Applied Science - 2018-11-21
This electroluminescent paint can make almost any smooth surface glow, even flexible objects. I show how to use it, and demo a custom multi-channel driver circuit that I designed. https://hackaday.io/project/162240-multi-channel-electroluminescent-driver https://github.com/benkrasnow/EL_driver_multi https://www.lumilor.com/ https://www.coastairbrush.com/categories.asp?cat=386 https://en.wikipedia.org/wiki/PEDOT:PSS http://www.testequipmentdepot.com/metcal/fluid-dispensing-systems/dispensers-controllers/dispensers/0-100-psi-economical-digital-dispenser-dx250.htm https://www.amazon.com/KSGER-Soldering-Electronic-Elements-200V-260V/dp/B07F5J5WXM https://www.amazon.com/Heat-Scientific-Ceramic-Resistive-OD30T1-2/dp/B074Z62BDK/ https://www.mcmaster.com/6699a8 https://www.digikey.com/product-detail/en/3m-tc/1-2-6-1183/3M9895-ND/2649440 https://www.patreon.com/AppliedScience
EL TIPS: EL emits light only during voltage change. Square wave is not very efficient, light flashes on only during rise & fall. Trapezoid is better. Most efficient drive waveform is Triangle, but with the sharp "tips" of the triangle rounded or flattened (the sharp "tip" of the triangle waveform creates a large current / EMI spike). There is also a maximum optimal frequency, after which the light goes down, the current & heat go up.
For best efficiency, use a silver substrate (i.e. silver ink or plating). The best clear conductor is Orgacon (now from Agfa, originally from Sylvania). EL lights are not that efficient or bright. The Higher the Brightness, the shorter the life (days or weeks). Run at very low Brightness (current) they can run for decades. Brightness is proportional to P-P Voltage. Lifetime also depends on the dielectric and the substrate heat dissipation. The operating voltage is typically between 200 ~ 400 Vp-p
I used to design power supplies for these around 2006 for a company making large EL sheets with silk screen printers for advertising displays.
A rounded triangle wave? You mean a sine wave?
@Chrysippus No, a Trapezoid with a very short time flat Top & Bottom. Less EMI & current spike if the tiny flat is actually an arc, like the top of a sine wave. A sine wave is still more efficient at generating light than a fast Tr/Tf square wave, but causes more heating. Tested: saw-tooth waves , parabolic waves, hemispheric waves, etc., the Triangle won above all of them. FYI: The EL is a capacitor (<1 to >300 nF) depending on dielectric and area. This can be measured fairly accurately with a HV DC power supply , a series resistor and a scope. Many "capacitance" meters will give incorrect results. The "ramp" of the triangle (or trapezoid) should be flat, which means that the power source should provide a constant current.
@shazam I think you're talking about bandwidth-limited or low-pass filtered or signals omitting the higher harmonics.
@Mike Guitar A triangle wave like this: https://youtu.be/L5MMcVzhDRI?t=16 Play to the end to see the peaks sharpening. This should be the current waveform for maximum EL efficiency.
@shazam If light is only produced by leakage, wouldn't it be a good idea to let the EL capacitance resonate on a specified frequency to use the supplied energy spikes more efficiently over several periods.
Just charging and discharging by switching voltages (square-wave) or switching constant-currents (triangle-wave/saw-tooth) may be a big part of the inefficiency.
So I would expect better results by combining it with an inductor to let it resonate at a favorable frequency (maybe to control efficiency, power transfer and dampening) after a periodically applied charging current (limited) to the LC-circuit. Maybe it also needs to be sychronized...but it should do the low-pass filtering by itself!
Does anyone drive EL displays that way?
You are just mind-blowing! I find every video you make, and the extent of your interests, incredible!! Thank you for this amazing and inspirational (and educational) channel.
I think the same. Could not express it that good.
What Lank said
Echo what Lank Asif said, only adding some extra Wows!
Easily most detailed, intresting and Professional Youtube-channel.
I've seen cars painted with this stuff, it's definitely a trip to see. You always do experiments with the coolest most interesting things Ben. Your uploads never disappoint. Thanks.
Yea I was lucky enough to see a car that had this stuff on it and it's definitely a head turner.
I wonder if you could "spray" the display directly onto a PCB? So the first capacitive layer would be an exposed PCB pad. Would make the wiring a lot easier and maybe allow more complex figures or other cool stuff.
I don't see why that shouldn't work. Just leave a second trace exposed to connect the top layer.
You just gave me the most epic idea! Imagine painting PCBs with this before finally sealing them so that you could have gaming (or any on show build) have its hardware light up according to IRQ calls/link power to the painted PCB so that whenever a particular process runs it lights up (you make the power assignable to whatever process you want). In time you could even have it so your hardware glows red when you die in a game or get an email. I know something similar could be done with regular lighting but this would look totally different.
