2600W偏振耦合高效率半导体激光光源

摘要

As the increasing applications of laser diodes in laser cladding and laser hardening, the single laser diode optical power can not meet the actual requirements. An improvement of the power and power density is necesary and it can be achieved by beam shaping and beam combination such as polarization coupling. The polarization coupling technology is used to couple two laser beams with thin-film plate polarizer. In this paper, two 808 nm vertically stacked arrays with an output power of 1 500 W was achieved. After fast axis and slow axis collimated, the polarization direction of one stacked arrays is rotated 90° through a half wave plate, thus, the polarization directions of two laser stack are vertical. The beams of two lasers are incident on thin-film plate polarizer; one transmits through it, and the other is reflected on it. Finally, two beams combine to one. Polarization coupling of two bars increases the power by a factor of 1.6, and the output power is 2 600 W, electro-optical conversion efficiency is more than 48%. The spot size is about 1 mm x 2 mm. This source reaches an intensity of 130 kW ? cm"2. This laser can be directly applied to cladding, surface hardening and other fields.%将两个中心波长为808 nm,输出功率为1500W的半导体激光叠阵,经过快慢轴准直后,利用半波片将其中一个叠阵的偏振方向旋转90°,使用偏振分光平板的耦合功能,将两个偏振方向相互垂直的激光耦合到一个光路.扩束后再通过焦距为100 mm的聚焦镜组聚焦,提高激光器的亮度.在工作电流为75 A时,输出功率达到了2600 W,电光转换效率为48％,聚焦后的光斑尺寸为lmm×2 mm,功率密度为130 kW ·cm-2,可直接应用于熔覆、表面硬化等加工领域.