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We proposed a novel method for fabricating polymer compound microlenses (PCMLs) using micro-inkjet technique and subsequent curing process. Two different types of PCMLs with sandwich microstructure (PDMS-Glycerol-PDMS), concave and convex PCMLs,have beendesigned and fabricated in experiments. Convex PCML has two real images and two foci. The concave PCML has one real and one virtual focal planes, whichcan generate one real image and one virtual image respectively. Moreover, the diameter of concave PCML can be controlled by adjusting the curing time and temperature. The proposed method is simple, efficient and suitable for realizing large-scale high numerical aperture PCMLs array, which has potential applications in diverse optical systems such as optical storage and three-dimensional imaging.

Electromagnetic joining technology is an effective technique to join tubes with dissimilar materials. In this paper, a new approach for steel/Al tube parts joined by electromagnetic crimping using a flat coil was investigated. Electromagnetic crimping process experiments with different discharge energies (12, 14, and 16 kJ) and property tests were carried out. Meanwhile, the deformation characteristics of the outer tube under different discharging energies were discussed to study the fittability of the joining zone. The quality of the crimped joint was analyzed by microstructure characterization. The results show that the proposed approach was able to obtain torque joints and was potentially for tubular parts manufacturing. Moreover, higher discharging energy would result in better fittability degree and torque strength but might cause some cracks in the necking area. Combining the results of torsion tests with the microstructure observation, the comprehensive performance of the joint formed under a moderate discharge energy (14 kJ) was optimal.

We proposed taper array in silica glass for beam splitting which was fabricated by water-assisted femtosecond laser direct writing technology and the subsequent heat treatment.We divided the array into many fabricating cells which were executed automatically in sequences as specified by the program that contained the information for the three-dimensional stage movements. Each cell could fabricated a rectangular cylinder. The size and distribution of the rectangular cylinder could be controlled by adjusting the position of the fabricating cells. Then the heat treatment should be used to reshape the rectangular cylinders into taper array. The experimental results show that the taper periodic microstructures in silica glass are uniform and smooth, and the tapers can divide the incident light into beam array. The results demonstrated that the combination of the water-assisted femtosecond laser direct writing technology and the heat treatment is accessible and practical for the high quality micro-optical elements. These micro-optical elements will have potential applications in fluorescence detection and beam splitter.

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