On the basis of generalized truncated second-order moments, a closed-form expression for the generalized <i>M</i><sup>2</sup> factor of hard-edge diffracted flattened Gaussian beams is derived that is determined by the beam order and the truncation parameter. Special cases are discussed. Moreover, it is shown that the <i>M</i><sup>2</sup> factor of truncated plane waves is equal to 4√3/3, independent of the aperture width.
© 2001 Optical Society of America
Baida Lü and Shirong Luo, "Generalized M2 factor of hard-edged diffracted flattened Gaussian beams," J. Opt. Soc. Am. A 18, 2098-2101 (2001)