Jeff Lieberman’s Lightbulb.

Jeff Lieberman created this light bulb that lights up while being suspended in mid air!

Lightbulb uses a special bulb, inside which magnets and circuitry are hidden. Using a magnetic hall effect sensor, an electromagnet, and a [modified] PD feedback system, it floats a lightbulb stably in the air, while power is transmitted wirelessly from the base of the sculpture into the bulb. LEDs in the bulb rectify this AC power and convert it to light. The power transfer functions very similarly to how radio station tuning works and requires a well tuned matched pair of resonant windings, but allows power transmission over through the air.

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