Laser COLOR limits data capacity?!?

Рет қаралды 88,372

Күн бұрын

What can a rainbow tell us about the limits of focusing a laser? Focusing a laser beam into a tiny spot is important in many technologies. In this video I will go through two examples: optical discs like CDs, DVDs and Blu-rays as well as laser engravers. Does the wavelength of the laser matter? Let's find out!
Thank you very much to Edwin En-Te Hwu and Anja Boisen for letting me use their illustration!
Link to their publication with even more, interesting info: pubs.acs.org/doi/10.1021/acss...
Edwin Hwu's channel: / edwinhwuhacks4science
Laser engraver Aufero Laser 1 and accessories donated by Ortur: www.aliexpress.com/item/10050...
Why does light bend? (Fermilab): • Why does light bend wh...
Why does light slow down (Fermilab): • Why does light slow do...
Calculate photon energy: www.omnicalculator.com/physic...
Calculate focus spot size: wavelength-oe.com/optical-cal...
Calculate depth of focus: wavelength-oe.com/optical-cal...
My Patreon-page: / brainiac75
Make your own laser beam dump: • Don't use strong laser...
My strongest laser, 5W laser vs. 5W LED: • Crazy difference betwe...
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#Laser #Rainbow #Brainiac75

Пікірлер: 203

@AliHSyed 2 жыл бұрын

crazy to think that when lasers were first invented, they were considered "a solution looking for a problem". Now they're the solution to pretty much every problem.

@jhonbus 2 жыл бұрын

Funny to compare to graphene, which since 1 millisecond after it was discovered, everybody's been saying it will revolutionise just about every aspect of science, but so far has remained steadfastly useless 😂

@ehsnils 2 жыл бұрын

Didn't they say the same thing about the telephone?

@Wourghk 2 жыл бұрын

@@ehsnils Depends on who "they" is. IBM said no one would ever need a personal computer, but only because they couldn't conceive of a way to monopolize and control it. Yet today, we slowly creep toward a world of cloud computing in an attempt to put the genie back in the bottle. Many ideas that seem ubiquitous are actually useless or even harmful, and many disused ideas could save the world. "They" will spread whatever technological rumors suit their agenda, just like graphene and green energy.

@ehsnils 2 жыл бұрын

@@Wourghk I thought it was Ken Olsen of Digital Equipment that stated that, but there have probably been many forms and assumptions that have ended up in the history of mispredictions.

@curtisoneill9929 2 жыл бұрын

I thought lasers were madeup by startrek and some weeb made it happen

@heavygaming1254 2 жыл бұрын

So that’s why Blu-Ray disks are called that! Fascinating.

@alexanderthomas2660 2 жыл бұрын

Funnily enough, the ray isn't blue, but violet. I guess “Vio-Ray” didn't sound as good as “Blu-Ray”… 😁

@dinitroacetylen 2 жыл бұрын

They are called blu-ray because they are powered by violet lasers. So obvious, really.

@theFLCLguy 2 жыл бұрын

The wavelength also plays a huge role in making computer chips, specially processors. They use light sensitive chemicals to make them and the smaller the features on the chip the smaller the wavelength must be. If I remember correctly currently they are using UV light and actually use multiple different masks to shrink the feature size further. They are running into the problem that the smaller the wavelength the higher the energy the light has and they can't use any smaller wavelengths of light without damaging the chips.

@Chriss120 2 жыл бұрын

the extreme uv light also makes it pretty much impossible to use lenses. mirrors are used instead.

@belg4mit 2 жыл бұрын

The bigger problem is that at the scale they're now working there are only dozens of atoms in a feature and quantum effects come into play where they are not desired, inhibiting they intended function i.e; tunneling resulting current leakage.

@thomascoolidge2161 2 жыл бұрын

@@belg4mit this is the real issue here.. with gates in the neighborhood of a few atom thickness quantum tunneling results in the leakage and the gates essentially impossible to “close”..

@TheSimoc Жыл бұрын

Yep. Actually the funniest thing is that with all that heavy struggle *and* success of making ever-increasingly performant computer chips, software industry has lost the once-had art of professionalism which would make things run with 10 to 1000 more performantly on existing chips. Meaning,90% to 99,9% of the software code - stored and ran - of "modern" mainstream software is purely unnecessary and useless code bloat, merely due to unprofessional coding.

