function winopen(image_no,screenW,screenH,WindName){
   
   win = window.open("sluzby.htm", WindName, "toolbar=no,location=no,directories=no,status=no, menubar=no, resizable=yes,copyhistory=no, width="+screenW+", height="+screenH+", left="+((screen.Width-screenW) / 2)+", top=5");
   win.focus();
    }