Was watching a vid on the GS2 and this also works on the Infuse.
Hold down your finger on the area where the notification bar is, hold it down.
While holding down your finger slide it right and left, this will increase and decrease your screen brightness if you have Auto Brightness OFF in setting.
Hold down your finger on the area where the notification bar is, hold it down.
While holding down your finger slide it right and left, this will increase and decrease your screen brightness if you have Auto Brightness OFF in setting.