Galvanometer Scanner Working Principle

Galvanometer Scanner Working Principle

The galvanometer scanner is a special type oscillating motor. The basic principle is that the energized coil generates a torque in the magnetic field. However, unlike the rotating electric machine, the rotor is loaded with a reset torque by a mechanical spring or an electronic method. The size is proportional with rotor deviating angle from the equilibrium position. When the coil is energized with a certain mount of current, while the rotor is deflected to a certain angle, the electromagnetic torque is equal to the restoring moment, so it cannot rotate like a normal motor. It can only deflect, the deflection angle is proportional to the current, just like galvanometer, so it is also called galvanometer scanner.

The principle of the galvanometer scanner is: input a position signal, galvo motor will swing a certain angle according to the conversion ratio of certain voltage and angle. The whole process adopts closed-loop feedback control, which is composed of five control circuits-- position sensor, error amplifier, power amplifier, position distinguisher and current integrator. Digital galvanometer scanner is to convert the analog signal into a digital signal base on analog galvo scanner principle. Galvanometer scanner is the core component of the marking machine. Laser marking machine performance depends mainly on galvo scanner.

Analog galvanometer scanner is easily interfered by the electromagnetic radiation of the surrounding environment, so there will be scattered points, curved lines, and irregular shading during using.

Digital galvanometer scanner uses a digital signal to calculate and control the motor, which can effectively suppress environmental interference. Even if the working environment is seriously affected by electromagnetic interference, it can be used normally.