PRINTER FILES: I put the files on github. Download everything and read the README_and_HOWTO to file for instructions. Let me know how they work for you! github.com/electromagneticvideos/Laser-Printed-Diffraction-Grating

@esecallum

3 ай бұрын

or use the a cd / dvd as a ready made diffraction grating

@ElectromagneticVideos

3 ай бұрын

@@esecallum Yes - exactly!

@harshvardhan4771

2 ай бұрын

​@@esecallumwon't the act of shining a laser on the CDs or DVDs probably destroy it?

@esecallum

2 ай бұрын

@@harshvardhan4771 no. low power.. laser pointers ? heard of them? and you use blank dvd/cd

Not gonna lie, the manor of which you chose to describe the wavey nature of light ended up being more interesting then the fact one can use a office printer to do a sophisticated experiment. Very good explanation indeed :3

@ElectromagneticVideos

3 ай бұрын

Glad you liked the graphical explanation! I think viewers are actually split on what they liked or found useful - some the diy part,. some the explanation.

@gonnaenodaethat6198

3 ай бұрын

@@ElectromagneticVideos Even better :3 Reflects well on your methods.

@ElectromagneticVideos

3 ай бұрын

@@gonnaenodaethat6198 Thanks!

@harshvardhan4771

2 ай бұрын

​@@ElectromagneticVideosXD In my opinion, the viewership being split on which part they liked more, rather than whether they liked the video or not, is probably a win-win.

@ElectromagneticVideos

2 ай бұрын

@@harshvardhan4771 It is! Its always a struggle to figure out how much to put in a video and what to focus on. One thing I have learned is that the attention span on KZread is pretty low, so I am always careful what to include and easily over more than half of what I video gets edited out. This video worked well in the sense of the two well defined sections make it easy for people to skip they part they are not interested in.

As usual a fascinating video. Sending PCL direct to the printer, now that brings back memories. I was trained on Sharp laser printers, 9300/9600/9700 and later the 9400 etc. The PCU diags had a handy alternating lines option that would let you easily check the gears etc for wear and binding by making the variation in paper speed visible via interference patterns. A certain other large brand in the photocopier arena that also had a line of laser printers didn't have such a function in their machines so I write a file containing the PCL commands to produce the pattern on any printer. Tweak the resolution set commands in the file and it would work on more or less any machine. That simple file made it's way to several other of that brand's dealers and was used as a diagnostic for not only their laser printers, but also their photocopiers with printing capabilities. As Sutekh (Dr Who reference) said, "Interference! INTERFERENCE!"

@ElectromagneticVideos

3 ай бұрын

Funny - I don't remember Sharp laser printers. I do remember the early Brother ones which looked like a LaserJet II but mimicked a LaserJet I. Very neat that you wrote some PCL back then - clever idea to draw a pattern to make mechanical issues very apparent for diagnosis and must have been really satisfying to see your stuff in use like that! Dr Who's Sutekh - just googled Sutekh - odd that I don't remember because Tom Baker as the Doctor was in reruns when I was in university and we all watched it religiously! I still watch episodes of the new series when they appear.

This is the best kind of content! Calm and clear teacher showing how to do physics experiments at home for cheap.

@ElectromagneticVideos

3 ай бұрын

Thanks so much. Thats what I am aiming for!

Nice video. Two things. I have been teaching this for 30 years. We use TEM grids which are very cheap and accurate. Also, I took a screen shot from your video and pasted it into ImageJ. Set the scale using your tape measure. Drew a long rectangle across the 5 diffraction spots. Measured the profile (^K). Try it. You will like it. Also, gave up on acetate/transparencies 20 years ago (do many artifacts). Photographing paper and developing to slides at CVS gave good results. But TEM grids are still better.

@ElectromagneticVideos

3 ай бұрын

Thanks! TEM Grids - do you have recommended source? I did some googling and got a surprising number of results, some not that cheap! ImageJ - wow - never saw that before - just tried it - what a neat little application! Slides was my backup plan if I couldn't print fine enough with a laser printer. I really wanted a normal, everyday thing such a laser printed grating to emphasize that we don't really need anything "special" to do this. I was actually quite unsure if it was even possible with a transparency sheet and laser printer. Completely agree that it isn't the best grating, but was pleasantly surprised how well it worked in spite of its crudeness.

That was a really neat experiment. Amazing how accurate that was. Thanks for sharing!

@ElectromagneticVideos

3 ай бұрын

It was! I really didn't know if I could make a fine enough diffraction grating with a laser printer - I'm so pleased it worked that well. And yes - probably better accuracy than I deserved given how crude everything was.

Okay, printing a diffraction grating was definitely an idea I have never heard of before!

@ElectromagneticVideos

3 ай бұрын

Well I wasn't sure it would actually be possible - luckily it was with a bit of effort. I was surprised how well the rather crude diffraction grating worked.

How science was done in the renaissance period before lab equipment , brains and creativity. Well done.

@ElectromagneticVideos

3 ай бұрын

Yes! Its hard to imagine how the early scientists had to make do back then with limited resources. Even things as simple as insulated wire was not something you could pick up at the corner store. And here I am making do with nothing but a laser printer and laser pointer :)

@sparkyy0007

3 ай бұрын

@@ElectromagneticVideos Exactly right. Have you ever heard the story of the pencil ?

@ElectromagneticVideos

3 ай бұрын

@@sparkyy0007 No! Now you have me intrigued! So whats the pencil story?

@sparkyy0007

3 ай бұрын

@@ElectromagneticVideos Milton freedman. kzread.info/dash/bejne/aGuoqtapkcabp9Y.htmlsi=MwxVhb842LoZ1isX

@sparkyy0007

3 ай бұрын

@@ElectromagneticVideos Lookup M Friedman - pencil

This was very well presented (if a little slow) and actually gave me a much deeper understanding of diffraction gratings than school ever offered. Thank you for this.

@ElectromagneticVideos

3 ай бұрын

Glad I helped you with diffraction gratings - more coming on diffraction and light...

@MickHealey

3 ай бұрын

It's the right speed if, like me, you want to learn something. And I did, very informative and well presented.

@ElectromagneticVideos

3 ай бұрын

@@MickHealey Thanks for that comment - its always hard to know how fast or slow to go. With such a range of audiences on KZread, its hard to get things right for anyone. I was wondering I perhaps I had been too slow - maybe not! Nothing like getting some some feedback.form both you and the previous commenter.

@mookfaru835

3 ай бұрын

Teachers don’t teach.

@aeonikus1

3 ай бұрын

I watch it at x1.5 speed, it's great that way, understandable and quicker, ergo I can watch more content in my free time :)

Interesting and well presented. As an added bonus, voice level was calm and no spikes. Perfect for falling asleep while getting educated.

@ElectromagneticVideos

3 ай бұрын

Thanks! "Perfect for falling asleep while getting educated" - if I had included the math it could have been just like a real university lecture :)

amazing how you made your diffraction grating. thank you very much for sharing this idea. would be great to great the code. i will try this with my students soon. best wishes from overseas

@ElectromagneticVideos

3 ай бұрын

I have to admit, I wasn't sure if I would be able to make a fine enough one with a laser printer. I'm actually thrilled it worked - its somehow more satisfying than purchasing a ready made one. And a bit more real - we don't normally think of everyday things having diffraction effects (even though they do). Best wishes back to you from Canada!

@johanndohmann1281

3 ай бұрын

@@ElectromagneticVideos yes, it seems to be much more satisfying than buying things or using full equipped spectrometers. you made it. congratulation.

