function doVideo() {
	var w = 800, h = 600;
	if (document.all || document.layers) {
		w = screen.availWidth;
   		h = screen.availHeight;
 	}
	var popW = 340, popH = 350;
	var leftPos = (w-popW)/2, topPos = (h-popH)/2;
	window.open("video.asp","LeesMeer","width="+popW+",height="+popH+",top="+topPos+",left="+leftPos+",scrollbars=no");
}