I have a Samsung Galaxy S mobile phone, I can't seem to find the dimensions of the screen (apart from looking it up on the internet of course).
But in general: can you somewhere see the correct screen dimensions of a mobile device's screen ?
I don't believe there is a way, which is strange. Maybe because it can't be changed they don't think we need to know?
You can install an app called "Screen Resolution" which will display your phones resolution if you really want to see it on your phone.
Screen&System provides screen resolution (pixels), pixel density (dpi), screen metrics, height, width, and diagonal in centimeters and inches.