@ElectromagneticVideos

3 ай бұрын

@@johanndohmann1281 Thanks! So where are you "overseas"? I'm guessing Germany?

@johanndohmann1281

3 ай бұрын

@@ElectromagneticVideos yes. did you recognize a kind of German accent? i try to hide it ;-)

@ElectromagneticVideos

3 ай бұрын

@@johanndohmann1281 I guessed from your name and the fact that I get most views from the US, UK, Canada, and then Germany. I'm guessing because so many Germans speak English. It actually really pleases me - my mom came from Germany, my Opa lived in Bayern, and we lived in Bonn when I was a kid - dad was posted to the embassy there. And as a result Ich spreche Deutsch - although I'm way out of practice speaking it but understand it fluently enough to have subscribed to a number of German KZread channels. Grüße aus Kanada!

Thank you for the best lab experiments on the tube. ❤

@ElectromagneticVideos

3 ай бұрын

Wow- that high praise! Thank you very much!!!!!!!!

It's interesting to see this empirical experiment support the theory again. After many years of just being able to sanity-check the output of computer model(s) from having internalised these concepts, it's amazing how much detail I'd forgotten! This is a great educational video, I only have a single (hopefully) constructive criticism to make: orange to contrast with the red lines on a white background?? :)

@ElectromagneticVideos

3 ай бұрын

Yes - it is neat to confirm theory and things we take for granted, often without giving them a thought. To me the simplicity of this experiment also helps make it real rather than something hidden behind vast amounts of lab equipment. Your constructive criticism is very valid. Better choice of colors would have improved things. Animation showing the waves moving would also have been a significant improvement as well as superimposing a calculated interference pattern over the line drawing at various times.

About 1-2 decades ago, I used the trick of laser printing to transparancies to make PCBs using the photo process. I don't bother anymore and those sheets are hard to come by since no one uses overhead projectors now as well. I think it was cool to show making your own diffraction grating, but they are cheap and easy to come by if you just want to buy one. It would also be fun to try other lasers. Green and Blue are pretty easy to get.

@ElectromagneticVideos

3 ай бұрын

Wow - I did that to. And before that, sheets of high contract negative film from the local newspaper. I always found it was hard to get a consistent result across the length of the PCB. Usually one side was under developed and the other over developed. I presume it was because of non-uniform exposure from the photoflood I used to expose the PCBs photo resists. And to think these days$25 gets you 10x10cm plated though perfectly done boards in about a week or two! Yeah - diffraction gratings are east to get. I actually ordered a bunch in case the laser printing did not work. The reason I wanted to laser print one is to emphasize that diffraction is an everyday thing (ie nothing exotic) and that as tiny as the wavelength of light is, its actually pretty easy to measure with every day things. One other commenter mentioned mentioned how you could used an iron to transfer the black from a laser printed paper to something else. I havnt tried that yet but if transferring to something like glass is possible, that would eliminate the need for the increasingly less common laser printable transparency sheets (I'm not sure why they even sell them any more!).

Really cool experiment, monochromatic light sources can make for some pretty interesting effects. Such is the case for low pressure sodium lamps if you've ever seen or heard of them, not to be confused with high pressure sodium that was the dominant choice for street lighting and outdoor parking lots and security lighting from roughly the early 1970s to about 10 years ago when advancements in LED technology made LED a more suitable and sustainable alternative HID lamps. Because low pressure sodium lamps are a monochromatic yellow, with a CRI of 0,everything under a low pressure sodium light source appears as a yellow version of black and white, and this fact had severely limited their use and acceptance to very niche uses, notably astronomy observatories, even though their efficiency in lumens per watt was among the highest of all known electric light sources, 180 lumens/watt give or take.

@ElectromagneticVideos

3 ай бұрын

It does! Low pressure sodium - not sure I have ever knowingly seen one. I do remember as a student doing a rather uninspiring "find the wavelength of light" experiment that used some sort of gas discharge tube to create monochromatic light and then having to count interference fringes seen though two glass plates, ones sloping a certain amount relative to the other. I wonder if that might have been low pressure sodium. So what is the astronomical observatory use of low pressure sodium? Do they use a filter to block that wavelength from the sensors so it becomes a light source that doesn't interfere with telescope operation?

@Sparky-ww5re

3 ай бұрын

@@ElectromagneticVideos from what I understood, you are correct, though I've never personally been to one so don't quote me on that. Based on my research and talking to some friends that have been to an observatory, Flagstaff Arizona and Southern California near the Arizona boarder has the largest low pressure sodium lamp installation in the US, and Philips, the last known manufacturer of these lamps, discontinued them in late 2020 in part to very low demand. They were also used at beaches with sea turtle nesting areas, because supposedly the yellow light doesn't affect their habitat. Their approx. 180 lumen/watt and long life of around 18,000 hours would have made them the most common light source for commercial, industrial, street and security light, and likely delayed or prevented the adoption of LED altogether were it not for the very poor CRI of 0. Interestingly enough they were very popular in Europe for street lights until about 5 to 10 years ago when LED became the dominant choice.

@ElectromagneticVideos

3 ай бұрын

@@Sparky-ww5re Thats going to be so hard on the observatories. With the bad CRI limiting the application for such a lamp, its hard to imagine anyone investing in a suitable replacement - say a LED specifically developed to emit at that narrow band if thats even possible. I was wondering about a narrowband filter with some existing light source, but that would throw away so much of the light he efficiency would be dismal. Turtles - I know the issue well - had an Aunt who lived in Cocoa Beack, Fl. At certain times of year when I visited the curtains/blinds had to be drawn at night to prevent the light from messing up the turtles navigation. I dont recall seeing any low pressure sodium streetlights there - but maybe they had them in some places. Interesting that the Europeans used them for street lights in spite of the poor CRI. I presume energy saving was more important to them than for the rest of us.

@melody3741

3 ай бұрын

I thought Hps lamps were also monochrome????

@ElectromagneticVideos

3 ай бұрын

@@melody3741 Your comment intrigued me so just did a bit of googling: HPS en.m.wikipedia.org/wiki/File:High_Pressure_Sodium_Lamp_Spectrum.jpg and LPS en.m.wikipedia.org/wiki/File:Low-pressure_sodium_lamp_spectrum.svg Looks like HPS has a strong peak but a fair bit of energy spread out. LPS - look at that peak with almost nothing else in the spectrum. So I think while HPS has a restricted bandwidth, LPS is much more narrowband is almost single wavelength. I used to have a HPS lamp outside my garage door. It looked very monochrome. LPS must be so monochrome it almost looks unreal!

Ok this was absolutely fascinating, I love seeing constants derived from practical easily done experiments. Subbed and going to check out that speed of light video. Thanks for creating this!

@ElectromagneticVideos

3 ай бұрын

Glad you found it fascinating! To me, "constants derived from practical easily done experiments" really makes them more real. A wall full of lab equipment and displays really hides what is happening. Of course, not all experiments can be simplified to this extent. The speed of light one is equally simple, but does need an oscilloscope and a signal generator a $50 worth of laser and detector diodes. It is my favorite one though. Hope you enjoy it!

Great job. The physics behind were wellknown, but doing this with a 20 yr old laser printer for no money is awesome ☝️

@ElectromagneticVideos

3 ай бұрын

Thanks! What I am trying to do is show that some of these things (like wavelength of light) are much less removed form everyday reality than they may at first seem , and do it in a way that is understandable without a significant math or science background.

