<script>
function AbreVentana(var1,var2,var3)
{
window.open('captura2.php?&var1='+var1+"&var2="+var2+"&var3="+var3,'wPopup','toolbars=no,scrollbars=yes,resizable=yes');
}
</script>
<input type="button" name="rute" value="Prueba" class="button" onClick="AbreVentana('valor1','valor2','valor3')">