Single mode and multi-mode laser, How to choose?

The module composition of fiber laser is divided into single-mode and multi-mode. In the cutting application, the focus spot has a great influence on the cutting quality. The fiber core of single-mode laser is relatively thin, the beam quality is better than that of multi-mode laser, the energy distribution is Gaussian distribution, the middle energy density is higher than that of multi-mode laser, and the three-dimensional diagram is a sharp circle of mountain.

The fiber core of the multimode laser is thicker, the beam quality is worse than that of the single mode, the energy distribution is more average than that of the single mode, and the three-dimensional image is an inverted cup. From the steepness of the edge, the multimode laser is much steeper than that of the single mode.

The cutting speed of 1 mm thin plate is 20% higher than that of multi-mode, and the visual effect is almost the same. However, starting from 2 mm, the speed advantage gradually decreases. Starting from 3 mm, the speed and effect advantages of high-power multi-mode laser are very obvious, as shown in the following figure.

So the advantage of single mode lies in thin plate, and the advantage of multi mode lies in thick plate. Single mode and multi mode have no comparative value. They are all a configuration of fiber laser. Just like a car, a car is suitable for road and off-road is suitable for mountain, but a car can also run in mountain and off-road can also run on road, Therefore, the choice of multimode or single-mode fiber laser depends on the actual processing needs of end users.

Single mode and multi-mode, how to choose?

Judging from the power level, the main processing material thickness of laser within 1000W is thin plate because of its low energy. Therefore, the single-mode configuration of laser within 1kW is more in line with the actual market situation, and the thickness of laser above 1kW should be considered. In terms of the whole processing industry, the improvement of processing quality is a rigid demand, which can not be compromised. Therefore, many high-power lasers will not consider single-mode selection, and must ensure that the processing quality is the first!

At the same time, the single-mode fiber core is generally thin, which means that the same power laser is transmitted in it, and the single-mode fiber core carries more light energy, which is a test for the material. At the same time, when cutting high reflection materials, the high intensity reflected light and the emitted laser are superimposed. If the tolerance of the fiber material is insufficient, it will be very easy to "burn the core". At the same time, it is also a challenge to the life of the core material! Therefore, many laser manufacturers in the configuration of high-power fiber laser still choose multimode configuration!