̆̍̅̏͐̌͋̂̐ǎ̸̢̝̘̻̲̞̈́̏̔̿̿̌̔̌͝a̡̳̤͕͙͚͚̠͎̺̅̂̓̋̑̅̒̅a̫̫̲͔͉̟̙̦͙͒̿͊̓̔͌̔̇͘͢ȧ̢̪͖̤̤̟̑͗͐̓͜ͅa̵̘͉͈̬͍͎͊͛̓͐͡ã̡͖̝̯̻̦̤̘͉͌̀͗͒̉̋͒͢͡ạ̧̺̜̜͍̻͓̜͂́̉̐͊͂͘ḁ̧̤̞͇̪̙̦̊̾̑͊̕͟͟ą̶̛͍͚̻̱̖̖̬̮̆̿̔͊̓̄a̡͚̣͔̜̾͒͗̊͠a͙͓̞̮̘̳͉̟̤̅̏̑̔̍̿̌͘͜a̛̼͎̘͎̗̔̽͊̌́̿̅͌͡ͅa̜̻̭͕̻̰̲͕̍̊̇̀̑̅̌̓̐̃a̴͖̩͖̭̳̮̟̼̱͑́̄̓̓̍̅͡ą̸̛̞͍̻̗͌͊̊̇̈̎̐͘͝a̶̡̪̺̠͙̾͛̋̎̋̓̕̕͘͟ͅa̝͍̤͓̩̍͛̍͌͛͟͠ą̵̧̼̫̙̳̑͌͛̉̕͜a̡̞͖͔̺̠̱̍͗̆̾͘̚͝ͅͅã̧͔͎̬̬͖͍͚̤̐̿́̔̚͘͝à̛͎̼̦̰̯̯͕̖̪̐̒͂͒̌͜a̛͉̣͕̥̝̮͍̠̭͈͒͐̎̈̂̓̿̈́͘ä̳̗̳͓̠̬́̅͑͒͟͝a̢͈̻̰̣̬͐͒̌̑̀̓͝ȃ̷̤̘̰̰͉̯̣̝͉̼̅̃̊͡ǎ̵̡̱̬̮̩͙̠̙͈̌̐́̀̊̔̾́̕͟a̼̯̲̝͉͉̙̖̟͇͛̽̿̆̓̕͞͠â̸̢̯̲̤̪̮̳͈͒́̂̕͢͝͠a̷͓͔̘̭̬͇͎̿̑̓͊́͋̂́́̓á̧̭̘̺̻͍͐̐̃̃͟͝a̴̻̗̫̹͎̎͛͌͊̇̆͟ḁ̡̜̻̅͑̄̔̋͘͢a͕̰̫̣͔͂͂͋͆̕a̼̦̹͍̠̋̇̍́̕ͅh̢͚͇͎͇̠͚̰̓̌̌͛̇̃̈̃͞͡!̵̡̡̳̣͈̟̣̳̭͑̇̒̿̎̽̚͟͡͡͞
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Your phone LED flash should already have a fresnel lens, so using another fresnel might be redundant
Good point!
Just realised :o
You can never have too many Fresnel lenses.
I think he was using the screen not the flashlight
If it was not for Augustin-Jean Fresnel we not have VR today we all thank you good sir and to all the lives you saved over the hundreds of years.
Why am I watching this, and where did my Interest in lighthouses come from.
Education
Fond of me lobster, aren't ye!?
A wonderfully told story as usual, Phil! So interesting to see where the origins of this technology - especially contrasted with the most common usage of fresnel lenses now - in TVs and screens to redirect the light toward the viewer! The amazing channel DIY Perks has several maker projects using fresnel lenses to recreate the effect of sunlight. But it makes complete sense that its original use was to redirect light in a straight beam for lighthouses.
I remember the St Augustine lighthouse from Buzzfeed Unsolved.
