飞秒激光烧蚀光斑图像的周期灰度变化分析

在不同的飞秒激光烧蚀功率下,由于核心烧蚀区被烧蚀掉的材料体积不同,使得衍生的等离子体发光强度也不同.因此,有必要研究序列烧蚀光斑图像灰度变化与烧蚀工艺之间的关系.首先,连续采集2400帧光斑图像,获得光斑图像的灰度周期变化曲线,并对曲线进行小波去噪处理;其次,分析光斑图像周期性灰度变化曲线与烧蚀加工周期间的关系;再次分...

Analysis of periodic gray level change of spot image ablated by femtosecond laser

Under different femtosecond laser ablation power,due to the different volume of the ablated material in the core ablation region,the emission intensity of the derived plasma is also different.Therefore,it is necessary to study the relationship between the grey level change of sequential ablation spot image and ablation process.Firstly,2400 frames of spot images are collected continuously to obtain the spot image's grey periodic curve,and the wavelet denoising is performed on the curve.Secondly,the relationship between the spot image's periodic grey change curve and the ablation cycle is analysed.Thirdly,the corresponding relationship between the spot image's entropy and the spot image's grey level under different ablation states is analysed;Finally,the stability of grey level change of ablation spot image under the same ablation power but different ablation time is analysed.The results show that the periodic change of the ablated spot's grey level is consistent with the laser table's periodic motion.When the worktable moves to the left or right,the ablation process is stable,and the spot is bright.However,the ablated spot*s grey value is low at the worktable,s left and right ends.