var Fenster = null;

function openWindow(meineSeite,meinName,w,h){

    LeftPosition = (screen.width) ? (screen.width - w) / 2 : 0;
    TopPosition = (screen.height) ? (screen.height - h) / 4 : 0;

    settings ='height='+h+',width='+w+',top='+TopPosition+',left='+LeftPosition+',scrollbars=0,resizable'

    Fenster = window.open(meineSeite,meinName,settings)
}

function closeWindow() {
    window.close();
}