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Advantages of the lensless Fourier holography setup for the reconstruction of digitally recorded holograms in holographic interferometry are presented. This very simple setup helps to achieve a maximum lateral resolution of the object under investigation. Also, the numerical-reconstruction algorithm is very simple and fast to compute. A mathematical model based on Fourier optics is used to describe discretization effects and to determine the lateral resolution. The recording and the reconstruction processes are regarded as an optical imaging system, and the point-spread function is calculated. Results are verified by an experimental setup for a combined shape and deformation measurement.

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Digital Holography makes it possible to reconstruct the phase distribution of wavefields directly. By application of interferometric technics the observed 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. However, the observed mod2π-interference phase must be unwrapped and the absolute phase values have to be transformed into 3D-coordinates and displacement components. To this purpose a multi-wavelength procedure was developed that avoids the complicated spatial unwrapping procedure. Moreover an adapted calibration technique is used to calculate the metrological data from the distorted phase field. In combination with special loading techniques and physical models of the loading behaviour of componets with beam geometry 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.