LCD: Liquid Crystal Display HDTVs can make for excellent HDTV viewing. Here are a few reasons why:
- Excellent color: LCDs can display millions of colors and do so accurately (meaning the color coming off the screen is faithful to the color in your broadcast or recording).
- PC-monitor-capable: You can use many LCD HDTVs as big (huge!) PC monitors.
- No burn-in: HDTVs that rely on phosphors, such as CRTs and plasmas, can, under certain circumstances, experience burn-in, where ghost images are permanently burned into the screen. LCDs are immune from this phenomenon – so feel free to play video games, watch the CNBC stock ticker all day, and so on with no fear.
- Inherently progressive: LCDs use millions of tiny transistors that can be individually controlled by the “brains” inside the display. So LCDs can easily handle progressive-scan sources.
You may want to consider a few other issues before you choose an LCD HDTV:
- Expensive for their size: LCD HDTVs are great, but they’re not cheap. Of course, all flat-panel TVs are relatively pricey, but LCD HDTVs typically cost more, per inch, than do plasmas.
- Poor reproduction of blacks: Black images are among the hardest for most TVs to reproduce. LCD TVs tend to produce grays, not blacks.
- Limited viewing angle: LCDs typically have a poor viewing angle – the angle you can sit away from perpendicular and still see a clear image on-screen. Manufacturers have been working diligently to improve this characteristic (with some success). Check the specs before you buy – most LCD HDTVs have viewing angles listed in their specifications.
- Slow pixel response time: The individual pixels within an LCD HDTV take a slight amount of time to change color and intensity. For really fast-moving video content, an LCD TV can end up with some artifacts (visible flaws) where the picture from a previous frame is still slightly visible on-screen as the new one is being drawn. Typically, this isn’t a huge and noticeable deal, but it’s not beyond the realm of possibility that you may notice it.
- Limited brightness: The LCD is a transmissive system – light is shined through the liquid crystals. Some of that light gets absorbed or reflected back away from the viewer. This means that LCD displays are not as bright as CRT, plasma, and even some projection TVs – this could be a factor in a brightly lit room.
PLASMA: Plasma TVs combine a thin, compact chassis with a truly large (even huge) screen size, and then add beautiful high-definition pictures to the mix.
A plasma screen contains literally millions of gas-filled cells (each one acting as a single image pixel) trapped between two pieces of glass. An electrical grid zaps these cells and causes the gases to ionize (and ionized gas is plasma – hence the name). The ionized gases, in turn, cause a layer of phosphor on the viewer’s side layer of glass to light up.
Despite their compact dimensions (in the “depth” direction at least – many plasmas are only about 4 inches deep), you can find plasma HDTVs in 42-, 50-, and even 60-plus-inch sizes. Imagine a 4- or 5-inch-deep HDTV that spans 5 feet diagonally, and you can see the instant appeal of plasma.
Other benefits of plasma displays include:
- Excellent brightness: Plasma HDTVs don’t rely on a light bulb shining through or reflecting off of something (as an LCD or DLP system does). Plasma brightness is even better than CRT’s in some ways because the picture is evenly bright across the entire screen. In a CRT, on the other hand, you always have some slight (or not so slight) difference in brightness as the electron beam reaches different parts of the screen.
- High resolution: The finest plasma TVs have such high resolutions (and such smooth images) that they look like nothing more than beautiful film images.
- Progressive by nature: All the pixels on the screen light up simultaneously. You can have progressive HDTV sources (such as 720p) and non-HDTV sources (such as progressive-scan DVD players) displayed to full advantage on a plasma HDTV.
- A wide viewing angle: Plasma displays have a good picture even when you’re sitting “off axis” (not perpendicular to the screen surface). This is a huge benefit for smaller rooms, where viewers may sit relatively far off to the sides of the screen, at wider angles.
Plasma’s not perfect, of course:
- Susceptible to burn-in: Any system that uses a phosphor screen to display video can fall victim to phosphor burn-in.
- Shorter lifespan: Another phenomenon of any phosphor-based display system is that eventually the phosphors “wear out” or lose their brightness. This is a subtle and slow process, but it inevitably happens.
- Less-than-perfect color reproduction: Although plasma displays can produce a breathtaking array of colors, a lot of sets have the unfortunate tendency to make red colors look more orange than true red. If you’re a huge fan of slasher horror flicks, this may take away some of your fun!
- Poor reproduction of black: Plasma TVs fall short in the realm of reproducing black images. Most plasmas do slightly better job than LCD TVs at black reproduction, but they fall short of CRTs and some projection systems.