Open AccessMeasurement limitations in knife-edge tomographic phase retrieval of focused IR laser beams
Author(s) -
Manuel Silva-López,
José Marı́a Rico-Garcia,
Javier Alda
Publication year - 2012
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.20.023875
Subject(s) - zernike polynomials , optics , wavefront , phase retrieval , tomographic reconstruction , phase (matter) , physics , laser , beam (structure) , interferometry , measure (data warehouse) , intensity (physics) , irradiance , enhanced data rates for gsm evolution , tomography , fourier transform , computer science , telecommunications , quantum mechanics , database
An experimental setup to measure the three-dimensional phase-intensity distribution of an infrared laser beam in the focal region has been presented. It is based on the knife-edge method to perform a tomographic reconstruction and on a transport of intensity equation-based numerical method to obtain the propagating wavefront. This experimental approach allows us to characterize a focalized laser beam when the use of image or interferometer arrangements is not possible. Thus, we have recovered intensity and phase of an aberrated beam dominated by astigmatism. The phase evolution is fully consistent with that of the beam intensity along the optical axis. Moreover, this method is based on an expansion on both the irradiance and the phase information in a series of Zernike polynomials. We have described guidelines to choose a proper set of these polynomials depending on the experimental conditions and showed that, by abiding these criteria, numerical errors can be reduced.