Just an idea
@Lank Asif Would prob wear off pretty quick and or shock you.
@Steve just Steve but it's be under the usual insulating layer (just make sure it's transparent). I'm just thinking of it as a commercial option, not really for a personal project - I should've made that more clear.
@Lank Asif I don't game so don't really no what I'm talking about, just thinking about how a radio or remote control buttons wear from use. I would think a controller would be much worse especially at the rate some of you play those things.
This is phenomenal!
I had never heard of this before your video. Thanks!
Depending on the paint viscosity and the compatibility with thinners, it would be intriguing if this paint could be directly applied by an ink jet printer.
You should take this out of the lab, apply it to a garment and send it down the runway.
yes, you would only need to cater the delivery of each chemical to the paper or material. switchable cartridges, sure
This is unfortunately high voltage AC driven. I don't know if you want those electrodes near your body. They might come undone and start shocking the wearer. Some thing he didn't get into in the video are that this is more accurately called AC Electrolumenescence. LED are also electroluminescent devices., but the AC EL devices are cool because electrons and holes aren't actually injected from the electrodes into the photoactive material or phosphors to recombine like LEDs. The dielectric material simply blocks charge injection and only allows the photoactive material to only feel the electric field. The high strength electric field causes the electrons and holes trapped in defect states within the photoactive material to free themselves and shoot through the material like a bullet (many times faster than in LEDs). The kinetic energy is transferred to other electrons and they to become excited (impact ionization). The electrons and holes recombine as they travel across the thickness of the photoactive material and emit light. After a certain short amount of time the electrons and holes accumulate at the interfaces of the film (like a capacitor) and then the films reaches an equilibrium (becomes charged). At that point the device doesn't emit anymore light. To keep the devices emitting light the field is flipped at a rate such that the electrons and holes won't accumulate at the interfaces to much. In physics this charge transfer is called a displacement current. The way this differs from a capacitor is that it is losing energy to excite electrons into radiative energy states within the material. Something that most dielectric insulators don't have.
P.S. Love your videos. I hope to have a home lab just like yours one day. I'm a Physics Ph.D. candidate researching Perovskite LEDs. They are cheap and easy to make in a simple lab. I can describe the process if you want to try it sometime.
I have used those el transformers. The shocks from them aren't that bad
Tech Ingredients, re: sending EL-painted garments down the runway - I stopped reading about the physics as soon as I pictured the models tearing malfunctioning electrical clothing off of their bodies. Smoking hot!
@Johnny Hammersticks describe the perovskite led process, please!
I'm continually SO impressed by Ben and his channel. That solution to change the timing is absolutely brilliant and I would never have figured that out. I am constantly learning new things here.
Would be cool to apply the layers in reverse and paint the inside of a glass or vase.
Fantastic! I find so many pearls in the subtext of your videos. The displays and drive circuitry on their own are amazing, but so many other little things. Just seeing you harvest parts from the AdaFruit Trinket. I'm not sure I would have tried that. I had no idea the parts would survive the heat, or come off so clean! There's more, but I'm going to stop gushing and just say thanks (again) for your attention to detail on such an excellent subject. Well done!
I am somewhat ashamed to call myself an engineer every time I watch your channel. You are just on a different level; truly inspiring.
This is absolutely incredible. I’m an electrical engineering undergrad, and I can’t wait until we are able to paint displays on things!
"ITO" at 4:52 is indium-tin-oxide for anyone who is wondering. It is the go to transparent conductive coating, used for transparent deicing heaters on aircraft windshields, electronic displays, miscellaneous optoetelectronics, etc. It is usually deposited by essentially evaporating it and and then condensing the vapor on a substrate. Pretty energy intensive and expensive for large substrates as you will typically need to do the deposition under vacuum.
This channel is the only one that surprises me in variety, creativity and expertise. Keep it the deep explanation as other channels skip the process for some reason. Great video!
Your videos inspire me to stick with hard projects and see them through. The DSKY was unbelievable!
This is so inspiring. I tried make a simple EL light some time ago and had little success. I was using regular paint brushes on an ITO sheet as substrate and copper tape as the other electrode. Almost all of them short circuited. This is so neat and clean. Btw, I could find cheaper version of the same material on ebay.
Been meaning to do a detailed look at the commercial electroluminescent wire for some time now. Did all the measurements and tests but just never made the time to do the video. Great to see the work you have done. No way will I ever spend that kind of money on an experiment so thanks for putting it out.
