Forward development of kW-class power diode laser bars

Progress is presented on ongoing research and development into ultra-high power and efficiency bars that achieve significantly higher useful optical output power and higher brightness than are currently commercially available. In previous work (2017), the authors reported on bars that deliver over 1 kW continuous wave (cw) diode laser power, when cooled using 15°C water. Our current studies are focused on increasing the usable output power (power within a targeted beam angle), which is essential for real world industrial applications. These ongoing studies have enabled the first demonstration of 500 W cw output power from a 10 mm x 6 mm laser diode bar with a lateral far field angle of only 8°. In efforts to further improve brightness, we also present our latest progress on high power SMEBs (Single Mode Emitter Bars). These emitters operate in a close to diffraction limited optical mode (M² 200 W cw laser bar power for SMEBs.