How to Visualize Information Interactively Without Using Electricity
We got LED, LCD Flatscreens, OLED, CRT etc for visualizing information from a computing device or instrument. But if you have followed my previous writing on Venus colonization, you would know that I’ve explored a lot of alternatives electronic and electrical solutions:
- Building a non-electric economy on other planets.
- Building a non-electric 3D printer.
- A non-electric autonomous rover for exploration of the Venus planet surface.
I have covered air powered tools, pneumatic motors, fluid powered computing devices (fluidics), non-electric communication using acoustic signals and fluidics amplifiers.
So to complete the picture, is there a way to display information using fluids, pressure, vacuum or some mechanical control?
Fluidics Based Displays
In fact there is a lot of work done on fluidics based displays. There are many variations of these many using fluidics together with electricity or magnetism. However I will focus on PDDs, that is Pressure-driven microfluidic displays.
Whitesides has demonstrated the display above made up of tiny liquid containers. Colored ink is pushed into the containers with pressure and there is a separate operation to flush the ink out again to clear the display.
There is a lot going on in this field but most is described by research papers behind pay walls.
To get a more DIY hacker like approach to this, to get some videos and hands on examples of how fluidics display technology works, I strongly advice looking at the projects of novelchip on instructables.
What I found really cool is that novelchip also shows a whole fluidics circuit board for controlling these ink LEDs. The circuit board made from acrylic even has an integrated fluidics circuit, that he makes. You can see an illustration of the circuit with the chip and all connects here.
I strongly advice you to check out this project. It is really cool.
If you think a bit further about his approach, you can easily imagine all sorts of other LED displays which he could in theory replicate such old 7-segment displays for numbers:
The individual ink LED’s could put arranged in a matrix like in an elextronic LED matrix display.
Cathode ray tube like ink jets
Okay this is just speculation and thinking out loud on my part. A lot of what I’ve come across and written about here has happened because I thought out loud about stuff I figured should be possible and googled to see if anybody had already done that. You’d be surprised by how often you get an idea and somebody else has already done exactly that thing.
However this particular idea I’ve not been able to find out if anybody has done. All I could find was a sort of 3D printing technique which resembles a bit what I had in mind.
They call it in-air microfluidics. Basically they got two jets of liquid droplets which combine to create solid substance which is deposited to do additive manufacturing (3D printing).
However my idea is inspired by how old oscilloscopes work. Oscilloscopes don’t draw raster images. It is not pixel based. Rather they draw vector graphics. This happens by electric fields pulling and pushing on a beam of electrons hitting a screen which lights up where the electrons hit. So electric fields are used to direct the beam of electrons to the right location on screen.
Well, how about directing a micro yet of ink onto a screen, by exerting air pressure or vacuum on each side of the jet, to change its direction?
In a sense this would be like a plotter. But instead of having a mechanical XYZ arms moving to the right location putting down the pen and drawing, there would be no movable mechanical parts. Instead varying pressures would direct the ink.
The way I imagine this is that we have a transparent horizontal screen. Lines are formed on this screen by jets of ink sprayed from behind the screen. Some kind of coating will have to exist to not make it just fall off or bleed out too much in every direction.
When another image needs to be produced, there is some kind of cleaning mechanism. A cleaning liquid flush the screen leaving it clear again.
What should we call this? “Vector Ink-Jet display”.