function new_win(url, titel, breite, hoehe)
{
    var breite = breite;
    var hoehe = hoehe;
    
    var links = screen.width/2 - breite/2;
    var oben = screen.height/2 - hoehe/2;

  MeinFenster = window.open(url, titel, "location=no,dependent=yes,toolbar=no,status=no,scrollbars=yes,resizable=no,width=" + breite + ",height=" + hoehe + ",left=" + links + ",top=" + 200);

  MeinFenster.focus();

}