The GFP1600 is the tool of choice for general area stress measurement, including area stress in automotive sunroofs. The system can be used with any c-mount lens, including zoom lenses, to conveniently image broad areas and/or close-up details. Combined with a flat-panel illuminator (GFP1600 FPI), full sunroof stress images can be acquired easily, in seconds. Although not as common in sunroofs, the GFP1600 FPI is a powerful tool to document temper patterns. It measures the average stress through the glass and can show imbalance in the tempering, although it does not explicitly provide the surface/skin stress. Examples can be found in sidelite/backlite applications.