@theFLCLguy Жыл бұрын

@@TheSimoc kinda true, you're kinda talking about RISC vs X86.

@SleepyMechanic 2 жыл бұрын

Before I watch I wanna test my knowledge. I remember when bluray discs came out, it was advertised that blue wavelength discs could hold more data because the focal point was smaller than a regular red laser dvd. Thus being able to make the data points narrower on the disc. Edit: I was taught well :D

@mme725 2 жыл бұрын

Dang, was pleasantly surprised at the precision engraver at the end. 1/5th the power and making like 2/3rds of the surface power density. It isn't the size of your wattage, but how you use it.

@nashsok 2 жыл бұрын

In addition to wavelength affecting how light is refracted, wavelength also is hugely important in how much light diffracts which is why even purely reflective optics will perform better at smaller wavelengths!

@fandyus4125 Жыл бұрын

Interesting, so what you're saying is that if I'm looking to design an imaging lens that is optimized for the UV-C region, I should look for a solution that uses only mirrors? I know that quartz and fluorite lenses are often used for this since they are some of the few materials that pass such short wavelengths well. I assume that a UV-C lens based on reflection only would be best made out of first surface reflection aluminium mirrors due to aluminium's high reflectance, even in UV-C.

@RaikouTch 2 жыл бұрын

I love that you added speckle to the blue laser in the focus depth animation. Nice touch!

@AkariInsko 2 жыл бұрын

@@Quickened1 think he’s talking about this 7:42

@Quickened1 2 жыл бұрын

@@AkariInsko ah yes, you are correct, he did say animation!

@Nobe_Oddy 2 жыл бұрын

I LOVE learning about about new things.... you have opened my eyes to SO MUCH that I never realized I had an interest in. THANK YOU! ....are you going to show us what that engraver is capable of doingt, and the differences between the 3 different lasers? I'm pretty sure you will, but I just want to remind you so you don't forget lol :) j/k

@DoctorOnkelap 2 жыл бұрын

Perhaps a comparison between an optical microscope and an electron microscope is useful. One cannot see things with an optical microscope if the object is smaller than the wavelength of the light falling on it.

@programagor 2 жыл бұрын

Excellent explanation! And that last scene with the rainbow, that was so intense. At first I noticed the Sun Dog and smiled to myself. Then I noticed the upper tangential arc without knowing what it is, and thought "hm, that's interesting". And then the upside down rainbow, and I lost my mind. And then you put the labels there!

@WilliamSteppan Жыл бұрын

Dr. Don at Fermilab is amazing! I love it when my favorite KZfaq personalities give props to each other ❤

@LuxGamer16 2 жыл бұрын

That is really interesting! Was looking for laser cutters, and this helped immensely with choosing what to get. Thanks!

@PerfectPilot 2 жыл бұрын

Brainiac 75 upload!!!! Yayyy

@brainiac75 2 жыл бұрын

Glad you like it, PerfectPilot. It was a LOT of work to make this video :)

@Hardcorelactation 2 жыл бұрын

@@brainiac75 we have been waiting for u. ur rlly close to 1mil

@PerfectPilot 2 жыл бұрын

@@brainiac75 :)))

@ComgrowOfficial 2 жыл бұрын

You got me! Love your channel!! Thanks so much for such an informative and comprehensive video!!!🥰🥰🥰

@tracybowling1156 2 жыл бұрын

I always learn so much from your channel!

@olivier2553 2 жыл бұрын

That's a very good summary video. It gives me about all the information I need to know.

@sulfie46 2 жыл бұрын

Amazing video! I had no Idea the wavelength/color of the beam influenced how we store information on optical media. Informative and professional video production as always!! just a shame i missed the early watch.

@Bianchi77 Жыл бұрын

Nice info, thank you for sharing it :)

@atdit 2 жыл бұрын

I love videos which teach me something interesting I didn't know before. Thanks!

@ronsku57 2 жыл бұрын

Again back when got my notification, (was late) came right into watching! Good video again!

@brainiac75 2 жыл бұрын

Not that late, Ronsku :) Thanks for the early watch!

