Screen flashes yellow, sometimes green when trying to wake up or turn on.

[Rahdni]

When I wake up or turn on the phone, the screen flashes green or yellow then goes back to black. Also when i plug in cord to charge, flashes same showing battery then black.
Once screen comes on regularly, phone works fine as long as screen doesn't go to sleep or get turned off.
Sometimes it takes 5 to 60 minutes of pushing power or home button before it eventually comes on correctly. It doesn't seem to be a damaged screen because it seems to work fine once it does come on. Help!