어두워짐 방지 (screen full wake up)

PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE); 
PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.ACQUIRE_CAUSES_WAKEUP | PowerManager.SCREEN_BRIGHT_WAKE_LOCK, "screen"); 
wl.acquire(); 
//     ..screen will stay on during this section.. 
//wl.release();

<uses-permission android:name="android.permission.WAKE_LOCK"/>