L.E.D. lighting has become the lighting industry's new Next Big Thing, with industry proponents predicting that it will eventually knock compact fluorescent lights off their perch as viable alternatives to standard incandescent bulbs.
But there is another application that industry observers think L.E.D.'s will also come to dominate: television displays. In a new research report from Insight Media, a flat panel research firm, the company is predicting that by 2011, cost reductions will spur a switch to L.E.D. illumination for L.C.D. TVs.
Today, rear-projection TVs typically use bulbs to illuminate their screens, which dim over time and need to be replaced. L.C.D. TVs usually use cold compact cathode fluorescent lamps (C.C.F.L.), which limit color rendition.
L.E.D.'s, on the other hand, provide a wider range of colors, do not need to be replaced, use less power,and do not contain polluting mercury, as do C.C.F.L.'s.
But using L.E.D. as a lighting source for TVs has its own problems. Many of the current L.E.D.-lit displays use up to 10,000 L.E.D.'s mounted as a grid on the back. If 100 or so are defective, it could affect light output. Plus, it adds to the set's bulk.
The image shows the small number of L.E.D. lights needed with Luminus' approach to lighting an L.C.D. TV.Luminus, a Massachusetts solid state lighting company, thinks it has the solution. The company has created much brighter L.E.D.'s, which allow it to mount just 24 L.E.D.'s on one or two sides of the display's perimeter, and then use a plastic panel to distribute the light. The fewer the number, the lower the cost. And according to Alexei Erchak, the company's founder, L.C.D. TVs can potentially be made thinner than today's sets using his "edge-lit" approach.
Mr. Erchak says that he will begin supplying L.E.D.'s to some of the major television manufacturers later this year, with products in the marketplace by early 2009.
And according to Insight Media, the cost of L.E.D. light sources for TVs will soon drop like a stone. Today, C.C.F.L.s cost about $188, with L.E.D.'s at $290. But by 2011, L.E.D. will have closed the gap; the price of a C.C.F.L. unit will drop to $121, but a typical L.E.D. unit will only cost $136.
These potential improvements prove the point made in the late 1990s by Joseph Flaherty, a CBS executive and one of the pioneers of HDTV, when he famously said "Today's HDTV images are the worst HDTV we'll ever see."
By Eric A. Taub