If you're reading this you have potential to create great things, you were put on this planet for greatness, remember that. Yes. You
Baby you light up my sea like nobody else. The way you guide the light makes me overwhelmed. But when you shine at the ground it ain't hard to tell, you don't know oh oh. You don't know you're a fresnel
I've gotta say, as a major lighthouse aficionado (my profile picture is in front of the Cape Henry Lights, for crying out loud!), I've never heard anyone refer to Barnegat as "The Graveyard of the Atlantic". That title is almost universally reserved for the Cape Hatteras National Seashore (better known as North Carolina's Outer Banks), where several first order Fresnel lenses were installed in 40 mile stretches. That region is rich in lighthouse history. For example, the old Cape Henry Light was the first federally funded public work produced by the original US congress. Cape Hatteras Lighthouse is the tallest lighthouse in the US and was actually lifted and moved about a mile in-shore back in 1999. All through the Civil War, the Confederates would actually take the Fresnel lenses out of towers when they came under risk of losing them to the encroaching Union Army. In the case of Bodie Island light, they removed the lenses and burned the tower down.
It’s funny, I was just thinking how many graveyards of the Atlantic can there be? I’ve been to the Outer Banks a bunch of times so I know that one of them..I used to live in Nova Scotia where Sable Island is known as that too (also with wild horses). And now I live near Cape Cod which of course claims to be the graveyard of the Atlantic
3:31 best name ever 👌🏼
You seemed to miss the whole point of Fresnel lens: they replace a conventional lens but much more compact and substantially less weight.
Thanks Vox for shedding light on this
This is something that we don't usually think about, but very interesting!
I'm 13, I have a test tomorrow, and I live in a landlocked country.
What am I doing here ?
Good luck
I live in an island nation, I actually can't imagine or conceptualise what living in a landlocked country is like. To have to travel through another country to get to the coast. Wild.
Good luck btw from which country are you from
I found this comment utterly hilarious
What are any of us doing here?
Love passing by the St. Augustine lighthouse every morning!! Awesome to see my backyard on youtube
I lived on Casanova...remember when it was dark when the lens was out for repair?
Woah! It's an honor yo watch this documentary.
"It was on either chariot wheels, ball bearings, or a mercury bath." I'm sorry, did you just say...mercury bath?
Yes mercury was used in a lot of early electronics too because it could transfer heat, or level things due to it's liquid nature.
Yes, a lot of things can float on mercury because it is so dense, and it cant really wear out like a wheel or bearing
Uhh, yeah. A ring shape trough filled with mercury. It's why there are so many stories about lighthouse keepers going mad, same as hatters; it's all just mercury poisoning
@@patrickmeyer2802
That sounds really fishy, since hatters didn't go mad - it was atters (i.e. snakes) who did, and then the word was corrupted. Lighthouse keepers had an inordinate amount of psychological issues because of the solitude imposed on them by the job.
@@Ildskalli Hatters did go mad because of mercury. They used to use mercury in making their hats, boiling the hats in the mercury to stabilize the wools in a process called felting, ultimately making them exposed to mercury vapors, and ended up having a mercury poisoning (which the symptoms include temperament changes and behavioral shifts), thus the name 'mad hatter disease'.
the light house is one of the best mind bending movies. its so greate
I was always fascinated by lighthouses. Thank you for the little piece of history, Vox!
Awesome that they brought up the lighthouse its an AWESOME movie
WHOA. I had no idea these were so beautiful!
I'm glad that you included how they spin at the end
This is why I like you Vox. I didn't know I wanted to learn about lighthouse stuff. I'm glad I clicked.
Part of my work is at the Point Reyes Lighthouse and this is one of the best, accessible explantations of Fresnel Lenses that I've come across. Kudos!
What a fantastic mini documentary. I am obsessed with light houses so I thank you very much for making this.
I still remember climbing up a ladder, fixing the Fresnel lights on our theatre and setting the light up. They are the most diverse set of light. When we did not have an extra spot, we narrowed down the fresnel and used it.
