"Now, there are varying degrees of phosphor ignition along the way (the same way a CRT fades). Dissipation begins the moment you turn the set on. After 1000 hours of usage a plasma monitor should measure around 96% of its original brightness, which is barely noticeable to the naked eye. At 15,000 to 20,000 hours the monitor should measure around 80% brightness, or to state is technically, 80% of the original phosphors (gases) are being ignited."
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