方形光阑限制高斯光束的传输变换

对基模高斯光束经方形光阑限制光学系统的光斑传输变换规律进行了论述．对于任一共轴光学系统，在不考虑有效光阑前面元件的衍射和变换时，考察入射光经有效光阑和其后面的元件发生衍射，根据柯林斯公式，对于非成像光学系统，采用稳相法得到出射光场的振幅分布；对于成像光学系统，根据像传递原理得到出射光场的振幅分布，最后得出出射光斑大小由有效光阑边长与光阑处高斯光束腰斑大小比较决定的结论．

Propagation of Guassian beam in the optical system with square aperture stop

The propagation of the basic mode Guassian beam in the optical system with square aperture stop is discussed. In a coaxial optical system, regardless of the transformation and diffraction of the components before the aperture of grating, considering the transformation and diffraction of the aperture of grating and the components behind it, according to the Collins formula, the amplitude distribution of output light field of imaging system is given by way of stationary phase method, the amplitude distribution of output light field of non-imaging system is given following the imaging-relaying principle. A conclusion that the size of the output beam spot is decied by the size of aperture of grating and the size of the input beam spot at the aperture of grating is finally drawn.