Как установить JSON_UNESCAPED_UNICODE в JsonModel?

namespace Application\Controller;

use Zend\Mvc\Controller\AbstractActionController;
use Zend\View\Model\JsonModel;

class AjaxController extends AbstractActionController
{
    public function indexAction()
    {
        $json = new JsonModel(array(
            'html' => 'тест'
        ));

        return $json;
    }
}