Focus control of laser cutting machine

The laser cutting machine not only cuts metal plates with high precision but also has a smooth section without burrs. Whether it is cutting thick or thin plates, it can achieve good results. However, these effects are inseparable from the focus control of the laser cutting machine.
So, what is focus control? Friends who are familiar with laser cutting machines know that when cutting laser cutting machines with different materials and different thickness plates, in order to achieve a good cutting effect, the focus of the laser beam will be set in different places (pictured), which is called what we have Said focusing.
In the early days of laser cutting applications, the main method of focusing was done manually. Now with the development of laser technology, this manual focusing method has gradually been phased out, and the automatic focusing function has begun to be slowly realized. Peak laser's laser cutting machine can be equipped with automatic focusing function. So, some people will say that the optical path is integrated in the cutting head. Can the focusing function be achieved by changing the height of the cutting head? When the cutting head is raised, the focus position is high, and when the cutting head is lowered, the focus position is low. However, it turns out that it is not as simple as everyone thinks.
The bottom of the cutting head is a nozzle. During the cutting process, the distance between the nozzle and the workpiece (nozzle height) is about 0.5 to 1.5 mm. It may be regarded as a fixed value, that is, the nozzle height is unchanged, so it cannot be adjusted by lifting the cutting head (Otherwise the cutting process cannot be completed).
The focal length of the focusing lens is unchangeable, so you cannot expect to adjust the focus by changing the focal length. If you change the position of the focus lens, you can change the focus position: if the focus lens is lowered, the focus is lowered, and if the focus lens is raised, the focus is increased. -This is indeed a way to focus. A motor is used to drive the focusing lens for up and down movement to achieve automatic focus adjustment.
Another automatic focusing method is: before the light beam enters the focusing mirror, a variable curvature mirror (or tunable mirror) is placed. By changing the curvature of the mirror and changing the divergence angle of the reflected beam, the focus position is changed. As shown below.
With the automatic focusing function, the machine can automatically adjust the focus to a suitable position at high speed when processing workpieces of different materials and thicknesses. In this way, the processing efficiency of the laser cutting machine can be significantly improved, and the perforation time of the thick plate will be greatly reduced.

Therefore, for the laser cutting machine, the auto focus function is an important and indispensable function.