Oh man, this was my phd thesis! - the simplest method to create a hologram is to just use 2D FFT. In far field, light amplitude and phase is just the Fourier transform of the aperture! - keeping the phase of the FFT result should get you a hologram already, but you need more optimization to get really good phase only hologram. - the conversion to black and white is basically binarizing your phase plate + adding DC value. The binarization creates phase ambiguity, that’s why you get two copies. - if you etch the pattern on glass via plasma etching, you get much brighter hologram. - the binarization is non-linear, so when I was working on this area the best way was to ‘error diffuse’ the phase using simulated annealing. It should be super fast these days to do that on GPU. I had a matlab code for that if you’re really interested. More than happy to share the phd thesis if you’re interested. I got super deep into this lol.
@SimonPinfold
Ай бұрын
Me watching the video: huh the phase holograms he's generating remind me of FFT. Comments: always has been
@SpeedcoreDancecore
Ай бұрын
I’d read your thesis if it was public
@simonjelley
Ай бұрын
I'd appreciate seeing your thesis too!
@AlexElsayed
Ай бұрын
Is your thesis "Free-space optical communications with retro-reflecting acquisition and turbulence compensation"? Searching your username found that on your scribd as "Thesis 11", and from there I found the PDF on Oxford's site via Google Scholar.
@tanvach
Ай бұрын
@@simonjelley See my response to @SpeedcoreDancecore :)
@AppliedScience
Ай бұрын
Your explanation of diffraction and image formation is the clearest I've ever heard. Very cool project and thanks for mentioning me.
@thethoughtemporium
Ай бұрын
Check out 10.1007/BF02935980 I was gonna include it, but the actual holograms worked better so it was cut for time. but it's pure dots and gratings. literally can be calculated in an excell spread sheet and drawn by hand if you were so inclined.
@franciscojavierramirezaren4722
Ай бұрын
AppliedScience, we are waiting for your next video! My favorites youtube channels together! Greetings!!
@Aanand-vi9nw
Ай бұрын
@@AppliedScience hey😯
@dominicwaghorn6459
Ай бұрын
85 dollars!
@TheZooloo10
Ай бұрын
@@dominicwaghorn6459scihub
@SimulatingPhysics
29 күн бұрын
Hi The Thought Emporium, I'm Rafael de la Fuente, the creator of diffractsim; I'm very glad you used diffractsim in this nice video! The discovery you have made is very interesting. There are also more specialized methods to make amplitude holograms with better quality. Do you want to have a talk, guide you, and we try to make them work? 🙂
@thethoughtemporium
29 күн бұрын
That would awesome! Please shoot me an email
@fractaltinker
Ай бұрын
Holograms are wild. As far as I know, this is the best way of making holograms that aren't just rapidly spinning fans, and I bet this would look SUPER cool. Congrats!
@collin6526
Ай бұрын
But a spinning fan wouldn't even be a hologram?
@fractaltinker
Ай бұрын
@@collin6526 yeah, and that's why I don't really consider them as such. It's just that it's the widely accepted method for creating "high-tech" stuff but the rapid LED spinning doesn't look that great.
@thorjohnson5237
Ай бұрын
LitiHolo made (and sold for a while) holographic film and a printer. They got flooded so are "film only" for a little while. The cool thing about their film is that it's self-developing and self-fixing. The bad thing is that it's... pricey.
@simonjelley
Ай бұрын
@@thorjohnson5237 I love litiholo, good to see them start producing again. The worst thing about the film being pricey is I tend to resist using it up quickly, and then its other challenge, a short shelf life) comes into play :(
@diegoiunou
Ай бұрын
there's a difference between volumetric display vs pov display vs hologram
@pox87
Ай бұрын
Quick suggestion (computer generated holography is pretty much my job). To go from a phase hologram to a intensity hologram, instead of linearly converting phase to grayscale, you should take the square of the cosine of the phase, it should work better.
@pox87
Ай бұрын
Also, there are ways to make the mirror image less noticeable (unfortunately it never goes away with intensity holograms). Too long for a comment, but feel free to contact me in case!
@atmel9077
7 күн бұрын
Square of the cosine or just cosine + DC-offset ? I would have thought that the square of the cosine will give you twice the spatial frequency.
@pox87
7 күн бұрын
@@atmel9077 Yes, sorry, i made a mistake. It's actually (cos(phi)+1)^2, else you double the spatial frequency, which is not that terrible, it just changes the size of the projected hologram. Anyway, the cosine of the phase plus one is the electric field of the interference with a reference wavefront (which you would be using to record an actual hologram on holographic paper, and should be equivalent to the light you shine on the printed one, so a flat wave), and then you take the square, which represents the intensity of light at the recorded hologram plane. The trick to make the ghost image less apparent would be to use something more complex than a flat wavefront as a reference, such as a converging or diverging one, and then add an appropriate lens in front of the laser you shine on the printed hologram.
