强激光与粒子束, 2013, 25 (2): 310, 网络出版: 2013-01-07
体布拉格光栅外腔半导体激光器的光栅旋转角度容差
Gratings’ rotation angle tolerance for diode lasers with external cavity formed by volume Bragg grating
半导体激光器 体布拉格光栅 角度特性 窄线宽 高功率 diode laser volume Bragg grating angular character narrow linewidth high power
摘要
采用步进电机控制光栅角度,对200 μm和600 μm圆柱透镜准直的体布拉格光栅(VBG)外腔单管C封装半导体激光器进行了系统研究。实验结果表明:激光二极管(LD)驱动电流越大,准直效果越好,VBG的角度调整容差越小;快轴方向的准直效果越好,慢轴方向的光栅调节角度容差越大;对于衍射效率28%、厚1.4 mm的光栅,LD快轴发散角为7.3 mrad时,快轴方向的角度容差不大于3.2 mrad,慢轴方向的角度容差较快轴大约一个数量级。
Abstract
For high power linewidthnarrowed diode lasers, it’s important to study rotation angle tolerance of the volume Bragg grating (VBG) for narrowing the spectral linewidth of two dimensional diode laser stacks. The diode laser with the VBG’s external cavity and Cmounted modules is collimated by 200 μm and 600 μm cylindrical lens separately in the paper. The VBG’s angle tolerance is acquired by two stepper motors. According to the research, more accuracy is needed for the VBG’s adjustment with higher driving current and better beam collimation. If the laser diode is collimated better in fast axis direction, rotation angle tolerance in slow axis direction will be bigger. When a VBG with a diffraction efficiency of 28% and thickness of 1.4 mm is used to lock the wavelength of a laser diode with a fast axis divergence angle of 7.3 mrad, the grating’s rotation angle tolerance is no more than 3.2 mrad in the fast axis direction and that for the slow axis direction is one order of magnitude bigger.
李志永, 谭荣清, 徐程, 李琳, 刘世明, 赵志龙, 黄伟. 体布拉格光栅外腔半导体激光器的光栅旋转角度容差[J]. 强激光与粒子束, 2013, 25(2): 310. Li Zhiyong, Tan Rongqing, Xu Cheng, Li Lin, Liu Shiming, Zhao Zhilong, Huang Wei. Gratings’ rotation angle tolerance for diode lasers with external cavity formed by volume Bragg grating[J]. High Power Laser and Particle Beams, 2013, 25(2): 310.