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Mouse Uses RFID Instead of Batteries

Posted by Zonk on from the bluetooth-concept-replacement dept.

ValourX writes "NewsForge (part of OSTG, like Slashdot) has a review of a mouse that is powered by RFID (and yes, it works with Linux). It's cordless and uses no batteries -- you just have to keep the mouse within 2 inches of the mousepad for it to work. What else could be powered by RFID?"

4 of 208 comments (clear)

  1. You're kidding, right? by Short+Circuit · · Score: 5, Informative

    One, it's not RFID. RFID is a means of identifying things, that happens to use the RF from the detector as a power source. You can use RF as a power source without it being RFID.

    Two, bateryless cordless mice are old news. I've got a Graphire 2 next to me that's done that thing for three or four years.

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    tasks(723) drafts(105) languages(484) examples(29106)
  2. Re:More Like: Inductive Coupling by david.given · · Score: 4, Informative
    ...but more power wasted by beaming it into the air across a 6"x8" area.

    No power is wasted. This is actually an induction antenna; think of it as a transformer where one coil is in the mouse pad and the other is in the mouse. If there's nothing to pick up the power, no current flows (or at least, very little). The technique is used all over the place.

    The only thing I'm wondering about is what happens about stray bits of metal placed on the mouse mat. If you're not careful, power will get transmitted to them; not only does this waste energy, it can be potentially dangerous... you wouldn't want to discover your wedding ring getting hot after using the mouse for a short while...

  3. Way back when, or something old something new by Senor_Programmer · · Score: 4, Informative

    Back in the day the KGB beamed microwaves at the US embassy to power bugs for spying.
    The simplest bug I know of is antenna, half wave rectifier, carbon microphone. As the load varies (carbon mike changes resistance with sound pressure) the amplitude of a harmonic is modulated and radiated by the same antenna.

  4. These have been around for a long time by typical · · Score: 5, Informative

    (a) This has nothing to do with RFID, as the parent stated.

    (b) Mice powered by induction from a special mousepad (or top-of-the-mousepad) have been around for a very long time. Presumably these didn't catch on for the same reason that optical mice that required a mousepad with a grid didn't catch on -- people don't like being forced to have a particular mousepad.

    (c) Tesla owns your ass, mouse-people -- he powered lamps with remotely transmitted power twenty-five miles away.

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    Any program relying on (nontrivial) preemptive multithreading will be buggy.