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The first plasma displays:
The first plasma screens were shining as early as 1964 at the University of Illinois at Urbana-Champaign, where they were being used as computer terminals. The confronting problem at that time was associated with the clock frequency of the first computers not being able to reproduce flicker free imagery.
A team headed by Donald Blitzer then developed displays where the pixel was fired by a computer impulse, and then kept shining through the mains voltage. They were monochrome (orange) and were incapable of displaying gray shades. For a long while they served a niche market within the military.
Decisive achievements and today's technology:
Today's phosphor-based technology with impulse controlled brightness is largely due to the efforts invested by Plasmaco in the USA (which was later to be taken over by Panasonic), Fujitsu, the NHK laboratory in Tokyo, and the development institute of Japanese televisions. The most decisive achievements were made in the first half of the 1990s.
First suppliers appeared:
NHK invited the Japanese manufacturers to work together in a consortium to develop consumer equipment. A multitude of organizations participated, and from 1996 the first suppliers began to appear: Fujitsu and Pioneer, Hitachi, NEC and Panasonic (Matsushita). In Korea, the first manufacturer was the Daewoo subsidiary Orion, followed by Samsung and LG. Pilot projects were started in Taiwan by two manufacturers but dropped them as LCD became more attractive. A period of consolidation began after the initial wave of engineering effort and investment: Fujitsu and Hitachi combined their activities in the FHP joint venture, and Pioneer took over the plasma unit of NEC.
Plasmatron Technology:
The Plasmatron system (plasma-addresses liquid crystal) was not a true plasma display. This Sony LCD was actually developed by Tektronix and was around for a good ten years. In place of a TFT (Thin-Film Transistor) layer, plasma channels were responsible for the control mechanism to switch the liquid crystal cells between light and dark. Here the diverse conduction properties of plasma compared with gas were well utilized. The technology was flawed when it came to producing larger screen sizes, and anyway, additional manufacturing processes made series or volume production a near impossibility.
Less Light and Heavier:
In the last ten years of product development, many weaknesses or flaws concerned with plasma technology have been successfully eradicated. However, it is also of interest to note that in the same time, some technological areas of LCD technology have moved ahead of plasma. For example, plasma is not as bright, does not have as much contrast in light ambient conditions and the set is heavier.
Pixel Miniaturization and Energy Efficiency:
Along the same lines, another disadvantage associated with plasma is concerned with pixel miniaturization, which is not so easy to accomplish as it is with LCD technology. Energy efficiency is the main culprit, which becomes evident when considering panels offering full HD compatibility. Hence, 42" (107 cm) panels with 768 lines have similar consumption levels to comparable LCD sets, and where the scene's mood is sinister then the consumption values drop even lower.
However, full HD sets require considerably more power. The minimum pixel size also determines the minimum physical screen size so that only 720 lines are available for 42" panels and under, and there aren't any models existing with screen size diagonals below 32" (81 cm).
"False Contour":
A typical plasma screen error is known as "False Contour" and stems from the manner in which the gray tones are generated from individual flashes of light. If a shape traverses the screen, then the impulses overlap with the motion producing additional yet incorrect edges that are visible.
Noise in dark areas of the screen was very noticeable in earlier models, but finer control of the excitation process has helped alleviate the problem, and even screen burn-in is no longer a problem as it once was. Even the screens' operational lifetimes are comparable with those of their main competitors.
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