Carbon monoxide lasers

A new generation of carbon monoxide (CO) lasers from Coherent offer enhanced processing characteristics for materials processing applications ranging from glass cutting and via drilling, to fractional skin resurfacing. This new class of high power CO lasers have similar lifetime, reliability and maintenance characteristics as the company’s slab discharge CO2 lasers.

CO lasers output at a wavelength of approximately 5µm, as opposed to 10.6µm for CO2 lasers. Since some materials which transmit at the longer (CO2) wavelength absorb at 5µm, this leads to advantages in various materials processing applications. For example, there is stronger absorption at 5µm in certain plastic films, polymers and water, as well as some dielectric materials and copper oxides used in printed circuit boards. This enables higher efficiency processing of these materials.

Conversely, there is very low absorption at 5µm in chalcogenide fibres, which opens up the potential for fibre delivery (the lack of a fibre delivery option has limited CO2 lasers in certain applications). Additionally, the shorter wavelength of the CO laser focuses to a spot size that is two times smaller than that of a CO2 laser, enabling significant advantages in the production of smaller holes and features, as well as narrower kerf widths when cutting.

The first commercial CO laser available from Coherent is the J-3 5µm, which outputs over 200W. The high quality beam (M² < 1.2) produced by this laser allows all the benefits of smaller spot size to be fully realised.


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