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| Plasma Technology |  The concept of plasma technology was born in July of 1964 at the University of Illinois. First plasma screens appeared at the US market towards the end of 1999. The first displays were nothing more than points of light created in laboratory experiments. By the late 60's the plasma technology was developed and improved, it allows the scientists to built geometric shapes. Full color, bright plasma displays became possible owing to the progression in high speed digital processing, materials, and advanced manufacturing technology.
Hundreds of thousands of tiny cells positioned between two plates of glass contains the xenon and neon gas in a plasma television. There are long electrodes between the glass plates, in front of and behind the cells. The address electrodes are contained behind the cells, along the rear glass plate. The transparent display electrodes are mounted in front of the cell, along the front glass plate. These electrodes are surrounded by an insulating dielectric material and covered by a magnesium oxide protective layer. The electrodes crossing paths at a cell are charged by control circuitry, this creates a voltage difference between front and back, leads the gas ionizing and forms a plasma; photons are given off when the gas ions rush to the electrodes and collide.
In a monochrome plasma panel, it is possible to maintain the ionizing state by using a low-level voltage between all the horizontal and vertical electrodes - even after the ionizing voltage is removed. all voltage is removed from a pair of electrodes in order to erase a cell.
In color panels, the back of each cell is covered with a phosphor. The ultraviolet photons emitted by the plasma excite these phosphors to emit colored light.
Every pixel consists of three separate subpixel cells. Every cell has different colored phosphors. One subpixel is red, one subpixel is green and one subpixel is blue. These colors unite to produce the overall color of the pixel, analogous to the "triad" of a shadow-mask CRT. The control system changes the pulses of current flowing through the different cells thousands of times per second and increases or decreases the intensity of each subpixel color to produce billions of different combinations of red, green and blue. In this way, the control system can create most of the visible colors.
Digital television is now rather widespread. It differ sharply from yesterday's TV sets. Thanks to HDTV, DTV, DVD-Video, digital satellite broadcasts and computer video we can experience a digital video revolution today. Plasma display technology is one way to fully enjoy the dramatically improved image quality of all these digital video sources.
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