This paper gives a review of modern photoelastic technology for residual stress measurement in various glass articles, including glass articles of complicated shape. For residual stress measurement in axisymmetric glass articles, integrated photoelasticity is being used by many glass companies and research laboratories. In case of non‐axisymmetric glass articles of complicated shape, photoelastic tomography is used. As for automotive and architectural glass panels used in buildings, surface stress can be measured with the mirage method. More complete stress analysis can be carried out with the scattered light method. The paper is illustrated by numerous examples.

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The paper describes an algorithm of photoelastic tomography and its application for residual stress measurement in glass articles of complicated shape. The algorithm is based on a linearized solution of the equations of integrated photoelasticity. The problem of tensor field tomography is decomposed into several problems of scalar field tomography for normal stress components of the stress tensor. The method is implemented with an automated polariscope supplied with a rotary stage. Several examples illustrate application of the method.

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A portable scattered light polariscope SCALP has been developed, which permits measurement of the residual stress profile through the thickness of glass panels. At a glass factory strength assessment of glass panels of different thermal treatment was carried out using both residual stress measurement with SCALP and the traditional four-point bending tests. Linear correlation between the residual surface stress and the bending strength was observed. At another glass factory residual stress in glass panels was measured before performing the traditional fragmentation test. The results of the fragmentation test were extremely scattered and had almost no correlation with the values of the residual stress. It is concluded that sufficiently reliable assessment of the strength of glass panels is obtained by measuring the residual stress at the surface.