Open AccessRonchi test can detect piston by means of the defocusing term
Author(s) -
Javier Salinas-Luna,
Esther Martínez Luna,
Luis Salas,
I. Cruz-González,
Alejandro Cornejo-Rodríguez
Publication year - 2004
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/opex.12.003719
Subject(s) - piston (optics) , optics , transversal (combinatorics) , range (aeronautics) , term (time) , physics , acoustics , wavefront , materials science , mathematics , mathematical analysis , quantum mechanics , composite material
We present simulated results on piston detection applying the classical Ronchi test to a segmented surface. We have found that a piston error in a test segment, induces a change in the transversal aberration, that can be analyzed by mutually comparing the fringes frequency in each segment. We propose that the piston term of the segmented surface can be recovered by geometrically relating the change in transversal aberration with the piston term. To test this, we have simulated some ronchigrams for a known piston error, and we have been able to recover this term for a dynamic range comprised among 57nm and 550 microm. For piston errors > 550 microm a change in the transversal aberration can be appreciated and measured in the ronchigrams although these large pistons are now classical defocusings. Thus we have demonstrated that the Ronchi test can be an alternative method for the piston detection with a large dynamic range.