Will LED-backlit LCD TVs break into mass market?

LED-backlit LCD TVs, enabled by Dolby Laboratories' High Dynamic Range (HDR) technology, produce stunningly clear pictures. Unclear, though, is how much consumers will have to pay for that kind of picture quality.

"These products have been screaming to get out to a mass market," said Eric Haruki, research director for TV markets and technologies at IDC. But he cautioned that unless LED manufacturers can achieve the economies of scale and cut the cost of LEDs, "this could still remain a great white hope for awhile."

Despite a lot of interest in LED backlight units (BLU), "the reality is that the cost is 2-2.5x that of a cold-cathode fluorescent (CCFL) BLU," traditionally used in LCD TVs, said Chris Chinnock, president of Insight Media.

The recently demonstrated Dolby/Sim2 LCD TV—using Dolby Laboratories' HDR technology—would be much costlier than this, he added.

Scalable technology
Bharath Rajagopalan, business line director of image technologies at Dolby, would not comment on the cost of HDR-enabled LCD TV. Instead, he defended it by calling its technology "perfectly scalable." He said, "You can have different performance at different cost points."

But because of the ambiguous scalability debate, the cost question lingers. "Manufacturers have never quantified how many LEDs are necessary to strike the right balance between the cost and performance in backlighting LCD TVs," said IDC's Haruki.

None in the industry has come forward to speculate on the cost of HDR-enabled SIM2's LCD TV prototype.

"That is too hard to answer and it's too early to forecast cost," said Insight Media's Chinnock. "There are so many trade-offs in performance, number of LEDs, price target point, etc. The approach shown in Dolby/SIM2 is clearly expensive, and in line with SIM2's target customers who want the latest technology."

LED manufacturers aren't disputing the cost dilemma. Willem Sillevis-Smitt, director of business management at Philips Lumileds, acknowledged that the success of LCD TVs using LED backlight depends on the cost. By cost, he means the combined cost of LEDs and driver ICs to control individual segments of LED-backlit screen for local dimming. Nonetheless, LED suppliers have reasons to be hopeful for the future of LED-backlit LC DD TVs.

Use in notebooks
The transition from CCFL to LED is already happening among LCD screens used in notebook PCs. Sillevis-Smitt said, "There is a generic belief that notebook PCs with LED-lit LCD screens will jump from the current 10 percent to 50 percent in two to three years."

NXP Semiconductors is planning to leverage the notebook LCD display technology further.

Notebook LCD screens using LEDs are lit not from the back, but from the side, by LEDs lined up along one side of the screen. NXP engineers are hoping to emulate in LCDT TVs the side-lit approach, instead of backlighting.

Such a method "keeps the flat panel screen slim," below 25mm. By using fewer LED units, it also becomes more cost-effective," said Jacques le Berre, marketing and business development director at NXP. The method, however, has some limitations. Currently, it's effective only for relatively small screens, 24-inch to 30-inch TVs. When combined with 2D dimming and new video algorithms, the LED side-lit approach may be applicable to 32-inch or even 46-inch TVs in the future, said le Berre.

Le Berre summarized "four parameters" that are essential to enable the adoption of LED backlighting for LCD TVs. They are "cost, power savings, picture quality improvement and a slimmer TV."

Product development
Philips Lumileds supplied LEDs to Sony's Qualia, the industry's first iLCD TVs using LEDs, launched in 2003.

Although Sony, soon after the launch, withdrew Qualia from the market, that hasn't dampened the appetite among consumer electronics companies for LCD TVs with LED backlighting. Richard Doherty, research director at the Envisioneering Group, said that Samsung and Sharp have already gotten on the LED bandwagon, while soon Sony and possibly LG Electronics will join.

In fact, "Every TV manufacturer in the world is working on it, and everyone has a development model in their lab," said Philips Lumileds' Sillevis-Smitt.

To take the cost out of the LED-backlit LCD TV system, the most important element is "LED's efficiency," according to Sillevis-Smitt.

Working in favor of such efficiency improvements is an emerging industry-wide trend to move display backlighting toward white LEDs instead of RGB LEDs, observed Sillevis-Smitt. The use of white LED for display backlighting "offers a much simpler and more robust solution and it lowers LED counts."

Most LEDs used in new notebook PC LCDs are already using white LEDs. The Dolby/SIM2 prototype is also using white LEDs. Looking back on 2003, Sillevis-Smitt said that Sony's Qualia LCD TV, when launched, used 450 LEDs, which consumed 450W of power. "Four years later, we can offer the same picture quality by using 120 LEDs, consuming 130W, only 1/3 of the original power."

Vizio factor
Envisioneering's Doherty sees LCD TVs using LED backlighting as "too small a market" at this point. However, he added, "This 5-10 percent of market today might be 50-60 percent of all display profits in the next year or two." This is because ordinary LCDs will bottom out, becoming loss leaders, he said. In contrast, LED-backlit LCD TVs "will fill and command premium profits."

There is also a "Vizio" factor. Many in the CE industry were shocked to learn that Vizio Inc.—a little known brand name only a few years ago—gained in the fourth quarter of 2007 the third largest flat-panel TV brand market share in the United States, after Samsung and Sony, according to iSuppli. "Five years from now, TV vendors will have to offer higher performance—such as brighter contrast ratio—to differentiate their products in demonstration." IDC's Haruki said, "After all, on a brightly lit floor at a retail store, the brightest screen always wins."

Guido Voltolina, marketing director of image technologies at Dolby, said that with HDR-enabled LCD TVs, consumers could see the difference in picture "with zero explanation." According to Voltolina, Dolby's consumer studies in Japan and the United States both showed, "More than 20 percent of consumers said that they would buy a 37-inch LCD TV with HDR technology, even with an additional cost of $1,000." More than 70 percent said that they would not trade it for a five-inch larger screen size. But once LCD TVs start to take off, even a bigger question looms: Can LED manufacturers keep up with volume production?

Question of supply
The industry has relatively few LED manufacturers. Considering annual sales of 70 million units today, if each TV starts to use more than 1,000 LED devices for backlighting, LED volume demand will soar. Scaling up production could take a while.

But Sillevis-Smitt insists that Philips Lumileds has a manufacturing platform to pull it off. The company offers high powered LEDs, called Luxeon, designed for higher output and smaller form-factor—only one quarter the size of the industry's average LED.

Philips Lumileds currently ships "millions of Luxeon LEDs," he said, "that are being used in displays in automotive, monitor and special display applications." Moreover, Luxeon Rebel, the product the company offers for display backlighting, was released over a year ago and it's been in high-volume production. Philips Lumileds has also shipped more than 100 million Luxeon LEDs used in cellphone camera flash.

"This is relevant, because it demonstrates our ability to respond to a quick and steep ramp-up scenario, and secure supply for a high-volume consumer electronics market," claimed Sillevis-Smitt.

- Junko Yoshida
EE Times