@bitsurfer0101
3 күн бұрын
Is holographic projection possible/available at this point?
@pox87
3 күн бұрын
@@bitsurfer0101 Well, only if you REALLY lower your expectations. At the moment "holographic screens" are only about 1 cm wide, and have a viewing angle of only 20 degrees at best. Also, if you were to make a holographic videogame, you would measure the frame rate in frames per hour. This all makes them unusable as proper screens. They have a lot of cool applications, though, you can use them to manufacture stuff with lasers, and do some pretty cool tricks in microscopy experiments.
@flirkami
Ай бұрын
I am currently writing together my thesis on direct laser writing of phase change material based metasurfaces and I have to say you essentially did the same things I did just on a MUCH simpler and more affordable basis :D Of course the holograms I produced have better uniformity and such .. but I guess that is to be expected when comparing this to cutting edge research. It's increadible what you can achieve with this setup. The projects your are doing just absolutely AMAZING, especially considering the breadth of topics. Please never stop
@Fs3i
Ай бұрын
More simple and affordable affordable than an old film camera, a bit of developer, and a cheap laser pointer? Damn
@EpsilonRosePersonal
Ай бұрын
@@Fs3i I think they meant it the other way around.
@bread8176
Ай бұрын
Huygens Optics is a phenominal channel, always happy to hear him get a shout out
@Thaccus
Ай бұрын
That man is a legend.
@user-vg4zg9db3f
Ай бұрын
I am actually impressed of this video because Huygens Optics and NightHawkInLight (at 18:46) mentioned, my two favourite YT channels
@DakkyW
21 күн бұрын
For real, so many great minds here
@JohnDlugosz
Ай бұрын
<a href="#" class="seekto" data-time="415">6:55</a> What's shown is not an Argoscope. It's an eclipse maker. The pedals around the edge are designed to *inhibit* any such Argo effect and not throw any light into the center of the image!
@austinrimel7860
Ай бұрын
Good to know
@juhtahel7454
Ай бұрын
That's pretty neat. Do they bend the light away from the center geometrically or do they use that same bending to destructively interfere with the bent light that creates the argo point in the first place? (Or neither)
@-NGC-6302-
Ай бұрын
Yeah they look like concept sunshields for space telescopes. Saw a few when doing a research paper on the JWST. still cool eh
@simonjelley
Ай бұрын
@@juhtahel7454 Yes, they use destructive interference. To minimise diffraction you really want a gaussian opacity circlur shade that fades to see through at the edges, leading to a smooth non-peaky gaussian roll off for the diffraction pattern rather than the bright rings of the airy disc. Using just 100% opaque material this is approximated with petals, and the design of the petals has been optimised to cancel out with destructive interference at different scales as smoothly as possible.
@bbbnuy3945
Ай бұрын
also btw this sunshield is to block the incoming light of stars so the telescope can search for exoplants orbiting the blocked star and study those planets
@Waffles_Syrup
Ай бұрын
The coolest hologram I've ever seen was in the museum of illusions in pittsburgh; it was a hologram of a microscope, and you could walk up to it and actually look through the lens.
@vaakdemandante8772
Ай бұрын
wild
@njdotson
Ай бұрын
I've seen a video of that, I really want to know how that works
@davidestabrook5367
Ай бұрын
I saw that microscope hologram once at the Oregon Museum of Science and Industry (OMSI). It was really cool. Each time I went, I wanted to buy the "Astronaut Ice Cream", but it was too expensive. Finally I saved up enough money and bought some. It was a freeze dried slab of Neapolitan Ice cream, it tasted like dried foam, not much flavour, not very sweet, and I would not buy again. Real ice cream tastes so much better.
@styvensbelloge1703
Ай бұрын
I have seen an illusion with a telescope in wich you could look throuh when i was akid on a trip . i never succeeded in replicating it .Would be super interested by some materials on it
@makkyd123
Ай бұрын
This is actually a trick! in the first famous example, the hologram is generated using two different holograms merged during the process. So you are not actually looking down the microscope. But theoretically, it might be possible to make such a hologram with a magnified real image.
@okay-oliver
Ай бұрын
WHOA such little time between uploads! we're being treated frfr
@gavinjenkins899
Ай бұрын
"I have major resolution issues" meanwhile "There's no point in using the microfilm people suggested that's about 8x more linear resolution than Pan F is!" ... sigh. Keep in mind that you cannot get the resolution out of microfilm though with closed down apertures, you need like F/2 and just a lens that's quality enough to be pretty sharp at f/2
@mfbfreak
Ай бұрын
This! The CMS20 film should be able to get a resolution of about 500 line pairs per millimeter. I've used it for pictorial photography myself (not the intended use case but still awesome), it's absolutely amazing. I used Rodinal as a developer. The Adotech developer is meant for greyscale reproduction. If you don't get the hard black and white you want (the extreme contrast is another feature of this film!) you can try developing it in your other developer.
