html table 表头 分割斜线

<HTML>
<HEAD>
<TITLE>1</TITLE>
<META NAME="Generator" CONTENT="EditPlus">
        <META NAME="Author" CONTENT="">
                <META NAME="Keywords" CONTENT="">
                        <META NAME="Description" CONTENT="">
</HEAD>
<script Language="javascript">
        function a(x, y, color) {
                document.write("<img  
                                + (x + 20) + "; top: " + (y + 20) + ";background-color: "
                                + color + "' src='px.gif' width=1 height=1>")
        }
</script>
<body leftmargin=20 topmargin=20>
        <TABLE 00aaaa" cellspacing="1" width=100>
                <TR bgcolor="FFFFFF">
                        <TH  height='50' width=10%>
                                <div >
                                        <table border=0 width=100%>
                                                <tr>
                                                        <th valign='middle' align='right'
                                                                >sector</th>
                                                </tr>
                                                <tr>
                                                        <th valign='middle' align='left'
                                                                >region</th>
                                                </tr>
                                        </table>
                                </div>
                        </TH>
                        
                </TR>
        </TABLE>
        <script>
                function line(x1, y1, x2, y2, color) {
                        var tmp
                        if (x1 >= x2) {
                                tmp = x1;
                                x1 = x2;
                                x2 = tmp;
                                tmp = y1;
                                y1 = y2;
                                y2 = tmp;
                        }
                        for (var i = x1; i <= x2; i++) {
                                x = i;
                                y = (y2 - y1) / (x2 - x1) * (x - x1) + y1;
                                a(x, y, color);
                        }
                } 
                //line(1,1,100,100,"000000"); 
                line(td1.offsetLeft,td1.offsetTop,td1.offsetLeft+td1.offsetWidth,td1.offsetTop+td1.offsetHeight,'#FFFFFF')
        </script>
</BODY>
</HTML>