So this is a method of finding the wavelength of the cheap lasers on the internet. Very informative.

@ElectromagneticVideos

3 ай бұрын

You could certainly do that. But a finer grating would make it a lot easier.

Thank you for doing these videos! love to learn something new.

@ElectromagneticVideos

3 ай бұрын

Your welcome! I love doing the same thing - lots of great videos here on KZread! And more to come on my little channel!

First time here. Will probably be coming back. Great work.

@ElectromagneticVideos

3 ай бұрын

Thanks! Hope you do come back :) If you liked this video, you might also like the measure the speed of light video I did last summer: kzread.info/dash/bejne/lJd_xspwk6ypYLg.html

Energy is light and the absence of energy is dark (anti matter possibly) It's amazing that this reminds me of the phrase "let there be light"

@ElectromagneticVideos

3 ай бұрын

Actually the interesting things about anti-particles is they give off light/photos in the same way normal particles do - the photos are the same . I think there was a,n experiment at CERN to see if the wavelength given off by positrons in anti-hydrogen is the same as for regular hydrogen, or slightly off. Not sure what the outcome was ..

Wow, this is remarkable. Never knew it could be applied this simple. Maybe try using a high precision CNC with a laser module for better results. Excellent explanation on the subject.

@ElectromagneticVideos

3 ай бұрын

The simplicity is what I was going for - although it helps now that we all have "simple" lasers in all sorts of things! CNC with a laser - someone else suggested a laser engraver. I will have to look at those things and see if the required resolution is possible - how fine the bean is focused etc. There are certainly a lot of interesting possibilities if that would work.

This gets a like before I've even watched it because I know it's not clickbait and the algorithm needs to learn what I actually like. Added to my "watch later" list because I'll eant to watch it again. The printer content was enough for its own video :)

@khaitomretro

3 ай бұрын

I tried to do this with stuff I had at home in the 80s. Great to see someone succeed.

@ElectromagneticVideos

3 ай бұрын

I find at times I'm disappointment at what youtube picks for me. I'm not sure clicking like helps associate you with a video but it cant hurt. I find that if I dont get videos from a channel that I have subscribed to, clicking on that channel and watching a few seems to wake up the algorithm. No guarantees of course!

@ElectromagneticVideos

3 ай бұрын

Well I sure benefited from better resolution laser printers and lasers being commonplace. All our everyday stuff was exotic equipment back then!

Very cool. Nicely explained.

@ElectromagneticVideos

3 ай бұрын

Thanks!!!!

I remember almost the same experiment (except using a ready-made diffraction grating) from my school physics class, long enough ago to be using a He-Ne laser.

@ElectromagneticVideos

3 ай бұрын

It was way harder back then for sure. Although I say "with no lab equipment", the semiconductor laser, laser printer and computer used to do are there result of billions of $ or development. So really way fancier equipment than lab equipment in the "old days".

Really well explained. Thank you 😊

@ElectromagneticVideos

3 ай бұрын

Thank you - really appreciate your comment!

Excellent explanation!🎉

@ElectromagneticVideos

Ай бұрын

Thanks!

Very interesting and well explained! Thank you very much!

@ElectromagneticVideos

3 ай бұрын

Your welcome!!! Glad you found it interesting!

Loved this experiment and the result, amazing what science you can do without specialised equipment. I spent a LOT of time writing software to talk to HP and Epson printers years ago, when I ran a business and made my own invoicing software!

@ElectromagneticVideos

3 ай бұрын

Glad you liked my approach! I really felt doing it with everyday things helps make it a bit more real that with fancy equipment. Epson? The old MX-80 and FX-80 dot matrix printers by any chance? I messed around with them back in the DOS era - eventually managed to do grayscale images with dithering the pixels. It was so much harder to write sw back then without the development environments we have today. The amount of paper printouts we used to while writing sw would amaze people today. What did you use back then? I used Turbo/Borland for Pascal and then C which for a while really had a lock on the PC market. Even had CP/M Turbo Pascal for the Apple II that ran on a Z80 add-on card.

@Petertronic

3 ай бұрын

First printer was indeed an Epson RX-80. Then later was using an HP Laserjet 5N for many years, that thing was so reliable. I did all my programming in BBC BASIC(86) which is the DOS port of the BASIC from the BBC Computer - one of the best, elegant and most powerful implementations of BASIC in my opinon! One of my regrets is not learning C when I was younger, I stuck with BBC Basic for so long.@@ElectromagneticVideos

Trainee Physics technician here.. now with a greater understanding of just what the kids were going through with lasers and gratings. Cheers!

@ElectromagneticVideos

3 ай бұрын

Wonderful! It is a really simple but neat experiment - should be rewarding to help students get going. A related one is measuring the speed of light: kzread.info/dash/bejne/lJd_xspwk6ypYLg.html A bit more involved to do but still pretty simple!

WOW. Talking to the printer directly. I'm not surprised by that. Every time that we get a new copier/printer at work (architecture firm), it's a week of putzing with the drivers to get all of the line weights rights and shading correct. Thanks for the great video! DIY for the win!

@ElectromagneticVideos

3 ай бұрын

Its amazing that dealing with drivers for fancy printers is still such a pain! Glad you enjoyed the video!

@button-puncher

3 ай бұрын

@@ElectromagneticVideos Definitely! BTW, I wonder what the resolution is on those CNC laser engravers?

@ElectromagneticVideos

3 ай бұрын

@@button-puncher Gee - thats a really interesting thought! I dont know! I wonder if they could be used to heat and deform a plastic sheet which can make a great diffraction grating.

@button-puncher

3 ай бұрын

@@ElectromagneticVideos What if you painted a piece of glass, then had the laser remove the paint? Or painted a first surface mirror? Kind of the opposite of your laser printer idea. If anything, it's a reason to buy a new toy. ;)

@ElectromagneticVideos

3 ай бұрын

@@button-puncher Your right - somehow deposit a thin layer of dark something on the glass, and then vaporize it away. I like the mirror idea - a very think metal film, maybe oxidize it to make it darker to absorb the laser. "a reason to buy a new toy" this channel has been a great excuse to do just that or play with my old ""toys" that I normally wouldn't have time for. I will have to look at those engravers and see how fine a resolution the laser head can be moved to. It could be a great way to printer synthetically generated holograms. It will have to wait though - recently got a 3D printer and have to learn how to design 3D objects to print first.

Cool! Alternatively, you can do this with a couple razor blades and some very fine wire. You should know what the dimensions of the wire is and if it is standard off the shelf billing wire for instance for winding coils, you should know that. Or you can use your own hair, etc. you use the wire as a spacer for the two razor blades, and then project your laser into the defraction slit. Then I would take a picture of the diffraction pattern and put up a tape measure on the same frame, and then get a conversion from pixels to millimeters and then you can do the analysis at that point.

@ElectromagneticVideos

3 ай бұрын

I really like the idea of using wire or hair as a spacer for a slit. And certainly could calculate the wavelength from the diffraction pattern. Would be a bit harder to explain to viewers in as simple as possible way. But I'm thinking. You could carefully wind a bunch of wires next to each other around a form of some kind and use that to make diffraction grating assuming there are enough imperfections that light can leak though between the wires.

this is so obvious, why did i not use this before, its really useful, thank you

@ElectromagneticVideos

3 ай бұрын

Your welcome! Glad you find it useful!

Yet again, another thing i know nothing about . Still love the info.

@ElectromagneticVideos

3 ай бұрын

Glad you liked this video too! More to come!

