function screen(){
		var screen = document.getElementById("screen");
		screen.style.visibility = "visible";
		var screen = document.getElementById("screen1");
		screen.style.visibility = "visible";
	}

	function screen_zu(){
		var screen = document.getElementById("screen");
		screen.style.visibility = "hidden";
		var screen = document.getElementById("screen1");
		screen.style.visibility = "hidden";
	}

	function im(i){
		var image = document.getElementById("image");
		var scr = i;
		image.src = "bilder/screen/"+ scr +".jpg";
	}
	
	function sw(s){
		var i = s.title;
		i = parseInt(i);
		var b = document.getElementById("b1");
		var b2 = document.getElementById("b2");
		if(i > 4){
			b.title = (i-1);
		}
		if(i < 7){
			b2.title = (i+1);
		}
		var z = 1;
		for(var x=(i-3); x<=i; x++){
			var im = document.getElementById("s"+z);
			im.src = "bilder/screen/screen_"+x+"_mini.jpg";
			im.title = "screen_"  + x;
			z++;
		}
	}