Study on flat-top shaping technology in picosecond laser micro- machining

In order to achieve the uniform picosecond laser micro-machining effect, this study carries out the research of shaping the original incident Gaussian beam into a micron-level flat-top beam at the focal position. Based on the principle of diffractive optics, the phase distribution of the shaping element is calculated which meets the micron-level flat-top beam output requirements and the verification of the shaping effect after transforming through the phase distribution is simulated. When the simulated output beam distribution meets the design requirements, the shaping elements is manufactured. Finally, the shaping element is used in a picosecond laser micro-scribing experiment and the scribing effect is analyzed. The final experimental results show that the picosecond laser micro-scribing test is carried out with the shaped flat-top beam, and the uniform scribing effect is obtained which satisfies the design requirements.