Fluorescent lights are commonplace mysteries-the physics of the
interaction of electrodes, electric field, and the photon-emitting plasma they
produce isn't completely understood. It is known that efficiency improves with
increasing distance between electrodes. Thus, the most efficient bulb would have
infinite distance between electrodes. In effect, it would be "electrodeless."
Enter the Genura lamp from GE Lighting, Cleveland, OH. Although the electrodeless design was patented in 1970, it's taken a quarter century for the necessary power-conversion electronics to shrink to the point where the bulb can fit into conventional incandescent cans. The bulb produces as much light as a 75-W incandescent but uses only 23 W and has a rated life of 10,000 hrs. On sale now in Europe (where, due to the higher supply voltage, the efficiency is even higher), Genura will debut in the U.S. this spring for commercial and industrial use.
Phosphor coating on the bulb's inner surface converts UV photons from energized plasma into 1,100-lumens of 3,000K-color, visible light.
Electron/ion plasma results from interaction of high-frequency electromagnetic field with a proprietary bulb-gas mixture.
Induction Coil resides completely outside the pinched-sphere-shaped bulb, generates electromagnetic field. The bulb itself comes from a GE Lighting plant in Nagykanizsa, Hungary. The glass-blowing technology is reputedly among the world's best.
VALOX(R) housing from GE Plastics supports and protects two-piece bulb, serves as chassis for electronic and Edison-base power connector.
Electronics package converts service-line electricity to 2.65-MHz power for induction coil. Its compact circuits were designed concurrently by GE Lighting operations in the U.S. and U.K. as well as engineers from the GE R&D Center, Schenectady, NY.