Pros and Cons of Plasma Displays - dummies

By Danny Briere, Pat Hurley

A plasma TV (often called a PDP, or plasma display panel) is a flat-panel display that contains millions of gas-filled cells, or pixels, wedged between two pieces of glass. An electrical grid zaps these pixels and causes the gases to ionize (the ionized gas is plasma — hence the name). The ionized gases, in turn, cause a layer of phosphor on the outside layer of glass to light up.

Plasma displays have captured the attention of the home theater industry and home theater consumers because of the sheer size and quality of the picture they can produce. Plasma displays are available in 42-, 50-, 56-, and even 65-inch sizes — and they can get even bigger. Even at the larger sizes, the display itself is usually no more than 5 or 6 inches deep — and suitable for wall hanging. All the plasma displays in these sizes have a 16:9 aspect ratio.

Benefits of plasma displays

Other benefits of plasma displays include the following:

  • Excellent brightness: Because plasma displays use the direct lighting of phosphors (instead of a backlighting system in LCDs), they can have an extremely bright and crisp picture. Because each pixel is controlled directly by the electrical grid behind the plasma cells, the brightness tends to be extremely even across the screen.

  • High resolution: Most plasmas these days are at least 720p capable and many are 1080p capable. Just about all plasma displays on the market are 16:9 aspect ratio sets, which is also essential for HDTV viewing.

  • PC monitor-capable: Most plasma displays can be plugged directly into any PC (not just home theater PCs with special TV video cards) to act as a gigantic PC monitor.

  • Progressive by nature: Plasma systems don’t use a scanning electron beam to create a picture. Instead, all the pixels on the screen are lit up simultaneously. So progressive video sources display progressively on any plasma system.

  • A wide viewing angle: Plasma displays have a good picture even when you are sitting “off axis” (not perpendicular to the screen surface). In a smaller room, where some of the seating might be at an acute angle from the screen, the wide viewing angle can be a big plus.

Drawbacks of plasma displays

Of course, the plasma equation has a few downsides in addition to a high price tag:

  • Susceptible to burn-in: Any system that uses a phosphor screen to display video can fall victim to phosphor burn-in. If you do a lot of video gaming or stock or news ticker viewing, you need to be aware of this fact. Manufacturers of plasma TVs have made great strides in reducing the possibility of burn-in, and many plasma TVs have burn-in fix-it programs that generate a series of images onscreen designed to remove any minor burn-in from your screen.

    You can minimize burn-in on any plasma display by calibrating the set properly and by reducing the brightness from its factory setting, which is usually too high.

  • Shorter life span: Another phenomenon of any phosphor-based display system is that eventually the phosphors “wear out” or lose their brightness. Given the considerably higher cost of a plasma, your cost per hour of viewing is much higher. Before you buy, check the manufacturer’s specifications on hours to half brightness, which is the point at which the display is only half as bright as it was when new.

  • Not as high resolution as LCD: Even though 1080p plasmas are becoming more common, the majority of mainstream plasma TVs offer “only” 720p resolution. We suspect that within a year or two, just about all plasmas, at least those 50 inches and larger, will be 1080p, but today that’s just not the case.

  • Poor reproduction of black: Like LCDs, plasma displays have a hard time reproducing black, so black scenes end up being reproduced as shades of gray.