High Power CO Lasers And Their Application Potential

Abstract

Comparing the state of development of high power gas lasers for civil applications, it can be seen that the CO2 laser is a well established tool; the CO laser, however, essentially remained a laboratory device. Hence, the question arises whether there will be an advantage to develop high power CO lasers for industrial applications, too. After a brief recapitulation of the typical CO-related properties, to help answering this question, the application potential of the CO laser, will be discussed. There are several wavelength-related advantages of the CO laser like increased absorption depth in glasses and crystals increased focal power density, and reduced plasma shielding. Furthermore, transmissive optical materials have considerably improved values for absorption and damage threshold, and finally power transmission through optical fibers is much more realistic in the near future for the 5 μm spectral range. In contrast to the variety of promising applications is the number of experimentally verified ones. This is due to the fact that only a few lasers are existing in the power range and in the developmental stage to be used for applications. In experiments CO lasers demonstrated advantages in the field of cutting and drilling metals and uranium isotope separation. Lasers in the high power range are developed in Japan, in the Soviet Union and in Germany. The types of lasers investigated in these countries differ from each other by the methods of gas cooling and excitation. Comparisons between Co- and CO2 lasers show that the system efficiencies of CO lasers are slightly higher by a factor of 1.3; the operation costs of CO lasers are reduced by the same factor. Investment and operation costs can be reduced considerably if for the planned application a high focal power density is used. Furthermore, the volumes of CO and CO2 lasers are comparable at present and in the future.