@hawland
Ай бұрын
<a href="#" class="seekto" data-time="410">6:50</a> I actually wrote a paper on this topic. Using a pair of axicons to transform the input beam into a very thin annular ring beam (with a diameter slightly larger than the diameter of the obstacle) will produce a higher intensity Arago spot than the traditional method of using a Gaussian beam. We showed it should also be possible to generate an Arago spot with an intensity higher than the intensity of the input source using an axicon and focal lens (under ideal conditions with a very precise setup). I can't speak about resolving an image using our setup, but it was an idea we had thought about trying.
@vaakdemandante8772
Ай бұрын
can you link to that paper somehow?
@hawland
Ай бұрын
The paper is called “Enlightening Arago-Poisson spot using structured light”, doi: 10.1364/AO.434435
@PeepingUkulele
Ай бұрын
I’m going to check that out. Thanks!
@Aceofspadeswt
23 күн бұрын
What software is being used at 4:26
@kimjongun8906
Ай бұрын
I just finished watching the gecko tape video wondering how far along this project was, what a wonderful surprise
@ianmcewan8851
Ай бұрын
I REALLY like where this series is going :) 1. The diffraction pattern and the image are related via a Fractional Fourier Transform, so you can get a better starting pattern using an invFrFT, though tuning the fraction can be a pain. I've never used RF's defractsim though - it looks amazing, so that's my weekend gone! 2. If/when you get to use a photon sieve transform on these, note that the oversizing on the holes effects the noise pattern in the whole image and so becomes another useful tunable parameter when trying to make a visually good image. (but is really annoying if you're trying to optimize for radiometry ) 3. When you get to thinking about the telescope, consider a Push Broom approach (with a modified mount) and the fun things that'll let you do if you happen to also have a diffraction grating around. again loving these vids!
@TylerDollarhide
Ай бұрын
The side comment about the bahtinov mask has helped tremendously. I'm an amateur astrophotographer and this information has has helped so much.
I love how this guy can just go from completely chill talking about some kind of mind-bending science, to whatever you call that in about half a second
@BiggyMalk
Ай бұрын
Bro i forgot dickbutt existed
@luislozano6929
29 күн бұрын
You have an awesome way of explaining things. You condensed 4 years of holography, wave propagation, and digital image processing courses into 20 minutes of practical applications.
@Dysiode
Ай бұрын
Epilepsy warning for these time ranges <a href="#" class="seekto" data-time="62">1:02</a> - <a href="#" class="seekto" data-time="69">1:09</a> <a href="#" class="seekto" data-time="150">2:30</a> - <a href="#" class="seekto" data-time="164">2:44</a> <a href="#" class="seekto" data-time="222">3:42</a> - <a href="#" class="seekto" data-time="276">4:36</a> <a href="#" class="seekto" data-time="289">4:49</a> - <a href="#" class="seekto" data-time="294">4:54</a> <a href="#" class="seekto" data-time="378">6:18</a> - <a href="#" class="seekto" data-time="383">6:23</a> <a href="#" class="seekto" data-time="423">7:03</a> - <a href="#" class="seekto" data-time="432">7:12</a> <a href="#" class="seekto" data-time="459">7:39</a> - <a href="#" class="seekto" data-time="471">7:51</a> even at 1080p Enhanced Bitrate the center of the detraction waves are flickering well above 3hz which is the typical baseline that justifies providing an epilepsy warning. I realize there's probably not much you can do now, but it would be extremely cool of you to provide in the future.
@ElectricNed
Ай бұрын
I don't need this, but I want the people who need it to have it. Thanks for providing it.
@mygirldarby
Ай бұрын
That's considerate of you. It is very rare for flashing lights to trigger a seizure, only about 3% of people with epilepsy show any increase in seizure activity due to flashing lights. So that means 97% are not affected. Still, for those 3%, I'm sure it is helpful.
