Asian Journal of Physics Vol 31, No 7 (2022) 771-777

A review of the knife edge inteferometer (KEI)

Efren Santamaría Juárez1,2, ! and Alejandro Cornejo Rodríguez1
1Instituto Nacional de Astrofísica, Óptica y Electrónica (INAOE). Tonantzintla, Puebla. Apdo. Postal 216, Puebla, Pue. 72000
2Universidad Nacional Autónoma de México Instituto de Ciencias Aplicadas y Tecnológicas (UNAM, ICAT) Av. Universidad 3000, Circuito Exterior S/N, Ciudad Universitaria Apdo. Postal 70-186, C.P04510, CDMX, México

Dedicated to Prof Maria J Yzuel

When knife edge Interferometer (KEI) was first proposed for testing optical lenses, a collimating beam was used to illuminate the complete diameter of the lens under test together with a simple initial stitching of partial interferograms. In this study two new experimental schemes are described for the illumination of the lens or concave spherical surface under test, using a point light source located at any distance or at a distance 2f of the lens, or at the center of curvature of the concave optical surface. In order to improve the stitching of the two partial interferograms registered in this work, an extensive image processing digital work was performed on the two partial interferograms as well as on the final complete one. © Anita Publications. All rights reserved.
Keywords: Optical testing, Interferometry, Image Processing.

Peer Review Information
Method: Single- anonymous; Screened for Plagiarism? Yes
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