Abstract
Since the advent of lasers in 1960s, more and more fields of applications have been investigated and developed greatly. Nowadays, various applications of lasers including consumer electronics, display technology or material processing have affected the development of technology and launch a breakthrough in modern optoelectronics. Laser plays an important role in high-precision material processing. It can be used in cutting, laser annealing or laser ablation, etc. In laser applications, it is usually required to modulate laser for beam shaping and beam splitting. However, most lasers possess Gaussian distribution, which is not adequate for uniform processing. Therefore, it is often required to transform laser into top-hat energy distribution with least energy loss as possible. On the other hand, in order to meet the demands for large area processing and high manufacturing efficiency, it is desired to replicate the single top-hat beam into multiple top-hat beams. Beam shaping and beam splitting can be achieved by refraction, reflection or diffraction. The purpose of the thesis is to design diffractive optical elements (DOE) to modulate laser to fulfill above-mentioned concepts. With regards to the fabrication of DOEs, continuous phase modulation is quantized into four-level surface relief pattern. The DOEs are fabricated by using semi-conductor manufacturing technology and UV curing. Then, the DOEs are integrated together and analyzed to realize the multiple top-hat spots for the laser application module.