STOP FEEDING YOUR MOUSE
Cordless mice free you from the mess of wires on your desk, but they need to be fed a steady diet of batteries. Now gadget-maker A4 Tech of Taiwan has developed a cordless mouse that takes its power from the mouse mat, which is plugged into the PC鈥檚 USB port.
The plastic mouse mat is embedded with a network of hundreds of radio antennas, which induce electric currents in a coil inside the mouse, providing it with electricity. The mouse monitors the user鈥檚 clicks and scrolling, and shines an LED down onto the mat, where a pattern allows it to work out its position. Once the mouse knows where it is, it sends position and clicking information by radio signal to the mat, which in turn transmits the data to the computer.
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THE TRANSISTOR THAT鈥橲 A LASER
A transistor that generates a laser beam could lead to optical networks running at speeds of up to 100 gigabits per second through-the-air 鈥� five times faster than is possible with laser LEDs. While transistors can switch on and off faster than LEDs, until now no one had made a transistor from light-emitting materials like gallium arsenide or indium arsenide.
Now Milton Feng of the University of Illinois at Urbana-Champaign has made transistors from a blend of indium, gallium, arsenic and phosphorous, which he has tuned to emit infrared laser light that can be switched on and off at speeds in excess of 100 gigahertz. He will reveal how he did it in Applied Physics Letters.
DOUBLE TROUBLE IN GADGET LAND
The dream of a hybrid disc 鈥� a music CD on one side and a movie DVD on the other 鈥� has quickly turned sour. Just days after the first DualDiscs hit shops in the US, Sony, Philips and Pioneer are warning people not to use them.
Sony says the discs may jam in CD or DVD players and that the DVD side of a DualDisc may become scratched and unplayable. The firm鈥檚 games division has found that the discs will damage PlayStation2 consoles if the console is used in the vertical 鈥渢ower鈥� position because 鈥渢here is a greater likelihood that the DualDisc will come into contact with the mechanical parts of the console鈥�.
Pioneer recommends that people do not use DualDiscs with any of its products. Philips says DualDisc makers should print prominent warnings on packaging that playing them risks damaging both disc and player.