Oh great, now you challenged me to make my own defraction grating. Lol i have a full shop of tools, from lasers to printers to 3d printers to cnc machines. Now i need to figure out the best resolution obtainable on each and make one. I aleays get side tracked with problems like these. Very cool video, im impressed you wrote directly to the printer. I have tried using some proprietary protocols and some can be quite challenging, others are very easy. Keep making awesome videos i love the inspiration

@ElectromagneticVideos

3 ай бұрын

Sounds like you have a lot of similar stuff as I do. I would be really interested to know if there are any common printers that can print finer lines than what I achieved. If you find one, let me know!. Yeah - those direct protocols can be tricky - took a while to debug! I'm really envious of your cnc machine. I recently got a 3D printer - that will have to be good enough for now. What do you use as a 3D cad program? More videos in the works. If you liked this one, take a look at the my "speed of light one" kzread.info/dash/bejne/lJd_xspwk6ypYLg.html If you redo and or improve on anything I did, let me know!

@newmonengineering

3 ай бұрын

@ElectromagneticVideos when I was in high school I used Autocad but today I use Fusion 360 and onshape for CAD. Both have a free version with some limitations. But both are very capable and once you learn them, you can make designs pretty quickly. It used to take hours to design something, now most things take me less than an hour. Many things like brackets or adapters only take 10 minutes. The hardest part is just learning how to do things in the beginning and wrapping your brain around certain concepts to produce the 3d object you want. The fastest machine I use is the laser, but the cnc is faster than the 3d printer for most things. Every project is different. Personally I enjoy programming and robotics. So these machines are all basically robots and I enjoy them in that aspect. I built my own 3d printer and my own cnc machine, and later upgraded them to off the shelf models.

@ElectromagneticVideos

3 ай бұрын

@@newmonengineering I just looked up Fusion 360 and onshape - interesting! Your lucky to have had Autocad in high school. I just missed it in university - had engineering graphics courses with pencil and a T-square - was of no use to me. Yeah - the learning curve - thats whats making be hesitate - one your get to know one your committed to it. Really neat that you built you own printers and CNC - amazing technology that we have access to these days!

Good job. Interesting it came out that close to laser wavelength.

@ElectromagneticVideos

3 ай бұрын

Thanks! Yes - more luck than anything given how crudely I took the measurements. Looking at the enlarged video clips it seems like the dot spacing on the wall was slightly greater than I thought when I did the experiment - so a bit more than the 10.5mm I had used. So that would have made the resulting wavelength a bit smaller - perhaps more in the middle or shorter end of the 530 to 570nm range.

- Let's make diffraction grating at home! Me: Oh, what a splendid idea! - All you need is a laser printer! Me: OOH, I HAVE THAT! - And then you have to make your own printer proto-driver! Me: Oooh. Yeah. Me (5 minutes later): you know what, that proto-driver alone is a good weekend project to investigate. And if I remember correctly, you could transfer laser prints onto glass with nothing more than a cloth iron.

@ElectromagneticVideos

3 ай бұрын

You know, I had forgotten that way of transferring laser prints. Glass would make a much better diffraction grating than the rather imperfect transparency sheet.

For diffraction grating use a CD or DVD and remove the label and you have a great Diffraction grating😊

@ElectromagneticVideos

2 ай бұрын

Were able to get light right through the CDs or DVDs that way? I only have writable ones and could only use the pattern in a reflective way. Just subscribed to you channel - you have a lot of interesting radio stuff!

Thank you very much! Printing worked well on an HP CP1515n at 600 dpi, on paper, but I don't have any transparent film on hand now 🤨 Must take one from my work tomorrow...

@ElectromagneticVideos

3 ай бұрын

Thanks for reporting your printer test. Just added it to the which printers work file!

Interesting. But now you've sent me down a rabbit hole. LOL I've spent the past hour looking up the details for programming my Brother laser printer (which DOES support HP/PCL), comparing escape codes and the like with the code you posted on Github.

@ElectromagneticVideos

3 ай бұрын

They not the first person who has accused me of sending them down a rabbit hole with the video lol! If you do try it and it works or not, please let me know and I will update the which printers work file. (or update it yourself - it should be publicly update . If it doesn't work, and you fix the code for that printer, it would be great to make that available too!

super duper scientific ..... i wonder if you could make a video on a more primitive method on finding light frequency

@ElectromagneticVideos

3 ай бұрын

Given the enormously high frequency of light, I dont think there is a simple way to directly find it. But, if you have the wavelength λ and the propagation speed c, frequency f = c/λ. And with that in mind, look at my video showing simple way to measure the speed of light kzread.info/dash/bejne/lJd_xspwk6ypYLg.html So, from that video you have c, and from this video you have λ. Put it in the equation and you will get f!

video was just awsome

@ElectromagneticVideos

3 ай бұрын

Thanks!

Mate! if you're ever in Melbourne (Australia), I'd like to buy you a beer...

@ElectromagneticVideos

3 ай бұрын

Well thank you! I will look forward to it :) Actually I visited you wonderful country about 15 years ago. Never made it to Melbourne unfortunately - rented a camper van (that's caravan in Australian) and drove up the east coast from Sydney and then back down along the edge of the outback over a period of 2 months. Amazing trip - and I do want to visit again sometime and explore elsewhere.

Fascinating physics. Love it. I was curious what the results would be when you said you were going to measure the wavelength of light. As light covers a HUGE range of frequencies, it makes sense you would get 660 or 670 nm. That's in the range of red light fairly close to the IR spectrum. It would be interesting to see how this works with a green or blue laser diode.

@ElectromagneticVideos

3 ай бұрын

Thanks! I suppose I should have said red laser diode light :) I just looked up the "visible spectrum" of light which is apparently about 380 to 750nm depending on the person so almost a 2 to 1 range of wavelength. If you rearrange the simple equation I did towards the end of the video, you can see that as the light wavelength gets shorter, the space between the dots that I measured will decrease proportional to the decrease in wavelength. The green laser I used in the "Speed of Light" video was 520 nm. Not sure how typical that is for green semiconductor lasers. but using that the dot spacing would be about 78% of the distance for the red laser. If we had a violet laser at 380nm (the limit of the human eye) its more like 57%. So possible to do. but accurate measure measurement of the dots spacing would be harder (putting aside that I didn't take much care in getting as accurate a measurement as possible).

@stevenwillis548

3 ай бұрын

@@ElectromagneticVideos It's absolutely amazing how we can make measurements that are decades finer than the technology would seemingly allow. I'm getting the urge to refresh myself in physics again. Thanks again.

@ElectromagneticVideos

3 ай бұрын

@@stevenwillis548 Yes - is really is! And finer than we can see with a microscope!

that was awesome

@ElectromagneticVideos

3 ай бұрын

Thanks!

I CAN NOT believe that this channel is real......thank you for watering our theristy for knowledge in physics...by "our" I mean poeple with limited resources here in SUDAN,AFRICA. thank you so much and keep changing the world. Hamza

@ElectromagneticVideos

3 ай бұрын

Hi Hamza, so pleased you are finding my channel useful! My intent is to try and explain and demonstrate things in a way that anyone with a bit of interest can understand and even duplicate with a minimum amount of equipment at home, or in school or university. So cool to hear from you in Sudan - its wonderful how the Internet has shrunk the world! Regards and best wishes from Canada!

