A simple approach to photoelastic calibration of glass using digital photoelasticity

Quantification of residual stresses in glass articles necessitates the knowledge of photoelastic constant of the glass material. The recent developments in digital photoelasticity have increased its applicability in residual stress analysis of glass. In this paper, photoelastic calibration of the glass material has been performed using the carrier fringe method (CFM) and phase shifting technique (PST) in digital photoelasticity. The retardations measured by both of these techniques are used for the calculation of photoelastic constant of the glass material and they were found to be in good agreement with each other. Calibration of glass by CFM is recommended for industrial applications since it requires only a few images as compared to PST.