Unlike other ordinary light sources, laser cutting lasers can achieve energy concentration due to their monochromaticity, coherence, collimation and high energy density, thus causing damage to human organs (especially human eyes). . For the laser in the infrared spectrum region, the damage to the human body is mainly the thermal effect. For the laser light in the blue and violet spectral regions, the damage is mainly the photochemical effect. Therefore, when the human eye accidentally faces the laser light emitted from the laser or the fiber connector, it may cause damage to the eyes.