Event.observe(window, 'load', function ()
{
  Event.observe($('visa-pop'), 'click', function (event)
  {
    Event.stop(event);
    visa_popup();
  });
});

function visa_popup()
{
  var infoWin = window.open('visapop.html', 'Information', 'width=400,height=400,scrollbars=yes,resizable=yes,menubar=no,status=no,toolbar=no,location=no');
  infoWin.focus();
}