Adverse effects of long term use of LCDs Options

[fast_hamster]

Hi,

I'm a new member, currently studying cognitive science undergrad. I decided to look for a neuroscience forum because I experienced something that I haven't seen in any literature yet. I wouldn't be surprised if this was a widely known phenomenon though.

Ok, so here is what happened. After playing around with a smartphone for two hours continuously, I realized that I should really be preparing for my exams and went back to look at my notes. However, I noticed that I could see a grey shadow on high contrast objects such as letters, formatting frames on webpages etc,. The shadows got quite sharp contours and they appear generally if I look at dark objects on a light background. Shifted downwards from the original consistently. Also, they appear if I look using only one eye.
Also, the effect persists for quite a long time (20mins or so now), but gradually getting weaker.

It's not really surprising to see this kind of thing happening with these LCDs which were most probably never subject to any medical tests (I guess they are mildly hazardous anyways).

Do you know if there is any research on this effect? I was wondering what mechanics might be underlying.