如何使用JavaScript打开一个新窗口？

<script language="javascript">
function winpopup(url)
{
popwin=window.open(url,'','toolbar=no,location=no,directories=no,+status=no,menubar=no,scrollbars=no,+resizable=yes,width=670,height=500,left=120,top=120');
}

//打开一个子窗口,并关闭母窗口
winpopup("index1.html");
window.opener=null;
window.close();
</script>