In the parameter setting of laser marking machine, the power is adjusted by percentage, and the output power can be adjusted from 0% to 100%. The general default parameter is 50% output power. The greater the output power adjustment, the greater the laser output energy, and the easier it is to drill. After long-term use, the power of laser welding machine decreases, which determines the welding speed and single pulse energy. Power itself is a parameter, and it is also related to defocusing and welding speed. If the current is increased and the pulse width and frequency are kept constant, the single point energy will increase and the total laser output power will also increase. If the current and frequency remain unchanged, the pulse width will increase, the single point energy will also increase, and the total laser output power will also increase. If the current and pulse width remain unchanged, the single point energy remains unchanged, and if the frequency increases, the total laser output power will also increase. How to make a small deviation can be required by the light outlet of the beam expander (the laser at the light inlet must be in the center of the beam expander, and the normal deviation cannot exceed 1MM). If the deviation exceeds 1 mm, to move and fix the laser again, it may be necessary to disassemble the laser and process a set of suitable hole positions to calibrate the laser position. On this issue, we should not blindly adjust the optical path by adjusting the beam expander. Once the deviation is too large, the laser power and laser spot shaping effect will be greatly reduced, which has a great influence on the laser welding effect.