WHEN TO OPT FOR A 532 NM WAVELENGTH LASER

If you’re working with a soft material, a 532 nm wavelength green laser might be your best option. However, we don’t recommend running out and purchasing one just yet. There are many considerations that go into choosing the best laser marking technology in addition to material, like application and mark type.

 WHAT IS LASER WAVELENGTH?

A simple definition of laser wavelength, which is measured in nanometers (nm), is the amount of energy or light a laser produces. Different types of laser emit different wavelengths. The shorter the wavelength, the more concentrated the energy. The greater the energy, the more light that material will absorb.

Greater absorption = Better quality mark

Shorter wavelength lasers, including green and UV lasers, are generally recommended for laser marking soft materials. They offer a higher absorption rate than infrared lasers (like your fiber and CO2 lasers) and are less likely to burn the surrounding material because they produce less heat. This is why this category of lasers are also referred to as “cold lasers.”

 Shortest Wavelength 180 – 400 nm Ultraviolet (UV) Light 

Moderate Wavelength 400 – 740 nm Visible (VIS) Light 

Longest Wavelength 700 nm – 1 mm Infrared (IR) Light 

For instance, laser marking machines in the infrared category, such as CO2, fiber, or diode-pumped technologies, are capable of creating high quality permanent marks on a wide variety of materials, from metals to plastics. However, these same machines can alter or even burn some heat-sensitive materials. This is because the laser energy is not fully absorbed, allowing too much light to pass through without interacting with (or, as we say, marking) the material.

You’re left with indecipherable logos, unreadable barcodes, or damaged parts – none of which is effective for part identification or traceability, not to mention overall equipment effectiveness (OEE).

Why does this happen?

A laser is essentially concentrated light, and each material absorbs light energy