if(document.images){
	img_data = new Array(
		"tess_b_navi01","tess_b_navi02","tess_b_navi03","tess_b_navi04","tess_b_navi05","tess_b_navi06","tess_b_navi07","tess_b_navi08","tess_b_navi09","tess_b_navi10","tess_b_navi11","tess_b_navi12","tess_b_navi13","tess_b_navi14"
	);
	img_navi_on = new Array();
	img_navi_off = new Array();

	for(i in img_data){
	img_navi_on[i] = new Image();
	img_navi_on[i].src = "./images/" + img_data[i] + "a.gif";
	img_navi_off[i] = new Image();
	img_navi_off[i].src = "./images/" + img_data[i] + ".gif";
	}
}

function offimage_navi(i) {
	if (document.images) {
		document.images["img_navi" + i].src = img_navi_off[i].src;
	}
}

function onimage_navi(i) {
	if (document.images) {
		document.images["img_navi" + i].src = img_navi_on[i].src;
	}
}