In this paper, we investigate the frequency doubling of Q-switched partially coherent laser pulses. Such laser pulses are generated using a neodymium-doped yttrium aluminum garnet laser in which the laser cavity is a degenerate resonator. Electro-optic Q-switching is employed to generate laser pulses with a pulse width of approximately 10 ns. The spatial coherence of the output laser can be modulated by changing the size of a spatial filter within the laser cavity. The influence of spatial coherence on the conversion efficiency of the frequency doubling is studied. It is found that reducing the spatial coherence results in a slight reduction of the frequency-doubling conversion efficiency. However even in the case of low spatial coherence, the frequency-doubling conversion efficiency remains high, larger than 30%. The partially coherent laser beams with high frequency-doubling conversion efficiency can be applied to laser imaging, laser illumination, and inertial confinement fusion (ICF), etc.

在本文中，我们研究了调Q部分相干激光脉冲的倍频。这种激光脉冲是使用掺钕钇铝石榴石激光器产生的，其中激光腔是简并谐振器。采用电光调Q来产生脉冲宽度约为10 ns的激光脉冲。输出激光的空间相干性可以通过改变激光腔内空间滤波器的尺寸来调制。研究了空间相干性对倍频转换效率的影响。发现降低空间相干性会导致倍频转换效率略有降低。然而，即使在空间相干性较低的情况下，倍频转换效率仍然很高，大于30%。