@jameshughes3014
Ай бұрын
I appreciate it. I've got photosensitive epilepsy. This video wasn't a problem for me but, I'd really love it if this kind of warning was more common on anything with flashing lights. I don't know why youtube doesn't just scan the video and put a label on it. it would be a simple test I would think
@clownRatcity
29 күн бұрын
@@jameshughes3014too busy fighting the dreaded adblockers and ignoring everyone’s pleas to fix the bot issue unfortunately
@KallePihlajasaari
27 күн бұрын
@@jameshughes3014 It should be almost trivial to implement as it only has to be done once per video, each video gets trans-coded and scanned and what not a number of times as it gets saved into the archives and advert breaks are detrmined. I believe it is a specific range of frequencies that is the most triggering and this could be reduced to a number or even better the scenes could be played back at a different speed for those that have checked the "photosensitive epilepsy" checkbox on their profile.
@Jujukungfu
Ай бұрын
Those simulation animations are so freaking cool
@RobertMilesAI
Ай бұрын
It's probably been said but the bat signal is symmetrical so you could turn it 45 degrees and have the center line on the axis it's mirrored around, for a clean single bat signal
@eroraf8637
Ай бұрын
Fourier transforms are rotationally symmetric, not mirror symmetric. He either misspoke or misunderstood.
@asdfasdf-dd9lk
Ай бұрын
Hi, are you familiar with coherent diffraction imaging? What you're doing here is kind of a weird back-asswards version of that. If you let yourself stick to the specific case of Frauenhofer diffraction (far field), then the image:diffraction pattern relation is a Fourier transform (amplitudes not intensities), and there's *tonnes* of algorithms which can "solve" that for you, hybrid input output (Fienup 1986) is probably what would suit you best (likely the "fourier phase retrieval" you see in that python code uses a similar algorithm). Can send more information/advice/maybe whip up code that'll do what you want based off of my own if you'd like or don't want to dive into that particular kettle of fish, though it's really not super complicated when you get into it!
@NOTNOTJON
Ай бұрын
Yet another example of how useful fourier transformations are. Kind of like the science version of when you buy a new car, suddenly you notice that car everywhere you go. You should run with this idea to apply a fast fourier transformation but have the output constrained to a modified photon sieve rather than the fresnal lense approach. I'd love to see that actually.
@Hatasumi69
Ай бұрын
The video has just started, I but I saw your want to transfer holograms onto chocolate. I'm an artist researching the use of lasers to create structural colouration on sculpture surfaces and I'm currently looking at fiber lasers and seeing if they can possibly colour engrave silicone and then if it's possible to use the silicone as a mold to transfer the iridescent pattern. I feel like this fiber laser - silicone avenue may be of interest to you? Regardless, thank you for the endlessly fascinating and informative videos. You've been a major source of inspiration over the years. Anywho, back to watching!
@zuthalsoraniz6764
Ай бұрын
With JWST, the main part of the diffraction spikes is from the fact that the primary mirror is a hexagon made of smaller hexagons. Two of the spike pairs from the secondary mounting arms overlap with those from the primary mirror shape, while the third, from the "vertical" arm, creates the fainter, shorter pair of horizontal spikes.
@kendokaaa
Ай бұрын
When the first JWST images were released, some politicians and other people were complaining that for the billions of dollars it cost, there were these weird spikes ruining the images lmao
@danilooliveira6580
Ай бұрын
yes, I had the same confusion at the time because of the central smaller spike, I had no idea where it came from. after a while and talking with people that had the same confusion I finally figured out.
@yorgle
29 күн бұрын
I’ve been into holograms and learning about how they’re made since the late 80s in high school but now, thanks to your video, I finally have an understanding of how photo film based holograph generation works! Your channel was the quickest I’ve ever subscribed to!
@trinocerous
Ай бұрын
I searched the internet for months to get the same info you shared in the first 2 minutes of this video. You're the best! Thank you for sharing!
@joe2501echo
Ай бұрын
You're my favorite youtube scientist. Your experiments give me so many ideas for projects that might happen some time down the road.
@samk2407
Ай бұрын
<a href="#" class="seekto" data-time="760">12:40</a>, dude I watched his video on this phenomenon and I was enthralled. It's one of the most mind blowing things I've ever seen. I thought I understood diffraction, having taken college physics courses, but the lensing he demonstrated in that video was nothing short of astonishing. Like it makes total sense that it works, but it feels like magic. You make the special pattern and light bends to your whims like some kind of arcane spell.
@Heightren
Ай бұрын
Ok, so why don't we send this to NightHawk with his huge flashlight to make a batsignal on the sky now?
@_Jigen
Ай бұрын
We gettin' out of the collimated beam with this one bois
@LukeRiedler
Ай бұрын
This is absolutely my favorite KZitem channel
@zeekjones1
Ай бұрын
Before changing the pattern to greyscale try keeping only one color channel. The color version may be accounting for the chromatic aberration when drawing the pattern. My theory is a monochrome version doesn't need all of the color channels.
