Dating back to the mid-1960s, the carbon dioxide laser continues to be widely used today. CO2 lasers were among the first gas lasers to be developed and remain the highest-power continuous wave lasers on the market. In addition, CO2 lasers boast “the ratio of output power to pump power can be as large as 20%”, making them highly efficient (1). The lasers themselves are considered reasonably priced. That coupled with their high power levels and diverse applications have made CO2 lasers industrial workhorses.
Common Applications for Carbon Dioxide Lasers
Carbon dioxide lasers excel in many areas, particularly thick metal cutting, welding, marking, and engraving. The medical industry also uses CO2 lasers in surgical procedures, laser surgery, and skin resurfacing because water in human tissue absorbs the laser’s light frequency efficiently. In recent years, CO2 lasers have been explored as an alternative to traditional sutures for closing wounds. With this application, a laser beam is used to “weld” human tissue. The military also uses CO2 lasers in rangefinders.
Competition for Carbon Dioxide Lasers
Though they’ve been solid performers since the 1960s, CO2 lasers face some serious competition. Solid state lasers such as YAG and fiber lasers have much shorter wavelengths than CO2 lasers. These shorter wavelengths allow for better absorption in metal. However, solid state lasers tend to be much more expensive than CO2 lasers.
Low-cost laser diodes have entered the market, allowing for less expensive solid state lasers. Though CO2 lasers remain the laser of choice for thick metals both in terms of cut quality and cost, solid state laser technology may be catching up. Fiber lasers are able to cut thicker metals than in the past and are becoming more efficient.
That said, CO2 lasers remain strong. Not only are they reliable and efficient, they are also extremely versatile. For example, CO2 lasers can cut through leather, paper, and other materials so CO2 application “still represent a [significant] proportion of the materials processing market” (2). In some cases, even glass. Meanwhile fiber lasers cannot because their shorter wavelength simply doesn’t allow for it. In addition, the longer wavelengths of CO2 lasers are considered relatively eye-safe at lower intensities.
1. “Carbon Dioxide Laser”, Wikipedia, http://en.wikipedia.org/wiki/Carbon_dioxide_laser
2. “Master of Metal”, Coherent, http://www.coherent.com/download/9041/Master-of-Metal.pdf