Lighting experts expect the pace of change in developing light-emitting diodes to pick up as researchers shrink the chips to microscopic size, improve their already impressive energy efficiency and increase their brightness. The chips are expected to move into the general home and office lighting market as early as 2007.

The eventual result, the experts say, will be savings of billions of dollars annually in energy and maintenance costs and a revolution in how people use lighting in homes and offices to influence their moods.