Gas Plasma Displays

An overview of plasma displays

Gas plasma technology is a new way to build video and computer monitors. Essentially plasma units have the brightness and look of a CRT monitor, but they offer a much larger image and are thin enough and light enough to hang on any wall. This combination makes them ideal where lighting conditions would favor a monitor, but audience size indicates a projector. Like LCD displays, plasma monitors do not exhibit the distortion and loss of clarity in the corners inherent to CRTs.

How do plasma monitors work?

Plasma monitors work much like CRT monitors, but instead of using a single CRT surface coated with phosphors, they use a flat, lightweight surface covered with a matrix of millions of tiny glass bubbles, each having a phosphor coating. These phospors are caused to glow in the correct pattern to create an image. (click for details)

What are the advantages of plasma?

Plasma monitors have several advantages over CRT-based monitors:

• Thin and lightweight: at only 4" - 6" thick and about 60-100 lbs., they’re easy to hang on any wall.

• Very bright: less sensitive to ambient light than most LCD projectors, plasma monitors have the brightness and contrast of CRT-based sets.

• 160° viewing cone: ideal when your room is wide and people may view the monitor from farther off-axis than normal.

• Stable and distortion-free: unaffected by magnetic fields; useful in many applications where CRT monitors or LCD and CRT projectors are problematic. Entire image always in perfect focus, not just in the center, but all the way to the corners.

• Look and feel: plasma somehow looks different--better--than monitors and projectors alike. It's hard to quantify that difference, but most people would say they have more depth and warmth than other types media. They look very, very good.

What are the disadvantages of plasma?

This new technology has several disadvantages worth mentioning.

• Cost: plasma is expensive. For that reason alone, plasma is not for everyone. But prices are coming down, as they do for most new technologies.

• More susceptible to burn-in than CRT monitors. It's not a good medium on which to display a company logo for two or three hours at a time. But with the appropriate precautions, and in some situations a screen saver, you should not expect problems.

• Resolution restrictions: plasma is subject to the same type of resolution problems as LCD or DLP projectors. You'll get the best images when the resolution of your source matches the "true" resolution of the monitor. But, as with LCD, the monitors will incorporate compression or expansion circuitry to automatically resize other resolution sources to match their native resolution, and most people will be very happy with the result. Still, if sharpness is critical for your application and you'll be using a variety of computer sources, you may be better off with a CRT-based unit.

• Doesn't travel well: plasma is not portable. These monitors weigh 60 - 100 pounds and they don't do well if you drop them. If you want to travel with a plasma monitor, plan to invest in a good shipping case.

There's one other rumored "problem" with plasma that turns out not to be true. It has been said by some that plasma units do not have a long lifespan. Actually, the estimated life span for plasma monitors (according to Sony) is about 30,000 hours-- which translates to approximately 15 years at 8 hours a day, 5 days a week (comparable, or maybe a bit better, than a CRT-based monitor).

*Plasmavision™ image, courtesy of Fujitsu General America, Inc.