For edge stress measurement in glass
It is a portable instrument which allows quantitative measurement with the Senarmont method of compensation.
Features: The procedure is non destructive, and can be used on both flat and curved glass.
A transparent scale allows measurements to be made at distances of up to 50 mm from the edges of sheets. An adjustable magnifying lens, incorporating a half-field monochromatic green filter (546nm in wavelength) is provided for observing the interference fringes, visible near the edges of the glass, when taking quantitative measurements.
Glass thicknesses of up to 25 millimetre can be measured