@hamzamohamed7935

3 ай бұрын

@ElectromagneticVideos thank u for the rapid reply and keep up the great work and so nice to "meet" you 😊

@ElectromagneticVideos

3 ай бұрын

@@hamzamohamed7935 Great to "meet" you too! If you do any of these experiments, be sure to let me know how they went!

@hamzamohamed7935

3 ай бұрын

@@ElectromagneticVideos I will

Use the surface of a CD as a diffraction grate.

@ElectromagneticVideos

3 ай бұрын

Yes! I wonder if some of the recordable CD or DVDs are transparent enough that you could shine a laser through them?

So basically your grating wound up being 200 lines per inch? IF you managed to get the original grating to print, you would have wound up with a spacing of orders of about 15 mm. But it worked really well actually as you did it. It would be fun to make coarser gratings and see how it degrades the measurement. Looks like you can get away with very few rulings.

@ElectromagneticVideos

3 ай бұрын

Exactly! I tried the 300dpi 1010101 equal black and white sized stripes - it worked, but for such course gratings, the proportionally reduced distance between dots on the screen makes it harder and harder to get accurate measurements.

I don't believe light has a wave length but. Light is a unified field that creates holographic waves that look much like ripples on a pond. It is the transfer of kinetic energy from point A to point B,C,D,E.... and so on.

Firstly, wow, thanks a lot for this informative video. This is the first video I found from this channel today, from the recommendation on some other video from another creator (Fermilab). And its safe to say that I've found a great channel today. Also, I have a query. At 4:23, you say "That's not too hard a thing to do if you know how." But that javascript program looks pretty technical to me, myself being a person who has seen only the tip of the iceberg in programming but still fully well realised the size of rest of the iceberg laying unseen. Like with all that image processing, hardware interfacing, and possibly also file format conversions, and what not. So now, here's my question.👇🏻 I, being a hopeful observational astronomer aspirant still in my undergrad, have always been fascinated by the multi-faceted skill-sets the observatory personnel, like you, possess. And these also include the subjects which aren't exactly included within the field of study, but are still instrumental for the field. Just like how scientific computing is more of a mathematics subject, but since physics students use simulations all the time, its knowledge gives a good base for the programming. I hope you are getting my point. Further examples are subjecta such as the knowledge on computer networks, high-performance computing, image processing, combining of data from observations throughout the world (as in the cases of LIGO and EHT), how to hold computations using super-computers, etc. etc., etc. How do you come to learn all these? Are they taught courses? Are there special trainings on it? Are these learnt on-the-way while working throughout yers in the observatory? Online courses? What is it? Please answer. This has been a long burning question, and I'd be very grateful if this is answered.

@ElectromagneticVideos

3 ай бұрын

Wow - somebody over at the Fermilab channel recommended this video! That neat - I watch a lot of stuff on that channel! Now that I think about it, I was a bit flippant saying "That's not too hard a thing to do if you know how." - I probably should have worded it differently! So I think you basic question is where to pick up all these different things. I think the best advice I can give you is, where you have the option in the current program you are taking, take some courses outside the department. Since you undoubtedly have more than enough physics and math, see if you can take some computer engineering or computer science courses, preferably in with a real language like C or Java (which I used for this, not Javascript - ugh :) Languages like Javascript, Matlab etc are so far abstracted above the hardware you really don't get to appreciate the underlying mechanisms so not as good for getting a deeper understanding. If you go on to grad studies, again try and take a variety of courses to extend the breadth of you knowledge. My undergrad was a combined electrical engineering / computer engineering program. So I got a lot of math and physics from the EE side, and load of computer stuff from the CE side. As a grad student I then took a bunch of courses in physics and mechanical engineering to further broaden understanding of things. Way better to do that in my opinion than to take a second course in some specialized subject unless you are going to eventually specialize in that. After all of that, here is my final advice - never stop learning and be a self learner. You mentioned the code interfacing to the printer - thats a good example of self learning - no course in that - just pick up the reference manual in figure it out! The other things is, know yourself - what you like doing and what are you good at. There are plenty of brilliant theoretical physicists who arnt good at building things or performing experiments. And there are fabulous experimentalists who arnt great at theoretical stuff. If you can figure out where you fit in you will have an enjoyable and rewarding career! I hope that was even just a little helpful. Since your an aspiring astronomer. take a look at this video if you get a chance - I visited the telescopes on Hawaii a few months ago - absolutely fascinating! kzread.info/dash/bejne/lGap18uymszYmdI.html

@harshvardhan4771

3 ай бұрын

@@ElectromagneticVideos "I was a bit flippant" - well no problem in that sir, you've earned it. And, ah yes. That's exactly what my basic question was. It was simply how to widen the knowledge base in other 'helper' fields while specialising in the main field of interest. 😅But as is so obviously visible from my comment above, I am not too good at speaking with brevity and conciseness. But, when you say to take courses, do you mean the basic-level "how to write a program in C?" type stuff which covers mainly the grammar of the language and the basic programming ethics, or the advanced-level "the wizardry of making the computer do exactly as you wish" type of stuff which includes file handling, data handling, networking, etc., etc.? As, if it's the basic level you're saying, then I suppose I've got it covered, as C++ programming was within my school curriculum for classes 11th-12th (I am from India if this confuses you, maybe it helps you equate the educational level I mentioned above to how it is in the west.) Also, since I kind of knew (not because I used it or something, but just a word of mouth I heard somewhere) that MATLAB is used in scientific programming from my school days, I absolutely loved it from the day one it was taught to me in the undergrad (I am currently in my final year undergrad), and later started a personal project to try simulation of two-body orbiting system just to get a hang of what a physics simulation is, and to better my knowledge in MATLAB, so having you say that MATLAB isn't that useful either, is kind of sad. It's nice to see that you too are from an engineering background and ended up in astronomy. I myself am in B. Tech. Engineering Physics (B. Tech. is an undergraduate engineering degree program of 4 years duration in India, if there's some other name by which you know it.) which is somewhat a mixture of Physics and Electronics, more on the engineering side than the science side. I say it's nice to see, as I was actually kind of unsure if I made the right choice by taking up this course, as I actually wanted to go into the full science side of astronomy, but my parents thought that I'd be better off with an engineering degree. And due to this, I am still unsure if an engineering degree (B. Tech.) instead of a science one (B. Sc. or B.S.) would become a hurdle in my goal to pursue astronomy as a career. And finally, thanks a lot for your valuable time and advice.

@ElectromagneticVideos

3 ай бұрын

@@harshvardhan4771 I dont mean basic programming skills as learned with C or any other language - what I mean is using C for its best purpose which is doing low level stuff such as accessing hardware (what we used to do with assembler) So an operating systems course done with C or microcontroller stuff. I didnt say Matlab was bad - but thats its not great for understanding the low level stuff guts of computers. Its is good as a very advanced calculator and for some simulations depending on the complexity and amount of processing needed. Its not great when to have to debug large programs - and it wasnt developed for that. I'm not in astronomy - but really like it and although I didnt do astronomical image processing as a grad student, almost everyone around me worked on that and a learned a lot about it. The great thing about an Eng degree is there are usually lots of job opportunities if needed. And yet still lots of core math physics etc to allow you to move more into pure science if thats where you end up. The problem with things lime astronomy is the very limited number of jobs - I have no idea what its like in India, but over here in some sciences PhDs have to wait for a prof to retire before a position opens up. Thats not generally mentioned by some departments trying to attract students.

