function $tab() {
  var elements = new Array();

  for (var i = 0; i < arguments.length; i++) {
    var element = arguments[i];
    if (typeof element == 'string') {
      element = document.getElementById(element);
    }

    if (arguments.length == 1) {return element;}

    elements.push(element);
  }

  return elements;
}

function change_tab(){
	if(nn>3) nn=1
	setTimeout('setFocus1('+nn+')',4000);
	nn++;
	tt=setTimeout('change_tab()',4000);
}
function setFocus1(i){
	selectLayer1(i);
}
function selectLayer1(i){
	var s1 = $tab("focusPic1").style;
	var s2 = $tab("focusPic2").style;
	var s3 = $tab("focusPic3").style;
	var f1 = $tab("focusPic1nav").style;
	var f2 = $tab("focusPic2nav").style;
	var f3 = $tab("focusPic3nav").style;
switch(i)
{
case 1:
	s1.display="block";
	s2.display="none";
	s3.display="none";
	f1.display="block";
	f2.display="none";
	f3.display="none";
break;
case 2:
	s1.display="none";
	s2.display="block";
	s3.display="none";
	f1.display="none";
	f2.display="block";
	f3.display="none";
break;
case 3:
	s1.display="none";
	s2.display="none";
	s3.display="block";
	f1.display="none";
	f2.display="none";
	f3.display="block";
break;
case 4:
	s1.display="none";
	s2.display="none";
	s3.display="none";
	f1.display="none";
	f2.display="none";
	f3.display="none";
break;
}
}