This paper discusses a technique for determining the wavefront deformation from residual stresses in large blanks of optical glasses. The technique explained here, unlike classical interference techniques, is economical because the defects responsible for the appearance of the deformation of a plane wavefront can be independently determined.
V. S. Doladugina, "Technique for estimating wavefront deformation when monitoring the homogeneity of large blanks of optical glasses," J. Opt. Technol. 70, 120-124 (2003)