
UBeam Declassifies Secrets to Try to Prove Wireless Power Is Possible - LukeB_UK
http://techcrunch.com/2015/11/07/wireless-power-charger/
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lifeformed
It says it operates at 45kHz-75kHz. That's within hearing range for dogs and
cats, and it's pretty high power. I wonder if it's safe for them? Or at least,
not super annoying?

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lvs
In high frequency focused ultrasound therapy, transient cavitation occurs in
the kW/m^2 range, which is associated with tissue heating and damage. This is
useful for various surgical techniques and tumor ablation. For instance, it
takes 1 - 3 seconds to heat tissue to 70C with 1 kW/cm^2 [1]. Therapeutic
ultrasound (for tissue hyperthermia) is performed in the 0.5 - 3 W/cm^2 range,
and surgical ultrasound is typically above 10 W/cm^2. [2] It appears they've
set the top end of their power delivery at just below the therapeutic range.

[1]
[http://link.springer.com/article/10.1134/1.1591291#page-1](http://link.springer.com/article/10.1134/1.1591291#page-1)

[2]
[http://onlinelibrary.wiley.com/doi/10.1002/med.10004/pdf](http://onlinelibrary.wiley.com/doi/10.1002/med.10004/pdf)

