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Abstract. Laser scanning devices are indispensable for material surface treatment, laser drilling, and laser marking; due to the limited scanning speed, the traditional galvanometer scanning system is increasingly unable to match the high repetition rate laser. The scanning speed of the polygon mirror scanner can reach 1000 m/s. Based on the FPGA (Field Programmable Gate Array) control system, the scanning speed of the polygon mirror scanner can be synchronized with the pulse repetition rate of the nanosecond laser so that after a single scan, there is only one laser pulse injection at each scanning position. This paper mainly studies the processing of titanium alloy templates by high-speed polygon mirror scanner and the influence of laser parameters and scanning parameters on the processing process. The processing depth will be changed by the reasonable adjustment of laser parameters. When the laser power reaches 500 W, the hole diameter can get 112 μm, the depth 156 μm, and the taper tends to be 0.325. There is a geometric relationship between scanning speed, laser pulse repetition rate, and scanning hole spacing, and different functions such as two-dimensional laser marking, laser drilling and laser scribing can be realized according to processing requirements. When the scanning speed of the polygon mirror scanner exceeds 800 m/s, the pulse repetition rate is 500 kHz, the spacing between holes is 1.6 mm, the spacing between lines is 1.6 mm, the overall scanning times are 30 times, and the surface processing of about 4000-hole positions takes only 1.5 seconds. At the end of this paper, a typical application case is presented. There are thousands or even tens of thousands of micro-holes on the surface of titanium alloy templates processed by a high-speed polygon mirror scanner. The template shows a good effect after the deposition of biological coating materials or related drugs and can be actively applied to the healing of traumatic bone tissue.
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