808 nm激光二极管阵列波长光束组合20 W输出

 基于多波长光束组合技术，利用光栅的衍射和外腔的反馈，将激光二极管阵列(LDA)发光单元锁定在不同的波长上，以近似平行光束沿光栅的-1级衍射方向组合输出，改善LDA输出光束质量。实验采用发光单元宽度为100 μm、周期为500 μm，由19个单元构成的1 cm普通商用LDA，在连续运行最大注入电流60.6 A时，自由运转输出功率49.8 W时，获得功率为20.1 W的组合光束稳定输出，其光谱宽度为15 nm，对应的远场发散角由约70 mrad变为1.66 mrad，改善后光束质量因子约为32，其值与单个发光单元的光束质量相当。

Wavelength beam combining of laser diode arrayto get 20 W CW circle spot emission

Based on wavelength beam combining, we use grating diffraction and external cavity feedback to lock all elements of the laser diode array(LDA) in different wavelengths, and the neighboring emitters have slight difference in locked wavelength. The output beam from the external cavity coupler mirror is nearly parallel with the same beam quality as single element of the LDA, and its brightness grows with the element number of the LDA increasing. The 1 cm linear array used in the experiment consists of 19 wide-aperture diodes with diode width of 100 μm and a fill factor is 0.2. When the free operating output power is 49.8 W and the maximal injection current is 60.6 A, the combined beam power is 20.1 W, the wavelength spread is about 15 nm, and the far field divergence angle varys from 70 mrad in free operating to 1.66 mrad in fast and slow axes in a single cavity. The corresponding beam quality factor is 32, which is the same as that of single element.