Contour Mapping of Dynamic Stress Distributions by Novel Polarization Interferometry

A novel method for contour-mapping principal stress distributions is described. In the polarimeter developed, a reference beam of light consists of the two orthogonal linearly polarized components that interfere with their counterpart orthogonal components of an elliptically polarized signal beam of light. Two crossed interference patterns are formed over a MOS TV camera so that the significant parameters for determining a principal stress distribution can be recorded in a computer. The major advantage is that not only each of the two principal stresses but also the principal stress-difference can be independently determined, and no use of any optical component for polarization alignment makes it possible to follow a rapid change in stress distribution within the maximum frame rate 2066 s of the MOS TV camera. 1