By JOHN D. ORAVECZ
Pittsburgh Tribune-Review
PITTSBURGH (AP) _ A carbon-based molecule that looks like colored sugar could bring big changes to big-screen TVs.
Organic light-emitting diodes, or OLEDs, manufactured by PPG Industries Inc. of Pittsburgh, could give televisions more vibrant colors and deeper blacks, make them thinner and lighter in weight, and most importantly, much more energy efficient. The industry is working to speed development and cut production costs for the display technology.
Experts say consumers would benefit when TVs utilizing the technology become more affordable.
A limited production, 55-inch OLED model by Samsung Electronics listed at $13,000 when introduced a year ago now sells on the Internet as low as $5,849. But mature big-screen technologies _ plasma and LCDs _ cost a third to a fourth as much.
Organic LED televisions hold the best promise for manufacturers to recapture a market that has declined since 2011, despite 3-D, curved screens and higher resolution. Organic LED displays would combine the best attributes of plasma and LCD screens with none of their shortcomings, says Consumer Reports.
Samsung “is the best TV we’ve ever seen,” Consumer Reports said in a recent issue. “But it will be some time before prices drop to mainstream levels.”
PPG makes the crystals at plants in Monroeville and Barberton, Ohio, and ships them to its partner, Universal Display Corp. of Ewing, N.J., which controls the patents on advanced phosphorescent organic LEDs _ four times more energy efficient than other types, experts say.
These carbon-based molecules are unlike metallic LEDs commonly used in light bulbs.
“Universal Display designs the materials, and then we scale those up and manufacture them,” said Carol Bateman, business director for organic LEDs for PPG.
PPG ships the crystals in small vials to Universal Display, which sells them to Samsung, LG Electronics and others, who are working on how best to apply OLEDs onto glass and plastic.
“A little bit goes a long way,” said Bateman. One gram can make 300 to 400 smartphone screens, depending on size.
OLEDs are used in cellphones and mobile devices, most notably Samsung’s recently introduced Galaxy S5 smartphone. Google and LG recently introduced smart watches and bracelets. Lighting is a potential high-growth market, once technical obstacles are overcome.
“All of the components, materials and fabrication costs have to come down, and that’s what we’re trying to do,” said Mehran Arbab, director of glass science and technology at PPG’s Glass Business and Discovery Center in Cheswick. That would help Samsung, LG, Sony and others make displays at lower prices “so they become popular and you can buy them at Home Depot or Costco.”
Difficulties with making small devices underscore the more complex challenges manufacturers face in producing big-screen TVs using OLEDs, said Janice Mahon, vice president of technology commercialization at Universal Display.
“One square meter of glass can make 100 cellphone displays or one large TV display,” said Mahon. “If one cellphone display has a defect, you can throw that one away and still have the rest. If you have the same defect on the TV, you have to throw away the entire display.
“The need to improve yields in manufacturing, or decrease defects, is much more demanding as one moves to larger displays.”
When color television debuted in the 1960s, picture tubes made color by electronically combined light from red, green and blue pixels. Today’s dominant big-screen TVs use liquid crystals to switch a source of light on or off behind pixels.
In OLED displays, “blue is the weak link, from a life and energy-efficiency perspective,” said Mahon. “It’s a high priority to develop deep, long-lived blue OLEDs to complete our suite of colors.” Red and green OLEDs are rated to last more than 20 years, but blue lasts only about four years.
Blue OLEDs used in smartphones and other devices are fluorescent OLEDs, a different type that aren’t as efficient, Mahon said, and are made by a half-dozen companies, such as Dupont and Idemitsu Kosan of Japan.
“Bringing a strong blue phosphorescent OLED to market is important. But to bring costs down, yields must increase,” she said. “It’s more a manufacturing challenge than a blue challenge.”
The advantage to organic LEDs is that they emit light directly when electricity is applied and don’t require a backlight. That allows thin, flexible displays.
“It’s almost limitless what you could do with flexible electronics,” Bateman said.
PPG used expertise gained from its development of eyeglass-darkening technology for plastic lens. Starting in 1990, PPG built that business into Transitions Optical, which markets eyewear with a coating _ called photochromics, developed in the Monroeville plant _ that darkens in bright sunlight.
Last month, PPG sold its share of Transitions Optical to its partner Essilor International for $1.73 billion.
PPG hopes OLEDs will pay off down the road. A significant share of $63.1 million that Universal Display spent last year on OLED materials and research went to PPG, Mahon said, though she would not specify.
“We were in that business when Universal Display came knocking. We were able to apply that expertise to organic LEDs, and we’re hoping that this work will create the next spin-off application for OLEDs,” Bateman said.
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