The application of digital holography for the inspection of microcomponents

Digital Holography is a modem coherent-optical technique that allows the direct acces to the interference phase in holographic interferometry. In contrast to conventional tactile measurement techniques digital holographic interferometry provides full-field access, non-invasivity, high sensitivity and accuracy, high resolution of data points and advanced system performance in order to meet requirements of the underlying numerical or analytical model. The measured interference phase contains the information about the shape of the object under test and/or its deformation after loading. These data can be used to investigate the materials' behaviour of microcomponents. In combination with special loading techniques and physical models of the loading behaviour of the investigated componets some important material parameters such as the Young's modulus, the Poisson ratio and the thermal expansion coefficient of microcomponents can be measured. The paper describes the measuring technology and shows some examples of microcomponent testing.