function imagezoom(w,h,url) {
   var Fensteroptionen = "toolbar=0,scrollbars=1,location=0,statusbar=0,menubar=0,resizable=1";
   var popupWindow = window.open(url, 'Imagezoom', Fensteroptionen + ',width=' + w + ',height=' + h);
   var focus = popupWindow.focus();
}