if(typeof counter != 'undefined'){
     counter.innerHTML = '<img src="Images/counter.php?site='+site+'&amp;ref='+ref+'&amp;screen='+ss+'&amp;display='+d+'" style="width:130px;height:50px;" alt="カウンター" />';
    }else{
     document.write('<img src="Images/counter.php?site='+site+'&amp;ref='+ref+'&amp;screen='+ss+'&amp;display='+d+'" style="width:130px;height:50px;" alt="カウンター" />');
    }