女生小视频

Matsushita of Japan is developing a long-life lamp that uses microwaves to
make artificial daylight. Today鈥檚 light bulbs use a white-hot filament, while
fluorescent tubes use electrodes to create a plasma鈥攂ut both kinds burn
out after a few thousand hours. Matsushita uses 2.4-gigahertz
microwaves鈥攖he same frequency used in microwave ovens鈥攖hat resonate
and excite indium and bromide compounds, radiating light. Without filaments or
electrodes to wear out, the 50-watt lamp lasts 60 000 hours. It鈥檚 not due to go
on sale until 2002, however.