@danielpetka446
28 күн бұрын
the colors are not real, they represent phase. What he did is he turned phase into amplitude
@Darkknight512
Ай бұрын
Flipping a battery backwards in the middle of a big project is the perfect description of why jobs of an engineer or scientist often involve project time estimates that are reasonable, but every few projects, the estimate is wrong by 3-5x.
@frando2479
Ай бұрын
Nope, it's rather a perfect example why you should have SOPs and other QA measures.
@goldenegg1063
5 күн бұрын
Nope, this is a perfect example of what you shouldnt do, when you go climbing watermelon trees . You dont want to find that perfect big juicy ripe melon at the top of the tree . Only to Drop it because your camera battery was inserted backwards 🤷♂️🤦♂️
@JxBatterymanTTV
Ай бұрын
I finally commented and saw a video less than 5 hours after posting, Best channel for cool things ever!
@anonyme894
Ай бұрын
You can get an amplitude SLM from LCD projectors. Yet you'll also end up with a pattern convoluted to a grid (you may be willing to mask the others points thus). I already did two of those for teaching purpose, it's quite cool (since you can drive it with slides displayed on your laptop), yet you don't get phase control. If you want to try this, don't hesitate to ask questions!
@gfabasic32
Ай бұрын
I love this type of channel. And you mentioned Feynman. Win-Win!
@OhDeerJocelyn
Ай бұрын
I'm convinced that with enough funding, this channel would be able to create a time machine.
@gameygeemer4142
Ай бұрын
> Still trying to find an elegant method > Describes an extremely elegant solution
@YOEL_44
Ай бұрын
The Hacksmith actually did a great looking batsignal, might wanna take a look...
@rileynoname3529
Ай бұрын
This was so so so so cool- at first i was like “light projects cant be that exciting right?” But wow was i wrong. This was great!!
@mikeselectricstuff
Ай бұрын
For making castable holograms, I'd guess photolithography resists might be a way to go - either directly, or using them to acid-etch a substrate.
@charlizard_762
Ай бұрын
I actually manufacture the master stamps and actually a lot of the time just cut a diffractive grating into lenses and parts through diamond turning. It is very expensive and time intensive but the results are unmatched
@gownerjones
Ай бұрын
I freaking love this channel
@TheBMBass
14 күн бұрын
I just wanted to stop by and let you know that your videos encouraged me to go into synthetic biology. I used to watch you a lot during my undergrad studies and never thought I would have a chance to actually do similar work but landed a spot in a synbio lab for my honours and will be finishing my project up this year before going on to possibly do my PhD in the same lab. We are engineering fungi to produce antimicrobial peptides and it's some of the most rewarding shit, I never thought I would end up doing such awesome work and I wanted to thank you for keeping me inspired to do things that I thought would be impossible.
@rouletiquette
Ай бұрын
Holy balls, this whole series is rocking my nerd brain. I'm absolutely here for this.
@windcorpOLEGSHA
Ай бұрын
For anyone interested in observing an Arago spot, I've had great success using a DSLR camera without its lens, a laser pointer, reading glasses and a ball from a ball pen smashed between two transparent panes.
@jimmyzhao2673
2 күн бұрын
On Canadian currency, shine a laser (or pin point source of light, cell phone flashlight at a distance works) through the Maple Leaf, and it will project an image of the denomination.
@bitcharacter2824
Ай бұрын
I can't wait for this hologram chocolate project to turn into semiconductor fabrication
@thethoughtemporium
Ай бұрын
They were never different projects ;)
@mcb187
Ай бұрын
Buy a bunch of CMS II 20 now, EPM (the company that contracted Agfa to make it) went belly up about 2 years ago, and Addox has said they are running out of the film. I did send a message regarding where you can get other microfilm in bulk rolls if you need it, I hope that found you well.
@thorjohnson5237
Ай бұрын
Ooh... could you pass that along to me? I haven't been playing with film for a while, but... I can't afford a spatializer. Half of me wonders if I can can draw a hi-rez arbitrary pattern on a CDR...
@NoNameAtAll2
Ай бұрын
how does one send messages?
@djdrack4681
Ай бұрын
Try using a laser that pulses at high rate, AND rotate the laser (IE spin it). Pi is transcendent number, you're rotation won't be 100% centered and so the particles in laser beam will change angle + trajectory of how they're hitting the film, causing 2+ sets of defractive angles. This should help with resolution AND looking at the hologram from different angles (besides just straight on.
@smvwees
Ай бұрын
Wow! That contraption making each pixel output a different wavelength each time is awesome. That means you can make more natural colour images than with only RGB.
@lainalien
Ай бұрын
I used to have a laser pointer with a naked lady diffraction grating. very useful when camping as a teen.
