High Power Diodes for Direct Processing

摘要

Since a few years high power diode lasers with a power in the range from a few ten watts up to several kilowatts are entering the industrial materials processing market. The basic element for a high power diode laser is a semiconductor laser bar, which contains several single emitters. This bar must be mounted onto a special microchannel heat sink for sufficient cooling. Combination of several of these basic units, i.e. incoherent coupling of a high number of single low power laser elements by special optical components, is used to scale the power up into the kilowatt range. As a consequence, the beam quality of state-of-the-art high power diode lasers is inferior in comparison with the conventional lasers. Nevertheless, these lasers are extremely attractive for those applications, where moderate beam qualities are acceptable or even advantageous, because of their high efficiency, their low running costs, their small size, their low weight and since they are very easy to use, easy to integrate and last but not least are almost service free.