Flexible Screens and Bendable Smartphones: the Science behind this Emerging Technology

Bendable Smartphone of the future. Image credit to Smarttechnology

Bendable Iphone of the future. Image credit to Prowl Newspaper

I had my first mobile phone in 2007-one Nokia 2310. Then it was like one precious jewel-honestly if you give me that phone now, I'll throw it into the closet and flush it away-and I could remember that I played all the ring tunes on it over and over again, and also listened to news and jamz on radio stations with it. It was just so sweet. I used to admire the screen and always changed the theme colour-from blue to other colour mixtures I can't remember. But looking back and making comparison with the type of screens we have on phones now, I made a joke that the display of those old mobile phones and that of the current day call-only dumbphones are just films of groundnut oil on water; but that's a joke anyway.

There has been rapid transformation in phones display and hardware from what was obtained back then to things like LCD (liquid crystal display), AMOLED (Active Matrix Organic Light-Emitting Diode); and now the current buzz: flexible display, bendable screens and bendable phones. These new trending buzzwords in the smartphone tech world are not really new ( I mean in terms of the basic, fundamental scientific principles behind them).

Back in secondary school (high school) and in the first year of university when we did the basic sciences, we were taught that metals and semiconductors like silicon are electrical conductors while non metals like plastic and rubber are electrical insulators, meaning that plastics and the likes do not allow current to flow

Flexible Display. Image credit to Treehugger

through them. However, I would say that information was limited in scope maybe to accommodate the curriculum meant for such level. But as far back as the 1970s, three scientists, devised ways through which non metals like rubber and plastics when subjected to certain conditions conducted electricity like metals; this work led to the concept of polymeric conductivity (polymers-composed of thousands of monomers, if you remember your secondary school Chemistry-conducting electricity). The research was so phenomenal and filled with endless prospects for the field of material science and engineering that the three scientists, Professors Alan J Heeger, Alan G. MacDiarmid and Hideki Shirakawa behind it were awarded the 2000 Nobel Prize for Chemistry for it. 

The area of polymeric conductivity in material science has so much expanded since 1970s, giving rise to possible applications in the future such as flexible electronics (electronic devises whose electricity conducting parts are made of polymeric conductors and hence allowing you to bend them, unlike metals used in current devices).

In fact, one of the expectations I had for the Samsung Galaxy S5 before its launch was it was going to come with a flexible screen display, and I was mildly disappointed initially because it fell short of that expectation despite all the rumours. But that expectation was not met because of one of the biggest challenges facing the industrial application of polymeric conductivity; and that was what took away that mild disappointment (though some other expectations I had for the smartphone, and which are extremely feasible, were not met with, but their analysis is not the focus of this blog).

According to a new research published in the Proceedings of the National Academy of Sciences by scientists from Stanford Univetsity and the University of California Berkeley and led by Professor Andrew Spakowitz, these conductive polymers at the molecular level exhibit what they termed structural inhomogeneity. In other words, plastic conductors conduct electricity at different rates in their various parts at the molecular level such that bending or flexing them significantly alters the rate of current flow, reducing the electrical conductivity (and I now understood why the Galaxy S5 probably fell short of my flexible screen expectation--some work still needs to be done). Professor Andrew Spakowitz and his team I guess are working to find solutions to this current flow-impeding structural inhomogeneity; and their success, which is on the high side of prospects, will definitely make our dreams of having bending smartphones and tablets and other electronic devices in our hands come true because, for one thing among so many things,
I will no longer panic if my bendable smartphone falls from my hand.