Taking another look at plasma technology? Curious about its endurance in a marketplace seemingly dominated by LCDs? Information Display talked with plasma-pioneer Larry Weber about price, lifetime, contrast ratio, the new Energy Star standard, consumer confusion, and more to find out about the many advantages of plasma TVs and the reasons for their longevity.
Interviews compiled by Jenny Donelan
LARRY F. WEBER is widely considered the founding father of commercial plasma television. At the University of Illinois at Urbana-Champaign, Weber studied under Donald Bitzer and Gene Slottow, who invented the first plasma-display prototype. Weber received his B.S., M.S., and Ph.D. degrees in electrical engineering from the University of Illinois and became a research associate professor there before going on to co-found Plasmaco, Inc., in 1987. In 2000, Weber received the Society for Information Display's Karl Ferdinand Braun Prize, "for pioneering contributions to plasma-display-panel technology and its commercialization."
Q: What are the advantages to plasma for home entertainment?
A: What I tell people about plasma is that you're going to get the highest quality image for the lowest price. It excels not only in response time but in high contrast ratio, particularly in a dark environment. That contrast is important when you're watching a dark movie at night in your living room.
Q: Has plasma found new life in part because of 3-D?
A: Being fast [capable of very-high-speed frame rates and fast pixel response times] is important for 3-D, and plasma is fast. It clearly does look better than LCDs in 3-D. But how important is 3-D? I don't know; it's hard to tell at this point.
Q: You've championed plasma most of your life, but LCD TVs dominate the market. How does plasma really compare to liquid crystal?
A: I have LCD TVs in my house, and I believe there are environments where LCDs really fit and do better than plasma. When people ask me about buying an LCD TV or a plasma TV, the first thing I ask is how bright is the room? If the room where you are going to be using the TV is really bright – the sunroom or the kitchen – you definitely want an LCD TV because plasma reflects the ambient light, just like a CRT does. It's one of the weaknesses of plasma.
Low ambient is where the plasma really shines because you can turn those pixels virtually all the way off. The LCD, on the other hand, has a very bright backlight; typically 20 times brighter than the peak luminance of the display, and so it is a challenge for the closed LCD shutter to completely block the backlight. When the LCD is used in a dark screen (which you do not see very often in store show rooms), the corners will often be brighter. This is because the sets are frequently built using edge-lit LEDs (light-emitting diodes). Very few TVs use the full array of LEDs on the back because you need a lot of LEDs to do that [and it increases the price]. With the edge-lit configuration, LED light comes from both the horizontal and the vertical edges of the display, which creates visibly more light in the corners. The plasma just doesn't have that; the light is generated from each individual pixel, so it is emitted uniformly across the entire screen.
It's also important to consider contrast ratios. What contrast ratio can you get at different viewing angles? Whenever manufacturers quote contrast for LCDs, they are measuring it straight on, and it's best straight on. If you go off-axis very much, the imagery starts to degrade, and you'll see dark blacks that look like grays along with visible color shifts. With plasma, the color and contrast ratio doesn't change with direction. So, the off-axis viewing angle of an LCD doesn't match the plasma, or its color imagery.
Also, many people like the plasma because it has a softer, more natural look – a bit like the CRT that we are used to. The LCD has a harsher look, but some people like the super-sharp kinds of images that the LCD creates. It's all a matter of preference.
One relatively unbiased group that tells a story about LCDs and plasma is the movie industry – the people who work in post-editing. These guys are perfectionists. They want the best image possible when editing film. What's happening now in this industry is that the CRTs they've used are aging and can't be replaced. The movie-industry editors aren't moving to LCDs; they are using plasma. They consider LCDs insufficient due to the contrast and color change with viewing angle. Of course, these guys are looking for little nits. They need to find every last little error and get rid of it and for that they need a panel that will be able to perform by giving them the highest-quality image.
What the LCD does have is wonderful marketing. Consider those "LED TVs," for example. Of course, these are LED backlights in an LCD TV, but many people out there buying these sets think they're a completely new technology – "LED TVs."
