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In this paper, mechanical experiments with a low-cost interferometry set-up are presented. The set-up is suitable for an undergraduate laboratory where optical equipment is absent. The arrangement consists of two planes of illumination, allowing the measurement of the two perpendicular in-plane displacement directions. An axial load was applied on three different metals, and the longitudinal and transversal displacements were measured sequentially. A digital camera was used to acquire the images of the different states of load of the illuminated area. A personal computer was used to perform the digital subtraction of the images to obtain the fringe correlations, which are needed to calculate the displacements. Finally, Young’s modulus and Poisson’s ratio of the metals were calculated using the displacement data.

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New data of creep and viscoelastic Poisson’s ratio, ν(t), of five engineering elastomers (Ethylene Propylene-Diene Monomer, Flouroelastomer (Viton®), nitrile butadiene rubber, silicone rubber and neoprene/chloroprene rubber) at different stress (200, 400 and 600 kPa) and temperature (25, 50 and 80 °C) are presented. The ν(t) was characterized through an experimental methodological approach based on creep testing (30 min) and strain (axial and transverse) measurements by digital image correlation. Initially, creep behavior in axial and transverse directions was characterized for each elastomer and condition, and then each creep curve was fitted to a four-element creep model to obtain the corresponding functions. The obtained functions were used to estimate ν(t) for prolonged times (300 h) through a convolution equation. Overall, the characterization was achieved for the five elastomers results exhibiting ν(t) increasing with temperature and time from about 0.3 (for short-term loading) to reach and stabilize at about 0.48 (for long-term loading).