Focus control refers to the laser cutting machine in cutting different materials and plates of different thickness, in order to achieve better cutting effect, the focus of the laser beam will be set in different places, which is called focusing. With the breakthrough of industrial control technology, it is necessary to be able to carry out automatic focusing cutting head in laser cutting automation.

In the early application of laser cutting, the main way of focusing is to rely on manual. Now with the development of laser technology, this way of manual focusing has been gradually eliminated, and the automatic focusing function has been gradually realized.

The bottom of the laser cutting head is a nozzle. In the cutting process, the height of the nozzle does not change, so the focus cannot be adjusted by lifting the cutting head. The focal length of the focusing mirror cannot be changed, so we can't expect to focus by changing the focal length. If you change the position of the focus mirror, you can change the focus position: if the focus mirror is down, the focus will be down, if the focus mirror is up, the focus will be up, which is a way of focusing. A motor is used to drive the focusing mirror to move up and down to realize automatic focusing.

Another method of automatic focusing is to set a variable curvature mirror before the beam enters the focusing mirror. By changing the curvature of the mirror and the divergence angle of the reflected beam, the focus position can be changed.

With the auto focus function, when processing workpieces of different materials and thicknesses, the machine can automatically adjust the focus to the most appropriate position, which can significantly improve the processing efficiency of laser cutting machine, and greatly reduce the perforation time of thick plates. Therefore, for laser cutting machine, auto focus function is an important and indispensable function.