The processing of the screen slit is to cut thousands of slits distributed according to a certain rule on the high-strength alloy steel pipe. The commonly used gap specifications are: the width of the gap is 0.15 to 3 mm; the length of the gap is 50 to 300 mm: the cross section of the gap is mainly rectangular and trapezoidal. During cutting, a focused high-density laser beam is used to irradiate the parts of the screen that need to be processed, while assisting coaxial oxygen blowing. The energy of the laser beam is absorbed by the material, causing the surface temperature of the irradiated material to rise sharply, melting or vaporizing the tube material, and Form holes. When the beam and the workpiece move relative to each other along a certain track, a slit of a certain shape can be processed on the tube. Compared with the traditional mechanical adding method, laser processing has many advantages: ①The slit of laser cutting is narrow, and the minimum slit width can reach 0.1mm; ②Laser cutting is a kind of high energy, high density, and good controllability. Contact processing, no tool wear and noise; ③High cutting efficiency, usually only takes ten seconds to process one slit, which is dozens of times the efficiency of machining; ④The workpiece is small in deformation, high in machining accuracy, and there is no residual arc at both ends of the gap , The seam shape is regular: ⑤The processing range is wide, not only can process straight rectangular seams, but also process trapezoidal seams and curved seams of different specifications.