Our common lenses in laser marking machines are 50*50, 110*110, 160*160, 220*220, 300*300, 500*500, etc. How to use different lenses is actually how to choose different focal lengths. There are several factors that determine the size of the object to be marked: the size of the marking range; the fineness of the processing and the overall matching of the equipment.
The focal length has a certain relationship with the working distance. But the focal length is not equal to the working distance. When the object is large and the marking range is increased, the required lens is relatively large. Although many customers like to scan a large range of markings. However, if you increase the scan area blindly, there will be many problems. That is, when the scanning area reaches a certain level, the obtained spot diameter is large, and the gathering is not fine enough. When the spot size becomes large, the distortion becomes large, the power density of the laser decreases rapidly, and the working distance is lengthened, which inevitably leads to a loss of laser energy. Not conducive to precision processing.
In addition, when choosing the focal length, you should also consider the configuration of your equipment. If your equipment is a 20W fiber laser marking machine, then it is recommended that the lens should not exceed 300*300. The larger the laser lens, the laser consumption. It is also very large, the quality of the beam is not good, and the marking effect is also reduced.