Power Blue and Green Laser Diodes and their Applications

摘要

InGaN based green laser diodes with output powers up to 50mW are now well established for variety of applications ranging from leveling to special lighting effects and mobile projection of 121m brightness. In future the highest market potential for visible single mode profile lasers might be laser projection of 201m. Therefore direct green single-mode laser diodes with higher power are required. We found that self heating was the limiting factor for higher current operation. We present power-current characteristics of improved R&D samples with up to 200mW in cw-operation. An optical output power of l00mW is reached at 215mA, a current level which is suitable for long term operation.Blue InGaN laser diodes are also the ideal source for phosphor based generation of green light sources of high luminance. We present a light engine based on LARP (Laser Activated Remote Phosphor) which can be used in business projectors of several thousand lumens on screen. We discuss the advantages of a laser based systems in comparison with LED light engines. LARP requires highly efficient blue power laser diodes with output power above 1W. Future market penetration of LARP will require lower costs. Therefore we studied new designs for higher powers levels. R&D chips with power-current characteristics up to 4W in continuous wave operation on C-mount at 25℃ are presented.