//erster wechsel
         normal1 = new Image();
         normal1.src = "images/start_n.gif";
         highlight1 = new Image();
         highlight1.src = "images/start_h.gif";

         //zweiter wechsel
         normal2 = new Image();
         normal2.src = "images/firma_n.gif";
         highlight2 = new Image();
         highlight2.src = "images/firma_h.gif";

         //dritter wechsel
         normal3 = new Image();
         normal3.src = "images/raum_n.gif";
         highlight3 = new Image();
         highlight3.src = "images/raum_h.gif";

         //vierter wechsel
         normal4 = new Image();
         normal4.src = "images/prod_n.gif";
         highlight4 = new Image();
         highlight4.src = "images/prod_h.gif";

         //fünfter wechsel
         normal5 = new Image();
         normal5.src = "images/ref_n.gif";
         highlight5 = new Image();
         highlight5.src = "images/ref_h.gif";

         //sechster wechsel
         normal6 = new Image();
         normal6.src = "images/gut_n.gif";
         highlight6 = new Image();
         highlight6.src = "images/gut_h.gif";

         function bildwechsel (bildnr, bildobjekt) {
         window.document.images[bildnr].src = bildobjekt.src;
         }