10 February 1981 Some Ideas On Ruling Engine Control Systems
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The magnitudes of various effects which may lead to wavefront errors in gratings ruled on the Harrison 'C' engine,and which are not corrected by the translation servo loop, are evaluated. It appears that thermal expansion is not a problem with the current level of temperature control (± 5 x 10 -3 C) and that variations in the refractive index of air could be compensated to the 10 nm level. However an interferometer which permits direct monitoring of the spacing between the diamond carriage assembly and the reference fused silica straightedge indicates larger wavefront errors may arise because of the present diamond carriage support.
© (1981) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Donald N.B. Hall, Donald N.B. Hall, } "Some Ideas On Ruling Engine Control Systems", Proc. SPIE 0240, Periodic Structures, Gratings, Moire Patterns, and Diffraction Phenomena I, (10 February 1981); doi: 10.1117/12.965671; https://doi.org/10.1117/12.965671

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