2007 seems to be the year of the LCD. In TV land, liquid crystal displays have always played little sibling to plasma technology. The most obvious form of tutelage: They have literally been small in comparison. At last year's CES, for example, Panasonic unveiled a plasma TV measuring 108 inches diagonally. Meanwhile Sharp introduced the largest LCD panel—at "only" 65 inches. This year, Panasonic was still pimping its 103-inch TV, while Sharp stunned everyone by debuting a 108-inch panel. For the first time ever, the biggest TV in the world is an LCD. Size isn't all that matters, though. Companies also introduced technologies to zap LCD's other weaknesses vis-a-vis plasma:
Motion video is a classic problem. Liquid crystals move sluggishly compared to fast-firing plasma pixels. So in action scenes, images on LCD sets tend to have a smeared look because the screen can't refresh fast enough. Until recently, 8 milliseconds was considered fast for an LCD pixel to turn on and off. This year LG Electronics showed off TVs with a 5ms response, and Sharp set the record with 4ms. The faster pixels allowed Sharp to double the screen speed from 60fps to 120fps. Philips and Samsung also showed off 120fps sets. Demos of panning video with the old and new technologies made the improvement clear.
Contrast ratio is another weakness. LCD screens usually can’t produce dark tones as well as plasma, because some glow from the fluorescent backlight always leaks through the screen. With grayish blacks, the ratio of light to dark is reduced, and LCD images lack the depth found on plasma. But Sharp claims its new TVs hit a contrast ratio of 15,000 to one by dimming the backlight as needed. Plus, the faster pixels can shut down all the way before switching to the next frame of video. Samsung bested this performance by using a grid of light-emitting diodes as a backlight. It can selectively brighten or dim the lights behind different parts of the screen to deepen shadows and brighten highlights. With it Samsung claims a 100,000 to one contrast ratio, and its side-by side comparison of old and new technologise was dramatic. But Sharp doesn't take that lying down. Using undisclosed technology, it demonstrated a prototype TV that hits a million to one ratio.
LEDs are also expanding color. Until recently, no TV could produce all the hues called for in the US television standard, but plasma came closest to 100 percent. With LEDs instead of fluorescent bulbs behind their screens, LCDs are now beating plasma and going beyond the old TV standard. In fact, Sony is backing a new system called x.v.Color that takes advantage of the newly expanded color gamut. LG and Samsung are also bringing out LED-illuminated LCD sets. —Sean Captain