@foxlanza
Ай бұрын
An ice cold Dr. Pepper and The Thought Emporium just made my day
@jimmyzhao2673
2 күн бұрын
One of the best holograms I've seen was that of a microscope, and you could actually look through the holographic microscope and see an image of what was on the microscope slide.
@whatitmeans
Күн бұрын
I designed grating holograms while doing my graduate thesis, and I can tell that there is nothing less intuitive that wave mechanics... if you think you got it, you are wrong. A few helps: 1) with your method you could do better than a frenel plate: if you got a lense and you cut it in "2pi-mod slices" you will got a flat lens that do makes image at focal poit, but if you change the curvature of the lens' slices by straight lines, you got a frenel lense, which makes focal point but cannot make image since has different focal points, now even worst, if you just make a binary pattern of those slices, you will have a frenel plate... since you could indeed do make grayscale patterns, for the telescope better try the first curved-slices such you could make a real flat lense (just a frenel plate with sinusoidal instead of binary pattern would work better, FP its the worst way) 2) also, you could design from the very beginning an aspherical lens instead of a classic parabolic or spherical one, it would reduce a bit the chromatic aberration (but the 2pi-mod is color dependent, so it will still be there) 3) looks like those holograms designed dot patterns instead of making "real images", but that could be also be done: the Fraunhoffer approximation tells you that the far field image is the fourier transform of the holographic mask... you could, in principle, to make modulated gratings (so you get twings images away from the central beam), modulated with you desired pattern on its phase (its too long to put eqns here, but you could find them in internet)
@lylechen8881
3 күн бұрын
I had a laser pointer 25 years ago. There were several caps with which it can produce graphics at the projection target. I was amazed for many years.
@michaelbiggs7987
25 күн бұрын
To turn an amplitude hologram to a phase hologram you need to bleach it with a potassium dichromate solution or other holographic bleach. You get better results if the film is overexposed. I played with computational holograms back when I had to use a PC XT for calculating (it took about 12 hours per point, so my holograms only had a few points). The results were printed on a LaserJet and photographed from across the room. Fun times! Looking forward to future updates.
@AllenKnutson
29 күн бұрын
What you call an "Arago spot" I knew as a "Poisson spot". Poisson predicted them and thought that they were so ridiculous, it disproved Fresnel's wave theory of light. Arago then decided to perform the experiment and sure enough, they exist, to Poisson's chagrin.
@danielpetka446
28 күн бұрын
<a href="#" class="seekto" data-time="1068">17:48</a> This is also a property of the 2D FFT. Every point corresponds to a sine wave and if you look at a 2D sine wave, it will look the same if you flip it around its axis. Mathematically speaking, the spectrum is always symmetric if the pattern is real and not complex, which is true, since you're just changing the amplitude and not the phase
@BariumCobaltNitrog3n
Ай бұрын
If Superfastmatt ever got excited, or happy, this is what he would sound like.
@NGC1433
Ай бұрын
Huygens Optics mentioned!!! So cool!!!
@danilooliveira6580
Ай бұрын
just a correction, and something I was also confused about at the time. the 6 diffraction spikes from JWST don't come from the arms, they come from the shape of the mirror. the diffraction spike from the arm is actually the smaller central 7th spike, the other 2 spikes from the other two arms are actually aligned with the shape of the mirror, so they overlap.
@dans-designs
Ай бұрын
😂 the irony, advertising for an ad free site... Love the video tho, fascinating stuff! Didn't want it to end!
@KallePihlajasaari
27 күн бұрын
There is that open source app that lets you follow your favorite creators across all video platforms. Grey jay developed with support from Futo and promoted by Louis Rossmann here on yt.
@ian-c.01
Ай бұрын
Wow, this just keeps getting better and better !
@vasyapupken
23 күн бұрын
<a href="#" class="seekto" data-time="626">10:26</a> - it's not about resolution ) Adox CMS is not a unique magical thing. it's just a technical film made for photocopy process (exactly what you are doing). such films have two features that make them work great as a mask: 1. their base are clearer than regular film and not scatter light too much. 2. their image are denser than image on regular negative. so when with regular "black and white" negative you actually get it more like "light gray and somewhat darker gray" with photocopy film instead yo will get something more like clear base and crisp black mask. also you can try Rollei RPX25 or Silberra U200
@elvendragonhammer5433
Ай бұрын
There's a team at MIT using a spatial light modulator & lasers to project a 3D hologram into a gelatinous cube of UV curable resin in order to create a full 3D resin print simultaneously with amazing detail resolution with no layer by layer printing- it does require post processing in that the beams converge creating a hardened shell of the object, & would then be cured to make the inside solid. I was thinking would also be very possible to drain / suction it out of the center if you just need something as a reference or something ornamental etc. You can also buy 3D printer bed plates usually coated with PEI that will allow whatever side is printed on the surface of the bed to leave an etched hologram into the surface. Your refined technique could be perfect for making custom ones, like for instance a hologram of a company logo, or The Thought Emporium...
