Which type of laser is best for engraving at the micron level?

How to choose the right laser for micron-level marking? Starting from actual needs, this article analyzes the impact of key parameters such as accuracy, wavelength, and power on marking effects, recommends scenarios for the application of fiber, ultraviolet, and femtosecond lasers, and provides selection guidelines to help users efficiently match high-precision laser marking equipment.

Why does laser engraving at the micron level require more from the laser?

Micro-scale engraving requires extremely high precision. The thermal effects of a normal laser or a spot that is too large can easily result in blurred edges.At this point, the wavelength, pulse width, and spot quality of the laser beam become key factors.For example, ultraviolet lasers are good at cold processing, and are suitable for processing brittle materials. Picosecond lasers have an ultra-short pulse that reduces thermal damage, but they are also more expensive.Before choosing a machine, be clear about what type of material you will be cutting and the depth of cut you require. Don't blindly go for the highest-spec machine.

What are the key parameters in a laser?

The wavelength determines the material's adaptability.

Metal is generally cut with a fiber laser (1064 nm), while brittle materials such as glass and ceramics are better suited to ultraviolet lasers (355 nm).The shorter the wavelength, the smaller the focus, and the higher the precision.

The size of the light spot directly affects the accuracy.

Don't just look at the "micron-level" figures in the advertising, but at the actual beam quality (M2 value).The closer M2 is to 1, the more concentrated the light.For example, a laser with an M2 value of 1.1 or less can easily achieve a line width of less than 10 microns.

Frequency and power balance.

The higher repetition rate speeds up engraving, but if the power is inadequate, the depth of the engraving will be unstable.For example, when cutting into stainless steel, a combination of a 20-watt power source and a 100-kilohertz frequency gives a good balance between efficiency and effect.

How do you choose with different budgets?

The best bang for the buck: fiber lasers.

When budgets are tight, fiber lasers have lower maintenance costs and longer lifespans, and they produce consistent results when engraving metals.However, it is not suitable for non-metallic materials.

UV lasers are a must for fine processing.

If you need to process plastics, semiconductors or other delicate materials, the cold processing characteristics of ultraviolet lasers are a major advantage.Although the costs are about 30 % higher, the increased yield can offset the higher cost.

Top of the line is picosecond laser.

For ultra-delicate work such as cutting medical devices or optical components, the heat effect of the picosecond laser is virtually zero.However, one machine can buy three fiber lasers, and is suitable for high-value products.

Avoiding the pitfalls

Don't be fooled by the "highest precision" sales pitch--the difference between lab results and what you get in the workshop can be as much as two-fold.

Be wary of low-priced second-hand equipment, as laser power declines sharply after the halfway point of the laser's life.

It is absolutely necessary to require sample testing, because the same design parameter can produce vastly different results on different materials.

Finally, a reminder: It's safer to rent before buying.Many suppliers provide equipment rental services, so you can try it out for a month before making a decision. It's much better than looking at 100 technical specifications.