After using the phone (Samsung S4), when I leave the phone alone, it will stay at normal brightness for a while then it will dim (lower brightness) for about 5 seconds then the whole screen will turn black (sleep).

I want to disable the dim. How can I do it? I want it from normal brightness to turn black (sleep).

Thanks


(It is irritating during the dim because I can only press the screen to make phone to return to normal brightness and I tend to press wrong stuff as screen is dimmed, or no empty area to press. Anything pressed on screen will still take effect but I actually do not want to press anything. When it is black I can use power key to turn on again to normal brightness without pressing screen.)

 

Anyone knows?