It is probably the one light we can do every drama in. And the application is basic and can be used in some advanced techniques too!
So beautiful and hypnotic to watch those lenses at work, true works of art and technology, and to think this was invented in the 1800’s. Amazing!
I literally got home now and tapped on TH-cam and found this.
wholesome
Wow imagine that
same actually, pulled an all nighter doing electrical work though
You need to look up how to use the word literally
I'm surprised this got 72 likes; it's such a random statement. Is it funny, because you're a sailor or something? 🤔
Can’t handle lighthouse lenses now thanks to The Lighthouse
Yeah lol everyone's talking about the movie only
Dan Spinella built that one too!
How fascinating, didn't expect myself to be so blown away by these fresnel lenses.
There is still a running fresnel lens on the lighthouse in my town. The old lens is on display too and its the 8.5 foot tall one
Now in the digital age, fresnel lenses are what make virtual reality headsets possible!
Cool
i didnt know
I'm happy that Fresnel lenses are getting more recognition !
thank you for bringing this man's work to our attention
Robert Eggers is a genius. Glad he found this guy
I can't wait for his next film the Northman
Eyyy, quick correction in here folks:
The biggest Fresnel lenses ever produced were actually the Hyperadient Lenses, with focal lengths of around 1330mm, compared to the 920mm of First Order lenses.
And i just realized the VR Lenses are flannels too woow
It's a Fresnel. A flannel is a type of fabric!
@@moniquecauley oh I see
Phil Edward's videos are what I live for :) loved the story!
I kept a light back in the late 70s. The Fresnel lens had just been replaced with a beam projector, and I regret that I never got to see it. I've since seen some Fresnel lights in service, and they are a work of art.
If I'm honest vox videos from the start of 2020 to date haven't given me the excitement they did before, also I wish the borders series would be brought back, I was torn that was cancelled.
Is it an odd coincidence I clicked on this video right after watching Internet Historian's video on the Costa Concordia?
i am SO the target audience for this video. i'm a huge fan of lighthouses and theatrical lighting and it just so happens that fresnels are pretty crucial for both. so glad that more people are finally learning about one of my very cool interests
Also used in projector televisions to improve efficiency of light sources.
Fascinating. Thank you so much! Sad the inventor had such a short life; who knows what he may have done. Mad skills, all of you!
as a professional photographer, I can tell you the a studio light with a fresnel lens is incredibly effective
Perfect video for my lunch break between study sessions! Beautiful lenses and interesting video!
"why'd ya spill yer beans?"
Don't forget the swedish invention that automatically turns off the lighthouse when it is day or the british one that doesn't just tell a ship where to stay away from but tells it where to go
"Don't forget the swedish invention that automatically turns off the lighthouse when it is day"
Sun valve.
Fascinating! Fresnel lenses have so many uses!
In France there’s a lighthouse that is so remote from the continent and seems to be built on a rock in the middle of nowhere that it took 14 years to build it (even though the war between France and Prussia delayed its construction).
That’s the Ar-Men lighthouse 🤗
I've never heard of this one before thanks! When i looked it up on google maps my jaw literally dropped when i saw how far offshore it was!
Thanks for the video. From Nova Scotia.
Currently making an animation about a light house. This was particularly timely!
This is the kind of stuff from Vox that I love. When they go so deep into random topics that I didn't know were so interesting
Mercury bearings too; they're awesome.
Ball bearings OR mercury floats.
Love this theme.
I live close to one of the biggest lighthouses in Europe so it's quite interesting.
Shoutout to St. Augustine! The oldest city in America and one of my personal favorites!
Great video! Being an NJ native and photographer I have some nice night shots of old Barney (as we call the Barnegat Lighthouse here in nj)
The diagram showing light spread with the lens was neat, especially with the explanation.
I love when Vox makes these cool videos about cool engineering.
