you can turn on safe mode by press and hold power key while power options appears on the screen. hold the power off option and you can see a green tick on the screen. then your device will restarted. that's all, safe mode is active on your phone. to turn it off just restart your device or swipe down the notification panel , you will find turn off safe mode option there ,click on it and your device restarted.
Please perform the below mentioned steps to resolve the issue:
* Adjust the brightness Settings > Display > Adjust the brightness.
For further assistance, register your concern in Samsung Members Application (Open Samsung Members Application > Get help > Send Feedback > Error report/Ask questions).
