function displayWindow( theURL, winName, width, height, features) { 
            var window_width = width;
            var window_height = height;
            var newfeatures= features;
            var window_top = (screen.height-window_height)/2;
            var window_left = (screen.width-window_width)/2;
            newWindow=window.open(''+ theURL + '',''+ winName + '','width=' + window_width + ',height=' + window_height + ',top=' + window_top + ',left=' + window_left + ',features=' + newfeatures + '');
            newWindow.focus();
        }