if (document.images) {
	img_names = new Array("tp_n01", "tp_n02", "tp_n03");
	img_on = new Array();
	img_off = new Array();
	for (i in img_names) {
		img_on[i]  = new Image();
		img_on[i].src  = "images/" + img_names[i] + "o.gif";
		img_off[i] = new Image();
		img_off[i].src  = "images/" + img_names[i] + ".gif";
	}
}

function offimage(inum) {
	if (document.images) {
		i = inum - 1;
		document.images["img_" + inum].src = img_off[i].src;
	}
}

function onimage(inum) {
	if (document.images) {
		i = inum - 1;
		document.images["img_" + inum].src = img_on[i].src;
	}
}