## 1 Introduction
In 2003, [PERSON] [15] studied laser scribing for chemical milling maskant and proposed that the light energy emitted from lasers in the 200-500 W range will reflect from the aluminum substrate with no damage to the substrate. In 2010, [PERSON] [8] studied the application of laser ablation in chemical milling in aeronautics and and analyzed laser power/speed on the interaction phenomenon and defect formation in the maskant laser cutting process under the condition of a CO\({}_{2}\) laser source. In 2012, [PERSON] [16] analyzed the scribing parameters through multiple parameter laser cutting experiments to realize flexible and accurate pattern scribing for chemical milling graphics. In 2020, [PERSON] [17] studied the relationship between laser power, scribing speed, laser frequency and scribing depth in process parameters, and pointed out that there is an obvious linear positive correlation between laser scribing power and scribing speed with scribing depth. In terms of other surface coating removal, [PERSON] [18] described the ablation of organic polymers on the basis of photothermal bond-breaking within the bulk material by assuming a first-order chemical reaction meets Arrhenius law. [PERSON]. [19] explored the ablation of gold nanoparticle films on polymer using a nanosecond pulsed laser and demonstrated high resolution and clean feature fabrication with small energy and selective multilayer processing. [PERSON] [20] reports an experimental investigation on the continuous CO\({}_{2}\) laser cutting of polymethylmethacrylate (PMMA) sheets. The influence of four process factors (laser power, cutting speed, assisting gas pressure and sheet thickness) on five process responses (kerr deviation, top heat affected zone, bottom heat affected zone, maximum surface roughness and rough area) were investigated. [PERSON]. [21] studied the mechanism and application of laser ablation and analyzed the photon absorption in the smoke area of laser etching polymer materials, which reduced the effective ablation density of the material surface, and affected the improvement of the surface etching speed precision. [PERSON]. [22] investigates the application of the CO\({}_{2}\) laser cutting process to three thermoplastic polymers, polyethylene (PE), polypropylene (PP) and polycarbonate (PC) in different thicknesses ranging from 2 to 10 mm. In the aspect of maskant removal by incident angle, there are few reports. [PERSON] [23]studied that the absorptivity is strongly altered by the grazing angle of incidence of the laser beam on the processing front. Owing to its specific Brewster-peak characteristics, the 10.64 \(\upmu\)m wavelength CO\({}_{2}\) laser shows an opposite trend with respect to roughness and angle-of-incidence compared to lasers in the wavelength range of 532-1070 nm. [PERSON]. [24] carried out the laser removal of small particles from a metal surface by changing the incident angle of the laser beam. It was found that a dramatic improvement of cleaning efficiency in terms of area and energy is observed when using the laser at a glancing angle of incidence as compared to perpendicular. The above research mainly focused on the plane plate or parts with large curvature and realized laser scribing at the vertical incidence angle, which can meet the requirements of first laser scribing in chemical milling to a certain extent. However, there are few reports on the research of laser scribing theoretical modeling and laser scribing by changing the laser incidence angle. In the above literature research, the process parameters applied to laser scribing are generally obtained by experimental methods. Although laser scribing experimental parameters can be used in the application and processing, the process parameters do not consider the speed change of laser equipment and cannot realize the real-time control in the NC system.