// JavaScript Document
// =======================================
// set the following variables
// =======================================

function Abrir_Ventana(theURL,w,h,winName) { 

var windowprops ="top=" + (screen.height - h) / 2 + ",left=" + (screen.width - w )/ 2 + ",toolbar=no,location=no,status=no, menubar=no,scrollbars=yes, resizable=no,width=" + w + ",height=" + h;

window.open(theURL,winName,windowprops); 
}