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A lightbulb powered by radio waves

Forget that electrode splatter. To make light, you need RF and a special designed cavity.

Most lightbulbs create light with a pair electrodes. Luxim does it with radio waves.

The Sunnyvale, Calif.-based start-up has come up with a way to get rid of the parts inside of high intensity discharge (HID) lamps that are often the first to fail. As a result, Luxim's LiFi (light fidelity) lamp provides more lumens per watt and lasts longer than competing products, according to the company.

Your fancy lightbulb, sir. luxim

In traditional HID lamps, high voltage pulses pass between two electrodes. The energy creates plasma from the ambient gases trapped inside the bulb and you get light. The electrodes, however, degrade over time. Tungsten splatters off of them and blackens the surface of the bulb.

By contrast, the Luxim bulb doesn't have electrodes. Instead, a radio frequency amplifier pumps RF waves to an antenna inside a resonant cavity. The interaction between the waves and the crystal cavity convert trapped gases into a plasma.

"The structure creates a concentrated electrical field in response to a standing wave," explains Julian Carey, vice president of sales at Luxim. "It creates a plasma inside a quartz capsule."

Luxim's bulbs get 120 lumens per watt, thus making them more energy efficient. By contrast, many HIDs only get 90 lumens per watt. (Top-end LEDs crank out around 70 lumens per watt). Light sources are big with investors these days.

Panasonic has inserted Luxim's bulb into projection TVs. It can also be used in projectors. Investors include Crosslink Capital and Sequoia Capital.

"It has a 5X lifetime" in projectors over regular bulbs, Carey said. "The lifetime of the light source is as long as the projector itself."

Radio waves are part of the electromagnetic spectrum (so says the Harvard grad at the desk next door) like visible light and microwaves. But they have a different wavelength.