function openNewWindow(url,height,width,menubar,scrollbars, resizable)

{

  var topMargin = screen.height/2 - (height/2);

  var leftMargin = screen.width/2 - (width/2);

  

  window.open( url, '', 'menubar=' + menubar + ', scrollbars=' + scrollbars + ', resizable=' + resizable + ', width=' + width + ', height=' + height + ', left=' + leftMargin + ', top=' + topMargin );

}



//  <a href="javascript:;" onMouseUp="openNewWindow(url, height, width, menubar=yes/no, scrollbars=yes/no, resizable=yes/no);">