@deiviuds 2 жыл бұрын

I've been enlightened by this video, thank you!!!

@kindwolf9949 2 жыл бұрын

Thank you for making this video.

@Surms41 2 жыл бұрын

Im going out and buying some crystals and glass to bend light now :) I forgotten how much I loved interacting with it, the rainbows!

@JustPyroYT 2 жыл бұрын

Very Cool and Interesting Video👍 your Videos are always the Highlight of the month :-) By the way: Your Voice is sooo relaxing. I like it 👍

@brainiac75 2 жыл бұрын

Thanks, JustPyro :D Doing the voiceover is the part of making the videos I like the least. I'll never get comfortable with speaking a foreign language into a microphone... But I know many of you appreciate the voiceover, so I will keep on making them!

@JustPyroYT 2 жыл бұрын

Yeah. Please keep making Videos 👍

@JoelMMcKinney 2 жыл бұрын

You speak English very well.

@izzieb 2 жыл бұрын

Harder to focus infrared you say? _Cries in infrared photography._

@brainiac75 2 жыл бұрын

Yep ;) CO2 lasers (infrared) typically have high power outputs, but they are hard to focus down to small spots. Still, I really need a CO2 laser in my collection... Thanks for the early watch, Izzie!

@fellipec 2 жыл бұрын

Very nice and informative video

@mix3k818 2 жыл бұрын

4:43 Brainiac75: "This is my second strongest laser. How about the other one?" KZfaq: *cuts to light themed ad* Me: Woah, are lasers that powerful?

@bazpearce9993 2 жыл бұрын

I bought a telescope with ED glass to help balance out the colour abberartion i had in my old cheaper scope. Works a treat.

@andrealaluze 2 жыл бұрын

I have the ortur laser and this helped me avoid losing more money and resources, thankyou

@shayhsopwagqehghggtfyggty2635 2 жыл бұрын

Nice videos brainiac75! (30 Mins) Love it!

@miragelee9754 2 жыл бұрын

Oh my god it’s been a while a while for me to come back to this channel… And oh my, this is a very good topic I want to think about so bad lol

@SockaWoW 2 жыл бұрын

Great video. ¨ That song at the very end urged me to play Civilization again.

@SoulDelSol 2 жыл бұрын

Great video

@jameskirk3210 Жыл бұрын

Hello, exce!!ent! A masterpiece of explanation, really well done with wonderfull schematics and comprehensive maths. Thanks a lot for your major contribution👍🖖👌

@MesutAtmaca 2 жыл бұрын

Thank you much 👏👏👏

@HelloKittyFanMan. 2 жыл бұрын

Yeah, that was a great video!

@chanheosican6636 Жыл бұрын

Well explained and the theories on why blue rays work better than CD and DVDS is well done (well explained).

@nigozeroichi2501 2 жыл бұрын

Nice, now I have to see what my engraver is that I just bought

@drakethedragon457 2 жыл бұрын

Great video! It was very interesting! lol

@xephanyoung8512 2 жыл бұрын

I like how even at the end of the video im still learning something new

@vitinhx794 Жыл бұрын

amazing bro

@lyrooo326 2 жыл бұрын

Awesome s new video to learn.

@JoelMMcKinney 2 жыл бұрын

So cool!

@JoelMMcKinney 2 жыл бұрын

Do you think Russia is shooting an unfocused laser at their enemies?

@Tarex_ 2 жыл бұрын

Seeing that focus spot makes understanding focal lengths so much easier, should probably build that beam dump and see if it works with a 40W (K40) CO2 laser to see the true focal point

@Sir_Uncle_Ned 2 жыл бұрын

It really is amazing just how much power a few watts worth of focussed light can really have.

@halonothing1 2 жыл бұрын

You didn't appear to put the link to the Fermilab video(s) in the description. Although I was JUST using the same photon energy calculator on Omnicalc the other day. I can't say enough how much I LOVE this site because it doesn't just do the calculation for you. It gives you the formula and explains the math, as well. Which is perfect because there's nothing I hate more than when somebody just tells me "this is how it works" without explaining why or how. By understanding the why and how of it, I can not only remember the idea a lot easier. But it makes a lot more sense. I'm not just memorizing some abstract idea. I'm actually UNDERSTANDING it intuitively. And that is the difference between actually knowing/learning something, and just remembering something. It's also why North American schools are horrible. All they do is tell you that initial idea without explaining how it works. Which infuriated me with math, because none of the concepts made any sense to me. Like most people, a lot of the math I learned just felt like some arbitrary BS somebody came up with for reasons. Because that's about as deep as the "how" and "why" of math goes until you get into post-secondary and you're taught by people who actually understand what they're teaching you and not just reading out of a book.

