Stress Measurement and Defect Identification of Optical Components Based on Digital Holographic Photoelasticity

Abstract To realize defect detection and locate the abnormal areas of optical components, we propose a high-sensitivity detection method based on the principle of digital holographic photoelasticity measurement. First, holograms are acquired before and after external force loading. Then, the complex amplitude is reconstructed, and the phase difference is calculated accordingly. Variables concerning birefringence are solved by obtaining multiple groups of holograms with different reference polarization directions and constructing a ratio function containing only the interference light intensity. Principal stress is calculated after external force loading. The proposed method can be applied to the detection of glass surface cracks, internal holes, and damage, and the reliability and performance of high-powered laser optical components can be guaranteed.