In traditional diamond cutting, the cutting force is usually large and it will affect tool life and machining quality. Elliptical vibration cutting (EVC) as one of the ultra-precision machining technologies has a lot of advantages, such as reduces cutting force, extend tool life and so on. It’s difficult to predict the transient cutting force of EVC due to its unique elliptical motion trajectory. Study on chip formation will helpfully to predict cutting force. The geometric feature of chip has important effects on cutting force, however, few scholars have studied the chip formation. In order to investigate the time-varying cutting force of EVC, the geometric feature model of chip is established based on analysis of chip formation, and the effects of cutting parameters on the geometric feature of chip are analyzed. To predict transient force quickly and effectively, the geometric feature of chip is introduced into the cutting force model. The calculated results show that the error between the predicted cutting force in this paper and that in the literature is less than 2%, which proves its feasibility.

Microlens arrays have been widely used in the fields of micro-optics because of the advantages of their high diffraction efficiency, high fill factor, and wide operating band. However, the microlens array still has problems with its smaller field of view (FOV) and lower utilization of light energy. In this paper, a 3D compound eye system consisting of a microlens array and a pinhole array was designed according to the optical principle of insect compound eye. The artificial compound eye structure was processed in two-photon polymerization processing technology. Ray tracing and optical system simulation of the designed artificial compound eye structure were performed. The results showed that the artificial compound eye structure had a wider FOV and higher light energy utilization than a conventional 2D microlens array. This thesis may lay a theoretical foundation for the structural optimization design of microlens arrays.

Slicing reference data and adaptive slicing algorithm are the key issues to find out appropriate layer thicknesses of three-dimensional (3D) microstructures with free-form surface in two photon polymerization (TPP). In the present work, an adaptive slicing method (ASM) was proposed to improve the fabricating efficiency of 3D microstructures with free-form surface in TPP microfabrication. In the proposed method, slicing reference data were obtained by intersecting a series of vertical planes with the triangular patch format along characteristic directions. Maximum acceptable chordal height played a role as judging criteria to obtain appropriate layer thicknesses. What’s more, typical 3D microstructures with free-form surfaces were fabricated with uniform slicing method (USM) and the proposed ASM, respectively. The comparison results showed that the proposed method effectively improved fabricating efficiency, guaranteeing an acceptable surface quality at the same time. This work was expected to provide references for improving fabrication efficiency of complex 3D microstructures in TPP.