三种半导体阵列光谱组束结构的输出特性

基于光谱光束组合技术,利用光栅的衍射和外腔的反馈,并通过加入光束整形系统,将标准的半导体激光阵列的发光单元锁定在窄线宽的不同波长上,以近似平行光束沿组合方向输出,以实现半导体激光阵列输出光束质量的改善和线宽的压窄。实验中采用发光单元宽度100μm,周期500μm,由19个单元构成的标准阵列,分别对快、慢轴准直后光谱组束、光束整形后光谱组束和线宽压窄外腔组束进行了实验验证,实现了组合光束与单个发光单元近似的光束质量,同时得到了较窄的线宽输出,并对实验结果进行了分析。

Output characteristics of diode laser array by three different spectral beam combing structures

Based on spectral beam combining technology, with diffraction grating and external cavity feedback, each element of an array of diode laser is locked at different wavelengths in a narrow linewidth by inserting a beam shaping system. And the output beam is an approximately parallel light along the direction of combination. Beam quality improvement and linewidth narrowing of an array of diode laser are achieved. The standard diode laser array used in our experiment has 19 elements, with a width of 100 m and a period of 500 m for each element. Experiment is conducted on different spectral beam combing setups, including spectral beam combing after collimation in both fast and slow axes, spectral beam combing after beam shaping and beam combing in an external cavity with narrow-line width. The combining output beam has the same beam quality as that of a single emitter and the linewidth of such a beam is narrow. The experiment results are analyzed.