The Isodyne technique based on the scattered light scanning from a thin laser beam can be used to obtain the information inside the loaded object at the room temperature nondestructively, so it is a very powerful tech...The Isodyne technique based on the scattered light scanning from a thin laser beam can be used to obtain the information inside the loaded object at the room temperature nondestructively, so it is a very powerful technique in 3D stress analysis. The problems are how to interpret the information and how to get sufficient information from the few interference fringe. Birefringence phase shift technique can distinguish the fringe orders automatically and enrich the information in 256 gray levels between maxim and minim light intensity. The Isodyne birefringence phase shift method with an oblique incidence and equilibrium equation is presented, by which the 3D stresses in the middle plane of a plate with U shape notch are separated successfully. (Edited author abstract) 12 Refs.展开更多
基金The project supported by the National Natural Science Foundation of China under the Grant No.1380345
文摘The Isodyne technique based on the scattered light scanning from a thin laser beam can be used to obtain the information inside the loaded object at the room temperature nondestructively, so it is a very powerful technique in 3D stress analysis. The problems are how to interpret the information and how to get sufficient information from the few interference fringe. Birefringence phase shift technique can distinguish the fringe orders automatically and enrich the information in 256 gray levels between maxim and minim light intensity. The Isodyne birefringence phase shift method with an oblique incidence and equilibrium equation is presented, by which the 3D stresses in the middle plane of a plate with U shape notch are separated successfully. (Edited author abstract) 12 Refs.