LED headlights, currently a technology for pricey luxury cars, are starting to enter the mass market.
By 2020, LED headlights will account for 20 percent of headlights produced worldwide -- up from roughly 2 percent this year, according to a market projection by Osram, a leading supplier of automotive lighting components.
LED taillights and daytime running lights have proved popular with automotive designers, who like to use LEDs to create intricate jewel-like looks for their vehicles.
Automakers favor LEDs because they are durable, compact and energy-efficient, but they are still relatively expensive. A no-frills halogen headlight might cost automakers $20 or so, while a xenon headlight generally ranges from $60 to $80. LED headlights cost roughly twice as much as xenon headlights, although the cost is declining fast.
LEDs, or light-emitting diodes, generate light when electricity is passed through a diode made from a silicon chip. Halogen and xenon lamps are different types of incandescent lights.
Claus Allgeier, Osram's vice president of solid-state lighting, predicts that over the next three years or so, LEDs will achieve price parity with xenon lights.
"This is a huge transition," Allgeier said in a Sept. 4 interview. Prices "have been changing quite rapidly. Over the last two or three years, there has been a substantial improvement of price and performance."
Because they do not generate light from heat, LEDs are more energy efficient than halogen bulbs. A halogen headlight might require 65 watts, while an LED headlight might need only 15 watts or so.
Toyota has shown some willingness to equip mass-market models -- such as the Prius -- with LEDs. Others seem likely to follow, given recent efforts by suppliers to design low-cost generic LEDs.
Three years ago, Osram introduced a generic LED unit, a component that looks like a small hockey puck.
Automakers can use it as a relatively inexpensive light source for taillights, headlights, brake lights or other uses.
General Motors has used it for daytime running lights on the Cadillac XTS and ATS. Ford and Mitsubishi have used it for fog lights, and BMW has used it for fog lights and headlamps.
But Osram's puck is not a one-size-fits-all solution, acknowledges David Hulick, Osram's marketing director.
"We believe there will be more opportunities" for a standardized LED headlight as automakers use that technology for mass-market cars, Hulick said. But many automotive designers are reluctant to adopt the LED "puck" because it sets some limitations on the look of the headlight or taillight.
"Lighting is used as the car's jewelry," Hulick noted. "It's used to create a brand identity at night. The challenge for the lighting industry is to serve that purpose and look for other solutions."
In the near future, the luxury segment is the strongest candidate for LED headlamps, fueled by some recent innovations.
At the Frankfurt auto show last week, Audi introduced the latest twist for LEDs: an A8 sedan equipped with an LED high beam that can dim itself without using mechanical shutters. Hella KGaA Hueck & Co. will supply the headlight, using LEDs produced by Osram.
The A8's high beam features five light bars with five LEDs per bar.
That high beam can be left on. When a camera mounted on the windshield spots an oncoming vehicle, some of the LEDs are turned off automatically, creating a gap in the high beam to avoid blinding the oncoming motorist.
And if there are two vehicles -- say, an oncoming truck plus a car that your vehicle is overtaking -- the controls can create two or three gaps in the headlamp's beam to reduce glare, says Steffen Pietzonka, marketing vice president of Hella's lighting division.
"We really think that it will be the future for high-beam headlamps, especially in the premium car segment," he said.
Osram also has teamed with Audi to develop an experimental LED headlamp that generates a high beam with the help of a matrix of 78 LEDs arrayed in three rows.
The matrix LED headlight appears practical enough for production. Osram executives recently demonstrated the headlight's effectiveness during a recent night cruise on some country roads near the company's technical center in Herbrechtingen, Germany.
To be sure, automakers already have introduced headlights that dim automatically, but those require mechanical shutters to dim the high beams. Osram and Hella have dispensed with shutters, and their LED high beams are tailored to eliminate glare more precisely to accommodate oncoming traffic.
For the moment, matrix LED headlamps are too costly for the mass market, but LED prices are declining, as Allgeier noted.
"Regardless of technology, we have been limited to 70 meters of vision for the low beam for many years," Allgeier said. "Now, that's a barrier that we can overcome."