What Is the Principle of the Laser Galvo?

The principle of laser galvo

A vector scanning galvanometer is an excellent vector scanning device. It is a special type of swing motor and the basic principle of the laser galvo is that the force generated by the energized coil in the magnetic field produces torque. However, unlike a rotating motor, its rotor is provided with a reset torque through a mechanical spring or electronic method, which is proportional to the angle of deviation from the balance position. When the coil is energized to a certain current and the rotor is deflected to a certain angle, the electromagnetic torque is equal to the restoring torque, so it cannot rotate like a normal motor but can only deflect. The deflection angle is proportional to the current, similar to a current meter, so the galvanometer is also called a current meter scanning galvanometer.

Scanning mirrors are professionally called high-speed scanning mirrors. The so-called mirrors can also be called ammeters. Its design concept is completely based on the design method of ammeters. The galvanometer scanning mirror replaces the pointer, and the signal of the probe is replaced by a direct current signal controlled by a computer to complete the predetermined action. Similar to the rotating mirror scanning system, this typical control system uses a pair of folding mirrors. However, the stepper motor that drives this set of mirrors is replaced by a servo motor. In this control system, the use of position sensors and the design concept of negative feedback loop further guarantee the accuracy of the system. The scanning speed and repeat positioning accuracy of the entire system have reached a new level.

Some laser galvos used belong to analog galvanometers, and the implementation mainly uses analog devices because analog devices are susceptible to electromagnetic radiation interference from the surrounding environment, so there may be phenomena such as scattered points, curved lines, and filled with irregular patterns during use. The digital galvanometer uses digital signals to operate the motor, which can effectively suppress environmental interference. Even if the electromagnetic interference in the working environment is serious, it can still be used normally.

Introduction to scanning laser galvanometer

The high-speed scanning laser galvo system is a high-performance rotating motor specially designed for optical scanning applications. The motor part uses a high-precision position sensor and is mainly used for fast and accurate positioning of the beam. The high-speed laser galvo is the culmination of many years of industrial galvo scanning system development and production experience. The motor specifically designed for mirror load can achieve the most ideal scanning performance. The bearing part is treated specially and can cope with long-term uninterrupted operation. The special design of the bearings can make the system achieve the highest dynamic performance and resonance characteristics. The internationally leading digital control method can effectively avoid various electromagnetic interference in the working environment, and advanced control algorithms can ensure that the system has a faster response speed.

The photoelectric sensor used in the high-speed scanning laser galvo has high resolution, very good repeat accuracy, and very small drift. The motor has a heating device and a temperature sensor and can work stably even under environmental fluctuations.