The light-emitting diode (LED), a relative newcomer to the
century-old automotive lighting market, may finally be gaining ground on the
venerable incandescent bulb.
A new breed
of brighter, less costly, more efficient LEDs are making their way into a wide
variety of automotive applications, ranging from center high-mount stop lamps
(CHMSLs) and turn signals to vehicle cockpits and headlights. Moreover,
applications for the technology are growing in unexpected ways. The 2010 Ford
Mustang, for example, will use an LED-based feature called MyColor, which
allows drivers to customize the interior lighting of the Mustang to suit their
moods. Similarly, Kia Motors' Soul has employed LEDs in its sound-reflecting
speaker lamp (watch a video of it),
which responds with variable light to the beat of the music that's playing on
more automotive functions are using LEDs," says Viren Merchant, engineering
manager for exterior electronics at Visteon
Corp., a tier-one automotive electronics supplier. "In the beginning, its was
just CHMSLs. Now it's everything from backup lights to rear fogs to daytime
say the growing popularity of these electronic lights, which are based on
the semiconductor diode, is the result of several trends. Newer, brighter
designs are said to be about 10-20 times more powerful than the products of
five years ago. A few LED products now offer in excess of 50 lumens/W â in
some cases as much as 100 â whereas many products a few years ago offered less
than five. Meanwhile, electric vehicles and hybrids need power-efficient
lighting, which boosts the appeal of LEDs. At the same time, the cost of LEDs
has gradually dropped over the last five years.
ago, there were no LED headlights," says Richard Vaughan, design manager in the
Innovation Group for Visteon. "Today, LED headlights are optional on some
high-end cars. And as the cost continues to come down, we'll see the
proliferation of the technology in less expensive models."
To be sure,
less than 2 percent of headlights are estimated to use LED technology today. But
suppliers say that more than 80 percent of Asian cars use LED-based CHMSLs. Similarly,
more than 70 percent of European cars and about half of North American cars are employing
LED-based CHMSLs. On the exterior of the vehicle, automakers are also using
LEDs in daytime running lamps and parking lights, as well as the high- and
of increased use of LEDs in headlights, Osram
Opto Semiconductors rolled out the Ostar
Headlamp LED in November. The product is equipped with one to five
semiconductor chips, in an effort to make it usable in a variety of different
headlamp sizes and shapes. Depending upon the number of chips used, the unit
produces from 1 to 25 lumens at 700 mA (one chip) to 1,000 lumens at 1 A (five
suppliers say the design flexibility of the LED is a key to its growing
popularity. LED packages can be altered to incorporate different numbers of
chips, as well as different shapes and sizes. Automakers such as Cadillac, for example, have used that
flexibility to create unusually shaped CHMSLs and tail lamps.
"It's a way
to communicate to the consumer," Vaughan
says. "Designers can achieve the shapes and length patterns that consumers can
see and identify."
sense, LEDs are helping automakers create greater brand awareness, in the
interior, as well as the car's exterior. Osram, for example, has rolled out
LEDs of various colors â including ice blue, blue lagoon, sky blue and blue
green â which enable automakers to tune the interior color to match their
brand. In an even bolder step, Ford is
employing the technology in MyColor, a system that allows drivers to change the
interior colors to match their moods.
not only the instrument cluster, but the whole ambience of car," says Mike
Godwin, director of visible LED products for Osram Opto Semiconductors.
Godwin says, is to use LED technology to enhance a car model's image. "They use
the idea of color-on-demand to create a brand color," he says. "Their cockpit
or their cupholder can illuminate in whatever way they want."
suppliers and LED makers alike say that LED adoption in automotive interiors is
growing fastest of all. "Every interior request for a quote we've received from
every manufacturer around the world the last two years has had some aspect of
LED ambient lighting to it," Vaughan
expected proliferation of hybrids and electric vehicles, LED use is expected to
grow faster still over the next decade. On those vehicles, where power is at a
premium, engineers are more likely to disregard cost differences and reach for
LED technology. "It saves about 400-430 Watts of power across the interior of
the vehicle, and about 20 Watts on the interior," Godwin says.
At the same
time, engineers who want more brightness per W are getting that, too. In
April, Philips Lumileds rolled out the Luxeon Rebel
ES, said to be the world's first high-efficacy power LED specified to
deliver a minimum of 100 Lumens per W. The new product joins earlier
Lumileds entries that offered 30, 42 and 50 lumens. The new breed of brighter
products is expected to take LEDs into exterior applications, such as red stop
lamps, where they've been used sparingly before.
ago, a red LED was one to five lumens," Merchant says. "Today, you can easily
get mid-20s in a red LED."
most of the success of LEDs is being realized in luxury- and mid-level
vehicles, engineers say. Cadillac's Escalade, as well as selected Lexus and
Audi vehicles, are employing LEDs across the board in high-beam, low-beam,
daytime running lamps and parking lights. But as prices continue to drop and
automakers move to more energy-efficient vehicles, LEDs are expected to migrate
toward entry-level cars.
aren't going away in the foreseeable future," says Merchant of Visteon. "But we
do know that LEDs are here to stay."