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Deep-pocketed video buffs have complained that their £10,000 plasma
screen TVs can be damaged by bright, high-contrast TV channel logos. These
static images can burn a permanent image into the display—remaining
visible even after the set has been switched off. To answer this, Sony has
incorporated circuitry into the set that continually monitors each part of the
image (US 6313878). If any small area shows no change after 10 minutes, the set
reduces the contrast of the picture to prevent burn. Anyone watching a station
with an overly bright static logo sees a dimmer but safer picture.