function affiche_img_centre()
{
document.getElementById('plan_central').innerHTML='<img  onclick="supr_img_centre();" src="../images/plan_essec.gif"><a style="position:relative;left:-55px;top:-380px;" href="#" onclick="supr_img_centre();return false;"><strong>Fermer</strong> </a><br /><a style="position:relative;left:+530px;top:-25px;" href="#" onclick="javascript:imprimer();return false;">Imprimer</a>';
}
function supr_img_centre()
{
document.getElementById('plan_central').innerHTML='';
}

function imprimer(){ 

var fenetre=window.open("../images/plan_essec.gif");
fenetre.print(); 

}