Abstract:The digital image correlation (DIC) method currently suffers from inadequate systematic calibration methods and an underdeveloped metrological traceability system. To address these challenges, this study proposes a novel calibration methodology based on laser interferometry, integrated with a custom-designed optical system for local deformation measurements. Finite element simulations are employed to analyze the stress stiffening effect in strain plates under tensile loading. A coupled thermo-mechanical model is developed via theoretical analysis and experimental validation to quantitatively assess the influence of convective heat transfer on surface strain measurement accuracy. Furthermore, an Abbe error compensation mechanism is implemented to effectively mitigate nonlinear measurement errors induced by microscale bending during loading. A comprehensive uncertainty analysis is conducted to evaluate both standard uncertainty components and the overall measurement uncertainty. Experimental results demonstrate that the proposed calibration device reduces the uncertainty in standard strain field measurements to the range of 1.9% to 0.83%, offering a critical advancement toward establishing a traceable calibration framework for DIC-based strain measurement systems.