var imgWindow = null;
function showImage(url, caption) {
if (imgWindow) {
imgWindow.close();
}
imgWindow = window.open(url, "Image", "width=420,height=520,scrollbars=no,toolbar=no,location=no,directories=no,status=no,menubar=no");
imgWindow.document.write("Image![](" + url + ")
" + caption + "
Close window");
imgWindow.document.close();
}