A Simple Understanding of Laser Galvanometer

A laser galvanomter, also known as a laser scanner, is a high-precision scanning component used for laser processing. It mainly consists of an X-Y optical scanning head, electronic driver amplifier, and optical reflector. The controller provides signals, which drive the amplifying circuit to control the laser galvanomter. Through the deflection of the laser beam on the X-Y plane, it achieves high-precision laser processing.

Working Principle of Laser Galvanomter

The basic principle of a laser galvanomter is similar to that of an ammeter, with its core structure being a special oscillating motor. It generates torque in the magnetic field through electric coils, causing the rotor of the galvo to deflect. Unlike traditional rotating motors, the rotor of a laser galvanomter exerts a restoring torque through mechanical torsion springs or electronic methods, and the magnitude of this torque is proportional to the angle of deviation from the equilibrium position. When current passes through the coil, the generated electromagnetic torque balances with the restoring torque, and the rotor reaches a certain deflection angle. Since the deflection angle is proportional to the current, the laser galvanomter can accurately reflect changes in current, similar to the working principle of an ammeter, except that the pointer is replaced with an optical reflector.

Structure of Laser Galvanomter

The main structure of a laser galvanomter includes a moving coil, iron core, suspension, damping, indicators, and zero adjustment parts.

• Moving Coil: The moving coil of the laser galvanomter is suspended between the poles of a strong horseshoe-shaped magnet and the iron core. It is usually rectangular or circular in cross-section, with fine wires. The current in the moving coil is proportional to the deflection angle of the laser beam to be measured.

• Iron Core: The shape of the iron core depends on the shape of the coil. It provides a low magnetic resistance path and enhances the strength of the magnetic field, thereby increasing the deflection torque and sensitivity.

• Suspension: Thin strips of phosphor bronze are used as lead wires, and another lead is suspended in a spiral form. The suspension system must ensure that the coil rotates freely in the central position, avoiding friction with the magnet or iron core.

• Damping: Eddy current damping is used to slow the movement of the coil, preventing excessive oscillation, and ensuring the stability and accuracy of the laser galvanomter.

• Indicators and Zero Adjustment: A small mirror attached to the laser galvanomter reflects the beam to show the deflection angle using a scale. To precisely adjust the zero position of the galvo, the system is equipped with a torque head, ensuring accurate positioning of the beam.

Applications of Laser Galvanomter

Laser galvanomters are widely used in laser marking, laser engraving, laser welding, and other fields. In these processes, the laser galvo plays a crucial role. Its high precision is reflected in the ability to accurately control current and deflection angles, ensuring precise positioning of the laser beam during processing. The high speed of the laser galvo is evident in its ability to quickly control beam movement, meeting the demands of high-speed processing. Additionally, the compact size of the laser galvanomter makes it easy to integrate into laser processing systems.

In summary, the laser galvo, through its precise angle control and high-speed response, has become an indispensable core component in laser processing systems, driving the development of modern laser processing technology.