Galvanometer Scanning Accelerates Laser Processing (I)

Over the past two decades, laser processing systems have gained popularity in numerous industrial applications such as welding, cutting, engraving, engraving, drilling, and marking. The galvanometer scanning system is often used to quickly and accurately position the laser spot on the workpiece. This system uses a pair of rotatable mirrors to achieve a two-dimensional controllable laser beam deflection. The laser beam can be precisely positioned to obtain a prescribed pattern by moving the beam back and forth at a certain speed. The controller on the scan head alone determines the profile of the laser spot.

Compared with the traditional solution, laser material processing brings many advantages due to the use of the scanning system: high level of dynamic performance and processing speed; elimination of mechanical tool wear; non-contact processing; small and precisely defined heat affected area Unique flexibility, no further processing.

application

Laser marking is a key application for galvanometer scanning systems. The characters marked with laser have permanent features. In addition, they are very readable and do not require the use of consumables. This application is ideal for expiration date codes on food packaging or text on ATM cards and ID cards.

The scanning system has also been applied in many other fields, such as high-precision material processing, electronics (silicon processing, printed circuit board drilling), medical technology (laser eye surgery, coherence fundus tomography scanner), rapid manufacturing (laser rapid prototyping, laser sintering/melting), and cutting or welding with kilowatts of laser power.

Due to the different requirements on laser power, accuracy and processing speed, there are a large number of scanning system configurations on the market. Figure 1 gives an overview of the different applications, their requirements, and a suitable scan head.

Figure 1. Scanners with various configurations can be selected depending on different requirements and application needs.

Configuration

If you do not consider the application, the laser material processing system essentially relies on the following components: laser light source, beam shaping, beam positioning, and controller. It also requires the use of additional special-purpose components such as operating systems, image processing, or process control devices. Figure 2 shows the basic scan head system setup, and Figure 3 gives a detailed description of the different focusing mirror assemblies.

Figure 2: Laser with scan head. Focusing is achieved with the F-Theta flat-field lens; the varioCSCAN component positions the focus along the Z-axis.

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