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Origami and kirigami are effective approaches to fabricate the lightweight cellular metamaterials with extraordinary mechanical properties. However, the novel designs of such metamaterials are still limited. In this paper, a novel metamaterial similar to the typical Kelvin foams is proposed and fabricated via the origami and kirigami methods, and its mechanical properties are investigated. The quasi-static compression tests are first conducted to analyze the deformation characteristics and stress-strain responses. Numerical simulations are then carried out to simulate the tests. Furthermore, two methods including adjusting the wall thickness and introducing opening are adopted to alter the relative density of the metamaterials, and their influences on the plateau stress and specific energy absorption (SEA) are explored. Finally, analytical studies are conducted to predict the plateau stress, and good agreements between the analytical, numerical, and experimental results are obtained. Results reveal that the kinetic energy is primarily dissipated by unfolding the constitutive elements along the creases, and three typical stages are generated in the stress-strain curves. Increasing the wall thickness significantly improves

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In this Letter, we present a new, to the best of our knowledge, form of single-exposure quantitative phase microscopy based on the phase retrieval method by recording the band-limited image and its Fourier image simultaneously. Applying the intrinsic physical constraints of microscopy systems in the phase retrieval algorithm, we remove the inherent ambiguities of the reconstruction and achieve a rapid iterative convergence. In particular, this system does not require tight support of the object and the oversampling needed in coherent diffraction imaging. We have demonstrated that, in both simulations and experiments, the phase can be rapidly retrieved from a single-exposure measurement using our algorithm. The presented phase microscopy provides a promising technique for real-time quantitative biological imaging.