eugenio When I first got my Dasung, I had eyestrain but then I figured out what was going on.
First off, you need your work area WAY brighter when using an e-reader. Whatever you have your current room lighting at to watch an LED monitor, you need to double that. I even have a lamp aimed directly at the monitor.
Next, I use mine on the mode "M2" which has less greyscale. The max greyscale mode gives me eyestrain.
I now use this monitor for hours. And although it's not perfect, the minor eyestrain I get from it is NORMAL eyestrain like you would get from reading too much. It's not like the LED eyestrain which causes all kinds of pain and cognitive issues.
So my two tips for e-readers are. Use the most black and white mode that they have. Work in a very well it room. Use larger font sizes than you normally would.