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Posted on 01/13/2005 7:56:58 AM PST by 68skylark
HREE years ago, liquid-crystal-display computer monitors were mostly sleek, expensive novelty items. Now, of course, every cash register and home computer package comes with one.
But the changes in the world of flat-panel displays go beyond affordability. The panels' physical advantages (smaller footprints, lighter weight and lower power consumption) have been matched by technical advances that make them a better choice than traditional monitors for many of the most demanding computer users.
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Roy S. Berns, a scientist who studies color reproduction and theory at the Munsell Color Science Laboratory at the Rochester Institute of Technology, said he would not have considered using a flat panel in his work a few years ago. For one thing, the colors displayed by early models changed dramatically when viewed just slightly off angle.
Today, however, L.C.D.'s, mostly off-the-shelf models from Apple, have dislodged conventional cathode-ray-tube monitors for use in visual experiments at Munsell.
"The flat-panel manufacturers have put a lot of effort into making L.C.D.'s outperform C.R.T.'s," Dr. Berns said. "Their image quality is better, they're brighter, they just appear more colorful."
Of course, not all L.C.D.'s are bigger, brighter, better and cheaper. Dr. Berns noted, for example, that displays on laptops, where battery life and robustness are critical design elements, can be problematic in terms of image quality. And much computer software - especially the Windows operating system - has failed to keep pace with advances in display technology.
Recent evaluations of several current L.C.D. monitors, however, showed that while they were not all created equal, all but the least expensive models were significantly better than earlier generations. And for buyers willing to do a little homework, there are some specifications that can help sort out the confusing array of models.
For people with more desk space than money, conventional C.R.T. monitors may still be worth a look. Very good models are inexpensive, and unlike many technologies approaching obsolescence, current C.R.T.'s are probably as good as they can be.
But fundamental differences between the two kinds of displays clearly give the edge to flat panels. C.R.T.'s create images by zapping a phosphor coating with electrons to make it glow. Different phosphors create red, green or blue light. Various practical considerations limit their brightness, while even relatively weak magnetic fields, like those generated by loudspeakers, can divert the electrons, causing on-screen distortion.
The illumination from L.C.D.'s, by comparison, comes from several small florescent backlights. On top of those lamps is an array of tiny red, green and blue filters. The task of the liquid crystals is either to block the light passing through the filter array - creating the appearance of black - or to open up and let the light through to the user's eyes. The fixed color array minimizes distortion. And making an L.C.D. monitor brighter is mostly a matter of strengthening the backlight - at least in theory.
But one problem with early L.C.D. displays persists with some of today's least expensive models: their liquid crystals allow some light to leak through when they are closed. That reduces the contrast of images and can make text harder to read and photographs seem less vibrant.
Monitor contrast is measured by using a ratio that compares the brightest and darkest parts of the screen. All but the least expensive 17-inch flat panels now available have ratios of 400:1 to 600:1. (Many manufacturers have increased the ratio by installing brighter backlights. But most L.C.D.'s I tested could be used only at brightness settings well below maximum levels in rooms that are not flooded with light.)
The 17-inch Samsung SyncMaster 711T ($600; www.samsung.com), however, claims a contrast ratio of 1,000:1, thanks in part to the use of liquid crystals that release relatively little light when closed. The result is a crisper display.
Like many performance metrics, however, contrast ratios do not always accurately reflect reality. The Sony HS74P ($450; www.sonystyle.com), another 17-inch display, has a 500:1 ratio, half that of the Samsung, but it appears to have about the same contrast. The trick, according to Sony, is a new method for coating the outside of the screen. On most L.C.D. displays, a fine spray of silicon oxide is applied to help diffuse surface reflections. The Sony panel - and its 19-inch sibling, the $850 HS94P - instead have anti-reflective layers underneath a shiny glass cover. The resulting difference is similar to that between a glossy photographic print and a matte one. Like glossy snapshots, however, the Sony monitors will reflect bright lights that are aimed directly at their surface.
Most manufacturers have also reduced or eliminated a problem that reduced the appeal of flat panels for serious gamers and people who watch videos on their computer screens. Opening and closing the three liquid crystals blocking each pixel's trio of color filters is not an instantaneous process. As a result, early flat panels literally could not keep up with fast action in videos and some games.
But recent L.C.D.'s have speeded response by adding processing power and by refining the crystals' basic structure.
Phil Engstrom, the manager of technology development at the video game maker Electronic Arts said that any monitor with a response time of less than 25 milliseconds should be satisfactory with any game or video. Some of the monitors I looked at do considerably better. The Sony, for example, clocks in at 16 milliseconds.
A way that users can improve the speed performance of a monitor is to buy a computer that can send a digital signal directly to the monitor. Many Windows computers still generate an analog monitor signal to accommodate C.R.T.'s. (Apple switched to digital output about four years ago.) Because of that, special processors in L.C.D. monitors must convert the analog signal into a digital one before telling the pixels what to do. Some very low-cost L.C.D.'s, though, do not have digital feeds.
