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The Skinny on LCD

Of course, every notebook computer has an LCD. The earliest laptops used 8-inch (diagonal) passive-matrix black-and-white screens. But as LCDs evolved toward active matrix, display sizes grew. Today's LCDs almost exclusively use TFT-based panels, which can provide bright, sharp displays in much larger sizes. But the size of the laptop itself is a constraint. You're not likely to find laptop LCDs larger than 15.1 inches across. Anything larger will most likely be used for a desktop LCD.

Many PC vendors now offer LCDs as options with new desktop PCs. Gateway, Dell, NEC, and Acer, among others, all offer flat panels as part of low-cost desktop system packages or all-in-one PCs for the home office. To keep the price of these packages down to earth, the vendors sometimes use slightly older or less-expensive components elsewhere in the system, and play up the aesthetic appeal of the flat-panel desktop as a Star Trek-like home accessory.

ViewSonic, NEC, and other monitor vendors offer desktop LCDs ranging in size from 14 inches (for a reasonable $600) to 18 inches (with street prices upward of $3500). (Note that vendors measure LCDs' viewable screen area and not the size of the tube, as they do with CRTs, so the viewable area of a 15-inch LCD is the same as that of a 17-inch CRT.) Some stand-alone LCD monitors are designed so that the screens swivel from landscape to portrait orientation, and some come with USB hubs and protective screens. All of these things add to the price.

Still, LCDs make up just 2 percent of overall monitor sales, according to analysts at San Jose, California-based Stanford Resources. That may change as prices fall. Fifteen-inch LCDs, which range in price from $800 to $1200, make up 75 percent of desktop LCD sales. By comparison, 17-inch CRTs cost just $200 to $350. Analysts expect 15-inch LCD prices to drop this year, to an average of $900, as manufacturing costs decrease.

If you're choosing between analog and digital, you'll probably have to trade off quality for economy. Because analog models have to convert a data signal twice, they have problems rendering images. Digital LCDs do a better job but require special graphics adapters with a digital interface. So although digital LCDs cost a bit less than their analog counterparts, on average, keep in mind that you'll also have to buy the adapter.

Mercifully, a standards war over digital interfaces--a battle between the Video Electronics Association (traditionally the arbiter of video standards) with its Digital Flat Panel standard and the Digital Display Working Group (composed of vendors such as Intel, Compaq, and NEC) and their Digital Visual Interface standard--has ended, with DVI the clear winner. Widespread vendor support for DVI means nearly all new digital LCDs use the DVI standard, as do graphics boards with digital connectors.

Additional resources:

• Sharp's World of LCDs
  
  
• Digital Display Working Group
  
  
• Video Electronics Standards Association
  
  
• Stanford Resources
  
  

Michael Gowan is a staff editor for PC World.