Fig. 1. Schematic of hydrodynamic groove graphic filling

Fig. 2. Schematic of one-way machining principle of hydrodynamic groove

Fig. 3. Schematics of laser processing and measuring system for hydrodynamic groove

Fig. 4. Schematic of hydrodynamic groove depth measurement

Fig. 5. Experimental results of groove depth at different laser energy densities

Fig. 6. Influence of laser power on groove depth

Fig. 7. Influence of repetition frequency on groove depth

Fig. 8. Influence of scanning speed on groove depth

Fig. 9. Influence of filling space on groove depth

Fig. 10. Influence of number of marking on groove depth