New Larger TVs Favor LCD Over Plasma

Information Week is carrying a Reuters story examining the shift towards LCD technology in recent large-screen television models. Though some analysts acknowledge that plasma displays have faster response times over large surfaces, the industry seems to be betting that consumers will prefer higher resolution images over time. From the article: "CPT's Wu agrees that plasma panels, especially 50-inch and larger ones, do excel LCDs in some aspects of picture quality, but he says the sheer size of the LCD camp will help LCD panels overcome whatever drawbacks they have in a timely manner ...With the 40-inch-class market gradually taken over by LCD TVs, plasma models need to migrate to the market for 50-inch TVs and above, but demand is not as well developed there, analysts say. 'The United States accounts for more than 70 percent of demand for 50-inch plasma TVs and larger. In other words, there is virtually no 50-inch-class plasma TV market outside the United States,' DisplaySearch director Hisakazu Torii said."

Comments

Energy efficiency

[pe1chl]

It may not be a factor in the US market, but here in Europe plasma's have a bad reputation because of their energy consumption.
Household equipment is rated in the shops on an energy efficiency scale, and LCD screens score much better than plasma.

Furthermore, plasma has a tendency to burn in. Of course every manufacturer and salesman will tell you that "this is no longer true", but once the problem has happened they are not so firm in their statements anymore.
This causes trouble when watching 4:3 transmissions in true 4:3 format (rather than stretched to 16:9).
It also sometimes causes station logos or newstickers to burn in.

Re:Energy efficiency

[Osty]

LCDs also burn in.

No they don't. Plasmas suffer burn-in because they emit colors in the same way as a CRT -- using red, green, and blue phosphors. "Burn-in" happens when the phosphors age non-uniformly, such as when a static image is held in place too long. You can combat this by properly setting your contrast (TVs are set to torch mode in the stores because it looks better under the flourescents; at home you should have your contrast set to a much lower level) and by pixel-shifting, but you can't eliminate it so long as the technology uses a consumable resource for emitting colored light (phosphors).

LCDs and DLPs don't burn in because they use filters over white light to emit colors. DLP does this with a color wheel rotating anywhere from 10,000 to 30,000 times per second, with the DMD adjusting for each window of the wheel to emit the correct amount of the base color of light (basic wheels contain red, green, and blue filters. Better wheels double up on the colors and often add several different shades of blue and green since our eyes are more attuned to those colors than red. Non-consumer high-end models have individual DMDs and filters for each color). LCDs have discrete filters for red, green, and blue, and the liquid crystal is set to a state to allow just the right amount of each through (thus you can do sub-pixel rendering, such as Cleartype font-smoothing). But it's still all about emitting filtered light, not emitting colored light from a phosphor. Your backlight may go out, but that's replaceable. Good luck replacing individual phosphors when they burn out.

Re:Energy efficiency

[CaxDot]

The reason LCDs are outselling plasma displays is mainly that they are sold in brightly lit stores, where you won't easily see the enormous difference in contrast ratio. On the contrary, LCDs are fabricated to look black in direct lighting, while plasmas sometimes tend to look greyish.

Good stores should have dampened lighting in the TV dept. Plasmas are like projectors, you don't really see what they are capable of in bright light. Turn the lights down on an LCD, and you will see the disastrously poor contrast of LCD technology manifesting itself as glaring, grey areas that are supposed to represent black.

The other reason is that LCD are preadjusted to do a lot of clipping in white and black areas (which people don't always easily react to) to make the picture look less washed-out. If you correctly calibrate an LCD you will see this limitation quickly.

To further fool the customers, LCD vendors have a fantast-number called "dynamic contrast", which represents total contrast after frame-by-frame contrast distribution. It would be OK giving ut this specification, had they not omitted the real number. After all, "dynamic contrast 8000:1!" doesn't sound less cool than "contrast 5000:1". It's dynamic, like Batman & Robin. Too bad the real contrast is 1200:1.

So sure, LCDs may be better for use with a computer, but that is not the reason why they are winning the battles in the elecronics stores.

Re:Energy efficiency

[@madeus]

LCDs and DLPs don't burn in because they use filters over white light to emit colors.

Certainly DLP's don't suffer from burn in (though they have a lot of other issues of course, the infamous rainbow effect being the biggest problem - though things seem to be improving on that front) but the same can't be said for LCD TV's. Although Plasma screens seem to burn in more easily, LCD displays do suffer too, however mostly it seems to only be an issue with larger displays (e.g. 30" or larger - the sort of size used in LCD TV's). I am not sure why that is though.

Your backlight may go out, but that's replaceable. Good luck replacing individual phosphors when they burn out.

That's a bit of a red herring to be fair. As with the back lights on an LCD display, Plasma screen will indeed burn out eventually (mine is rated for something like 8 years continuous usage - i.e. so even if I watch 12 hours a day (which obviously I'm not going to) it should be good for 14 years, which I'm comfortable with. Good luck getting either replaced though!

The depressing reality is, unless you have a good 3rd party repair shop in your area that are comfortable with this sort of thing, or you are willing to take your TV apart yourself you are SOL. Vendors like Sony, Phillips (etc.) just don't want to know and that ones that will talk to you invariably give you a price that is equal to or more than the cost of a brand new unit (especially on smaller screens), and of course new sets of better quality will almost certainly be available for 1/4 of the price by then.

