Introduction to Plasma Display Technology

This first step is a brief guide to plasma display technology, starting with its history and leading into the main benefits and advantages of plasma displays.

Plasma Technology History

Plasma screens first entered the US market towards the end of 1999, but the concept has been around since its inception in July of 1964 at the University of Illinois. The first displays were nothing more than points of light created in laboratory experiments. The technology was developed and improved, and by the late 60's, it had become advanced enough to allow the scientists to construct geometric shapes. Today the progression in high speed digital processing, materials, and advanced manufacturing technology has made full color, bright plasma displays possible.

Digital television is now a realitybut you're not going to see it the way it was meant to be seen using yesterday's TV sets. Today, we're in the midst of a digital video revolution, thanks to HDTV, DTV, DVD-Video, digital satellite broadcasts and computer video. Plasma display technology is one way to fully enjoy the dramatically improved image quality of all these digital video sources.

Advantages of Plasma Displays

Some of the advantages of plasma technology include:

Higher Resolution
Plasma display devices have higher resolution than most conventional TV sets, and are capable of displaying full HDTV and DTV signals as well as XGA, SVGA and VGA signals from a computer. For example, a plasma display with a 1366 x 768 native resolution can display images from 1080i and 720p HDTV resolution, as well as 480i and 480p DVD video signals.

No Scan Lines
Conventional CRTs use an electron beam to scan the picture tube from top to bottom at regular intervals, lighting the phosphors to create the image. With standard (NTSC) TV, visible scan lines can be seen. Plasma screens have no scan lines due to the fact that each and every pixel cell has its own transistor electrode. This creates a smooth, evenly lit image across the entire surface of the display. Most current plasma displays also include built-in line doubling to improve image quality from low resolution analog video signals.

Exceptional Color Accuracy
Due to advances in both plasma panel technology and digital video processing, today's top-of-the-line plasma televisions can display billions of colors, resulting in smooth gradations between even very subtle shades, and an overall picture quality that is extremely lifelike and realistic. Plasma TVs in general boast the best color reproduction of any flat panel TV technology, and advances are made with each new model year in plasma production. For color accuracy, Plasma televisions are simply without compare.

Wide Screen Aspect Ratio
Plasma televisions have a widescreen 16:9 aspect ratio, which was originally designed to match the natural field of view of the human eye. Of course you're familiar with the wide screen aspect from watching movies in the theater - and a widescreen plasma TV allows you to watch movies in the format the director intended. The 16:9 aspect ratio is also the chosen format for HDTV content, whether it's broadcast over the air or through digital cable or satellite TV.

But what happens when you watch a standard (4:3) TV program or a computer image? Choosing a plasma TV that scales images appropriately will give you the most enjoyment from your plasma, as well as extending its life. There are several algorithms used to scale incoming video signals to match the plasma's native 16:9 aspect ratio. All plasma screens can show the image in its original 4:3 format with bars (either black or gray) on the sides of the image, but there can be some variation among plasma screens in how well they convert a 4:3 image to the widescreen monitor. Manufacturing engineers accomplish a "best of both worlds" approach by limiting the stretching in the center of the screen, or by enlarging the entire image to larger than the screen size, and "cropping" the edges. This scaling technique allows the most stretching to be located on the edges of the image, thus reducing visible distortion.

So basically there are a number of ways to display an incoming "standard" 4:3 picture from satellite, VCR, or cable TV, and some plasmas do it better than others. It can be displayed as is, with the bars on the sides. In "Zoom" mode, the image will have very little distortion or stretching and will fill the entire screen area. However, this mode often cuts off too much of the picture around the edges, and can cause motion artifacts and pixelation - resulting in a "grainy" or jagged appearance.

Typically the best option for converting a 4:3 NTSC TV signal is the "Just" or "Full" mode - you'll see the same idea called different names by different plasma manufacturers. This aspect ratio option converts the 4:3 image with specially designed algorithms, which reduce the visible "stretching" as much as possible by using a combination of techniques, cropping very little of the image and situating any stretching or distortion to the outer edges where it will be less noticiable. If it's done well, you'll hardly notice any difference at all.

Perfectly Flat Screen
Plasma display monitors have screens that are perfectly flat, with no curvature whatsoever. This eliminates the edge distortion that can occur in CRT displays and also assists in allowing the wide viewing angles that are a trademark of plasma displays. The glass-encased plasma display element is most often protected by a Plexiglas layer; some of the better plasma TVs incorporate anti-glare coatings and special color filters to further enhance the picture quality and viewability of the flat screen.

Uniform Screen Brightness
Unlike some rear and front projection televisions that suffer from uneven screen brightness - seen as "hot spots" in the middle of the screen or a darkening near the corners of the image - plasma displays illuminate all pixels evenly across the screen. This gives plasma displays their "smooth" appearance, and ultimately a more accurate picture.

Slim, Space-saving Design
Plasma display monitors are only a few inches in depth, providing installation options never before possible. Depth is usually measured at around 3.5 inches on 42" displays and 4" for 50" screens. In addition to table stand mounting, they can be hung on a wall or from a ceiling, allowing you to enjoy big-screen impact from a component that doesn't dominate floor space. Conventional CRT's, DLP TVs, and rear projection TVs take up far more space and are much more limited in placement flexibility.

Plasma monitors are constructed with a bezel that's not much wider than the actual display screen, giving the monitors an elegant, understated "picture frame" appearance that blends inconspicuously with any d├ęcor.

Because they eliminate the need for a front projection unit and a projection screen, plasma display monitors are also ideal for use in a wide variety of business and commercial applications where the use of a front projector would not be feasible.

Wide Viewing Angle
Today's plasma screen TVs offer viewing angles approaching - sometimes even exceeding - 170°, much better than rear-projection TVs and LCD displays. Coupled with the perfectly flat plasma screen, a good plasma TV even rivals a CRT TV in viewing angles. This allows a bright, clear picture for anyone in the room - no matter where they're sitting.

Universal Input Capability
Nearly all plasma monitors will accept standard video signals via composite video and s-video inputs, as well as higher-quality component video terminals. An important consideration in choosing the right screen for you, however, lies in what other inputs you may need. Many of the newer plasma TVs on the market include digital inputs such as HDMI or DVI, which can accept HDTV signals from your cable box or satellite - even some DVD players - in an all-digital format. Some plasmas also include a VGA or DVI PC input, allowing your plasma television to pull double-duty as a PC monitor.

And don't overlook some of the excellent plasma displays aimed at commercial broadcast installations, such as the Panasonics and Pioneers. Many of these models are equipped with interchangeable input boards, allowing you to configure your plasma display to meet your needs exactly.

Immunity From Magnetic Fields
Components such as loudspeakers that contain strong magnets can distort the picture if placed too close a standard TV. However, because plasma displays do not use electron beams, as conventional CRT displays do, they are immune to the effects of magnetic fields. Plasma displays can be placed in close proximity to any type of loudspeaker and not experience image distortion. This is also the case when crossing into the Southern Hemisphere. Boats may use plasma displays as they are not sensitive to the earth's magnetic fields.