@18436Melissa Жыл бұрын

Everybody gangsta till your laser diode starts sounding like a jet engine. 💀💀💀

@Shogoeu 2 жыл бұрын

Light is amazing! We can do so many things with it.

@TheQwampa 2 жыл бұрын

Have you thought about making a video about pulse laser rust removal?

@brainiac75 2 жыл бұрын

Would love to, but don't have a laser powerful enough. May get one in the future ;) Thanks for the early watch!

@joebenjaminbrawley 2 жыл бұрын

As I was watching I was just curious do you happen to have a video on how that laser tester works and what kind of material it's made of and stuff like that? And if not would you be willing to make one?

@Outdoors2314 2 жыл бұрын

So cool

@victoramicci840 Жыл бұрын

You can still find those 1000w bulbs here in Brazil, they cost next to nothing, about 2 to 3 dollars... And with a advertised 2000h life

@corebuilder_youtuber8310 2 жыл бұрын

Amazing science.

@MrMegaPussyPlayer 2 жыл бұрын

0:50 And recently I've seen a YTber with a 100W (OUTPUT!*) laser array for projectors. What he got after focusing the several beams I only can describe as violent laser. *= Around 250W in, plus minus a little for cooling.

@vladthe_cat 2 жыл бұрын

I wonder how much data capacity an x-ray laser would have 🤔🤔🤔🤔🤔

@brainiac75 2 жыл бұрын

I think the way X-rays tend to go through or be absorbed in things (in stead of being reflected), would make the disc more expensive ;) UV-lasers are more realistic but I believe they would struggle with a lot of fluorescence in the discs. Thanks for watching!

@petermines3575 2 жыл бұрын

Cool.

@ast3r1xxx Жыл бұрын

perfect video..simple and understandable...thank you Brainiac 75!!

@usefulrandom1855 Жыл бұрын

What are you able to cut with these lasers?? In my job I installed/repair/train on laser cutters (amongst other things) pretty much the minimum is 30w although we do a 12w nobody buys it anymore. On the high end we go up to 150w but 40-100w are the most common. A 12w will cut 3mm mdf/ply/acrylic etc but its pretty slow, technically it can do a bit thicker but its painfully slow. I couldn't imagine how slow these are or are you only cutting like 0.5mm or card or something?

@SilverSpoon_ Жыл бұрын

yep, i would totally do my PC's backups on a 1TB CD-RW.

@Joe3D 2 жыл бұрын

0:22 All wavelengths travel at speed of light that's the other parameters which vary.

@sinpi314 2 жыл бұрын

Interesting

@jpt3640 2 жыл бұрын

Naaa, i don't think that it's because of shorter focal length. Its because of the wavelength... You cannot focus to a spot smaller than the wavelength. (Maybe times some constant factor) Uncertainty principle?

@Priyodarsono Жыл бұрын

The question that stuck in my head is why it's called Blu-ray when it's using a violet laser to operate...

@Napert Жыл бұрын

Is there something equivalent to a lens but for radio frequencies?

@WilburJaywright 2 жыл бұрын

TYG for rainbows!

@renatoetzi 2 жыл бұрын

Interesting. Still that leaves a question why CO2 laser cutters and CO2 medical lasers wich emit in the infrared are used for precision applications. Apart for the higher power output. Does that have to do with the beams shape?

@brainiac75 2 жыл бұрын

Visible light lasers will be more precise, but I think CO2 lasers are precise enough - and cheaper for high output. There may also be some other advantages of CO2 lasers when it comes to medical use, but I am no expert on medical lasers. Thanks for the early watch!

@Neobenedict 2 жыл бұрын

It is due to the material absorption, your skin/tissue/water is quite transparent to visible and near infrared, so you need a longer wavelength.

