3 ms·
It could still be useful if it could charge your phone/laptop all the time without you needing to worry about or manage it. And in that case it doesn't need to
by rhinoceraptor 9y ago
It could still be useful if it could charge your phone/laptop all the time without you needing to worry about or manage it. And in that case it doesn't need to be as efficient as a wire since it can start charging as soon as you get home until you leave.
- jacquesm 9y ago> It could still be useful if it could charge your phone/laptop all the time without you needing to worry about or manage it. And without you using it. As soon as you start using it you'll be back to normal, and likely there would not be enough power to put a meaningful charge into anything the size of a laptop with this system. Unless phones are going to use a small fraction of the power they use today I don't see this working in practical setups. > And in that case it doesn't need to be as efficient as a wire since it can start charging as soon as you get home until you leave. 10 seconds plugged in to a wire would give you more juice than an hour or two hooked up to those transducer arrays.
- dsr_ 9y agoNobody has yet mentioned, perhaps because it's obvious: every time you change the density of the medium in the path of the sound beam, you get reflection or refraction losses. Hands are much denser than air. Not only does UBeam need to track where the receiver is, they need to hit the target without going through your hand or body to avoid another large efficiency loss -- I believe the typical figure for air/soft tissue boundaries is 99%.