Error influences of the shear element in interferometry for form characterization of optics

Jan-Hendrik Hagemann; Claas Falldorf; Gerd Ehret; Ralf B. Bergmann

doi:10.1117/12.2269932

Translator Disclaimer

26 June 2017 Error influences of the shear element in interferometry for form characterization of optics

Jan-Hendrik Hagemann, Claas Falldorf, Gerd Ehret, Ralf B. Bergmann

Author Affiliations +

Proceedings Volume 10329, Optical Measurement Systems for Industrial Inspection X; 103291T (2017) https://doi.org/10.1117/12.2269932
Event: SPIE Optical Metrology, 2017, Munich, Germany

Abstract

A shearing interferometer combined with an LED multispot illumination provides a high flexibility form characterization of optical surfaces as it is needed for aspheres and freeforms. Core element of the setup is the spatial light modulator as shearing element (SLM). Error influences due to the used blazed grating of the SLM need to be investigated. We show results of wavefront measurements with a Shack-Hartmann sensor which demonstrate residual structures of the grating at the wavefront under test. Additionally, simulated data are compared to the measurements to get a better understanding of the expected effects. These investigations help to correct the wavefront under test for this static error and improve the accuracy of the form characterisation.

Citation Download Citation

Jan-Hendrik Hagemann, Claas Falldorf, Gerd Ehret, and Ralf B. Bergmann "Error influences of the shear element in interferometry for form characterization of optics", Proc. SPIE 10329, Optical Measurement Systems for Industrial Inspection X, 103291T (26 June 2017); https://doi.org/10.1117/12.2269932

ACCESS THE FULL ARTICLE