We analyze a laser dragging process capable of ablating a groove pattern, and producing sophisticated 3D features, on a polycarbonate (PC) sheet through a shaped mask opening. To predict the machined profile during the dragging process, we developed a mathematical model that describes the relationship between laser machining parameters and the produced profile. In addition, we manufacture a miniature lamp lens by varying the mask shape, and dimensions based on the proposed model. The effects of the micro-size lamp lens on light efficiency are investigated. On the other hand, this chapter also introduces a study of sub-micron-structure machining on silicon substrates by a direct writing system using a femtosecond laser with the central wavelength of 800 nm, pulse duration of 120 fs and repetition rate of 1 kHz. Three types of experiment are studied: (1) The effect of photoresist on silicon, (2) The machinability of different orientations of silicon: spike morphologies were observed on all three orientations of silicon substrates without obvious directional difference of these spikes on the different silicon substrates, (3) Micro-structure size and cross-section shape: a numerical model of the machining parameters has been proposed to simulate the cross-section of the micro-structure resulting from a given ablation energy. The predicted shape, determined by simulation, fitted the profile of the cross-section shape well.