Lighthouses are soo fascinating!
So I first learned about fresnel lenses because I wanted to retrofit my headlights and most manufacturers use fresnel lenses in there headlights to diffuse the light output!
Also The Lighthouse making an appearance was just icing on the cake. I didn’t realize how important of a prop the lighthouse was. I figured it was filmed at an old lighthouse not custom made!
His name is "Really Sharp"
makes sense
Great video
I've been in the Split Rock lighthouse on the shore of Lake Superior. MN side and it has all these features talked about. It is a true sight to take in.
Hey, a french invention, firstly used on a french light house, so lets talk about New Jersey.
And let's pronounce fresnel incorrectly
@@anthonyefarr they pronounce it correctly tho
@@hmmhmmmmmm Arrgh! I appear to be outnumbered by Americans & Francophones! :-)
@@anthonyefarr haha seems so, do people pronounce it otherwise in other countries?
@@anthonyefarr I was confused by their pronunciation as well. How does fres become fruh and nel become nal? Apparently its the American pronunciation but I've never heard it before.
8 seconds, woah I’ve never been this early😳 Hi Vox! Love from London
Boring
me too
@@luxembourgishempire2826 lol okay?
That's not what your boyfriends tells us ;P
Aeronaut loooool
Watching this at 4am thanks Vox
I didn't think I'd be interested in lighthouse lenses when I tapped the TH-cam alert for this video, but here we are.
Fascinating video. Peace!!!
The Lighthouse is one of the most masterful pieces of filmmaking since The Shining and it's a shame it wasn't nominated for anything
I feel so enlightened after watching this
This is something I never thought about but was always subconsciously curious about
Nice video.
This little guiding light of mine. I am going to let it shine. Let it shine. All the time. Let it shine.
Love the stuff you guys do. I'm from South Africa and I'm always looking forward to your content. I got a question, if you could answer for me, please... How did school (as we know it) begin? How did it develop through the years? Why do we study the specific subjects we take in schools around the world?
My grandma has a beach house in LBI where Barnegat Light is. I have gone up the light house usually several times every summer since i was a kid. I had no idea it was this important.
I never knew it would be fun to learn about a house on a beach
"Lewis Lamp: hey it's better then not having one" What an ad slogan lol
I grew up in Paignton, Devon. From my bedroom window I could see Berry Head Lighthouse. The lighthouse protecting ships & trawlers from the 200ft limestone cliffs of Berry Head near Brixham, just around the coast.
It was both the highest & the shortest lighthouse in the UK due to it being stop Berry Head.
I remember watching it's light sweep across my window. Two flashes then a pause, two flashes then a pause. Hypnotic, even that far away.
Growing up with a lighthouse you can see does make a connection with you. Comforting, even though you're only sailing a bed through the night.
Flash... Flash... wait... wait... wait... wait... wait... Flash... Flash... there it is...
I just realized, the flash on our phones use a Fresnel lens, impressive!
Hey, that's LBI! My family goes there every year. I've been up to the top of Barnegat Light a couple of times. Don't remember the Fresnel lens (not really sure if it's still in use) but I do remember having to walk up all those stairs. The observation deck is made of a steel mesh and enclosed by what is basically a chain-link fence, so if heights freak you out, it's kind of scary up there haha.
Intriguing video!
Unfortunately you missed the main point about fresnel lenses on why they were adopted.
They break up the refraction of light from one single heavy lens into smaller prisms.
Not only does this use less glass and therefore less heavy, it is also easier to manufacture (large optical elements need to cool very slowly to avoid cracks and deformations).
Additionally the light does travel through less glass there is less light absorbed in the lens, which makes it more efficient.
Some of the deployed designs also included mirrors for the outermost rays, which are inherently more efficient than transmissive lenses but engineers probably had not figured out how to manufacture those back in the day yet (look at modern telescopes, almost no transmissive designs are used anymore, also because there is no color diffraction).