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Wavefront-error evaluation by mathematical analysis of experimental Foucault-test dataThe diffraction theory of the Foucault test provides an integral formula expressing the complex amplitude and irradiance distribution in the Foucault pattern of a test mirror (lens) as a function of wavefront error. Recent literature presents methods of inverting this formula to express wavefront error in terms of irradiance in the Foucault pattern. The present paper describes a study in which the inversion formulation was applied to photometric Foucault-test measurements on a nearly diffraction-limited mirror to determine wavefront errors for direct comparison with ones determined from scatter-plate interferometer measurements. The results affirm the practicability of the Foucault test for quantitative wavefront analysis of very small errors, and they reveal the fallacy of the prevalent belief that the test is limited to qualitative use only. Implications of the results with regard to optical testing and the potential use of the Foucault test for wavefront analysis in orbital space telescopes are discussed.
Document ID
19750059308
Document Type
Reprint (Version printed in journal)
Authors
Wilson, R. G. (NASA Langley Research Center Hampton, Va., United States)
Date Acquired
August 8, 2013
Publication Date
September 1, 1975
Publication Information
Publication: Applied Optics
Volume: 14
Subject Category
OPTICS
Distribution Limits
Public
Copyright
Other