Improvements to liquid crystals have also solved an issue of broader concern. Dr. Berns, the color scientist, said the biggest change in flat-panel monitors was their improved off-angle visibility. With many early L.C.D.'s, the color and brightness of an image could appear differently to two people sitting side by side. While the problem persists to some extent, it is much diminished. Apple, for example, says that images on most of its L.C.D.'s can be viewed without shift from within a 170-degree arc.
Perhaps as a way to distinguish their products from low-cost models, several flat-panel makers have added gimmicks to their displays. The Samsung 717T, for example, rotates 90 degrees to provide a vertical field for viewing word-processing documents. Others, like the 23-inch NEC MultiSync LCD2335WXM ($1,200, www.necmitsubishi.com), have speakers and television tuners, allowing them to do double duty. Of course, most people do not keep their computers in the same place they watch television. And even Andres Maldonado, a top marketing executive at NEC Mitsubishi, acknowledges that the two-in-one concept has limitations.
"People have been talking about this convergence between TV and PC for a while," Mr. Maldonado said. "We sort of were hesitant to jump on that bandwagon."
While flat-panel monitors are brighter, bigger (Apple offers a 30-inch model for $3,000), their images are not necessarily sharper. The problem, Mr. Maldonado said, is not L.C.D. technology. His company, for example, already makes high-resolution screens for viewing medical images. Instead, the monitor industry is waiting for Windows to catch up.
The physical grid of L.C.D.'s means that they can display images at only a single resolution, unlike conventional monitors. But Windows XP usually defines the dimensions of objects on screen in terms of the number of pixels (say 10 pixels by 15 pixels), rather than in linear terms. That means that if an L.C.D. maker improves resolution by shrinking the pixels, it will have the effect of miniaturizing everything that appears on the screen. While Windows allows users to increase the size of objects, the result is frequently distorted typefaces and disrupted formatting of documents.
Mr. Maldonado said that NEC Mitsubishi and other flat-panel makers were working with Microsoft to correct the problems in the next version of Windows. But for people who do not want to wait, Apple's OS X operating system solved them several years ago.
When Windows does catch up, it is not likely that a resolution war will erupt. At 100 pixels per inch, Apple's current L.C.D.'s are just slightly higher resolution than the 96 pixels per inch offered by most Windows-compatible screens. Scott Brodrick, Apple's product manager for displays, said 100 dots per inch would be the limit for the foreseeable future. Anything higher would require computers to add extra pixels to display digital snapshots at a reasonable screen size, he said, a practice that might introduce distortions to the photos.
But unlike C.R.T.'s, which are subject to distortion as their screens grow larger, Mr. Brodrick sees little to limit the size of liquid-crystal displays. And for people who are not satisfied with a 30-inch screen, Mr. Brodrick said PowerMacs can already run two of the large monitors simultaneously.
"That's five linear feet of display," he said.
Click the link above for a slide show on flat-panel screens and other background from the Times.
I'll be using my 50" InFocus DLP soon.
Have had a Sony 18" LCD monitor for about 3 years now. It is fabulous! Stunning colors, clarity and saves a whole lot of room on the desk compared to the CRT.
The article reads like an advertisement for Apple.
That probably explains why I have seen recent discussions around here of some sort of software patch for Windows that "makes on-screen text look almost as good as printed text".
At the time, I couldn't figure out why this was such a good deal -- since my Mac displays have always looked as good or better than printed text.
Has anyone noticed lately how many writers (like this one) are saying , "of course, the Mac doesn't have that problem."?
I am always amazed at the folks who are suckered by the "we're the best" marketing BS from Microslop -- and then put up with all the deficiencies and patches needed to keep/get their PCs running right. I call them "MS Sheeple".
Can't help but wonder if the new $499 "Mini-Mac" is going to start to change that...
Nope -- just reflecting reality. (See my preceding comment...)
I bought a LCD TV from Dell last fall for the bedroom, pretty cheap, good picture for watching in bed.
Once people can buy a 35 to 40 inch LCD TV for $500 sales of "regular TV's will drop by 80%.
You mean it isn't? There was not a doubt in my mind.
What a bunch of hogwash.
Look at an lcd screen head-on and it looks good.
Step to the side by 2 steps and you can no longer see a discernible pic.
Stand up and you can no longer see a discernible pic.
I'll stick with CRTs until they are no longer available.
I am always amazed at the folks who are suckered by the "we're the best" marketing BS from Microslop...
Ahhh, the subpixel rendering done in XP. You haven't seen it, I take it - give it a look, you might be surprised. Personally, I'm always amazed by people who assume that the box with a picture of fruit on it is automatically superior in every single aspect, even though they admit right off the bat that they don't actually have a clue about the thing they're comparing it to ;)
If you look at Toms Hardware, the Samsung's get extremely favorable ratings for color reproduction and contrast. Have been using a 910T calibrated by ColorVision Spyder for a couple of years and would never go back to a CRT even for photography work.
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