Example: I bought a brand new model 32" Sony CRT 8 years ago for 1,500 UKP (the most expensive set in the store as it happened). I'm going to give it to someone in the office who can use a better TV as there is almost no point in trying to sell it - you can get a better set for about 250 UKP now. It has a long-standing problem with powering up from being completely off (it's okay if you leave it on standby, but otherwise you might need to flick it on and off a couple of times), but it would cost about the same as a new set just to get that issue resolved.

Re:Energy efficiency

[jacksonj04]

Leeds spent many thousands on replacing old CRTs with LCDs, which worked roughly alright (Except for the fact that they were ran by Win2K and sometimes got interesting errors) except for, like you said, burn in after a year or two.

They have now been replaced with huge banks of LED displays, similar to those in airports (I believe London KX has done this as well), which are amazingly bright, incredibly readable, and 100x more reliable.

Re:Energy efficiency

[GTMoogle]

If it happens to 5 of 30, it's a manufacturing defect, although one possibly deemed acceptable (or went unnoticed). So a poorly made LCD can have issues with pixel response - it can probably even be fixed by massaging the screen while having it flicker through the color spectrum. YMMV. It works for dead pixels, at any rate. "L" stands for liquid, so gooshing it around may very well have restorative properties. I've never seen a burned in LCD, so I can't say from experience.

The point was phosphors have a lifespan directly related to their average intensity, and for plasmas it's measurable in a matter of years if not months (for the difference between neighboring pixels).

Re:SED anyone?

[Silver Sloth]

From the Wikipedia article you referenced

In October 2006, Toshiba's president announced the company plans to begin full production of 55" SED TVs in July 2007.

So the answer to your question is July 2007.

Memory

[MichaelSmith]

LCD monitors do get imprinted but the image is lost when power is cycled. Perhaps you should switch the monitor off when booting into ubuntu.

Re:Memory

[glittalogik]

LCD burn is fixable. Make a screen-sized white image and a screen-sized black image and run a slideshow of them alternating for a few hours. This basically 'flexes' the light-blocking bits in each subpixel and gets them unstuck. I used to work at Philips and that's how we fixed it on any of the monitors in the office.

Re:Why would anyone buy either?

[kisielk]

I find your comment puzzling. I live in Japan and many of my friends have projectors because their apartments are too small to be able to fit even a modest sized television. With a projector they can have a large screen while taking up very little space. Newer LCD projectors are no bigger than a regular sized laptop and fit easily on a shelf or projector mount. Add to this a screen that you can hang from the ceiling on some hooks, and you can get a 50" TV in a tiny space.

Re:Why would anyone buy either?

[Technician]

There are a number of reasons why people don't want or can't use front projection.

I'm suprised nobody has mentioned lamp life yet. It's a pricy part and has a short life.

2. Video projectors have a very limited bulb life. In other words, if you are watching TV on your video projector about 3-4 hours every night, you would have to replace the light source bulb about once a year at 200-400 dollars a pop.

snipped from

http://hometheater.about.com/od/hometheaterbasicsf aq/f/htbasicfaq5.htm

You mean these...

[thrill12]

made by data display, a UK based company. I used to work on these displays. They also specifically mention the short lifespan of the plasma displays.

Article in IEEE Spectrum

[necro81]

This discussion mirrors an article that appears in the current issue of the IEEE Spectrum magazine. They review the pros and cons of LCD and Plasma technologies, with a brief look at DLP, SED, LCOS.

Their take on it? It won't be settled for another couple of years, and there will be two distinct categories: screens below 50" (or 42"), and screens larger. LCD will dominate the smaller screen size market, though SED may replace that when the cost comes down (after 2010?). For larger screens, don't discount projection technology, particularly in terms of cost.

Incidentally, the cover article for this issue is on Blake Ross, whom they call the Firefox Kid.

Because DLP has inherent limitations LCD doesn't

[StandardCell]

DLP has the following limitations:

1. It is inherently a projector technology, which means:

a. For a front projection situation, DLP image quality is directly dependent upon the illumination within the room and the screen.

b. For a rear projection situation (i.e. the one that looks like a stand-alone TV), DLP requires a screen that has inherently poor viewing angles, particularly when viewed above or below the vertical screen limits. Even older LCDs without the "180 degree" viewing angle are far better than any DLP RPTV screen.

2. It is a technology dependent upon light sources that (currently) have inherently poor lifetimes. Lamps are expensive replacements. When LEDs and lasers come more into the fold, this should alleviate this problem.

(Note: this could also be construed as an advantage since you'd have all new luminance and you can't replace the CCFL backlight in an LCD which has a tendency to degrade unevenly over time).

3. It is a technology that, unless you use three separate DLP chips for the primary colors, will be prone to rainbow effects. Even in the 3DLP setups, convergence can also become an issue.

DLP is good for certain applications but will never be the primary volume driver of the market. Two years ago, it was the only way to get a decent screen size for HD, but not any more. The whole industry has dogpiled onto LCD direct-view, and it'll only get cheaper from here.