You might have the air gesture turned on. This allows you to move your hand over the phone and it turns the screen on for a few seconds so you can see if you have any msgs, notifications, check the time etc without having to physically touch the phone. (At least this is my novice explanation of it).
When I first got my phone I didn't know what was causing my screen to turn on until one day I noticed it was when I reached over the phone and so my hand went over the sensor. After learning more about the phones functions I saw that it was called "air gesture" I've included a wee pic of where it shows up, you can turn it off if it's bugging you.
Hope this helps a wee bit,
Sarks.
Sent from my SM-N900V using AC Forums mobile app
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01-31-2014 03:31 PM