Light bulbs being replaced by microchips

How many scientists does it take to change the lightbulb?

It’s not a joke. The ubiquitous lightbulb is quietly on its way to becoming as quaint a relic as the gas lanterns it replaced more than a century ago.

Barnaby J. Feder, New York Times

Incandescent bulbs, neon tubes and fluorescent lamps are starting to give way to light-emitting microchips that work longer, use less power and allow designers to use light in ways they never have before.

The chips — 18 million of them — are already on display in the $37 million Nasdaq sign in New York’s Times Square. They are in the vibrant facade of Chicago’s Goodman Theater and adorned last year’s White House Christmas tree. More notably, the chips are penetrating such blue-collar tasks as illuminating traffic lights, brake lights and exit signs.

Lighting experts expect the pace of change to pick up as researchers continue their relentless efforts to shrink the chips to microscopic size, improve on their already impressive energy efficiency and increase their brightness. The chips are expected to move into the 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.

"We are not talking about replacing lightbulbs," said Arpad Bergh, a former Bell Labs researcher who is president of an industry trade group working with the U.S. government to promote the new technology. "We are talking about a totally new lighting industry."

The vision of revolutionary new uses of light reflects the ability of such lighting, also known as solid-state lighting, to switch virtually instantaneously among more than a million shades of color at the command of a computer.

Researchers talk about using the technology to let the dramatic lighting of a movie battle scene leap off the screen and be reflected within a theater or to alter the color and brightness of lighting in nursing homes at appropriate times to help caretakers stimulate or soothe residents.

The chips, which are known as light-emitting diodes, or LEDs, have huge performance advantages in many mundane tasks. In devices like traffic lights, for example, they consume 80 percent less electricity than the bulbs they replace, and last up to 10 times as long. Moreover, they have the safety advantage of gradually fading instead of unpredictably burning out.

Beyond such obvious benefits, though, it is the ease of mating the chips to computers that is driving interest. Programs simple enough to run on a handheld personal digital assistant can alter the intensity, pattern and colors produced by solid-state lights. Color Kinetics, a 5-year-old lighting firm in Boston, calculates that the various chips it packages with computer controls can generate up to 16.7 million colors.

That flexibility is already used in advertising and entertainment. Solid- state lights are featured in numerous Times Square signs and Broadway shows like "Hairspray." Mad Doc Software, based in Lawrence, Mass., has designed tools to link video games to room lighting so that a player in a Star Trek game passing a red nebula would have one side of a room shift in color.

"It’s fantastic how much more immersive the game becomes," said Ian Davis, founder of Mad Doc.

Architects and building designers have far more ambitious possibilities in mind, including mimicking indoors the variability of natural lighting as the day progresses. Lighting experts predict that once costs come down, such flexibility will vastly increase the attention paid to the role of light in people’s moods and health.

"LEDs are only limited by what we put in the computer," said Fred Oberkircher, director of the Center for Lighting Education at Texas Christian University. "I’m waiting for the day when clouds of light float across my ceiling."

It may sound whimsical, but Oberkircher’s vision is rooted in research suggesting that people find the rigid lighting environments they normally work and dwell in boring and, in some cases, unhealthy.

While most market projections are based on comparing the progress of solid- state lights toward matching the cost and performance of traditional incandescent and fluorescent white lights, some experts say that such comparisons miss the point.

"The ability to do things you couldn’t do before is what will trigger mass adoption," said Michael Holt, president of LumiLeds, a leading diode producer that is a joint venture of Agilent and Philips. "People will become much more attuned to the mental and health aspects of light in the next five to 10 years. "

http://sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2003/04/15/BU148355.DTL&type=tech