~e; A totally new LED industry
Tue, 11 Feb 2003 20:38:21 -0600
// LEDs have been getting a lot of press it seems. This article is
// especially good at describing these changes (i.e. 'a totally new
// lighting industry'). Yet, I am caught up on the description of these
// Light-Emitting-Diodes as 'chips', as in 'microchips'. I do not relate
// to how a diode can be a considered a chip. If anyone knows, please
// share. Maybe the materials are baked on a chip, made a semi-
// conductor plants, etc. As far as I know, a current goes in one end
// of the diode, crosses a material which glows, and goes out the other
// wire. The description of an LED light as a chip makes one think it
// some processing power of a programmable device, when all of this
// stuff is done remotely via computers (I am guessing, based on
// of electronic scoreboards, animated displays, and the like). In any
// I think this idea of a chip is inaccurate, yet the story is very
A Glimpse of a Future in a New Kind of Light
February 11, 2003
By BARNABY J. FEDER
How many scientists does it take to change the light bulb?
It's not a joke. The ubiquitous light bulb is quietly on
its way to becoming as quaint a relic as the gas lanterns
it replaced more than a century ago. 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
The chips - 18 million of them - are already on display in
the $37 million Nasdaq sign in Times Square. They are in
the vibrant facade of the Goodman Theater in Chicago and
adorned last year's White House Christmas tree. More
notable, the chips are penetrating blue-collar tasks like
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 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.
"We are not talking about replacing light bulbs," said
Arpad Bergh, a former Bell Labs researcher who is president
of an industry trade group working with the 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
coordinate lighting effects in a theater with film scenes,
which might make a battle sequence appear to leap off the
screen, or to alter the color and brightness of lighting in
nursing homes at appropriate times, which could help
stimulate or soothe residents.
The chips, which are known as light-emitting diodes, or
L.E.D.'s, have huge performance advantages in many mundane
tasks. In devices like traffic lights, for example, they
consume 80 percent less electricity than do 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 hand-held personal
digital assistant can alter the intensity, pattern and
colors produced by solid-state lights. Color Kinetics, a
five-year-old lighting company based 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 who is 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 greatly increase the attention paid to the
role of light in people's moods and health.
"L.E.D.'s 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 Mr. 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 assessing 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 Technologies and Philips Lighting.
"People will become much more attuned to the mental and
health aspects of light in the next 5 to 10 years."
The chips driving the revolution currently cost too much to
use in general lighting. The cost of white-light diodes for
standard electrical sockets is anywhere from 40 to 100
times that of comparably bright incandescent bulbs,
according to various industry estimates.
But like their cousins the microprocessors, the diode chips
are continually improving in performance and plunging in
price. They could become cheap and luminous enough to break
into the general lighting market as early as 2007,
according to a technology road map developed by the
Optoelectronics Industry Development Association, the trade
group Mr. Bergh heads.
By then, the chips are likely to be facing competition in
many specialty applications from a newer form of
solid-state lighting known as organic light-emitting
diodes, or O.L.E.D's. These light-emitting plastics are not
nearly as bright or durable as the chips but may prove to
be more economic for many uses. Like other polymers, they
would be manufactured in continuous processes instead of
batch by batch the way microchips are made. They are
already being used to light small displays, like the
battery-life monitor in the Norelco Spectra razor.
Whatever the progress, experts like Mr. Holt and Charles A.
Becker, head of the L.E.D. for lighting project at General
Electric's research laboratory, say incandescent bulbs are
likely to remain so cheap that they will be widely used for
years to come as white-light sources, even though they are
quite inefficient and fragile.
Light bulbs, which lighting experts deride as heaters that
happen to give off visible light, work by forcing
electricity through a metal filament in a vacuum. About 6
percent of the energy ends up as light. Today's light chips
are up to five times as efficient.
Researchers say that further development could double the
chips' efficiency advantage. If achievable, these gains
would allow solid-state lighting to surpass the efficiency
of fluorescent lamps.
The first practical diode, which emitted low intensity red
light, was invented in 1962 at General Electric. Red and
amber L.E.D.'s came to market in the 1970's as on-off
signals and other indicators for electronics and machinery.
Using diodes for general lighting seemed laughable until
researchers at companies like Cree, Nichia Chemical,
Toshiba and Hewlett-Packard discovered much brighter
materials and relatively inexpensive emitters of blue and
green light in the early 1990's.
Blue diodes were crucial to generating white light, which
could be produced by blending the blue, red and green or by
shining the blue light through a coating of yellow
phosphor. By last year, products built around the new
generation of higher-intensity colors and white light had
become a $1.2 billion market, according to Dr. Robert V.
Steele, director of optoelectronics research at Strategies
Unlimited, a market research company in Mountain View,
The biggest market at the moment is in outdoor signs and in
lighting the contours of buildings like fast food
restaurants, where the diodes are displacing neon. The
nation's four million or so traffic signals represent a
smaller market, but diodes have taken over a third of it
and continue to spread rapidly, according to Gary R.
Durgin, vice president for business development for
Dialight, a solid-state lighting supplier based in
Buses, trucks and autos have diodes in brake lights and
interior lighting. Styling and maintenance benefits are
driving the trend, but there are safety benefits, too.
Because the diodes light up fractions of a second faster
than do incandescent lights when a driver hits the brakes,
anyone trailing a vehicle at 65 miles an hour is able to
stop about 19 feet sooner, according to a study at the
University of Michigan Transportation Research Institute.
New research fields like nanotechnology are spurring
innovation. In July, for instance, Kopin, a manufacturer of
semiconductors and electronics displays based in Taunton,
Mass., disclosed that it had discovered a way to make
millions of pockets just two nanometers thick - the width
of just 10 hydrogen atoms - in the dust-size light-emitting
chips. The nanopockets, as Kopin calls them, help light
escape the chip without being obstructed by microscopic
defects in the chip's crystal structure. The new design cut
the voltage needed to get light out of the chips enough to
grab the attention of makers of battery-operated
As a result, Kopin, which was once unknown in the industry,
is gearing up to ship 100 million light chips this year to
contractors who will package them with power and optical
components for use by device manufacturers.
The first applications, according to John Fan, Kopin's
chief executive, are likely to be back-lighting for
liquid-crystal displays on portable electronics and
night-lighting for keys on devices like cellphones. The
chips are so small that the entire year's production could
be easily enclosed in a golf ball.
Mr. Fan and other entrepreneurs have been attracted by the
potentially huge environmental and energy returns from
replacing traditional lights with solid-state devices. One
widely cited study for the Energy Department concluded that
the widespread use of solid-state lighting by 2025 could
cut electricity demand 10 percent and save consumers $100
Getting there is not a trivial challenge, though.
Researchers say there are numerous hurdles to overcome in
fields like manufacturing technology, chip design and
extraction of the light created in the chips.
The new technology also requires changes in regulations and
standards. For instance, the advertised life of a product
line of light bulbs is set as the length of time until half
of them fail in tests. But solid-state lighting slowly
degrades rather than burning out so the industry is
struggling to come up with an agreed standard for "useful
While many in the industry are confident about where their
markets will end up, the hurdles make it hard to project
how they will get there.
"It's easier to know what will happen 10 years from now
than 2," said Mr. Durgin of Dialight.
Copyright 2002 The New York Times Company
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