var newWindow = null;  // used to load images

function CloseCurrentWindow() {
	if (newWindow != null && !newWindow.closed){
		newWindow.close();
	}
}

function PopUp(insertLink) {
    
    CloseCurrentWindow();
    
	newWindow = window.open(insertLink, "", 
	"toolbar=0," + 
	"directories=0," +
	"width=" + (window.screen.availWidth * 4 / 5) + "," +
	"height=" + (window.screen.availHeight * 4 / 5) + "," +
	"left=" + (parent.screen.availWidth / 10) + "," +
	"top=" + (window.screen.availHeight / 10) + "," +
	"scrollbars=1," +
	"resizable=1");

	if(newWindow != null && newWindow.opener == null) {
		newWindow.opener = window;
	}
	
    return false;
}