The far-field intensity distribution of hollow Gaussian beams was investigated based on scalar diffraction theory. An analytical expression of the M<sup>2</sup> factor of the beams was derived on the basis of the second-order moments. Moreover, numerical examples to illustrate our analytical results are given.
© 2005 Optical Society of America
Optical Design and Fabrication
Degang Deng, Xiaoyong Fu, Chaoyang Wei, Jianda Shao, and Zhengxiu Fan, "Far-field intensity distribution and M2 factor of hollow Gaussian beams," Appl. Opt. 44, 7187-7190 (2005)