CO2 Laser Marking

On this page, we explain marking examples and characteristics of CO2 laser markers, which are perfect for applications such as marking resin and paper or processing films.

Applications

Mechanism and Characteristics of CO2 Lasers

Product Introduction

Applications

CO2 lasers have the longest wavelength of all commonly used lasers, more than ten times longer than that of standard wavelength lasers. 

In addition to paper and resin, it is also possible to mark wood, rubber, and transparent materials such as glass and PET plastic thanks to its heat-based marking method. On the other hand, it is hard to mark metal because the laser light has almost no reaction (is not absorbed).

Light wavelength distribution map

Applications

A Ultraviolet range  B Visible range  C Infrared range

Cartons

Cartons

Bottles

Bottles

Design marking

Design marking

Glass wafers

Glass wafers

Weatherstripping

Weatherstripping

Electronic PCBs

Electronic PCBs

Get the catalogue

for more details

Mechanism and Characteristics of CO2 Lasers

CO2 lasers are gas lasers that use CO2 gas as their medium. CO2 gas is filled and enclosed in the discharge tube where the electrodes used for electrical discharge are arranged. Plasma is generated within the gas by an electrical discharge, and the generated light is amplified as it travels back and forth between the total reflective mirror and the output coupler and is output as the laser.

Mechanism and Characteristics of CO2 Laser

A Total reflective mirror  B Electrode  C CO2 gas  D Laser  E Output coupler

Feature: CO2 lasers can also be used for cutting applications

CO2 lasers use heat on the target, which allows use for cutting applications such as cutting holds, gate cutting, and sticker half cutting in addition to marking. Compared to mechanical cutting using cutting tools, CO2 laser cutting has the advantage of preventing quality deterioration based on tool wear and being maintenance free.

Film cutting and hole cutouts

Film cutting and hole cutouts

Gate cutting

Gate cutting

Sheathing cutting

Sheathing cutting

Column

Improving quality with short-wavelength and thin laser types

KEYENCE offers a product lineup including short-wavelength and thin laser types for improved quality of CO2 laser marking. Each type offers the following advantages.

Conventional methods

Conventional methods

Damage is excessive and engravings are deep and rough

A Edge  B Depth

ML-Z

ML-Z

Damage is minimal and engravings are shallow and sharp

A Edge  B Depth

9.3 μm short wavelength model

The wavelength of the ML-Z Series’ laser is available at 10.6 μm as well as a shortened 9.3 μm to better suit the heat absorption characteristics of resin. With a higher absorptivity in resin, this shorter wavelength allows for more precise marking with shallower engraving and less surface swelling.

Marking on PET bottles

Standard wavelength CO2 laser marker

Standard wavelength CO2 laser marker

Short-wavelength CO2 laser marker

Short-wavelength CO2 laser marker

Standard model

Standard model

Thin laser model

Thin laser model

A Power density

Thin laser type

Compared to standard models, the laser spot diameter is smaller, enabling even finer marking. In addition, the smaller spot diameter allows for greater power density, which in turn allows for more efficient processing such as cutting and drilling.