Bad to leave android in clock mode?

So I have an android cell phone (the dell streak) I have a dock that I leave the phone in at night. It auto switches to a black screen with green colored numerals to show the time (it moves around the screen every once and a while) so I am wondering if its bad for the phone and or lcd to be left like this all night? Btw i use the phone as my alarm and my regular clock sits behind it.