@sammy5576
Ай бұрын
Canadian dollar notes have this built-in if you shine a laser through the clear part you get a projection
@kerzwhile
Ай бұрын
This is absolutely incredible!! 😮 brilliant work. ❤
@CNSFG
Ай бұрын
oh my god, amazing, i am currently working on my end school project where i want to show as many oldschool photography i can lear, actually i am only film shooter and i am trying older technique, but this? this is something else and perfect example about another art look
@sjoervanderploeg4340
24 күн бұрын
We used to develop photos as kids at a hobby club, I vaguely remember we also made holograms once or twice during summer!
@Lutefisk445
Ай бұрын
"Holo there, it's me, cristine, again!" Ifykyk. I, myself, am a great enjoyer of how light refracts off of tiny plastic flakes in nail polish- also known as a holo finish. Nail polish is one of my biggest hobbies, and holo is my favorite type of formula. edit: anyways, i forgot to finish making the point of my comment, but good video, light is cool!
@rattleheadx
Ай бұрын
Hey, I actually understood that reference! My wife is a long-time Holo Taco enjoyer...
@oneilgoisot9615
Ай бұрын
Bro I had a lot of trouble sleeping the timing is just perfect!
@VaradMahashabde
Ай бұрын
I think just the fourier transform of the image should work, as long as you pass through a lens afterwards. This is a standard technique of fourier optics. Although I think the lack of phase control necessitates an image doubling, since (in fourier optics speak), the one pulse at the center in x-space need a infinite spike pattern in k-space (so infinite diffraction grating gives a point), but translation by x of the point results in multiplication by a phase factor e^{ikx} (k is the wavelength in fourier space). The way to counteract this would be to have a second copy that is translated by -x, so the total phase factor is (e^(ikx) + e^{-ikx} = 2cos(kx)), which is real. Another option is to have the second copy by out of phase, so you can sin(kx) or any e^{i theta} cos(kx + theta/2) in general. This is ok because the phase is not varying, but a second copy is necessary. Maybe phase control can be achieved with some sort uv cure resin, which can be partially cured in places and then washed away? Then the varying heights of the resin (with it's different refractive index), can give static phase control, and this can overlaid on the mask which gives amplitude control.
@istvan.design
18 күн бұрын
Imagine making a hologram of an entire galaxy with everything perfectly sharp, you could zoom in to the grains of sand on Earth from hundreds of light years away.
@johnnicolls6810
Ай бұрын
I love this rabbit hole your going down
@AB-Prince
Ай бұрын
I think one simple change that may help is taking the grayscale image and using a threshold filter to make it pure black and white. as I would assume the gray parts of the image are causing the laser beam to scatter randomly.
@rulesofimgur
Ай бұрын
<a href="#" class="seekto" data-time="217">3:37</a> uh, no. I don't fully understand the math/science behind it but Scott manly did a good video on it. JWST has 8 spikes and 6 of them are from the shape of the mirror, 2 of the arms would cause this pattern where the the mirror shape already does that anyway(as far as I know you can't tell in images what ones they are) . The remaining arm (the top folding one) causes the 2 small spokes 180° apart at 30° to the main 6. I understand you're using it for illustrative purposes so this particular innaccuracy doesn't matter.
Instead of using a binarized (black/white) fresnel lens, consider using sin and cos like fresnel lens. "Hard" edges are inducing higher frequencies. So a grayscale image instead of a black and white print will give you an even better focus spot
@Erik_Swiger
Ай бұрын
You are seriously screwing with me as I make my dinner and watch this video. Please continue.
@tanvach
Ай бұрын
Thinking about why you don’t get good picture resolution at <a href="#" class="seekto" data-time="1163">19:23</a> is likely because of: - your grating resolution is not high enough. Ie you need more dense encoding in the grating to have higher fidelity images. - with higher resolution, you might want to add more offset to the grating so that you have less area near DC (or the optical axis). - the laser beam phase uniformity probably comes into play is not simulated in the software. The complex amplitude of your laser beam will convolve with the desired output, creating specking and broadening each pixel.
@MazeFrame
Ай бұрын
Another video, another stunning video!
@marcepanb
Ай бұрын
You can use lcd projector as spatial light modulator, but with half of the possible light phase shift compared to commercial SLMs. I done it and it works
@SnowcamoZ
17 күн бұрын
You can print these directly to a transparency with an ordinary laser printer... I did back in Ye Olden Days. The spatial resolution sucks, but that 'only' limits the angle of the diffraction. OK, the images were very, very narrow. But cool. Luckily our school logo was symmetrical around the origin, so It did not suffer from the negative diffraction orders. And naturally, you need to expand the laser in order to get any kind of resolution from such a coarse mask.