@harshvardhan4771

3 ай бұрын

​@@ElectromagneticVideosWow, thanks a lot for your valuable time, and such detailed answers. It's really helpful. I actually had a Digital Electronics course and a Microprocessor Interfacing course with main focus on Intel 8086, in my 3rd and 4th semesters respectively. The Microprocessor Interfacing course had the following units. 1. Basic Concepts of Microprocessors, Introduction to 8086 Microprocessor 2. Internal architecture, Concept of address, data and control buses 3. 8086 hardware specifications: pin-outs and the pin-functions 4. Real Mode Memory Addressing, Introduction to protected mode memory addressing 5. Memory Address Space Organization 6. Programming model of 8086-general purpose registers, special purpose registers and segment registers 7. Physical address generation, data addressing modes, program memory addressing modes, stack memory addressing modes 8. data transfer instructions, arithmetic and logic instructions, flag control instructions, program control instructions 9. Input/Output instructions 10. Types of Interrupts, interrupt instructions, hardware interrupt interface, software interrupts, NMI interrupt 11. Bus Cycle Timing Diagrams 12. Minimum and Maximum mode 13. Subroutines: Call and Return Functions 14. Programmable Interrupt Controller - 8259 15. Programmable Peripheral Interface (PPI) 8255 16. Programmable Direct Memory Access (DMA) Controller - 8237/8257 17. Programmable Interval Timer - 8253 18. Introduction to PIC Microcontrollers, PIC microcontroller overview and features, PIC 16F877: ALU, CPU registers, pin diagram 19. PIC reset actions, PIC oscillator connections, PIC memory organization 20. PIC 16F877 instructions, Addressing modes, I/O ports I actually found it interesting but couldn't actually understand most of it, as I didn't have the basics (Digital Electronics) clear as that subject was taken up during COVID, in online mode. About MATLAB, well yes, I do realise you didn't say it's bad. But I was just sad, because.....you know, ....it's that feeling you have when you get to know the skill you loved learning and also put your own effort to "go an extra mile", isn't completely useless, but still, it isn't THAT important either, so it feels like a partially wasted effort. And also, the lack of job opportunities in astronomy you stated is kind of sad. But why is so? As astronomy is such a wide field, and seeing that, so little people want to pursue it more than a hobby, so I expected that there'd actually be a shortage of people and more jobs instead. That is, I thought the field of astronomy would have been understaffed, but as you said, it's actually overstaffed. So, do you know why is this so?

@ElectromagneticVideos

3 ай бұрын

@@harshvardhan4771 As far as astronomy goes, I dont know the current state of the job market and things like that can go in cycles. The issues with pure science like astronomy is there is a limited amount of positions typically confined to universities and various research institutions like NASA for example. Now do the math - each astronomy prof graduates say one Phd every two years so over the course of the career produce maybe 15 PhD astronomers. The grow of universities and publicly funded science labs is typically similar to the population growth. You can see that the number of PhD astronomers/astrophycisits being produced well exceeds that. And thats the truth for many people in the very pure sciences - CERN has only so many spaces for particle physicists. Other things like engineering, biology, chemistry etc have significant used/demand in industry so there is much more place for graduates to go. So if you want to be an astronomer, find out what the chances you will have getting one of those existing jobs. It may be good if a lot of the people in that field are retiring about now. But there may also be a lot more recent graduates ready to take those positions. I know one astrophysicist who got his PhD 2 or 3 years before me - he spent is working career as computer systems admin. Not a bad job, but not great for someone with his background.

That’s neat.

@ElectromagneticVideos

3 ай бұрын

Its sure is!

I can see Grover teaching in university: "neeeeaaaaarrrr field, faaaaaaar field"

@jeremiahbullfrog9288

3 ай бұрын

🤣

@ElectromagneticVideos

3 ай бұрын

I guess that sounds better than "Fresnellllll Diffraction, Fraunhoferrrrrr Diffraction" :)

For a more accurate measurement of the spacing of the dots you can measure the overall distance and divide by one less than the number of dots.

@ElectromagneticVideos

3 ай бұрын

Yes! A few more, fainter dots on each side were visible when all the lights were off, so marking the position of those dots on the wall with a pencil and then measuring the distance accurately with the light on would really have helped.

@jonathanbuzzard1376

3 ай бұрын

​@@ElectromagneticVideoswhat we did in sixth form 30 years ago. Also increase the distance between the diffraction grating and the wall.

@ElectromagneticVideos

3 ай бұрын

@@jonathanbuzzard1376 Wow - am envious of all of you who had great physics teachers in school!

I've managed to get the hp envy 4520 wireless printer scanner working on debian 12 so this is such a lucky early morning find thankyoy sir!

@ElectromagneticVideos

3 ай бұрын

Nice! If you try it with the files I posted, let me know if it worked! Also, does debian still support the plain old "lpr filename" command or "cat filename /dev/lp" to send the file unaltered to the printer? Would be great if that bypasses the need for my network connection print application.

@user-yr2nb4vr3q

3 ай бұрын

The package I installed was HPLIB or something like that, it let's me configure a computer as a local proxy server and I've successfully conducted the alignment process they run you through, so thanks I'll grab those now

@user-yr2nb4vr3q

3 ай бұрын

@ElectromagneticVideos yeah I work with the debian bullseye build, I can only vouch for the systems I've had running smoothly there have been numerous systems I've crashed while switching from Windows to linux

@ElectromagneticVideos

3 ай бұрын

@@user-yr2nb4vr3q Crashes - yikes! I usually find Linux itself very stable but the various add-ons from repositories are often unpredictable and can really mess up a system. I use Linux for embedded stuff, servers, and some development work - once setup, usually rock solid and a small memory footprint. Havnt printed with Linux in years though ...

@user-yr2nb4vr3q

3 ай бұрын

@ElectromagneticVideos absolutely I took a risk learning with just debian 12 in that regard, for example by default the links in sources.list are http links, you have to go through the process of implementing https transport for apt. But on the whole it's been the best learning experience possible in my circumstances really, I take back ups regularly and do very often fudge my way through the individual challenges, but it's incidental when I can restore from a recent backup. It really changes your perspective you know, for example I haven't spent over a few hundred dollars on a computer for years, because I buy second hand having the benefit of only having to consider hardware specs, it doesn't matter what the software packages are the OS gets deleted as soon as I get her home even if it was brand new, but yeah that circumstance alone gives me the opportunity to afford hardware I normally wouldn't

Nice

@ElectromagneticVideos

3 ай бұрын

Thanks!

Sir, You are a genius to use HP PCL language to print such fine payterns you can also pioneer a new home scale industry to print 3d holographich images and stickers just by pasting it under a sheet of lenticular lense 🎉🎉🎉🎉

@ElectromagneticVideos

3 ай бұрын

Maybe more lucky that it worked than being a genius! :) Unfortunately that series of laser printers is probably to course for decent 3D results from lenticular sheet. But you sure got me thinking. I wonder how easy it is to align a lenticular sheet over an image. There has to be a clever trick given they make things like postcards by the thousand.

@user-lg2hl7hr3j

3 ай бұрын

@@ElectromagneticVideos We can start with a pitch test analysis and then build on the same.

thx v v v much

@ElectromagneticVideos

3 ай бұрын

Glad you liked it!

Fanatastic explanation and show of engieneering wisdom and creativity. I wonder if you used original HP tonner cartridge, if so you should got refund on invalid prroduct (printer) wich is not up to specfication ;) PCL is fun ;) You can send raw PCL to printer but i don't know if this is easy from Java, but definitely possible. But sending over network is more universal.

