Bessel Beam Dielectrics Cutting with Femtosecond Laser in GHz-Burst Mode

Abstract

We report, for the first time to the best of our knowledge, Bessel beam dielectrics cutting with a femtosecond laser in GHz-burst mode. The non-diffractive beam shaping is based on the use of an axicon and allows for cutting glasses up to 1 mm thickness with an excellent cutting quality. Moreover, we present a comparison of the cutting results with the state-of-the-art method, consisting of short MHz-bursts of femtosecond pulses. We further illustrate the influence of the laser beam parameters such as the burst energy and the pitch between consecutive Bessel beams on the machining quality of the cutting plane and provide process windows for both regimes.

High-Power Femtosecond Laser Processing of SiC Ceramics with Optimized Material Removal Rate

“…However, at this value of laser fluence, the material removal rate at 5 MHz was higher than that at other frequencies, which may be attributed to a decrease in the material removal threshold caused by the rise in the temperature of the substrate. As mentioned in previous studies [30,34], an increase in the temperature of the sample surface reduces the material removal threshold at high repetition frequencies and spot overlap ratios, thus resulting in a higher material removal rate. The same phenomenon happened in Figure 7d.…”

“…Furthermore, the laser burst mode for material removal has attracted extensive attention in recent years. Therefore, it is necessary to give a comparative study of conventional single-pulse laser processing and the burst mode strategy [30][31][32]. Consequently, we believe that it is necessary to further study the effects of femtosecond laser fluence on the material removal rate and surface quality of SiC ceramics.…”