var mems_1=new Image();
    mems_1.src="images/mems_1.gif";
var mems_2=new Image();
    mems_2.src="images/mems_2.gif";

var evap_1=new Image();
    evap_1.src="images/evap_1.gif";
var evap_2=new Image();
    evap_2.src="images/evap_2.gif";

var scan_1=new Image();
    scan_1.src="images/scan_1.gif";
var scan_2=new Image();
    scan_2.src="images/scan_2.gif";

var kelv_1=new Image();
    kelv_1.src="images/kelv_1.gif";
var kelv_2=new Image();
    kelv_2.src="images/kelv_2.gif";

var mate_1=new Image();
    mate_1.src="images/mate_1.gif";
var mate_2=new Image();
    mate_2.src="images/mate_2.gif";

var lase_1=new Image();
    lase_1.src="images/lase_1.gif";
var lase_2=new Image();
    lase_2.src="images/lase_2.gif";

var cont_1=new Image();
    cont_1.src="images/cont_1.gif";
var cont_2=new Image();
    cont_2.src="images/cont_2.gif";

var home_1=new Image();
    home_1.src="images/home_1.gif";
var home_2=new Image();
    home_2.src="images/home_2.gif";

function zeige(bname,bquelle)
{
   document.images[bname].src=eval(bquelle+".src");
}