Generate PDF using jquery ajax

i am working with phalcon php framework. I want to send data displayed in a div tag(it is a result of a search)to controller function, and controller will generate pdf file. But, pdf file is not generating. Here is my view:

  var imenica = "Ja se zovem Nedim Omerbegovic";
       $.ajax({
        url: '<?php echo  $this->url->get("test/creatingpdf");?>',
        type: 'POST',
        dataType: '',
        data: {imenica:imenica},
        success: function(data){
            alert(data);
            } ,
            error: function(){
                alert("Greska");
            }

    });
});

and here is code for controller:

public function creatingpdfAction(){
    $this->view->disable();
    $string =$_POST['imenica'];
    $this->view->setVars(array('ime'=>$string));

          $loader = new \Phalcon\Loader();
    $loader->registerClasses(
     array(
    "mpdf"=> "C:/wamp/www/phalcon1/mpdf/mpdf.php"
 )
 );

    $loader->register();
    //$string = "Ja se zovem Nedim Omerbegovic";
    $view = new \Phalcon\Mvc\View();
    $view->setViewsDir('../app/views/');
    $cont = $this->view->getRender('test', 'creatingpdf');
    //generisanje pdf dokumenta
    $pdf = new mpdf();
    $pdf->WriteHTML($cont, 2);
    $br = rand(0,100000);
    $ispis = "Pobjeda Rudet-Izvjestaj-".$br;
    $pdf->Output($ispis, 'I');
  }

How can i see generated pdf file in this way of warking. Please, if anyone knows help me.