Laser material processing requires intensities of up to 109 W/cm2 at power levels ranging from several watts to tens of kilowatts. Single laser diodes emit a highly divergent beam at much lower power. To make them available for material processing, radiation of many diode lasers has to be gathered and combined into one beam with reasonable beam quality. A number of different design approaches have been investigated worldwide by various research groups. In this paper, two commercially available high power diode laser systems are presented and assessed. By means of a comparison of beam characteristics, suitable applications in material processing are identified for both systems. Suggestions of possible industrial applications carried out at the Zentrum Fertigungstechnik Stuttgart are presented and discussed.
"Assessment of different high-power diode lasers for material processing", Proc. SPIE 3097, Lasers in Material Processing, (18 August 1997); doi: 10.1117/12.281120; https://doi.org/10.1117/12.281120