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Journal of the Optical Society of America A

Journal of the Optical Society of America A


  • Vol. 15, Iss. 2 — Feb. 1, 1998
  • pp: 449–455

Effective Fresnel-number concept for evaluating the relative focal shift in focused beams

Manuel Martínez-Corral, Carlos J. Zapata-Rodríguez, Pedro Andrés, and Enrique Silvestre  »View Author Affiliations

JOSA A, Vol. 15, Issue 2, pp. 449-455 (1998)

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We report on an analytical formulation, based on the concept of effective Fresnel number, to evaluate in a simple way the relative focal shift of rotationally nonsymmetric scalar fields that have geometrical focus and moderate Fresnel number. To illustrate our approach, certain previously known results and also some new focusing setups are analytically examined.

© 1998 Optical Society of America

OCIS Codes
(050.1940) Diffraction and gratings : Diffraction
(220.2560) Optical design and fabrication : Propagating methods

Manuel Martínez-Corral, Carlos J. Zapata-Rodríguez, Pedro Andrés, and Enrique Silvestre, "Effective Fresnel-number concept for evaluating the relative focal shift in focused beams," J. Opt. Soc. Am. A 15, 449-455 (1998)

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