The world of the future is often characterised by everything being virtual or touch-screen. Now, we're at a point where this could become normal enough in the future, thanks to the work of researchers in France and the United States.
After some experimentation, a possible "disposable electronic touch pad" has been created, as RSC reports. The concept sounds futuristic but the actual production seems surprisingly plausible. The pads are made of metallized paper: paper coated in a layer of aluminium. The aluminium layer is only around 10nm thick, but is then covered with another very thin film of transparent polymer.
The paper is already produced commercially, and is used for shiny labels and glossy book covers. For a square metre you can expect to pay out a wallet-crippling $0.25, so it's hardly expensive either. Already, the work has allowed the researchers to develop an alarmed box with a keypad that requires a code, so the real-world ramifications could be experienced very rapidly.
One key to the system is that the paper already has the essential elements of a capacitor, with the surfaces of thin metal film being able to collide when something is touched. To try and convey the rapid pace this project is moving at, the team have two different capacitor configurations. One requires two sheets of paper stuck together, while the other uses a single sheet.
The human body itself makes a surprisingly effective capacitor, so when the finger touches a key there is an increase of capacitance at the key. The external electronics detect this. While sounding well-developed already, more work is being performed to try and usher in a new age of touch-screen everything.