Google filed an interesting patent in 2012, in which they suggest to reduce the image on a screen when the device is idle. The idea is that when the user is not active, the display size is slowly reduced, until it is invisible. The patent specifically says that this is useful on OLED displays - as it would save power and still present a somewhat useful image to the user.
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Posted: Sep 02,2012 by Ron Mertens
Seems to be a brilliant solution for making OLED-displays much more power efficiency in OLED-displays
because of that OLED-displays with no current is on each subpixel or pixles do not consume any power at all and it is black because of that.