So the distinct advantages of plasma are its contrast ratio, its viewing angle, its consistent color coordinates, and the speed of the imagery. These are all very important issues for the home user, but the last one I should mention is price. The price of plasma is lower than that for an LCD.
Last year, plasma sold 19 million sets worldwide; it actually took market share from LCDs. How do most people buy TVs? They get the cheapest one they can. There are some people who wouldn't do such a thing, but most buy on price. The plasma companies have been able to cut prices, while still making money. Plasma costs less to manufacture; it's really a simple device.
Plasma Is Stronger than Ever
From Tim Alessi, Director of New Product Development, LG Electronics USA.
Plasma technology has always been appreciated not only for its fast response times and smooth motion, but for its ability to render the deepest black levels and rich, accurate colors. While the most recent advances in LED (light-emitting-diode) backlit LCD sets have closed the gap somewhat, plasma is still the natural choice for discerning home-theater enthusiasts.
LED-based LCD TVs will always have an advantage in power consumption due to the nature of the technology, but plasma has made significant
LG's PZ950 is the company's flagship 50-in plasma TV.
advancements in reducing power consumption. For example, one of our current 60-in. plasma sets would cost about $15 more per year to operate than a 65-in. LED-backlit LCD TV (closest size match). For someone who appreciates the performance of plasma, this would not be a significant factor in the purchase decision.
There are tremendous values in plasma at every screen size. Generally speaking, a consumer could find a plasma TV for between 10 and 20% less than a similarly sized LED-backlit LCD, depending on the features. The great picture performance in plasma, coupled with the price advantage, offers tremendous value across the board. With regard to full HD vs. 720p panels, the market is about 3:1 in favor of 720p, due to the great values in 42- and 50-in. sizes.
Our plasma business has been stronger than ever in the U.S. and we're looking forward to introducing our new lineup at CES in 2012.
Best Image Quality
From Jim Noecker, Sr. Business Development Manager, Flat Panel Displays.
Our high-end customers agree that plasma continues to be the best in terms of image quality.
For example, we sell to the production studios for movies and TV and they won't even let an LCD in the door. The viewing angle alone is where plasma is better. With LCDs, you have motion blurring. And the local dimming technology in LCDs can lead to "halo" effects.
There is still plenty of room for LED-backlit LCDs as well as plasma. In a bright-ambient setting, the LCD is better. That's why we sell a lot of LCDs for signage.
With regard to Energy Star and energy usage, plasma TVs are not energy hogs anymore. Our plasma models meet the Energy Star standards. We still see a lot of legs in plasma.
Q: For years, plasma TVs have come under fire for using too much energy, even as manufacturers have lowered the required wattage. Do power-saving LED-backlit LCDs make it more difficult for plasma to compete?
A: Most plasma and LCD models right now meet the EPA Energy Star standard, which is getting to be pretty challenging. This has been a horse race in which one technology gets a little ahead, then the other catches up, and so on. Right now, I think plasma is slightly ahead of CCFL LCDs. And I believe the LED LCDs are probably a bit lower in power than plasma.
But they are all getting to be pretty low power. The new Energy Star standard, 5.3, which came out last September, was calculated in a new way. In the past, the authors acknowledged that power was going to scale with the area of the display. If you are putting out more lumens, you're going to dissipate more power – that's only logical. But for standard 5.3, they used a linear scale with area up to 108 W. Once you get there it plateaus and stays at 108 W no matter how big the panel is. A 65-in. panel is going to pull more than 108 W, so it's not going to get an Energy Star sticker. That's going to cause trouble for both LCD and plasma. I think in the plasma world, the 42- and 50-in. models will probably make the standard, but not a 65-in. model.
What is really of interest is the 108 W. In the early days, a 50-in. plasma used 550 W. There have been tremendous advances, and 108 W is remarkable.
So, to sum up, the LED backlit is a little better in terms of energy usage, but the differences may not be too important. Let's say the LED panel uses 88 W and the plasma panel uses 108 W – a difference of 20 W. When you go into the stores now you will see these yellow tags on the sets that indicate what the annual cost is going to be in terms of power. If you watch 4 or 5 hours of TV a day, 20 W may cost a couple more dollars a month. If you compare that cost per month with the overall panel cost, I still think you'll find the plasma will provide a lower total cost of ownership than the LCD.
