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Updated: Aug 15, 2026

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
Complete spatial characterization of a pulsed doughnut-type beam by use of spherical optics and a cylindrical lens
J Serna1, F Encinas-Sanz, G Nemeş
1Departamento de Optica, Facultad de Ciencias Físicas, Universidad Complutense, Madrid, Spain. fiopt01@sis.ucm.es
Abstract:
A complete spatial characterization (in second-order moments) of a doughnut-type beam from a pulsed transversely excited atmospheric CO2 laser is described. It includes the measurement of the orbital angular momentum carried by the beam. The key element in the characterization is the use of a cylindrical lens in addition to the usual spherical optics. Internal features of the beam that would have remained hidden if only spherical optics were employed were revealed by use of the cylindrical lens. The experimental results are compared and agree with a theoretical Laguerre-Gauss mode beam.
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