[LINK] Some shocking news about wireless electricity

[rchirgwin at ozemail.com.au]

Stewart Fist wrote:
> Stephen wrote:
>   
>> There are three basic technologies for wireless charging: radio,
>> resonance, and induction.
>>
>> Radio charging is well suited for charging low-power devices at long
>> distances -- some 30 feet away. This technology is ideal for trickle-
>> charging advance RFID chips affixed to, say, palettes loaded with
>> products in a warehouse.
>>
>> Resonance charging makes sense for robots, cars, vacuum cleaners, and
>> other applications that require massive power over minute distances --
>> essentially making contact with plastic, but not metal.
>>
>> Toothbrushes now, and random gadgets will very soon, use inductive
>> charging. This technology uses a coil to create an electromagnetic field
>> across a charging station surface. The device then converts power from
>> the field back into usable electricity, which is put to work charging the
>> battery. 
>>     
>
>
> I don't agree with the distinction between resonance and induction.
>
> Who invented this distinction?
>   
Infoworld. Or better, mis-Infoworld. The article was pretty garbled, 
that's why I couldn't bear to thread through the drivel.

RC
> Both are induced in the near-field and therefore both are inductance
> coupled.  The term resonanace, just means the coupling is matched and close,
> and therefore efficient.
>
> They'd be better off talking about 'efficient induction coupling' and
> 'inefficient induction coupling'
>
>
>