Q: What about some of plasma TV's perceived disadvantages,such as maximum luminance, lifetime, burn-in, and weight?
A: For maximum luminance, you're going to do better on the LCD than the plasma. An LCD can have a backlight of any luminance you want. The plasma can't do that. It's constrained by what the plasma pixels can do and how fast they can pump out light pulses. Everything is done with the pixel. The LCD does everything with a systems approach; it uses the backlight as one part of the system, the liquid crystal as another part, the brightness-enhancement films as another, and so on. But do you need maximum luminance? The high luminance is useful if you have high ambient illumination, but you really don't need it otherwise. So that's a disadvantage to plasma but I don't think it's a large one.
Lifetime is not a disadvantage; it's a big advantage for plasma. Plasma's guaranteed lifetime to half-luminance is 100,000 hours. You won't find a number near that for an LCD; the highest you'll see is 50,000 or 60,000 hours. The backlights are made up of two possible technologies: CCFL (cold-cathode fluorescent lamp) and LED. CCFLs burn out at a certain age. LEDs also are not infinite life devices. They will fail and lose luminance and LEDs will shift color. They are very sensitive to temperature in terms of color.
With regard to burn-in, plasma was the first display out there with large screens, so a lot of them were put in airports and public places where they have the display on 24 hours a day and there might have been some number on in the corner all the time, which left a fixed-pattern image. Since then, the phosphors in plasma have gotten much, much better. That's why they have such a long half-lifetime now. I have a 50-in plasma TV [in my house] that's on much of the time, sometimes even in freeze mode when my wife pauses it and comes back 3 or 4 hours later. It's about 9 years old – I wrote an article on it in 2003 for ID magazine. That panel is still going and there's no sign of burn-in. The other panel I bought at the time for that very article was a 32-in. LCD. It has failed miserably. It has a big blob in it that's due to the liquid crystal. But there really isn't a plasma burn-in issue for TV images. If you put a fixed pattern image on any emissive display – CRT, OLED, plasma – yes, burn-in can happen. But TV images aren't that way. They move around.
The plasma is a little heavier than the LCD because the glass is thicker. The LED backlights can be pretty light and the glass for the LCD is usually lighter. But are you carrying these around?
Q: What about pixel resolution?
A: It's all the same now – HD [up to 1080p]. I should say that even though HD plasma is sold and you can buy it in full high resolution, a lot of people buy the 720p panels and they do that because they're $100 to $200 cheaper. The resolution is there; it's available, but many people want a bargain. The major choice you have today is size, which keeps getting bigger and bigger.
Q: Are companies closing their plasma lines or holding strong? How many plasma manufacturers are left?
A: Last year, the number of panel manufacturers was three. The players were Panasonic, Samsung, and LG. The year before, there were four, but Pioneer sold its operation to Panasonic. The year before that, Hitachi was in operation, but it sold its line to a Chinese company, so that this year we have a new plasma manufacturer, which is Changhong. They are a giant, well-established TV company in China. In addition to the old Hitachi plant, they just finished a new $1B plant in Szechwan. I went through it about a year ago when it was just in pilot production.
The Future of Plasma
Last year, 19 million plasma TVs were sold. This was a record, even though there have been a lot of market people predicting the demise of plasma for the last 10 years. The LCDs were going to take over! LCDs certainly did a great job of capturing market share, but it didn't put plasma out of business. Plasma continued to grow, although it didn't grow as much as it would have if the LCD wasn't there. So, LCD took the icing off the cake but didn't eat the whole cake. Last year, plasma even recovered some of the market share from LCDs.
The next competition will be OLED TVs (organic light-emitting diodes). But they are going have a hard time with price. They can't be as cheap to make as the LCD variety. And they still have to demonstrate their 100,000 hours of life, which is going to be difficult. But they sure look good! •