In May 2001, while working in BT research, I had an idea – how we could use the skin surface as a new platform for electronics. I grabbed a few of my colleagues - Robin Mannings, Dennis Johnston, Ian Neild, and Paul Bowman, and we shut ourselves in a room for a few hours to brainstorm it. We originally intended to patent some of the ideas, but they weren’t core business for a telecoms company like BT so that never happened.
Now, 12.5 years on, it is too late to extract any value from a patent, but some of the technologies are starting to appear around the world as prototypes by various labs and companies, so it’s time is drawing near. We never did publish the ideas, though a few did make it out via various routes and I talk about active skin in my writings more generally. So I thought I’d serialise some of the ideas list now – there are lots. This one will just be the intro.
Today we have implants in the body, and wearable devices such as watches and cell-phones in regular proximity to our bodies, with a much looser affiliation to other forms of electronics such as palmtops and other computers. With recent advances in miniaturisation, print technology and polymer based circuits, a new domain is now apparent but as yet unexploited, and offers enormous potential business for a nimble first-mover. The domain is the skin itself, where the body meets the rest of the world. We have called it active skin, and it has a wide range of potential applications.
Active skin layers
Stimulated by MIT work in late 1990s that has shown that the skin can be used as a communications medium, a logical progression is to consider what other uses it might be put to. What we proposed is a multi-layer range of devices.
(actually, this original pic wasn’t drawn quite right. The transfer layer sits just on the skin, not in it.)
The innermost ‘tattoo layer’ is used for smart tattoos, which are permanently imprinted into the lower layers of the skin. These layers do not wear or wash away.
The next ‘mid-term’ layer is the upper layers of the skin, which wear away gradually over time.
Above this we move just outside to the ‘transfer layer’. Children frequently wear ‘tattoos’ that are actually just transfers that stick onto the skin surface, frequently on a thin polymer base. They are fairly robust against casual contact, but can be removed fairly easily.
The final ‘detachable layer’ is occupied by fully removable devices that are only worn on a temporary basis, but which interact with the layers below.
Above this is the ‘wearable layer; the domain of the normal everyday gadget such as a watch.
A big advantage for this field is that space is not especially limited, so devices can be large in one or two dimensions. However, they must be flexible and very thin to be of use in this domain and be more comfortable than the useful alternatives.