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An LCD on Every Desk

By Mark Clarkson

2005 will be the year of the LCD monitor; more than half of allmonitors sold this year will be flat-panel LCDs. By 2007, CRTs areexpected to constitute a mere 10 to 20 percent of new monitor salesworldwide, and most of those in so-called undeveloped nations. It lookslike a liquid crystal future.

View the chart of LCD Providers

So what’s new in LCD monitors? Not a whole a heck of a lot, actually.But that’s a good thing. Really. There comes a time in the developmentof every device where the technology and standards stabilize, where wecan all stop memorizing new acronyms and settle down to a nice periodof increased performance and lower prices. For LCD monitors, that timeis now.

At right:The Acer AL1913 (top) and Sony ‘s P234 (below).

The Big Four
When comparing LCD monitors, there used to be four importantperformance specs to keep in mind: brightness, viewing angle, contrast,and response time. But brightness and viewing angle have crossed athreshold; significant improvement here is neither possible nordesirable.

LCD brightness is measured in units called nits: 1 nit = 1 candela persquare meter (cd/m^2). All LCD monitors from major manufacturers provideadequate brightness, between 250 and 300 nits. Anything over 300 nitsis probably too bright for desktop use; light backgrounds tend tobloom, overwhelming small line detail and text. Unless you’re watchingTV on your LCD monitor, or working outside in the sunlight, brightnessis no longer an issue.

Above: One of many NEC-Mitsubishi MultiSync LCDs

The Sharp 23-inch IT-23M1U


Stereoscopic 3D

Stereoscopic 3D viewing for MCAD has been around for a while, generallyaccomplished using special glasses. But Sharp’s new 3D-enabledLL-151-3D LCD monitor offers a glasses-free alternative, creating 3Dstereoscopic images with the LCD monitor alone. The 3D monitor uses anelectronic barrier, built into the display between the backlight andthe LCD transistors, which blocks backlighting to alternate columns ofpixels; the left eye only sees the odd columns, and the right eye seesonly the even columns.

“If your software can create two perspective views,” says Sharp’s IanMatthew, “as can 3D Studio Max, CATIA, UGS, for example, our displaywill allow you to view them stereoscopically.” The electronic barrier,and therefore 3D mode, can be switched on and off as you wish.
The display is understandably sensitive to viewing angle and distance,but it beats wearing goofy goggles. The LL-151-3D sells on the streetfor about $1,500.
— MC
Hyundai ImageQuest L90D

Likewise, viewing angle is no longer an issue; good monitors now boastviewing angles in the realm of 88 degrees. In fact, you can buy privacyscreens to fit over an LCD monitor to artificially reduce its viewingangle.

An LCD’s contrast is measured as the ratio of its whitest white to itsblackest black. The higher the contrast ratio, the better you’ll findthe image on the screen. A few years ago, LCD monitors offered contrastratios of maybe 150:1. Good numbers today are at 500:1 and above;performance monitors provide contrast ratios of 1000:1. Somewhere inthere, it becomes difficult for the untrained eye to detect anydifference.

Response time is where the real spec wars are happening today. Responsetime is a measure of the time a given pixel takes to go from on (white)to off (black), or vice versa. A monitor’s response time determines howquickly and crisply it updates. A year or so ago, a response time of20-25 ms was about the best you could do, and there are still a lot of25 ms monitors on the market. Twenty-five ms is slow enough to give youvisible smearing and ghosting, leaving rapidly moving images (e.g.,rotating 3D objects) looking a bit blurry.

But somewhere around 12-16 ms, response times become fast enough formost people and applications. And response times have fallendramatically in the last year, to as little as 8 ms. Generally, largerLCD monitors have worse response times than smaller models, 12 to 16 msinstead of 8 to 10 ms, but that’s changing weekly. Samsung’s newSyncMaster 915N 19-inch LCD sports an 8 ms response time—the fastest inthe industry today

Assorted Pros and Cons 

Left: Gateway

Once you admit that LCDs look good enough—in terms of brightness andcontrast and response time—you’ll find they have lots of otheradvantages over CRTs. A 17-inch LCD consumes roughly half the power ofa 17-inch CRT. If you’ve got an office with 100 computers, that’ssignificant (about 5,000W).

LCD monitors, unlike CRTs, are digital devices; PCs are also digitaldevices. Add a digital video card in between and you get a puredigital-digital-digital hookup, and a very crisp image.

LCDs are much smaller, lighter, and easier to move around. In fact,because LCDs have smaller footprints, a lot of people are getting two,running a pair of 17-inch or 19-inch monitors side-by-side, as a singledesktop.

There are, admittedly, drawbacks to LCD monitors, the most obviousbeing the price tag. For now, and for the immediate future, CRTmonitors will sell for less. But the price differential is changing,and LCD prices are falling faster than CRT prices, dropping about 50percent in the last year.

Unlike CRTs, LCDs don’t adapt readily to different resolutions. Becauseeach pixel corresponds directly to a chunk of hardware in the display,LCDs are locked into a native resolution (1280 x 1024 for 17-inch and19-inch monitors; 1600 3 1200 for 20-inch monitors). If you run your19-inch LCD monitor at 1024 x 768, it has to scale the image to fit itsnative 1280 x 1024 space and the results look fuzzy, at best. Some LCDswon’t run outside of their native resolution at all.

If your environment requires you to run a variety of resolutionsfor some reason (proprietary applications sometimes require fixedresolutions), stick with CRT monitors for now. The fact is, though,that most of us don’t change resolution any more; it’s a feature of CRTmonitors few will remember to miss. 

It’s Inevitable

So you can wait, if you want. Contrast ratios and response times willcontinue to improve. Screen sizes will go up, and prices will fall.LCDs will just get more and more attractive until, eventually, you justcan’t resist them anymore. There’s no getting around it: There’s an LCDmonitor in your future.

Mark Clarkson is a writer, an artist, and the long-lost Dauphin. Hespends long hours in his secret basement workshop, crafting articlesand books about all manner of technology. His latest book is PhotoshopElements by Example. Visit him on the Web at markclarkson.com.You canalso send e-mail about this article addressed tode-feedback@helmers.com.

About Mark Clarkson

Contributing Editor Mark Clarkson is Digital Engineering's expert in visualization, computer animation, and graphics. His newest book is Photoshop Elements by Example. Visit him on the web at MarkClarkson.com or send e-mail about this article to DE-Editors@digitaleng.news.