@ElectromagneticVideos

3 ай бұрын

It certainly could be that a genuine HP toner might be better. Having said that, the normal print quality looks great on this 20 year old printer that I got used for $125 10 years ago - so I cant complain :) I think the higher dpi is more to smooth jaggies a bit than extra detail. If anyone has a newer printer with genuine HP toner it would be great to hear if it can do 600dpi alternating lines (or even 1200dpi!) As near as I could tell, java within windows cant bypass the windows printer driver - but I could be wrong. If anyone knows how to to that, please let me know! Linux or unix users should be able to lpr the file the program generates right to the printer, but I havnt tried it.

@AK-vx4dy

3 ай бұрын

​​@@ElectromagneticVideosIt is required to open/connect to windows print server/spooler but i have no clue if someone done some kind of bridge to windows api in Java. In printer subject: for at least few years if I'm not wrong use led line instead of laser, on one side pixels should be more sharp (they are physical) but on other side it could be very hard to optically isolate one led from another so light will spill to adjacent cells. It may even nicely smooth normal printouts but will have destructive effect on such patterns as you need. Imho result you achieved looks like such spilling for me, but it is only my guess 😉

@ElectromagneticVideos

3 ай бұрын

@@AK-vx4dy Yes - I remember way back when Okidata brought in LED based printers and there were issues about whether they could call them "laser" printers. It would be interesting to know which (all?) printers use LEDS today (huge advantage would be no high speed mirror) and if there is the one-to-one mapping of HP PCL pixels to printer pixels or if that is abstracted now. And as you said how much light spills over. My guess is the spillover should be no worse that what I have seen - or the normal printer would be inferior quality. Funny - all this detail is usually so abstracted in "normal" printing.

I tried to laser print a microscope scale and it failed miserably... I will have to try your method!!!

@ElectromagneticVideos

3 ай бұрын

If you can wait a day or two, I'm half way though cleaning up the source code I wrote ore readable. I'll post it when done. It generates the pattern and send sit to the printer by creating a raw bitmap raster - you should be fairly easily able to modify it to create microscope scale.

@jeremiahbullfrog9288

3 ай бұрын

@@ElectromagneticVideos Fantastic thank you and yes I can wait

@ElectromagneticVideos

3 ай бұрын

@@jeremiahbullfrog9288 Should be up tomorrow!

Great experiment, new subscriber! I guess you wouldn’t be able to command printing exactly on the printer’s dot pitch, but I’d think that a photo-grade inkjet printer might be able to print clean lines with an even tighter pitch. Impressively accurate results given such basic materials! It seems like you could easily get down to just a few nm of resolution just by very carefully measuring the grating pitch and using a longer baseline, maybe 10m or so across the length of a typical basement. (I wonder how accurate the printer’s pitch actually is? I’m guessing it’d have to be accurate to well under 1% to avoid scale errors on the output.) (Great idea btw, to use PCL as a way of talking directly to the print engine!)

@ElectromagneticVideos

3 ай бұрын

I have wondered about photo intended inkjets. However, I wonder of the ink also spills over into neighboring pixels. I get the impression that the higher pixel densities in lasers are to get rid of jaggedness/aliasing rather than increase resolution of the printed image. From what I gather PCL is used for inkjets too, so someone might be able to test it. Just saw your comment changed a bit! yes - it wouldn't take much drastically improve the accuracy of the results as you suggest. I think your right about the printer accuracy - its probably way better than than 1% as you predict. There are some (many) LED bases "laser" printers that use a a linear array of LEDs to write on the drum, so potentially more accurate. One could fairly easily check it with a microscope or even magnifying glass and count the lines along a 1cm ruler or calipers. Would be really tedious though :)

@DaveEtchells

3 ай бұрын

@@ElectromagneticVideos Wow, you're certainly on top of your comments, if you pick up _changes_ in random ones that quickly! 😯👍 I think you're right about ink droplets having some unavoidable dither in their positions, above and beyond whatever the printer is doing deliberately to produce shading. I didn't do anything special in terms of trying to talk to the hardware directly, but played with making hyperbolic resolution wedges for testing lenses and sensors a while back and dither did become a problem at some point but I don't recall any more what that point was. I have an Epson 8550 printer, which claims a "resolution" of 5760 x 1440 dpi, with a minimum droplet size of 1.5 picoliters. I'll dig up one of my test patterns and try printing it on some photo glossy as a start to see what it looks like under a microscope. (Wouldn't it be great if YT would allow inline photos here?) You're right too about how the resolution works. In the case of the 8550, 1440 is the actual pitch of the nozzles in the printhead, the 5760 spec comes from precisely timing when to fire them as the head travels across the width of the page. So grating lines aligned with the direction of paper travel would have the best chance of high resolution. (A secondary question is how consistent the dot placement is in an absolute coordinate system as the paper advances. The timing will need to be extremely precise to have no wavering on the scale of grating lines along their length, and even if the lines were perfectly crisp, if they wander back and forth it'd lead to blurring of the diffraction patterns. (I just found your channel the other day, and *love* it: The content is fantastic, but even beyond that, the discussions in the comments are some of the best on YT too 😃👍)

@DaveEtchells

3 ай бұрын

@@ElectromagneticVideos - So I did just try printing a grating with my 8550 on photo glossy paper, using 10 pixel lines on 20 pixel centers, and it was a mess when I checked it under a microscope 🙁 I don’t think it’s solely due to a lack of precision in the printer’s dot placement though. Rather, it seems that the printer is still dithering, even though I fed it a completely monochrome bitmap at its supposed base pixel resolution. It was clearly dithering because I saw diffuse dots of CMY dies in the background, behind the black dots, even though it was a purely binary black/white image, at what looked like lower resolution. Interestingly, the CMY colors appeared to have been absorbed into the paper’s gelatin coating and thus rather diffused, with soft edges, as compared to the black dots that appeared to be raised half-round structures, laying on the paper’s surface. (This was under a binocular microscope, so there was some sense of shape visible.) I know that the printer has separate inks for “black” and “photo black”; the latter used only when printing monochrome documents. It’s very odd to me that it’d be using any of the colored inks at all in this case, but there were definitely CMY dots present. I don’t have the time to dig any deeper than this, but it’s intriguing to wonder what would be possible if you _could_ control the drop placement directly. From what I saw, it seems that the dithering is happening at a very deep level in the printer’s firmware, so it may be completely inaccessible from the outside. Who knows, maybe there’s even some hardware that handles the dithering? I was in the prepress equipment business back ~1990, selling imagesetters (basically binary laser film recorders, with ~2,400 dpi resolution across 13-19” of film width), and at that time it was very challenging to handle the calculations for halftone patterning and diffusion-dithering with the processors available. OTOH, that was 35 years ago so it’s probably just firmware on a little ARM chip these days. Interesting to speculate about in any case, and it’d sure be cool to be able to talk to the printheads directly 😁 Anyway, now I need to get back to what I should have been doing vs fiddling with grating prints… 😂

@ElectromagneticVideos

3 ай бұрын

@@DaveEtchells Wow - thats a sadly frustrating deep dive into making what should be a better printer make a better diffraction grating. I wonder if the CMY colors are dyes and the black is really a particulate paint to make it really black? As you said, its still very odd that it would still be squirting the colored pigments when all you are sending it is black information. Also so strange that its dithering. Those image setters must have been the cutting edge at the time - and I'm sure they cost a bundle. That was the time when 300dpi laser printers were still in the multi thousand dollar range. I'll bet I know the processor they may have used - some variant of the National Semiconductor 32032 - essentially a VAX on a chip if you know what a DEC VAX was. It had amazing bitmap features and missed getting used in the IBM/AT by 6 months or so. As a student, we had prototype versions of it in the labs for an OS course - when we didnt encounter bugs - and there were many - it was a the perfect processor to learn about computer architecture. Way ahead of the 80286 but plagued with bugs and delays. I will have to do a video about it (actually the 16032 early version of the chip) sometime.

