A dead pixel is a small spot on the screen which is permanently black, no matter what is being shown. It occurs when the pixel can no longer receive or respond to an electrical signal, typically due to a problem with the transistor, the device that controls the pixel. Each screen contains millions of pixels; an individual fault can show up as a dark spot. Dead pixels may occur as a result of manufacturing, ageing or physical damage to the display. When the pixel becomes “dead”, it will not emit light whatsoever, and thus it will stand out clearly on bright backgrounds.
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