The carbon dioxide (CO2) laser was invented by C. Kumar N. Patel in 1964 at Bell Laboratories.
It can also be called glass laser tube, is currently a high continuous output power of laser products, widely used in textiles, medical, materials processing, industrial manufacturing fields.
It has unique applications especially in the industries of packaging coding, non-metal material cutting, and medical aesthetics.
CO2 laser technology matured in the 1980s and has been widely used in industrial processing for more than two decades, including metal cutting, marking and engraving of various materials, as well as welding and cladding processing in automotive, shipbuilding and aerospace.
The current industrial CO2 laser wavelength is mainly 10.64μm, and the output is infrared light.
Its electro-optical conversion efficiency can generally reach 15% to 25%, which is already a good advantage compared to solid-state YAG lasers.
Its wavelength range determines that the beam can be well absorbed by a variety of materials such as steel metals, non-ferrous metals, precious metals, and non-metals.
Related reading: Ferrous vs Non-ferrous Metals
Its applicable material range is even wider than fiber lasers.
As the most important development application of current laser processing is still metal material processing, fiber laser since 2010 has set off a boom at home and abroad, especially in metal processing to replace part of the market for CO2 cutting.
This has given some people a great deal of misinformation: that the CO2 laser is obsolete and not very useful anymore.
In fact, this idea is very wrong.
CO2 lasers as the most technically mature, stable and reliable type of light source are also very mature in process development, and even today, many applications of CO2 lasers are still seen in Europe and the United States.
Many natural and synthetic materials have strong characteristic absorption in the 9-12 μm spectral range spanned by CO2 lasers, so there are many opportunities for materials processing and spectral analysis.
The beam properties of CO2 lasers dictate that they will still have unique application potential.
This article focuses on several common applications of CO2 lasers.
Metal material processing
Before the popularity of continuous fiber lasers, metal plate processing was basically the world of high power CO2 lasers.
I remember in 2012 at an exhibition, there has been a manufacturer grandly released 4KW CO2 cutting machine, can cut plate thickness of more than 20mm, a time to shock the industry.
Nowadays, the time has changed and 10,000+ watt fiber lasers are used to cut ultra-thick plates.
In steel cutting, it is true that CO2 cutting has been replaced by fiber cutting for the most part, but it does not mean that it has disappeared.
Fiber laser is easy to cut due to its finer spot, but becomes its disadvantage in welding.
Especially for thick plate joining, high power CO2 lasers have an advantage over fiber lasers.
Although beam oscillation was introduced a few years ago to overcome the disadvantages of fiber lasers, it is still not as good as the CO2 laser beam.
In addition to the welding of steel materials, in recent years, materials such as chromium-manganese alloy steel and aluminum alloys that are not easy to weld have also started to appear, some of these materials have a high melting point and some have a high reflectivity of light, which requires a high laser power when welding.
Material surface treatment
CO2 laser for surface treatment is mainly reflected in laser cladding, nowadays, although it can also be done with semiconductor laser, but before the emergence of high power semiconductor laser, laser cladding is basically also the world of CO2 laser.
Laser cladding is widely used in industrial fields such as molds, hardware, mining machinery, mechanical spindles, aerospace, offshore equipment and even new civil products.
CO2 lasers have a huge price and cost advantage over semiconductor lasers, and CO2 laser cladding is now a popular option.
Fabric fiber processing
In metal processing, CO2 laser faces the challenge of fiber laser and semiconductor laser, so the future application of CO2 laser is likely to focus on the application of non-metal materials, including glass, ceramics, fabric leather, wood, plastic, polymer, etc.
Customized applications for special areas
The nature of the CO2 laser beam offers great possibilities for customized special field applications, such as processing of polymers, plastics, ceramics, etc. CO2 lasers enable high speed cutting of polymer materials such as ABS, PMMA, PP, etc.
Using advanced CO2 laser with optimized optical pattern and optical path design to form a more perfect spot, it can reduce the heat affected area and cut high quality cell phone film products (PET protective film, display panel).
The unique advantages of CO2 laser cutting technology make it more suitable for film precision cutting than UV laser cutting technology, and it also better meets the needs of precision processing in the IT industry.
After the 1990s, high-energy pulsed medical devices represented by ultra-pulsed CO2 laser therapy machines emerged and were successfully applied, making breakthroughs in demanding applications, especially in laser aesthetics alone, with a very broad development prospect.
It is understood that CO2 laser-assisted deep sclerectomy, or CLASS for short, is a non-penetrating, non-subconjunctival follicle-dependent procedure that reduces intraocular pressure through trabecular meshwork, deep sclera and choroidal drainage of atrial fluid.
This revolutionary procedure has few intraoperative and postoperative complications; is non-filtration follicle-dependent and has no postoperative response to scarring; is simple, has a short learning curve, is easy to master, and is clinically useful.