This technology has been in use for a while in the aviation business--mostly for position/navigation lighting on military aircraft. Its lower brightness is perfect for close-quarters, tactical flying and air-to-air refueling at night. It is super light in weight when compared to incandescent, fluorescent, LED, and LCD lighting. It's also quite rugged. Very cool stuff. Thanks for the great video!
a) Wonderful video as usual, Ben!
b) A note for those who have mentioned laser cut solder stencils, I agree that they're often not optimal. For small jobs, a friend of mine and I worked out a process to use post-it notes as solder stencils instead of kapton. 3M makes a post-it that is fully coated in adhesive (instead of just along one side). We used a 45W laser to raster scan various stack-ups of notes on an aluminum base. Assume the bottom note will be sacrificial, then peel up the top one or two notes--2 seemed to be about the right thickness. If you tweak the settings in, accuracy is quite good. We did 0402 and 0.5 mm pitch QFP with good reliability.
Using a plastic squeegee and well-cleaned boards, we were able to get a dozen PCBs out of a stencil. Using a stick on stencil is nice. Once you get it aligned and stuck down, it's not going anywhere.
So very cool! I was working with EL lamps (screen printed process). being able to rapidly prototype or one-off is awesome! love that you have given the driver whistle the boot as well.. amazing thank you!
The level of science you do in your garage, is outstanding. Thanks for that. Learning more here than I could in many universities out there.
Your imagination and follow through never fails to amaze!
Are there any tristate high voltage drivers that you have or could consider to avoid the pixel flip flash on the matrix driver?
Incredible work with the matrix driver code. I can imagine how long that took.
Great video :)
I'm wondering if multiple color channels could be created with multiple control leads and a common bus? I see creating beautifully lit and dimmable art, control panels for things like music production to common household switching and car dashboard displays. I have an airbrush kit with a few brushes and enough electronics knowledge to be dangerous lol.
you could theoretically make a 1024 by 576 display if you had enough of those driver circuits and add a contrast knob at the end of all the outputs for more flexibility to use it as a monitor.. that's really fascinating to me. edit: thinking about it a little more what if it was just a max and minimum brightness setting so you could either make it more power efficient and darker or make it less power efficient and brighter plus being able to control the contrast at the same time? is it possible to do that/is it easier than a contrast knob?
You can change the voltage limit of the LT3468 by simply changing the transformer selection. It's based on the flyback waveform so as soon as it detects it's no longer pushing into the cap it's going to stop charging regardless of the voltage there. You could also in that case switch to using something like the LT3420 with automatic top off to vastly simplify your circuit. This works don't get me wrong, and comes with some features you wouldn't get otherwise like the ability to select your own voltage thresholds. If you were looking to make this into some kind of a product though those are definitely changes I'd make. If for no other reason than it removes the need for software control to keep the circuit from going out of spec.
2 videos? 😱 I always love them and want to thank you very much for making them
The other guy have more thumbs up. You where too late!
Each of Ben's project is far of for anyone, amazing that someone can come up with all of his stuff
You're hell of a genius man. You not only your material sciences but electronics as well. I wonder how did you learn all that and with so much detail.
I am really glad that I found your channel.
Clearly you've taken EL Tech to a new level. Displaying a recognizable video to a EL Matrix Display is incredible. :) I tip my hat to you sir!
This is really cool. A few years back I tried making a custom EL driver that would eliminate the audible noise- in my case it was for costuming a rock band and the EL driver noise would be picked up by microphones and especially guitar pickups. Whenever I increased the frequency above about 10khz the brightness would fall off and I came to the conclusion that the phosphor needed the lower frequency. I guess I was wrong, it must have been a limitation of the transformers. You going to be selling this driver? You could take over the market, no one else has anything like it (last time I looked).
ZnS:Cu looks like 10khz is 100% intensity, 20khz 83% , 30khz 44%.
people hear to ~15-20 khz
You need to be running a sine wave, not square wave as sine eliminates 90% of the audible noise and increase lamp life. Both the voltage and the frequency dictate brightness and color hue. Triphosphorus White EL lamps can change over a wide color gamut by just changing the frequency as they use multiple phosphors that emit at different optimal frequencys. Single phosphor White lamps are made with a fluorescent layer printed on a single Blue/Green phospor layer to shift part of the light output from blue/green EL to White. The voltage can be 80-160v RMS at anywhere from 400 Hz to 1.6 Khz with and average of 800 Hz for most white lamps.
My notifications got messed up and still managed to not miss a video. This was one of my favorite ones yet. I've been really interested in this paint, but it seemed like it would be really expensive. $400 for everything is cheap. I would like to see more video of what you made with it, maybe put this paint into a new project. I don't care if it's just painting a fitting or a custom decal on a project box. I always appreciate how much work you put it and the research you do that most other youtubers don't bother to. The King of Random hits Wikipedia for five minutes not even checking sources, while you seem to research scholarly articles and patents for a month. Thanks for sharing, awesome video as always!
