Otro
Refractive and geometric lens characterization through multi-wavelength digital speckle pattern interferometry
Registro en:
Optics Communications. Amsterdam: Elsevier B.V., v. 281, n. 5, p. 1022-1029, 2008.
0030-4018
10.1016/j.optcom.2007.10.077
WOS:000252762900017
Autor
Barbosa, Eduardo A.
dos Santos, Silas C.
Resumen
Physical parameters of different types of lenses were measured through digital speckle pattern interferometry (DSPI) using a multimode diode laser as light source. When such lasers emit two or more longitudinal modes simultaneously the speckle image of an object appears covered of contour fringes. By performing the quantitative fringe evaluation the radii of curvature as well as the refractive indexes of the lenses were determined. The fringe quantitative evaluation was carried out through the four- and the eight-stepping techniques and the branch-cut method was employed for phase unwrapping. With all these parameters the focal length was calculated. This whole-field multi-wavelength method does enable the characterization of spherical and aspherical lenses and of positive and negative ones as well. (C) 2007 Elsevier B.V. All rights reserved.