We spent most of last week at the Flexible Electronics 2014 conference in Phoenix. This was an extremely technical conference, all about hardware and componentry and not even a tiny bit about consumer-level products. (More than a couple of speakers talked dismissively of the current state of consumer wearables, saying “everyone has one.”) If you wanted to know about substrates, nozzle size, and sensor chemistry, this was the place for you.
Yet as impenetrable as many of the sessions were, some fairly exciting trends started to emerge.
One speaker, Michael McAlpine of the Princeton Institute of the Science and Technology of Materials (PRISM) talked of self-powering wearables, noting that people typically consume 2000 or so calories a day — enough to generate about 100 watts. Perhaps, he mused, it would be possible to power a cardiac pacemaker simply through respiratory effort. He showed an ear printed with biomaterials, with an electronic coil built in; the coil could hear frequencies not just in the kilohertz range of human sense, but in the gigahertz range of microwaves.
Corning was promoting its Willow glass, which is extraordinarily flexible and manufacturable. The company says it is far smoother and more transparent than PET plastic, and nearly as flexible. Smooth is good because it’s easier to print electronics on a smooth surface; transparent is good because PET apparently puts a yellow shading on transmitted light.
The military (particularly the Air Force, but also the Army) is spending a lot of money on biomed wearables. The goal is developing Band-Aid-like patches that can sense trace amounts of chemicals in sweat that are telltales of stress or hypoxia. This requires a lot of technology in a small space; you need to absorb the sweat, analyze the sweat, recognize a particular chemical, measure it in trace amounts, and transmit the findings to a system that can, for instance, raise a pilot’s oxygen supply if he’s running short.
The general expectation is that buttons will more or less go away on wearable devices, replaced by sensors printed on substrates like plastic or flexible glass.
Transparent touch-screen circuitry, like what’s on your cell phone screen, currently uses a material called ITO — Indium Tin Oxide. It’s expensive, and there are concerns that supplies of indium (which is primarily produced in China, Canada, Japan and South Korea) could become constrained. Several vendors are experimenting with silver nanowires, which create a transparent mesh when sprayed on appropriate substrates.
There’s more, but we’re still digesting it. We’ll post as we get to it.
