get screen resolution

I have this problem:
i'd like to get the screen resolution of a visitor of my web page and toghter the $HTTP_REFERER

my idea was to make a page to get the screen res with javascript and to send a var to a php file that contains the $HTTP_REFERER.

But if i make this I always get the refrer of the page that containd my js.

i tryed also to make to 2 php pages
and referin to the second like this

printf("
document.write('<frame src=\"secondfile.php?referer=".$HTTP_REFERER."&resolution='+screen.width+'x'+screen.height+'\">);</script>
");

but in my address bar i'll have exactly

resolution=<script>screen.widthxscreen.height</script>

how can i get away from this trouble?

thanks!

set up screen.width/hieght as a variable in javascript, then use the variables in setting up your referer.