Abstract: A method and apparatus for measuring the temperature and/or displacement of a glass ribbon formed in a downdraw glass forming process, and measured across width of the ribbon. Temperature and displacement measurements may advantageously be performed simultaneously with a high degree of spatial resolution by a measurement assembly which does not contact the glass ribbon. Temperature measurements may be performed across substantially the entire width of the ribbon. Data developed by the measurement assembly may be used in an automated feedback loop to control the glass ribbon forming conditions.