Scattering from reflective diffraction gratings: the challenges of measurement and simulation

Abstract

Abstract The accurate simulation of stray light is essential for the prediction of signal detection fidelity in an optical instrument with high contrast requirements. In a spectrometer, the scattering from reflective gratings is poorly understood and difficult to characterize, but contributes significantly to the overall system stray light and reduction in contrast. This paper describes the approaches that will be taken at OHB System AG to establish a sufficiently precise fitting of bidirectional scatter distribution functions (BSDFs) to existing data obtained from measurements of scattering from gratings. The work is being undertaken in preparation for the analysis and fitting of a BSDF to the scattering from the grating for the FLEX low-resolution spectrometer that will be measured in the second half of 2017.