Comment 51 for bug 41994

I have noticed this problem also, since I got my laptop back on Ubuntu 10.10, and it is still a problem on 11.10. The only difference is I am not giving it any input, it wakes up on it's own.

I remember back in 10.10, with a friend, we tried to debug the problem. We first looked at some logs, whenever the screen turned back on, there was a message something like, "X no longer idle". The only reason my friend could think of, for the X server to not be idle is that it received some input. So, we ran the program which shows any input received (might have been xev?), and tested again, but this showed that the system was not receiving any input. So, we were unable to work out why X is would stop being idle (and turn the screen back on).