A plasma display is made up of many thousands of gas-filled cells that
are sandwiched in between two glass plates, two sets of electrodes, dielectric
material, and protective layers. The
address electrodes are arranged vertically between the rear glass plate and a
protective layer. This structure sits
behind the cells in the rear of the display, with the protective layer in
direct contact with the cells. On the
front side of the display there are horizontal display electrodes that sit in
between a magnesium-oxide (MgO) protective layer and an insulating dielectric
layer. The MgO layer is in direct
contact with the cells and the dielectric layer is in direct contact with the
front glass plate. The horizontal and
vertical electrodes form a grid from which each individual cell can be
accessed. Each individual cell is walled
off from surrounding cells so that activity in one cell does not affect
another. The cell structure is similar
to a honeycomb structure except with rectangular cells.
Introduction
The plasma display panel was invented
at the University of Illinois at Urbana-Champaign by Donald L. Bitzer, H. Gene
Slottow, and graduate student Robert Willson in 1964 for the PLATO Computer
System. The original monochrome (usually orange or green, sometimes yellow)
panels enjoyed a surge of popularity in the early 1970s because the displays
were rugged and needed neither memory nor circuitry to refresh the images. A
long period of sales decline followed in the late 1970s as semiconductor memory
made CRT displays cheaper than plasma displays. Nonetheless, plasma's
relatively large screen size and thin profile made the displays attractive for
high-profile placement such as lobbies and stock exchanges.
In 1983, IBM introduced a 19-inch
orange-on-black monochrome display (model 3290 'information panel') which was
able to show four simultaneous IBM 3270 virtual machine (VM) terminal sessions.
That factory was transferred in 1987 to startup company Plasmaco, which Dr.
Larry F. Weber, one of Dr. Bitzer's students, founded with Stephen Globus, and
James Kehoe, who was the IBM plant manager. In 1992, Fujitsu introduced the
world's first 21-inch full-color display. It was a hybrid, based upon the
plasma display created at the University of Illinois at Urbana-Champaign and
NHK STRL, achieving superior brightness. In 1996, Matsushita Electrical
Industries (Panasonic) purchased Plasmaco, its color AC technology, and its
American factory. In 1997, Pioneer started selling the first plasma television
to the public. In popular culture plasma televisions are often seen around the
home and are being introduced thinner and in greater sizes, in order to try and
compete with projector screens.
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