Teaching plasma to follow LCD's lead

The energy-hog televisions are losing ground to their cheaper counterparts. But developers hope that will change with improved technologies.

Once considered the future of television, plasma TVs have lost their shine.

In the last several years, the display known for excellent picture quality has given ground to the exploding popularity of LCD (liquid crystal display) in the high-definition TV market. Though plasma TVs were first to reach consumers a decade ago, LCD TV manufacturers were able to bring the costs below their plasma counterparts with an efficient panel manufacturing process.

Now researchers are looking at ways to improve plasma's brightness levels, power consumption and cost, and developers hope that will help plasma regain some of the ground it's lost. Of course, LCD technology will also improve, but the closer pricing appears between the two, the more viable an alternative plasma becomes.

"Performance will be going up in both (plasma and LCD), but costs will be coming down faster in plasma," according to Ross Young, president of market research firm DisplaySearch.

That's good news for consumers. One of the biggest challenges in getting people to switch to high-definition TVs is the price. Predictably, as prices have fallen in the last year, more consumers are willing to buy into the idea of the HD experience. About 1 million plasma and 5.2 million LCD TV sets were sold in the U.S. last year, compared to about 750,000 plasma and 2.6 million LCD the year before that, according to retail tracking data collected by The NPD Group.

"Plasma panels will perform better in all environments, and at the same time, they'll get cheaper--that's a pretty nice advance for plasma."
--Ross Young, president, DisplaySearch

LCD is so far the undisputed champion of the HDTV popularity contest, and much of it has to do with price and manufacturers' ability to scale the technology to increasingly larger screen sizes. But plasma manufacturers have gradually found ways to produce their displays for less too. The average price of an LCD dropped from $989 last year to $932 this year, while plasma's average price fell from $2,480 to $1,664.

Besides lower price, one of the traditional benefits of LCD over plasma is the brightness of the picture in a well-lighted environment. And though all TVs can be energy hogs, plasma sets are notorious for their high power consumption.

Many believe the key to solving all three issues for plasma is something called luminous efficiency, or the ratio of the light output compared with the power input. Currently, the best plasma TVs are capable of 2 to 2.5 lumens per watt. For comparison's sake, the average fluorescent light bulb can output 80 lumens per watt.

Efficiency can be increased in several ways, including changing the concentration of the gas mixture within the plasma panel, altering the structure of the plasma cells, and using different phosphors. Companies like Panasonic, Hitachi and Pioneer have banded together to create a display capable of 5 lumens per watt, double what's currently available on the market. Simply doubling the current luminous efficiency results in twice the brightness at the existing power levels, or half the power necessary to produce the existing brightness levels.

One of plasma's most loyal proponents, plasma researcher and pioneer Larry Weber, says that if a fluorescent lamp can do 80 lumens per watt, there is "no reason a plasma display can't get anywhere close to that." Weber is currently tinkering with plasma display panels for this exact reason, although he cautions that 80 or even 40 lumens per watt could be far off. "If you ask someone today (how to double or triple the luminous efficiency) they'll say, 'I don't know how to do it right now,' but as time goes on, these things will become more likely."

Huge payoffs likely
Plasma manufacturers are trying to avoid being edged out of the HDTV market by LCD, so putting any money into research in this area will likely bring a huge payoff for them. For one, better luminous efficiency will mean fewer parts needed to put the TV together. The power supply in a 42-inch 720p plasma TV accounts for 9 percent of the manufacturing cost, for example. It's only 3 percent of the cost of a comparable LCD TV. By increasing a plasma's efficiency to 5 lumens per watt, the cost of producing the TV could become equivalent to LCD, Young argues, which will allow plasma manufacturers to simply focus on improving the panel technology. And every dollar counts in the TV market, where margins are razor thin.

The improvements are not just internal. Customers will likely notice the enhancements in picture quality as well. Right now, plasma TVs look better in dark, home-theater-like environments because of their great contrast ratio and ability to light individual pixels, but that doesn't necessarily translate well to the show floor of a big-box electronics store. Increasing the brightness will erase that difference between plasma and LCD, according to DisplaySearch's Young.

"Plasma panels will perform better in all environments, and at the same time, they'll get cheaper--that's a pretty nice advance for plasma," Young said. "Currently, people position LCD versus plasma (sales) based on where it's going to be: in a bright room with a lot of windows or a darker room or if you just watch TV at night. In the future, they both become great for all applications."

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