Posts Tagged ‘inductive charging’

I have discussed the need for wireless charging on several occasions and mentioned a new ultrasonic technique here. One issue with the ultrasonic method is inefficient penetration of materials. For example, a simple mobile phone case has the potential to prevent charging. My version of transparency demands that the user have to do nothing to connect. It needs to occur well ummm…. transparently. I mentioned the problem with inductive charging being range and the need for a one meter range. Well, I was mistaken about the limitations of inductive charging. In fact, mistaken is an understatement. Back in 2007, Karalis, Joannopoulos, and Soljac published “Efficient wireless non-radiative mid-range energy transfer” in Annals of Physics. Apple was more observant than I am and picked up on this. The result is their patent “Wireless Power Utilization in a Local Computing Environment.” It describes wireless charging over about a one meter range. The near term impacts of this are small but the long range impact will almost certainly be huge. This isn’t a one off patent from Apple. They have already been looking at more typical very short range inductive charging solutions. For example patent 7352567, “Methods and apparatuses for docking a portable electronic device that has a planar like configuration and that operates in multiple orientations”, describes a wireless charging and data connection base for the iPad. It’s interesting for also including a wireless data connection in the base.

In terms of long range potential, imagine having your phone charged while you drive your car or while you sit at your desk at work or when you sit in your recliner at home watching TV. Freeing the phone from its battery limitations opens it up to become your primary computing device where you are able to rely on it always being there. This is huge. Google, Apple and Microsoft are all working on syncing through the cloud. However, that only goes so far. They are syncing data and not applications. Also, it will be a long time before truly high speed wireless data is everywhere.


I mentioned earlier the issue with battery technology and my dream of the phone as the primary computer. One solution is to make chairs with built in chargers. Imagine sitting at your desk and having you phone automatically charged. Your mouse, keyboard and display are linked wirelessly. You get up and go into a meeting room. When you sit down, wireless charging circuitry in the chair keeps your phone from running down. A wireless link causes the screen built into the table to go active and the keyboard and mouse in front of you go active – all linked to your phone. Effective wireless charging technology would mean that today’s battery technology would be adequate. The problem is with the charging technology. It doesn’t really exist. There are inductive chargers but to be efficient they require that both ends, the phone and the charger, be in close physical proximity with separations on the order of centimeters. For what I want, charging needs to ideally be effective over distances of a meter but at least a third of that. A new approach is being developed by uBeam. This is a very small company. Actually the company is just two college students. That said, they are trying a novel approach using beamed ultrasonic waves. If it works as advertised then another part of the puzzle needed for true convergence just might be falling into place. I am trying to find out more about this to see if it is something to get excited about. Stay tuned.