How to judge compatibility between lasers and galvanometers

In order to judge whether a laser and galvanometer are compatible, one needs to pay attention to parameter matching, signal synchronization, and actual testing.Starting from the key parameters of the laser wavelength and galvanometer scanning speed, and combining these with common problems that arise in testing, this article offers a practical method for determining compatibility, to help you quickly resolve equipment matching issues.

Why is compatibility so important?

Many people, when they first start using laser engraving equipment, think "as long as it's bright enough, that's fine." But then they find that the engraving effect is blurry, the laser is not accurately positioned, or even that the galvo motor is burned out.In fact, most of the problems arise from the degree of compatibility between the laser and the scanning mirror.Just like shoes, the equipment is only useful if it fits the needs of the company.

Let's first look at these key parameters.

Wavelength matching is the basis.

For example, if you use a 1064-nm infrared laser with a galvanometer that only supports 532-nm green light, it's like "playing a tune to a cow.The design of the coating on an OGM directly determines which wavelengths of light it can reflect. Before purchasing, it is essential to check the "applicable wavelength range" in the technical manual.

The power handling capacity of a speaker is also important.

The mirror is like a sun block lotion, with different SPF values corresponding to different levels of protection.A high-power laser (such as a 50W unit) requires a mirror coated with gold or a special coating. A normal aluminum-coated mirror will, if used for a long time, either lose efficiency or burn black spots.

The scanning speed has to be synchronized.

The maximum speed of the galvanometer must match the modulation frequency of the laser.For example, the galvanometer can move at 8000 mm / s, but the laser's response frequency is only 20 kHz. At high speeds, this causes the laser to "skip" like a pen that can't keep up with the ink.

This is the hard truth of hands-on testing.

Just draw a square around it.

Don't rush to make the complex patterns. First use the software to draw a 10 mm square.If four corners of the square are obviously rounded off or the dimensions are off by more than 0.1 mm, it's probably because the galvanometer's linear correction doesn't match the laser's control signal.

Gradual power testing.

We gradually increased the laser power from 10 % to 100 %, and monitored the temperature of the galvanometer.If the motor gets too hot when the power reaches 70 %, then the design of the heat dissipation system is not compatible.At this point you either have to replace the mirror or install a water-cooling system. Don't be stingy with the money; it's better than burning out the motherboard.

Listening to the sound of the voice can be a good indicator as well.

When working normally, the galvanometer motor makes a slight whirring sound.If you hear any unusual noises or a sudden change in pitch, turn it off immediately! This is probably due to the motor losing step because of mismatched drive parameters. If you keep using it, the bearings could be ruined in a matter of minutes.

Common pitfalls.

Don't believe the "one size fits all" line! Last year we had a customer who bought an interface to save time, but the result was a signal delay that caused the engraving to be off by 3mm.The safest bet is to stick with the same brand, but if you really want to mix and match, then you should get the manufacturer to provide a matching plan.

When the parameters are at the boundary (for example, when the mirror is at the maximum power of the laser), it is recommended to leave a 20 % margin.When the temperature in the room goes up, the efficiency of the equipment in dissipating heat decreases, and it is easy to go over the limit when operating at the limit.