Measurement of Gaussian laser beam radius using the knife-edge technique: Improvement on data analysis

Departamento de Física, Universidade Federal da Paraíba, João Pessoa 58051-970, Paraíba, Brazil.
Applied Optics (Impact Factor: 1.78). 02/2009; 48(2):393-6. DOI: 10.1364/AO.48.000393
Source: PubMed


We revisited the well known Khosrofian and Garetz inversion algorithm [Appl. Opt.22, 3406-3410 (1983)] that was developed to analyze data obtained by the application of the traveling knife-edge technique. We have analyzed the approximated fitting function that was used for adjusting their experimental data and have found that it is not optimized to work with a full range of the experimentally-measured data. We have numerically calculated a new set of coefficients, which makes the approximated function suitable for a full experimental range, considerably improving the accuracy of the measurement of a radius of a focused Gaussian laser beam.

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