How to access scanner from silverlight?

private void Button_Click_1(object sender, RoutedEventArgs e)
      {
          try
          {
              using (dynamic CommonDialog = AutomationFactory.CreateObject("WIA.CommonDialog"))
              {
                  dynamic imageFile = CommonDialog.ShowAcquireImage();
                  if (imageFile != null)
                  {
                      if (!Directory.Exists("D:\\ScanImage"))
                      {
                          Directory.CreateDirectory("D:\\ScanImage");
                      }
                      string filePath = string.Format("D:\\ScanImage\\{0}.jpg", Guid.NewGuid());
                      imageFile.SaveFile(filePath);
                  }
              }
          }
          catch (System.Runtime.InteropServices.COMException ex)
          {
              if (ex.ErrorCode == -2145320939)
              {
                  MessageBox.Show("Could not find an attached scanner.", "Scanner Error", MessageBoxButton.OK);
              }
              else
              {
                  MessageBox.Show(ex.Message, "Scanner Error", MessageBoxButton.OK);
              }
          }

      }