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Strain is expected to have an important role in future devices based on micro-systems.Different methods have been used to engineer strain in devices,leading to complex strain distributions.However, it has proved elusive in practice to measure the strain, especially the normal and shear components, directly and wireless with micro/submicro solutions.Owing to the investigating progresses of carbon nanotube (CNT) recently, it is well known that CNT has outstanding mechanical characteristics, its Raman shift is very sensitive to axial deformation, and its polarized resonant Raman behaves as the antenna effect.All these properties make CNT film, namely the so-called buckypaper, a potentially robust and wireless strain gauge applicable for the measurement of strain components.In this work, we present a modelling and experimental study of buckypaper strain gauge in terms of micro-Raman spectroscopy.The theoretical model of buckypaper strain gauge is developed by applying the resonant and polarized Raman properties of CNTs and quantificationally calculating the synthetic contributions from individual CNTs in random directions to the entire Raman spectrum.The proposed model provides an analytic relationship between the in-plane strain components to be measured and the Raman-shift increment detected through polarized Raman tests.Based on this model, we introduce a novel noncontact technique of strain measurement named Raman Strain Rosette, which detects the Raman-shift increments of the spectra from a same sampling spot with three different polarized directions.This proposed technique is applied in several experiments to confirm the validity of the buckypaper strain gauge in this work.The experimental results verifies that Raman Strain Rosette is practicable to quantitative measuring all the in-plane components of the strain tensor (including both normal and shear strains) and it is further applicable to achieving the strain fields through Raman mapping.