We investigate the prominent role of $4f$ system in the suppression of beam shape distortion during laser power amplification. We find that $4f$ system can effectively suppress the distortion of the light spot caused by diffraction and thermal lens effect. In addition, the laser power can be amplified more efficiently by introducing a $4f$ system. Our results can benefit for applications with high requirements on the spot shape such as optical lattice and optical information processing.

中文翻译：

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一种抑制功率放大过程中光斑畸变的方法

我们调查了 $4F$系统在抑制激光功率放大期间的光束形状畸变方面。我们发现$4F$系统可以有效抑制衍射和热透镜效应引起的光斑畸变。另外，通过引入激光，可以更有效地放大激光功率。$4F$系统。我们的结果可对光斑形状和光信息处理等对光斑形状有高要求的应用带来好处。