问Typeahead，我无法获取图像

EN

$('input.typeahead').typeahead({
source: function(query, process){
  $.ajax({
    url : "http://localhost/centrix/tasks/getRelatedAccount",
    type : 'POST',
    data : 'query='+query,
    dataType : 'JSON',
    async : true,
    success : function(data){
      return process(data.contact_name);
    }
  });
},
highlighter: function(data){
    html = '<div class="typeahead">';
    html += '<div class="media"><a class="pull-left" href="#"><img class="img-circle img-xs" src='+data.contact_name+' /></a>';
    html += '<div class="media-body">';
    html += '<p class="media-heading">'+data.contact_name+'</p>';
    html += '</div>';
    html += '</div>';
    return html;
  }
});