var _selection = null ;
function HighLightImage(objName, imageName)
{
    if ( _selection == null )
    {
        var obj = document.getElementById(objName);
        var imagePath = "hrImages/MainBackground/";
        obj.src = imagePath + imageName;   
    }
    else
    {
        if ( objName != _selection )
        {
            var obj = document.getElementById(objName);
            var imagePath = "hrImages/MainBackground/";
            obj.src = imagePath + imageName;   
        }
    }
                     
}