With the development of ultra-high screen-to-body ratio liquid crystal display (LCD) screen, extremely high requirements have placed on the cutting quality of LCD screen polarized film (POL). In this study, high-quality cut obtained using a 355 nm (ultraviolet light) nanosecond laser, and the cutting quality was analyzed with laser ablation process as the core. Firstly, by comprehensive experiments, narrowest heat-affected zone (HAZ) width of 12.07 ± 0.4 μm obtained when pulse repetition rate was 190 kHz, cutting speed was 40 mm/s and repeat times of laser cutting was 4, and the cross-section was smooth without obvious taper. Secondly, POL cutting mechanism with laser ablation as the core was summarized by analyzing the thermal decomposition process of POL. Finally, based on experimental results and laser ablation mechanism, effects of manufacturing parameters on cutting quality obtained. This work provides manufacturing technology reference and mechanism support for high-quality POL laser cutting.

随着超高屏占比液晶显示器（LCD）屏幕的发展，对LCD屏幕偏光膜（POL）的切割质量提出了极高的要求。在这项研究中，使用355 nm（紫外线）纳秒激光获得高质量的切割，并以激光烧蚀工艺为核心分析了切割质量。首先，通过综合实验，当脉冲重复频率为190 kHz，切割速度为40 mm / s，激光切割重复次数为4时，获得的最窄热影响区宽度为12.07±0.4μm。光滑，没有明显的锥度。其次，通过分析POL的热分解过程，总结了以激光烧蚀为核心的POL切割机理。最后，根据实验结果和激光烧蚀机理，制造参数对切削质量的影响。这项工作为高质量POL激光切割提供了制造技术参考和机构支持。