@clancywiggum3198 2 жыл бұрын

There's a few reasons: 1) high power output - maximum power you can get out of a typical visible light diode laser is on the order of a few watts, the cheapest CO2 lasers hit 40W easily. Fibre coupled diode lasers can hit high power levels as well but I believe they're more expensive and have worse beam quality. They also operate in infra red. 2) Material absorption - visible light lasers tend not to be absorbed consistently by anything that's not black, because by definition if it isn't black it reflects at least some visible light. Common targets for laser cutting include wood and acrylic sheets which absorb the 10 micron CO2 laser wavelength really easily while diode lasers just pass right through (you can cut red or black acrylic with a violet diode laser if you're very patient though). Steel and other metals absorb certain other infrared wavelengths really well, which is what high output fibre coupled lasers target. 3) Beam size isn't that big of a deal for cutting - CO2 lasers can achieve sub mm spot size easily but the kerf of a laser cut will often be substantially larger than this because it doesn't need to be sub mm - a 1mm kerf already outperformed any other cutting system other than EDM by leaps and bounds and it's super easy to compensate for. The absorption part is key for medical applications too - in fact a number of different types of lasers are used for different targets. CO2 lasers are used for certain skin procedures and iirc laser eye surgery, while tattoo removal uses near infrared and visible light wavelengths that are absorbed by the target tattoo ink far more than the skin they're blasting through. Certain highly specialised eye procedures use blue lasers that go straight through the eye and hit the retina in very precise areas to treat certain conditions as well

@jodystrickland9338 2 жыл бұрын

Your awesome

@HelloKittyFanMan. 2 жыл бұрын

"Now optical discs are being replaced by other technologies." Oh? Like what? As for archiving locally, which storage medium supposedly has longer shelf life and less cost per gigabyte than optical discs (especially single-layer Blu-ray)?

@bobwatkins1271 2 жыл бұрын

Could a red laser be used to read a BluRay disc if the distance between the laser and disc were increased to the focal length of the laser?

@acat.793 2 жыл бұрын

I feel like lasers are double edged swords. They can bring benefits to technology and exploration to an extent being incomprehensible. Lasers however, can be dangerous too if misused or mislabeled.

@aarongreenfield9038 2 жыл бұрын

One time a standard DVD player engineer Wondered what the big deal was, and asked a bluray engineer what the capacity was, and the bluray engineer said what's your point?

@maxifire32 11 ай бұрын

The next disk will use ultraviolet light and hold 30 GB of data

@TimChuma 2 жыл бұрын

CDs still have more robust error checking built in for some reason.

@glasslinger 2 жыл бұрын

You didn't mention the actual "fine details" that are possible with the two engraving lasers. How wide a line?

@brainiac75 2 жыл бұрын

You can see the line widths in the pictures, where I calculate the spot size. We are talking submillimeter. Like 0,15 mm when used correctly on the right materials. Thanks for watching!

@xBrokenMirror2010x 2 жыл бұрын

0:55 Isn't the question of "Does the wavelength of a Laser make a difference to the capacity of a disk?" have a very intuitive answer of yes? The Thinner the wavelength of light, the higher resolution the laser is, allowing you to store data in smaller and smaller individually readable parts on the disk. Although I suppose you could do it with a larger wavelength by taking the average data in an area while the disk is moving to interpolate the data structure, but that would cause a tremendous amount of overhead. But a Laser Larger then the data packets wouldn't be able to write the data, since it would write in a larger radius then the data.

@programagor 2 жыл бұрын

Deconvolution is still a problem that doesn't have a general solution. It helps to think of it from the frequency perspective, when you take the Fourier transform of the spatial data the two peaks blur into one.

@kevin42 2 жыл бұрын

With an added emphesis on "not in a vaccume"

@Kevin-jb2pv 2 жыл бұрын

Are there x-ray lasers? Couldn't an x-ray laser theoretically have ludicrous data density, or are we running into fundamental limits of optical technology in the UV range?

