摘要
2kW射频板条CO_2激光器光束整形系统中空间滤波器具有消除旁瓣、提升光束质量的作用,研究其失调对输出光束的影响具有现实意义。通过理论和实验研究了空间滤波器失调对光强分布的影响,理论分析与实验结果基本一致。数值模拟了失调对输出功率的影响。结果表明,空间滤波器非稳方向横向位移失调对输出功率的影响不是线性的,输出功率损耗随着横向位移的增加急剧增大;对整形光束光强分布的影响很大,失调量大于0.2mm时就会使整形光束非稳方向出现明显的旁瓣。空间滤波器轴向位移失调对功率影响较小,但对光斑形状有比较明显的影响,失调量达到10mm时,整形光束两个方向的直径差可达3mm。空间滤波器旋转失调角度在10°以下时,对整形光束非稳方向光束的影响可以忽略,主要影响波导方向光束,旋转失调会使模式变差。旋转失调对功率也有较大的影响,失调角度为10°时,功率损耗增加到25%。
The spatial filter in the beam shaping system of a 2 kW radio frequency slab CO2 laser is used to eliminate side lobes and improve quality of output beams. It is important to study the effect of misaligned spatial filters on the characteristics of the shaped beam. The effect of the misaligned spatial filter on intensity distribution of the shaped beam was studied theoretically and experimentally. The theoretical simulation results are in agreement with the experimental results. Meanwhile, the effect of the misaligned spatial filter on output power of the shaped beam was studied by theoretical simulation. The results show that the effect of lateral displacement in the unstable direction of the spatial filter on the output power and the intensity distribution of the shaped beam is significant. The output power decreases and the side lobes appear as the lateral displacement increases. The shaped beam is not a circle while the spatial filter is axially-misaligned. The diameter difference is up to 3 mm when the axial displacement is 10 mm. The angle misalignment of the spatial filter mainly has impact on the shaped beam in the waveguide direction. The side lobes appear and the beam quality decreases as the angle misalignment increases. The loss of output power is up to 25% when the angle misalignment is 10°.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2016年第10期400-407,共8页
Acta Optica Sinica
基金
湖北省自然科学基金(2015CFB502)
湖北省教育厅基金(B2015011)
关键词
物理光学
射频板条CO2激光器
非稳波导混合腔
光束整形
空间滤波器
失调特性
physical optics
radio frequency slab CO2 laser
unstable-waveguide hybrid resonator
laser beam shaping
spatial filter
misalignment properties
