A simple method is presented for determining the waist position and the waist size of a Gaussian beam from measured spot sizes. The method does not require any least-squares process, and substitution of measured spot sizes directly into the formulas gives the waist parameters. Only few data are required to determine the parameters accurately as long as measured spot sizes contain small errors.
© 1986 Optical Society of America
Shojiro Nemoto, "Determination of waist parameters of a Gaussian beam," Appl. Opt. 25, 3859-3863 (1986)