@jorgelotr3752
Ай бұрын
Fresnell lens are weird. Oldschool projectors used them, and if you looked at the lens directly with the projector off, there was an effect as if the reflection of outside light curved out of plane.
@0xTJ
Ай бұрын
This is awesome! It's so cool how "just" using film lets you make features that would normally be so hard to manufacture. Though I was expecting a shoutout for gratings that show the denomination through our money.
@SilntObsvr
Ай бұрын
Oh, *do* try the CMS20II -- I've used the original CMS20 (the II is a reformulation required by one of the ingredients in the original coming under an EU workplace safety ban). I've got negatives where 2000 ppi scans show individual rust grains on a piece of scaffolding -- with a normal 50 mm lens, hand held, from a distance of about five feet, and there's resolution left on the table (I've since gotten a better scanner and can beat that resolution by 3x, and still can't see individual silver grains in ISO 100 film, never mind microfilm-derived CMS20). In fact, CMS20II *may* have the resolution to produce *actual* computed holograms, not just those diffraction grating projections. *If* you have a lens with enough resolution, of course; CMS20II will beat most common lenses, but there are lenses for 35 mm SLR systems that can match or exceed even that film's native resolution. Oh, and I developed my CMS20 with coffee, vitamin C, and laundry soda. Adox's developer may or may not do better...
@tookitogo
10 күн бұрын
I wonder if you could use direct digital film exposure to get better results. For example, the imagesetters used to make films for prepress. They do 2540dpi, and the film is extremely high-density, so black is exceptionally black. And since these things are usually tabloid+ size, you could potentially make enormous diffraction gratings with them.
@theuser810
Ай бұрын
This youtuber is very smart. Good video!
@vortex_talon
Ай бұрын
videos like this is my i love this channel.
@Beregorn88
Ай бұрын
From my old course of diffraction optics, I would say your pattern should be the modulus (square root of the number times its complex conjugate) of the Fourier transform of the image you are trying to project. Edit: lot of people that did optics!
@Hobbychemiefreak
Ай бұрын
<a href="#" class="seekto" data-time="1063">17:43</a> it doesn't look like it's mirrored, but rotated by 180°. If it was mirrored, at <a href="#" class="seekto" data-time="1127">18:47</a> it would be possible to orient the bat symbol along the diagonal avoiding the double image since it's mirror symmetric, but it's not symmetric under rotation.
@Emre_Kermen
Ай бұрын
Whenever I see a new video by The Tought Emporium, I get super excited. Then I see it isn't about brains and get mad. Great content tho, even without brains.
@annakeye
Ай бұрын
The first hologram of this rainbow type I recall seeing was on the cover of a National Geographic magazine in the mid 1980s. It was a skull of an early human of some sort. I was so enamored with the image and whenever I saw it, I would pick it up and gently manipulate the position. I still love those holograms and I guess that's why I love Australian and Ethiopian opal for their holographic effects.
@DaedalusYoung
Ай бұрын
Hey, there's a film stock that was used to print sound on film. It's basically very high contrast, with very dark black. Might be a good stock to try for this purpose.
@wykpenguin
Ай бұрын
If Huygens rolled in his grave every time people messed up the pronunciation of his name, he'd be on fire due to friction.
@eeee69
27 күн бұрын
the brief animation at <a href="#" class="seekto" data-time="986">16:26</a> blew my mind, I had no idea there was a macroscopic model for refractive index (obviously it's not true 99%, hence my use of the word "model," but my intent should be clear.) Also, as was said elsewhere more elegantly, FFTs should be useful here, but I cannot say whether it will solve the symmetry issue.
@denispol79
28 күн бұрын
I think the majority of difraction pattern in JWST comes from the edges of every mirror segment. Of course the secondary mirror truss also contributes to the effect.
@BakeBakePi
Ай бұрын
That's so cool! I can't wait for your next videos exploring this more!
@julianoberhofer3550
Ай бұрын
<a href="#" class="seekto" data-time="208">3:28</a> The explanation for Hubble is correct, but for the JWST, the pattern is created by six diffraction spikes (lines) originating from the edges of the hexagonal mirrors and 2 spikes from the three secondary mirror supports. Two of these supportlines are hidden within the six "hexagon lines," while the last support generates the remaining two smaller lines. Matt Parker has an excellent video about this: kzitem.info/news/bejne/0Klmx2mXrpFkgKQ
@JosiGold1
Ай бұрын
<a href="#" class="seekto" data-time="577">9:37</a> The best use of a toonie
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