Pfieuw, thats an amount of effort, stunning results, congrats! The blue/green looks like a VFD display, very nice. Like others just mentioned before, it would be nice if it is possible to print it, especially for very fine details. Just wondering, is it possible to create contrast differences, like the amount of gray used in black and white images, by applying more paint or less paint or does the thickness makes no sense at all? If you can do this you can create 'depth' or shades.
Another question, is there a difference between the colours, power consumption, required voltage etc and is it possible to create other colours by mixing it with some chemical? What will happen when you mix two colours and spray it, does it work?
This is fucking impressive, I am blown away by how cool this is! Makes me wish I could afford all the materials to make my own. I think it's awesome you went the extra mile to make your own driver circuit too. Kudos!
I had no idea the HV chips existed. I've made displays using triac pairs switching a standard driver, but there are big issues running an EL driver with variable loads. They'll shut down if the capacitance is too high, or low, so switching everything on or off can cause unexpected issues. This is a really neat solution.
Really cool stuff, as always. How did you learn to do electronics? How many degrees do you have? If you work, what's your job? What software do you use to create circuit layouts? What do you use to write and compile your Arduino code? Thanks!
Well done Ben, this is stunning.
Awesome video, I am always astounded by the varied topics your videos cover.
Terrific video, project and explanations! 99% is completely over my head.. I'm curious how long (roughly) you spend on a project like this? Both total hours as well as time spread out (ie 24 hours across 8 days or so)
I have been observing the tattoos people have, and have been thinking about how cool it would be to have programmable tattoos. I guess what I think would work would be small granules or beads that could be programmed for position and color or reflected wavelength. That way as people aged and things sagged and faded the tats could be modified without expensive rework. I'm not really into body art myself, but something practical that could be changed at will would be useful. Maybe a tattooed wrist watch, sunscreen or something.
This may be off topic but that paint reminded me of it.
This is really neat! Can you make more videos on superconductors/diamagnets/paramagnets?
Ben your videos just keep getting more interesting, keep up the good work :)
Super impressive dude, excellent work. So much work, but super interesting, well worth it.
Wish i could get my engineers on this level :-/
Try refilling inkjet/bubblejet cartridges with this kit and printing on transparency film. You might be able to print custom displays with off an off the shelf printer!
I can't see very many reasons why it wouldn't work. It might rapidly plug the print heads, and the conductive components could mess something up. I'm not extremely familiar with the details of inkjet printers, but I know many of them have four different color cartridges. You might also have issues with the yellow dot codes they print on everything to trace counterfeit money causing shorts, though. If that's the case you may be able to clear the shorts by pulsing the display with a few extra amps to vaporize any shorts.
Since you need to print one component at a time you'll have to make four different images to print on the same page, one after the other in four passes. If the dots cause a problem, it can be solved if you find a printer that will run with a single cartridge, but it would be ideal if you didn't have to swap cartridges between passes.
Amazing! First of all, you are so -so smart but also your way of explanation is direct and quick, not any bla-bla-blaa and not fasting time. You are the gift for all us!
The entire time I was watching this I was thinking to myself, 'I'd have to figure out how to run video on that cross matrix and I'd totally have to rickroll people with it.' And sure enough that's exactly what you did. INSTANT like & sub from me. Keep of the great work!
Just make a giant 7 segment or a character segment display! I have been thinking about doing something with electroluminescent paint these days, and you happened to make a video about it. You rock!
Fantastic project! Thank you for sharing. Can you share more details about your reflow setup? You say you power the hot plate from a bench supply. Do you man the hot reflow station supply you linked to? What voltage do you run the heating elements at? And where did you get the insulating tile? Again, thank you for sharing your great work!
One thought came to my mind while you talked about the copper layer. In another (great) video, you showed how to deposit copper onto platics by using a carefully balanced redox reaction. Might it be easier to just spray the copper onto it ? Could such a coating be then used to deposit other metals onto the copper coating by electrolysis ?
With solar reflective paint being so expensive, wondered if you could test various cheap home made paints for its IR reflectivity, which people could use to cover their roofs with.
Only Ben could Rickroll people with a homemade EL display matrix.
This Old Tony - 2018-11-22
I was staring so intently only to be rickrolled. Love it!
pmgodfrey - 2018-11-23
You need to put some of this on your shop toys to try and one up AvE. He doesn't have a glowing CNC machine.........yet.
The Drunk Turtle - 2018-11-23
i just use hyperdrive waste from your space workshop to achieve a similar effect.
nickbownz - 2018-11-28
@AEON you find the competitive option that isn't a blatant forgery of this system. technology, especially limited application technology, costs money.
Dmitry Granicin - 2018-11-28
You know the rules, and so does he ;)
Garbled User - 2019-02-09
You can do better than this to illuminate your your C&C. Use cherenkov radiation instead.