@doubledarefan 2 жыл бұрын

The first problem will probably be the laser simply passing through the medium, therefore, nothing could be read (or recorded, for that matter). Maybe by having the laser and the sensor on opposite sides of the disc, the sensor could register the slight variations between pits and lands. Which opens up another world of possibilities. Instead of binary, the pits would have varying depths, therefore varying degrees of transparency to X-rays, so if 8 levels of transparency are used, each pit (or pit-land/land-pit transition, if it is still done that way, which is the case with audio CDs), would be a byte, so 8x as much data could be stored, on top of the X-ray density possibility. This is still assuming it will be possible to record with X-rays in the first place. Ludicrous? I think we have entered Plaid territory.

@Clancydaenlightened 2 жыл бұрын

Some people need learn about what wavelengths are

@DerExperiminator 2 жыл бұрын

But why? Why is the cross section area at the focus point smaller with smaller wavelenght or focal length? Aren't the light rays crossing each other? An explanation for this, please. Thanks anyway for the nice video.

@xponen 2 жыл бұрын

the light ray refuse to converge because of a law of nature called "Heinsenberg Uncertainty" which states: if you know a particle's location you can't know it's momentum, and vice-versa if you know a particle's momentum you can't know it's location. Which is a weird and unexplained law of nature but at least we have a name of it for academic reference. So in the case of our laser light it has a fixed momentum because the energy of this light depend on it's wavelength (eg: bluish is more dangerous and energetic than red) and we already fixed its colour to a precise value so that mean its location (ie: the exact focus point) is simply not allowed to be known by the universe according to our Heinsenberg Uncertainty principle (ie: it just refuse to converge unless we change to different type of laser colour).

@DerExperiminator 2 жыл бұрын

@@xponen Thank You very much for Your reply and for the academic reference. Now i can read more about it. But already from looking at Your explanation, i do assume, that i will not understand it. I have to accept that i do not understand everything, and quantum physics is such a topic, so it seems :-) .

@reastle1307 2 жыл бұрын

WOW

@jojojorisjhjosef 2 жыл бұрын

For a sec there I thought u where gonna explain fiber optic data transmission and how one colour of light has less group velocity than the other.

@RainOrigami 2 жыл бұрын

honestly I think a prism or at least a diffraction gratings slide should be in every household

@FusionDeveloper 2 жыл бұрын

cool

@Kilgorio 2 жыл бұрын

Wow

@EpicLPer 2 жыл бұрын

👀👌

@nicolaiholst 2 жыл бұрын

Bliver klogere hver gang jeg ser en ny video 😀 pisse god forklaring... næste spørgsmål er om jeg husker det... haha 😀

@RicardoPenders 2 жыл бұрын

How can light slow down in glass and then speed up again when it leaves the glass?

@xponen 2 жыл бұрын

the how is; when light hit an electron (on an atom) the electron absorb the light energy and carry it across (the atom) as tho it had a momentum (known as "quasi-particle") then the electron decay after a set time and release back energy at the other end as the original light, this process repeat many many times because there's many many atom and overall process cause the propagation of light in glass to slow down. The photon is made of oscillating electric field (alternating positive & negative) that's why electron are the one which absorb it and release it again because if you recall a typical radio antenna circuit consist of oscillating electrons using capacitor & inductor to create & receive radio-waves.

@aetheralmeowstic2392 Жыл бұрын

I wonder...what would be the capacity of a disc that's read with a green laser?

@briananeuraysem3321 2 жыл бұрын

So this is why some of the PS2 disks I had were blue... huh

@MNanme1z4xs 2 жыл бұрын

HDDVD use green laser, about half to 2/3 capacity of blueray

@Jkauppa 2 жыл бұрын

paint on top of a (metallic) disc with ion beam, ionic deposition

@Jkauppa 2 жыл бұрын

ie, not electron cannon, but ion cannon, not crt but anode ray tube

@Povilaz 2 жыл бұрын

Wait what? I guess optical discs aren't as obsolete as I thought!

@polyblank73 2 жыл бұрын

How many tesla is your monster magnet? Have you already covered this?

@colin351 2 жыл бұрын

But why does a shorter focal length necessarily mean a tighter spot?

@bottlekruiser 2 жыл бұрын

It's very tricky to focus a wave to a spot much smaller than its wavelength.

@technoman9000 2 жыл бұрын

Hmm so there really is a limit to the density of optical storage... once you pass ultraviolet you just start destroying the media. Too bad, I was hoping to get terabyte gamma ray discs someday.