Precision glass molding is a revolutionary technology for achieving high precision and efficient manufacturing of glass aspheric lenses. The material properties of glass, including elastic modulus and viscosity, are highly dependent on temperature fluctuations. This paper aims to investigate the effect of elastic modulus on the high-temperature viscoelasticity of glass and the accuracy of the finite element simulation of the molding process for glass aspheric lenses. The high-temperature elastic modulus of D-ZK3L glass is experimentally measured and combined with the glass cylinder compression creep curve to calculate the high temperature viscoelasticity of D-ZK3L. Three groups of viscoelastic parameters are obtained. Based on this, the molding process of the molded aspheric lens is simulated by the nonlinear finite element method (FEM). The surface curves of lenses obtained by simulation and theoretical analyses are consistent. The simulation results obtained at different initial elastic modulus values indicate that the elastic modulus has a great influence on the precision of the FEM-based molding process of glass aspheric lenses.

For small aspherical molds, it is difficult for the existing polishing method to take into account the correction of the surface error and the control of the uniformity of the surface roughness (SR) distribution, because the polishing tool is always larger than the small mold. Therefore, we used viscoelastic polyester fiber cloth to wrap the small steel ball as a polishing tool to adapt to the surface shape change of the aspherical mold, and designed a semi-flexible small polishing disc tool with microstructure, which can better adapt to the curvature change of aspherical surface and obtain better SR Ra. At the same time, a combined polishing method of constant speed and variable speed for screw feed was proposed to improve the uniformity of SR distribution in the paper. Then, a series of theoretical analysis and experimental verification were carried out in this paper to predict the tool influence function (TIF) of the two polishing tools and the effectiveness of the combined polishing method. In the experiment, a TIF bandwidth of about 0.46 mm was obtained with a small spherical polishing tool, which favors the surface shape correction of the small aspherical mold. The experiment of uniform removal with a small polishing disc tool was carried out to quickly reduce the Ra. Finally, the surface quality of the aspherical mold was effectively improved, combined with the constant speed and variable speed polishing modes of screw feed of the small spherical polishing tool and the smoothing effect of the small polishing disc tool. The peak valley (PV) of two small aspherical molds with an optical effective diameter less than 13 mm converged from 0.3572 μm and 0.2075 μm to 0.1282 μm and 0.071 μm, respectively. At the same time, the SR dispersion coefficient was reduced from 27.9% and 41.6% to 14.2% and 12.7%, respectively. The study provides a good solution for the surface quality control of small aspherical molds.

Background: Microfluidic channels have been widely applied in biomedicine and microelectronics. However, the manufacturing methods of microfluidic channel devices, such as photolithography, three-dimensional printing and Melt-electrospinning direct writing (MEDW), have the problem of high cost and complex process, which still can't reach a sub-micron scale stably. Method: To improve the resolution of microfluidic channels, we developed a simple and flexible method to fabricate polydimethylsiloxane (PDMS) submicrofluidic channels. It depends on the following steps: (1) Direct Writing Polyethylene oxide (PEO) nanofiber by Near-field Electrospinning (NFES). (2) Packaging the nanofiber with PDMS. (3) Obtaining the PDMS submicrofluidic channel by inverted mode of PEO nanofiber. Results: According to the result of the experiment, nanofiber can be stably prepared under the following conditions, the electrode-to-collector distance of 3.0 mm, the voltage of 1.7 KV, the collector moving speed of 80mm/s and the mixed solutions of ethanol and deionized water (1:1). Finally, the PDMS submicrofluidic channel was manufactured by NFES and PDMS molding technique, and the diameter of the channel was 0.84±0.08 μm. Conclusion: The result verified the rationality of that method. In addition, the method can be easily integrated with high resolution channels for various usages, such as microelectronics, micro electro mechanical systems, and biomedical.