
                         Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: FRIDAY, October 21, 1994                   TAG: 9410210051
SECTION: NATIONAL/INTERNATIONAL                    PAGE: A2   EDITION: METRO 
SOURCE: THE WASHINGTON POST
DATELINE: WASHINGTON                                 LENGTH: Medium

ZAPPED BULB IS BRIGHTER

The Department of Energy on Thursday unveiled what it called ``a revolutionary 21st century'' lighting system that uses a bulb of sulfur bombarded by microwaves to produce bright illumination resembling sunlight - and at a fraction of the cost of conventional systems.

The prototype lamp, invented by Fusion Lighting Inc. of Rockville, Md., under contract to DOE, consists of a closed quartz sphere filled with an inert gas and a tiny amount of sulfur. One golfball-size sulfur bulb, when irradiated by the kind of compact microwave generator found in kitchen ovens, puts out as much light as hundreds of high-intensity mercury vapor lamps.

The result is ``a major technological breakthrough in lighting,'' said Christine Ervin of DOE.

Commercial products are not expected until some time in 1995, and the first applications are likely to be used in lighting extensive outdoor and indoor spaces such as shopping centers and factories.

A test is being conducted at the National Air and Space Museum, where three 90-foot-long, 10-inch-diameter reflective plastic ``light pipe'' powered by sulfur bulbs have replaced 94 fixtures in one display area. The test units put out three times more light at a 25 percent saving in cost, Ervin said.

Also important, said Frank A. Florentine, the museum's lighting director, is that the sulfur bulb emits much less ultraviolet light than traditional devices. UV radiation ``is damaging to nearly everything'' in the exhibits, he said - notably uniforms and space suits, some of which have already had to be replaced or renovated because of damage from the existing lights.

Unlike most other high-intensity lighting sources, the sulfur lamp has no electrodes, which are ``the principal limitation to achieving long life in conventional bulbs,'' Ervin said. And because there is no evidence that the sulfur reacts chemically to degrade the quartz, the lamp may not wear out for years. ``We just don't know how long they'll last,'' said Fusion Lighting Vice President Kent Kipling.

by CNB