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A Tablecloth to Charge Your Laptop
moscowde writes "Research scientists at the University of Tokyo have come up with a unique sheet-like material that can transmit electrical energy over a large area to nearby devices without the need for direct contact, so it can be made into a tablecloth or wallpaper and your appliance can be anywhere on a surface to get charged.
The system uses organic molecules as transistors, microelectromechanical switches, and miniature copper coils to transmit energy using electromagnetic induction."
If this could help get rid of the mess of power plugs and cables under my desk, this would be utterly fantastic. Wonder what happens if a liquid is spilled on the surface though...
I'm sure there's nothing harful in wrapping ourselves in yet more electromagnetic fields, not even shielded ones in this case.
I mean, what could possibly go wrong? After all little Jimmy's third arm is quite handy.
My soup has electrocuted a fly!
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
It sounds like magnetic induction -- same thing they use to charge electric toothbrushes without exposing any wiring to water and toothpaste. It should work just fine with water.
My questions on this would be more focused on how practical it'll actually be, unless it's standardised so that different devices can charge off it, and on how wasteful it is, if it's throwing out energy even when nothing needs it.
One of the intriguing Nichlai (sp?) Tesla did in his lab was to place an inductive ring just below the cieling like crown molding. Then he had electric motors powered by inductive coupling. Instead of "plugging" in the device to the wall socket, all he has to do was to raise a ring the ceiling. To "unplug", lower the ring by a few inches. Will try to find some references and post it soon.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Grampa if you don't get me a pony and take me to the zoo, I'm going to recharge my ipod! Then you'll be sorry!
At certain frequencies I can actually feel the EM field as a slight tingling in my skin. My Wacom tablet does it but my hand has to be pretty close to it to feel anything (which is really annoying because I otherwise love that tablet).
If I were you I'd be experimenting with that tablet using my own fleshy stylus. Assuming you have one.
I dunno, after seeing my friends wrestle with BT all the time [hidd --search, over and over] I'm actually fond of wired devices. Sure I use wifi from time to time but I'd generally much rather cat-5. No hassling with "do I have a good signal" and all that jazz.
Sometimes it's nice to just plug something in and have it work without worrying about the environment.
And sure a power "pad" sounds nice but take into account the power loss. The thing most likely converts AC to DC [power loss], then from DC to EM [power loss], from EM to DC in the device [power loss]. So you'll be burning more energy to get the same amount of work done. Not exactly a step forwards.
Tom
Someday, I'll have a real sig.
I cannot find any reference, however I recall reading an article several years ago which detailed a consumer deskpad which contained dozens of micro contacts. The idea was you simply lay your laptop, mobile phone, pda on the pad, and it begins to charge. Of course this product assumed that your devices were outfitted to use the charger. A microcontroller would actively sense the current between pad contacts, allowing charging, but preventing short circuits. Again, as I cannot locate this product now, I expect it did not take off.
Inductive charging also seems inefficient to me. The article claims 80% efficiency. What exactly do they mean? How many AC-DC conversions take place within this charger?
Also, my laptops require more like 80w. It may be okay for PDAs and mobile phones.
IMO, a good research project, but not yet near a consumer product.
In original research paper published in "Nature Materials" there is a picture of a fish tank with fish inside. The light inside the tank is powered using this transmitting material. Power cables, sockets, and plugs are not required, and all of the metallic parts are coated with insulating materials. So it is safe.
Lord Armstrong, a Victorian inventor and armaments manufacturer had one of, if not the first, electrically lit house in the work. Cragside" was lit (initially by carbon arc lamps but then by Joseph Swan's incandescent light bulbs) powered by hydroelectric power. During the day horses pumped water to a lake up the hill side. During the night that water generated electricity.
The table lamps replicated old oil lamps in style but had spikes which poked in to table clothes which were threaded with copper wire carrying current. This meant you could carry them around, put them down, and they would just light.
How efficient is it? In these days of global warming the last thing we should be thinking is replacing all those chargers which are left plugged in 24/7 with something that's even less efficient...
No sig today...
There's no better way to teach kids about keeping their elbows off the table.
Right?
BRRRZZZTTTT!! RIGHT!