@yvanleterrible: Thats why i put "burn in" in "
There is no real data on the subjetc yet. Noone really knows, if a real burn in effect can happen with eink. But its probably nothing like with the old monitors.
But the screen is supposedly degrading with time, so you get less contrast after while.
I noticed this effect strongly on my device after using it several days. After that i seems to stay on the same level.