@ElectromagneticVideos

3 ай бұрын

@@DaveEtchellsWell actually after I posted the comment somehow your changed to the comment became visible - so I added the quick update. Nay have been a while after your actual edit - sometimes KZread takes a while to propagate changes, Just responded to your later post about the lack of success with the Epson 8550 - so I wont try and speculate how suitable it will be :) Glad you discovered my channel! Your right about the discussion comments. It was a huge surprise to me - I was actually dreading having to deal with comments when I started posting videos and discovered how much I enjoyed them and learned stuff from them. I'm actually surprised that more KZreadrs don't respond to comments - I get how that would be impossible for channels with millions of subscribers, but not hard to do for small channels like mine (although like today I am sometimes get behind).

Check this out ROY/G\BIV green as neutral roy heat and biv electromagnetic?? Can you divide this precisely

👍

@ElectromagneticVideos

3 ай бұрын

Thanks!

23:00 I wonder why your pen is perfectly able to draw the Greek letters λ and θ (for the wavelength and angle) but apparently has a problem with μ (as μm - micrometers).

@ElectromagneticVideos

Ай бұрын

Funny - never even realized that. I guess I am so used using and seeing u for μ in many text situations I just wrote down u. I'll have to be more careful in the future :)

maybe we can use it to print holograms?

@ElectromagneticVideos

2 ай бұрын

So the issue with that is for a hologram we need to modulate the sine wave that we used for the diffraction grating to contain the image/wavefront information in the hologram. Because of the low resolution (lines per mm) of this method, the we are drastically limited to how much holographic info we can encode. Essentially that means we could get a 3D holographic effect that as long as we look at the hologram from between two of the points of light on the wall. Move left or right more than that and the hologram repeats. So not much 3D useful information can be encoded even if we could modulate the pattern. Now - with a printer that can print in significantly higher resolution - maybe a real 1200 or 2400 lines per inch or more, and the ability to modulate the darkness of the lines, things could start getting interesting. You could compute the holographic pattern for 3D object like cube for example.

Are the waves of the photon wider than the distance between two holes?

@ElectromagneticVideos

3 ай бұрын

Thats a huge question. The "size" of a photon is at times considered to be about the size of its wavelength since it cant easily get though a hole smaller than that. However, in flight it almost has no precise position (OK I am simplifying) and a detector sees it or not based on probability that it falls on the detector. Now to add to the complexity, it can "go though" multiple slits in a grating all at once and if you take enough time to detect a bunch of them you get an interference pattern (like the dots in this experiment). The underlying cause of that is a complex part of the probability function. Thats the best I can do in a few sentences. I'll do a video on it sometime!

@Sonic_Shroom

3 ай бұрын

I think I understand. the width of the wave front is the uncertainty in position?@@ElectromagneticVideos

@ElectromagneticVideos

3 ай бұрын

@@Sonic_Shroom Yeah - sort of - not a bad way of describing it. Perhaps even better, where we see light (or would see it if there a bit of smoke to make it visible) shows the probability of the photon ending up in particular location. The brighter, the greater the probability. So that probability region covers the slits in the grating and provides the interference that determines where a photon ends up. That probability has a cyclic component to it - if you know a bit of math the Schrodinger Equation uses a "wave function" where the imaginary parts provide the cyclic information that we see as wavelength and provides the interference in the probability calculation. The "wave function" gets multiplied by its complex conjugate to get the probability at any point in space time. To some extent the wave function is equivalent to the electric field, and the wave function times it complex conjugate = probability density = power = electric field squared. If that sounds like gibberish, no worries -that's a significant section of a first undergrad quantum mechanic course summarized is few sentences.

There is an interesting video about lasers printers from Technology Connections where it is explained how they work. I don't have here one print to test, but I would expect better results if you print the grating horizontally, because the raster laser travels horizontally to create the dots on the roll. Printing vertically just prints the dots when the laser is on/off at that location and there is a travel time that may be bigger than the laser diameter, leading to lower resolution. The video is at kzread.info/dash/bejne/kaeVpqWwo6Wfh9o.html

@ElectromagneticVideos

3 ай бұрын

Brilliant! What a great thought - I will definitely try it and report back. It is undoubtedly laser printer dependent. I had assumed it was the (visibly course) toner particles overflowing the pixel boundary, but it could be slow turn on - turn off times for the laser. Will be fantastic if just drawing horizontally will all use of 600 or 1200dpi for a finer grating!

@ElectromagneticVideos

3 ай бұрын

Just tried alternating horizontal and vertical lines at 600dpi. Unfortunately the black still spills over in to the white so much that like with vertical,. an all black square results. What a disappointment! Too bad - really was a great idea. maybe it will help on some other printer. Thanks again for suggesting it even if it did help my printer!

@deleterium

3 ай бұрын

@@ElectromagneticVideos How sad to know... But I'm glad you tested it!!

@ElectromagneticVideos

3 ай бұрын

@@deleterium And I still think its worth having the idea out there because it may apply to some other printer model or type!

What is the proof that light is also a particle (photon)?

@ElectromagneticVideos

3 ай бұрын

Look up Einstein's Nobel prize - he got it for explaining the photoelectric effect. Also look up "Ultraviolet catastrophe" which is related to to that and you need quantized packets of energy to make things work out. And finally,. virtually all the photoelectric stuff we used these days - from leds to lasers to displays to cameras were all developed/explained using light based on photons. If the photon idea was wrong, we would be scratching our heads wondering why theory diverges from how those devices appear to behave. The photon is actually more fundamental to light than waves. The waves and electric/magnetic fields we experience (as in this video) are really the effects of the averaging of effects of the gazillions of photons that make up the light.

files plz

@ElectromagneticVideos

3 ай бұрын

Hopefully tomorrow!

You probably should take the time to learn postscript code. it's a much easier way to print to specific measurements and every HP laser printer supports postscript level 3. Also, I found myself worried by your use of the adjacent measurement as the hypotenuse, but then I realized you were only off by 0.02mm which you can't even measure for in the first place with your setup. It might have added a little something to your video to give the measurements of both sides (2000mm and 2000.02mm) just to keep people like me from feeling the urge to do any math while watching.

@ElectromagneticVideos

3 ай бұрын

Postscript: the reason I went with HP PCL was to be able to access individual raw printer pixels - I though postscript was abstracted above the raw level stuff preventing user access to what amounts to printer hardware? Yeah - I could have pointed out the exact difference in length. Its always a struggle as to how much to put in and what to gloss over. One thing I have learned is for the typical KZread audience attention span, if in doubt, less is better.

Wouldn't it be a lot faster and easier to use an unexpensive CD (compact disk) as diffraction grating, given the known and regular spacing of 1600 nm between its tracks ?

@ElectromagneticVideos

3 ай бұрын

I just tried it. With the CDs I have, was not able to get a reasonable beam though the CD, but works reflectively. There seem to be two different grating effects - one from the track and possibly(?) one from the bits (?). There certainty was one nice set of on the screen, You do get some nice, weird effects as you shine the laser on more or less curved track and at an angle. So a bit more confusing a pattern that results but should be possible.