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Realisation of an accurate and repeatable wavelength scale for double subtractive monochromators
Published
Author(s)
Malcolm G. White
Abstract
We present the results and discussion of two methods for achieving a higher degree of wavelength accuracy of double grating monochromators. In particular, we assessed the benefits of using differential evolution curve fitting techniques to minimize wavelength uncertainties associated with the manufacture of lead screws in sine-bar driven monochromators. Absolute wavelength-scale uncertainties better than {plus or minus}0.1 nm can be realized using this technique. We also report the realization of an accurate and repeatable wavelength scale, using a novel calibration technique, that is applicable to a wide range of monochromators. We present results demonstrating the robustness of the technique by realizing an absolute wavelength scale, across four grating sets from 250 nm to 1600 nm, with scale uncertainties within {plus or minus}0.02 nm and repeatable to {plus or minus}0.005 nm.
White, M.
(2012),
Realisation of an accurate and repeatable wavelength scale for double subtractive monochromators, Metrologia, [online], https://doi.org/10.1088/0026-1394/49/6/779
(Accessed October 10, 2025)