Artist and Hackaday reader [Blair Neal] wrote in with his incredible compendium of “alternative” displays. (Here as PDF.) From Pepper’s Ghost to POV, he’s got it all covered, with emphasis on their uses in art.
There’s an especially large focus on 3D displays. Projecting onto screens, droplets of water, spinning objects, and even plasma combustion are covered. But so are the funny physical displays: flip-dots, pin-cushions, and even servo-driven “pixels”.
We really liked the section on LCDs with modified polarization layers — we’ve seen some cool hacks using that gimmick, but the art pieces he dredged up look even better. Makes us want to take a second look at that busted LCD screen in the basement.
We’re big fans of the bright and blinky, so it’s no surprise that [Blair] got a bunch of his examples from these very pages. And we’ve covered [Blair]’s work as well: both his Wobbulator and his “Color a Sound” projects. Hackaday: your one-stop-shop for freaky pixels.
[Blair]’s list looks pretty complete to us, but there’s always more out there. What oddball displays are missing? What’s the strangest or coolest display you’ve ever seen?
Lots of good info, though the cost figures for LED video walls are about 2 orders of magnitude out nowadays with the cheap LED tiles and controllers from China. .
saw your comment on medium (i don’t know why Medium doesn’t allow direct replies!) – Would love to add that info to the article if you have any good links to include, definitely send me an email or post back here. I think I was going off my previous experience with commercial LED walls like Barco tiles, but not so much the DIY route which is obviously going to be much cheaper. I’m planning on updating the article in a month or so when I’ve gotten some new pieces from other internet folks, so I’ll definitely add more notes if you have them! Thanks!
Blair, I have also posted there a link to Zebra Imaging – you may want to add that to the holographic display section (real holography, no Pepper’s ghost or some such).
Best.post.ever.
We need some kind of POV spinner made with Nixies or Neon tubes. :D
I downloaded all the links before the webpages crash.
You mean like this:
https://shop.vexilar.com/productpictureviewer.aspx?id=188&cf=FL12&pc=UP1212D
Spinning a neon bulb was the display of choice for sonar (fish-finder) devices for a very long time before dot-matrix LCD displays became available. In fact, they are still made and used to even today for ice fishing, since LCDs do not do well in cold temperatures.
Go here, http://archive.org/web/
Add URL to box under Save Page Now
Click [SAVE PAGE] button.
And tone down your attention seeking behaviour.
A few years ago I made a screen from touch-sensitive plants and servos. It only kinda worked, but I think about iterating on it sometimes. The documentation is (intentionally slow), so you can jump to the last minute or two to see it in action:
http://www.nishi-broach.com/projects/The-Sensitive-Screen/
nice! I’ll add it to the references when I update
Thanks Elliot! Definitely appreciate the post and all the blinky resources here on Hackaday…happy to add others to the article if any other readers have project they think should be included.
He glosses over (single Wikipedia link) a technology that will be huge in the near future, the “spatial light modulator”.
https://www.youtube.com/watch?v=egBb9o55-BA
Why care about it now? Because by the time you get your head around how it works, well enough to make the most of it, the technology will be much more common and every other display system will leave people thinking pfffft old tech.
For one of the more recent papers on the topic see:
Vol. 55, No. 3 / January 20 2016 / Applied Optics
Realization of real-time interactive 3D image
holographic display [Invited]
JHEN-SI CHEN AND DAPING CHU*
doi 10.1364/AO.55.00A127
My 30-second understanding of the technology:
A real, traditional hologram is made using lasers projected onto a photographic medium. This medium is then developed, and it recorded interference patterns, which can be turned back into a hologram with an additional laser.
This technology seeks to replace the photographic plate with an LCD that shows *computed* interference patterns. The laser can then reproduce the “original” image that only existed in a computer.
This can result in a REAL holographic display. However, the obvious drawbacks are: you need a VERY fine resolution LCD display, with pixels on the order of the wavelength of the laser light — this will obviously increase the cost. You also need to calculate the image to put on the LCD, which probably has some very nasty math, since every part of the hologram has the information needed to display the entire scene. This means more computation power, and more cost.
The demo is also monochromatic. I would imagine that color would be possible, if you had three lasers and three times as much computational power, assuming that the LCD was fast enough to switch at three times the frequency.
Still, this tech looks VERY cool. It will be interesting to see how it progresses, if it ever become affordable for mere mortals to own.
In any cheap picoprojector from ebay you will find display module fine enough to create hologram. The problem with realtime hologram calculation is much worse. There are a lot of CGH capable GPUs, but all graphic card manufacturers totally hide all information about programming GPUs in native code and definitely would not release this info to the public. So, the only way is to use a dozen of graphic cards in parallel running all that OpenCL crap ineffective for CGH.
Yes, but tech capabilities are doubling and prices halving on a regular basis, plus there are more refined methods that track the user’s eyes so that only the relevant subset of the wave-field needs to be computed.
Tracking the eyes is NOT needed at all for this. Ever see a static hologram made from a photographic plate? Those don’t track your eyes.
AFAIK, Zebra Imaging is making “printers” and displays using this idea:
http://www.zebraimaging.com/
I see that “mechanical” displays are mentioned. But nothing specifically about the Nipkow “spinning disk” displays that were the basis for the earliest TV broadcasts.
HaD–a word in your ear:
You need to require the people who write your article headlines to have English as their FIRST language, not their second or third language.
https://upload.wikimedia.org/wikipedia/en/0/03/Aybabtu.png
Not enough pixels there, mango.
Or enough of the rest of it…
https://youtu.be/8fvTxv46ano
Makes me wonder: What type of display was the MAIN SCREEN that they TURN ON?