Laser marking systems have steadily gained popularity in industrial packaging and manufacturing over the last 30 years. Offering quick speeds, high accuracy, and quality coding results, laser marking systems are used to complete some of today’s most demanding marking tasks, including:

• Industrial beverage batch coding.
• Pharmaceutical and medical device coding.
• Chemical packaging marking.
• Aerospace/automotive part marking.

In these environments and others, laser marking systems enable operators to create permanent, high-contrast markings at industrial speeds. 

To accommodate the unique needs of different operations, laser marking systems come in a variety of forms. However, in terms of popularity, two laser marking technologies stand above the rest:

• Fiber laser machines
• CO2 laser machines

Both of these systems create markings using a highly-concentrated beam of light, rapidly heating material surfaces with pinpoint precision. As the laser heats a substrate’s surface, the affected portions are permanently altered, leaving behind a highly legible marking. 

However, fiber and CO2 laser systems differ in several other ways, many of which affect whether or not one system is well-suited for a specific operation. 

Below, we present a fiber laser vs. CO2 laser comparison to help potential users determine which option is right for them.

Fiber Laser vs. CO2 Laser: Basic Operational Differences and Why They Matter

As mentioned above, both fiber laser systems and CO2 laser systems mark materials using highly-concentrated beams of light; however, they differ in how they produce and direct their beams.

Let’s begin our fiber laser vs. CO2 laser comparison by correctly classifying these systems and reviewing some basic mechanical properties.

Fiber Lasers: A Solid-State Laser Technology

Fiber laser systems are a solid-state laser technology, meaning they use solid materials as a laser source. Within each fiber laser system is a component called a diode, which converts electricity into light. This light is pumped into a fiber-optic cable, where it travels through the system until it enters the optical cavity. 

The optical cavity is a section of the fiber-optic cable that contains a rare-earth “dopant” (i.e. a material that can alter the light’s electrical properties). As the light beam interacts with the dopant, the light exposure stimulates the electrons present in the rare-earth material. This stimulation causes a release of photons (i.e. light particles) of a specific wavelength. 

Simultaneously, the optical cavity reflects the light back and forth, focusing it into a concentrated laser beam. The beam is given a desired shape using components such as beam expanders and lenses. The system then releases the laser beam to the substrate to create the desired marking.

CO2 Lasers: A Gas-State Laser Technology

In contrast with fiber laser systems, CO2 laser systems are a type of gas-state laser technology, meaning they use gaseous materials as a laser source. 

Each CO2 laser system is built with a CO2 laser tube, which is a glass tube containing a mix of carbon dioxide, nitrogen, helium, and hydrogen. The system creates light by exposing the tube’s gaseous mix to high-voltage electricity. The electricity excites the gas particles and causes them to release light. 

The CO2 laser tube is bookended by two mirrors: a fully reflective mirror and a partially reflective mirror. The released light particles bounce between the mirrors, building in intensity and forming a beam. Once the light reaches sufficient brightness, the beam can pass by the partially reflective mirror and be discharged toward the substrate. 

Fiber Laser vs. CO2 Laser: Practical Differences

As a result of their different light sources, operating mechanics, and wavelengths, fiber and CO2 laser systems differ in several ways, including in:

• Substrate compatibility.
• Marking speeds.
• Overall operation costs.
• Ongoing consumable costs.

These differences will have a significant influence on whether a fiber or CO2 system will work efficiently in specific situations.  

For example, fiber lasers excel at metal marking and engraving due to their concentrated beam wavelength (1,064nm). This aptitude makes fiber laser systems a valuable addition to production lines that use metal cans. Conversely, CO2 laser beams have longer wavelengths, which makes them worse at marking most metal materials; however, they are well-suited for marking many organic materials, such as wood and rubber, that fiber lasers are incompatible with.

For a breakdown of fiber laser vs. CO2 laser material compatibility, see the table below:

Beyond substrate compatibility, other important specification differences between these two systems include:

• Marking speed: Although marking speed will change from model to model, fiber laser systems generally offer faster marking speeds as compared to CO2 models. Fiber laser beams are more highly focused than CO2 beams, allowing them to mark materials at higher speeds.
• Power consumption: Fiber laser machines require less power to mark materials compared to CO2 machines. This provides fiber laser users with lower overall operating costs.
• Consumable needs: Fiber lasers have fewer consumable needs than CO2 laser systems, which require gas to operate as well as periodic tube replacements. Fiber laser systems, on the other hand, simply require the occasional lens or nozzle replacement.
• Upfront cost: Fiber laser systems cost significantly more upfront than CO2 laser systems. Today, fiber systems can cost anywhere from $40,000 to $1 million, while industrial-level CO2 machines can cost as little as $10,000.

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