A serious Problem occured on the screen of my 3gs!!!!!!

Question

I bought my 3gs about 1 month ago.At first,I got good experience and learned the meaning of 's'.But then I found a serious problem.It happens ONLY JUST the moment I reopen the screen if I used the screen for a while.About 3 mm near to the edge of the screen it would appear some green lines(a small green square in the screen).I think this might be sometihing like afterimages.The longer I used the screen,the loooooooooonger the green lines will be.The most strange thing is if I don't use the screen for about more than 1 hour,it will turn back to normal.But after about 1 or 2 min it is bad again!
When I am using the screen not open the screen it acts as normal one's,everything is good.
Could any guy tell me the reason of this phenomenon?
Firmware:iPhone OS 3.1.2

Answer 1

You can try the basics from the manual:
Restart, reset, restore.
If this doesn't help then you can take it to the Apple Store, or whomever provides service in your country and they will replace is it is defective.